rte->alias should point only to a user-written alias, but in these
cases that principle was violated. Fixing this causes some regression
test output changes: wherever rte->alias previously had a value and
is now NULL, rte->eref is now set to a generated name rather than to
rte->alias; and the scheme used to generate eref names differs from
what we were doing for aliases.
The upshot is that instead of "*SELECT*" or "*SELECT* %d",
EXPLAIN will now emit "unnamed_subquery" or "unnamed_subquery_%d".
But that's a reasonable descriptor, and we were already producing
that in yet other cases, so this seems not too objectionable.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Co-authored-by: Robert Haas <rhaas@postgresql.org>
Discussion: https://postgr.es/m/CA+TgmoYSYmDA2GvanzPMci084n+mVucv0bJ0HPbs6uhmMN6HMg@mail.gmail.com
Previously, heap_xlog_visible() called visibilitymap_pin() even after
getting a buffer from XLogReadBufferForRedoExtended() -- which returns a
pinned buffer containing the specified block of the visibility map.
This would just have resulted in visibilitymap_pin() returning early
since the specified page was already present and pinned, but it was
confusing extraneous code, so remove it. It doesn't seem worth
backporting, though.
It appears to be an oversight in 2c03216.
While we are at it, remove two VM-related redundant asserts in the COPY
FREEZE code path. visibilitymap_set() already asserts that
PD_ALL_VISIBLE is set on the heap page and checks that the vmbuffer
contains the bits corresponding to the specified heap block, so callers
do not also need to check this.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reported-by: Melanie Plageman <melanieplageman@gmail.com>
Reported-by: Kirill Reshke <reshkekirill@gmail.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CALdSSPhu7WZd%2BEfQDha1nz%3DDC93OtY1%3DUFEdWwSZsASka_2eRQ%40mail.gmail.com
A test has been added to ensure that conflict-relevant data is not
prematurely removed when a concurrent prepared transaction is being
committed on the publisher.
This test introduces an injection point that simulates the presence of a
prepared transaction in the commit phase, validating that the system
correctly delays conflict slot advancement until the transaction is fully
committed.
Additionally, the test serves as a safeguard for developers, ensuring that
the acquisition of the commit timestamp does not occur before marking
DELAY_CHKPT_IN_COMMIT in RecordTransactionCommitPrepared.
Reported-by: Robert Haas <robertmhaas@gmail.com>
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: shveta malik <shveta.malik@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/OS9PR01MB16913F67856B0DA2A909788129400A@OS9PR01MB16913.jpnprd01.prod.outlook.com
A new pgstats entry is created as a two-step process:
- The entry is looked at in the shared hashtable of pgstats, and is
inserted if not found.
- When not found and inserted, its fields are then initialized. This
part include a DSA chunk allocation for the stats data of the new entry.
As currently coded, if the DSA chunk allocation fails due to an
out-of-memory failure, an ERROR is generated, leaving in the pgstats
shared hashtable an inconsistent entry due to the first step, as the
entry has already been inserted in the hashtable. These broken entries
can then be found by other backends, crashing them.
There are only two callers of pgstat_init_entry(), when loading the
pgstats file at startup and when creating a new pgstats entry. This
commit changes pgstat_init_entry() so as we use dsa_allocate_extended()
with DSA_ALLOC_NO_OOM, making it return NULL on allocation failure
instead of failing. This way, a backend failing an entry creation can
take appropriate cleanup actions in the shared hashtable before throwing
an error. Currently, this means removing the entry from the shared
hashtable before throwing the error for the allocation failure.
Out-of-memory errors unlikely happen in the wild, and we do not bother
with back-patches when these are fixed, usually. However, the problem
dealt with here is a degree worse as it breaks the shared memory state
of pgstats, impacting other processes that may look at an inconsistent
entry that a different process has failed to create.
Author: Mikhail Kot <mikhail.kot@databricks.com>
Discussion: https://postgr.es/m/CAAi9E7jELo5_-sBENftnc2E8XhW2PKZJWfTC3i2y-GMQd2bcqQ@mail.gmail.com
Backpatch-through: 15
This commit fixes three issues:
1) When a disabled subscription is created with retain_dead_tuples set to true,
the launcher is not woken up immediately, which may lead to delays in creating
the conflict detection slot.
Creating the conflict detection slot is essential even when the subscription is
not enabled. This ensures that dead tuples are retained, which is necessary for
accurately identifying the type of conflict during replication.
2) Conflict-related data was unnecessarily retained when the subscription does
not have a table.
3) Conflict-relevant data could be prematurely removed before applying
prepared transactions on the publisher that are in the commit critical section.
This issue occurred because the backend executing COMMIT PREPARED was not
accounted for during the computation of oldestXid in the commit phase on
the publisher. As a result, the subscriber could advance the conflict
slot's xmin without waiting for such COMMIT PREPARED transactions to
complete.
We fixed this issue by identifying prepared transactions that are in the
commit critical section during computation of oldestXid in commit phase.
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: shveta malik <shveta.malik@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: Nisha Moond <nisha.moond412@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/OS9PR01MB16913DACB64E5721872AA5C02943BA@OS9PR01MB16913.jpnprd01.prod.outlook.com
Discussion: https://postgr.es/m/OS9PR01MB16913F67856B0DA2A909788129400A@OS9PR01MB16913.jpnprd01.prod.outlook.com
This commit allows to log the raw parse tree in the same way we
currently log the parse tree, rewritten tree, and plan tree.
To avoid unnecessary log noise for users not interested in this
detail, a new GUC option, "debug_print_raw_parse", has been added.
When starting the PostgreSQL process with "-d N", and N is 3 or higher,
debug_print_raw_parse is enabled automatically, alongside
debug_print_parse.
Author: Chao Li <lic@highgo.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Tatsuo Ishii <ishii@postgresql.org>
Reviewed-by: John Naylor <johncnaylorls@gmail.com>
Discussion: https://postgr.es/m/CAEoWx2mcO0Gpo4vd8kPMAFWeJLSp0MeUUnaLdE1x0tSVd-VzUw%40mail.gmail.com
This set of changes removes the list of available buffers and instead simply
uses the clock-sweep algorithm to find and return an available buffer. This
also removes the have_free_buffer() function and simply caps the
pg_autoprewarm process to at most NBuffers.
While on the surface this appears to be removing an optimization it is in fact
eliminating code that induces overhead in the form of synchronization that is
problematic for multi-core systems.
The main reason for removing the freelist, however, is not the moderate
improvement in scalability, but that having the freelist would require
dedicated complexity in several upcoming patches. As we have not been able to
find a case benefiting from the freelist...
Author: Greg Burd <greg@burd.me>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/70C6A5B5-2A20-4D0B-BC73-EB09DD62D61C@getmailspring.com
Add an assert to visibilitymap_set() that the provided heap buffer is
exclusively locked, which is expected.
Also, enhance the debug logging message to specify which VM flags were
set.
Based on a related suggestion by Kirill Reshke on an in-progress
patchset.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CALdSSPhAU56g1gGVT0%2BwG8RrSWE6qW8TOfNJS1HNAWX6wPgbFA%40mail.gmail.com
When executing a MERGE UPDATE action, if there is more than one
concurrent update of the target row, the lock-and-retry code would
sometimes incorrectly identify the latest version of the target tuple,
leading to incorrect results.
This was caused by using the ctid field from the TM_FailureData
returned by table_tuple_lock() in a case where the result was TM_Ok,
which is unsafe because the TM_FailureData struct is not guaranteed to
be fully populated in that case. Instead, it should use the tupleid
passed to (and updated by) table_tuple_lock().
To reduce the chances of similar errors in the future, improve the
commentary for table_tuple_lock() and TM_FailureData to make it
clearer that table_tuple_lock() updates the tid passed to it, and most
fields of TM_FailureData should not be relied on in non-failure cases.
An exception to this is the "traversed" field, which is set in both
success and failure cases.
Reported-by: Dmitry <dsy.075@yandex.ru>
Author: Yugo Nagata <nagata@sraoss.co.jp>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/1570d30e-2b95-4239-b9c3-f7bf2f2f8556@yandex.ru
Backpatch-through: 15
SlruRecentlyUsed() is an inline function since 53c2a97a92, not a
macro. The description of long_segment_names was missing at the top of
SimpleLruInit(), part forgotten in 4ed8f0913b.
Author: Julien Rouhaud <rjuju123@gmail.com>
Discussion: https://postgr.es/m/aLpBLMOYwEQkaleF@jrouhaud
Backpatch-through: 17
This commit changes some functions related to the data type numeric to
use the soft error reporting rather than a custom boolean flag (called
"have_error") that callers of these functions could rely on to bypass
the generation of ERROR reports, letting the callers do their own error
handling (timestamp, jsonpath and numeric_to_char() require them).
This results in the removal of some boilerplate code that was required
to handle both the ereport() and the "have_error" code paths bypassing
ereport(), unifying everything under the soft error reporting facility.
While on it, some duplicated error messages are removed. The function
upgraded in this commit were suffixed with "_opt_error" in their names.
They are renamed to "_safe" instead.
This change relies on d9f7f5d32f, that has introduced the soft error
reporting infrastructure.
Author: Amul Sul <sulamul@gmail.com>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Discussion: https://postgr.es/m/CAAJ_b96No5h5tRuR+KhcC44YcYUCw8WAHuLoqqyyop8_k3+JDQ@mail.gmail.com
pg_lsn includes pg_lsn_in_internal() for the purpose of parsing a LSN
position for the GUC recovery_target_lsn (21f428ebde). It relies on a
boolean called "have_error" that would be set when the LSN parsing
fails, then let its callers handle any errors.
d9f7f5d32f has added support for soft error reporting. This commit
removes some boilerplate code and switches the routine to use soft error
reporting directly, giving to the callers of pg_lsn_in_internal()
the possibility to be fed the error message generated on failure.
pg_lsn_in_internal() routine is renamed to pg_lsn_in_safe(), for
consistency with other similar routines that are given an escontext.
Author: Amul Sul <sulamul@gmail.com>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Discussion: https://postgr.es/m/CAAJ_b96No5h5tRuR+KhcC44YcYUCw8WAHuLoqqyyop8_k3+JDQ@mail.gmail.com
Commit 38b602b028 modified this function to allocate enough space
for MAX_NAMED_TRANCHES (256) requests, which is likely far more
than most clusters need. This commit reverts that change so that
it first allocates enough space for only 16 requests and resizes
the array when necessary. While at it, remove the check for too
many tranches from this function. We can now rely on
InitializeLWLocks() to do that check via its calls to
LWLockNewTrancheId() for the named tranches.
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Discussion: https://postgr.es/m/aLmzwC2dRbqk14y6%40nathan
When executing a MERGE, check that the target relation supports all
actions mentioned in the MERGE command. Specifically, check that it
has a REPLICA IDENTITY if it publishes updates or deletes and the
MERGE command contains update or delete actions. Failing to do this
can silently break replication.
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Tested-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/OS3PR01MB57180C87E43A679A730482DF94B62@OS3PR01MB5718.jpnprd01.prod.outlook.com
Backpatch-through: 15
If an INSERT has an ON CONFLICT DO UPDATE clause, the executor must
check that the target relation supports UPDATE as well as INSERT. In
particular, it must check that the target relation has a REPLICA
IDENTITY if it publishes updates. Formerly, it was not doing this
check, which could lead to silently breaking replication.
Fix by adding such a check to CheckValidResultRel(), which requires
adding a new onConflictAction argument. In back-branches, preserve ABI
compatibility by introducing a wrapper function with the original
signature.
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Tested-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/OS3PR01MB57180C87E43A679A730482DF94B62@OS3PR01MB5718.jpnprd01.prod.outlook.com
Backpatch-through: 13
The counters saved from pgWalUsage, used for the difference calculations
when flushing the backend WAL stats, are updated when calling
pgstat_flush_backend() under PGSTAT_BACKEND_FLUSH_WAL, and not
pgstat_report_wal(). The comment updated in this commit referenced the
latter, but it is perfectly OK to flush the backend stats independently
of the WAL stats.
Noticed while looking at this area of the code, introduced by
76def4cdd7 as a copy-pasto.
Backpatch-through: 18
There are two ways for shared libraries to allocate their own
LWLock tranches. One way is to call RequestNamedLWLockTranche() in
a shmem_request_hook, which requires the library to be loaded via
shared_preload_libraries. The other way is to call
LWLockNewTrancheId(), which is not subject to the same
restrictions. However, LWLockNewTrancheId() does require each
backend to store the tranche's name in backend-local memory via
LWLockRegisterTranche(). This API is a little cumbersome and leads
to things like unhelpful pg_stat_activity.wait_event values in
backends that haven't loaded the library.
This commit moves these LWLock tranche names to shared memory, thus
eliminating the need for each backend to call
LWLockRegisterTranche(). Instead, the tranche name must be
provided to LWLockNewTrancheId(), which immediately makes the name
available to all backends. Since the tranche name array is
append-only, lookups can ordinarily avoid locking as long as their
local copy of the LWLock counter is greater than the requested
tranche ID.
One downside of this approach is that we now have a hard limit on
both the length of tranche names (NAMEDATALEN-1 bytes) and the
number of dynamically-allocated tranches (256). Besides a limit of
NAMEDATALEN-1 bytes for tranche names registered via
RequestNamedLWLockTranche(), no such limits previously existed. We
could avoid these new limits by using dynamic shared memory, but
the complexity involved didn't seem worth it. We briefly
considered making the tranche limit user-configurable but
ultimately decided against that, too. Since there is still a lot
of time left in the v19 development cycle, it's possible we will
revisit this choice.
Author: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Rahila Syed <rahilasyed90@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CAA5RZ0vvED3naph8My8Szv6DL4AxOVK3eTPS0qXsaKi%3DbVdW2A%40mail.gmail.com
Commit 6359989654 had it so that the parameter "debug_discard_caches"
did not exist unless DISCARD_CACHES_ENABLED was defined (typically via
enabling asserts). This was a mistake, it did not correspond to the
prior setup. Several tests use this parameter, so they were now
failing if you did not have asserts enabled.
Store the information in guc_tables.c in a .dat file similar to the
catalog data in src/include/catalog/, and generate a part of
guc_tables.c from that. The goal is to make it easier to edit that
information, and to be able to make changes to the downstream data
structures more easily. (Essentially, those are the same reasons as
for the original adoption of the .dat format.)
Reviewed-by: John Naylor <johncnaylorls@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: David E. Wheeler <david@justatheory.com>
Discussion: https://www.postgresql.org/message-id/flat/dae6fe89-1e0c-4c3f-8d92-19d23374fb10%40eisentraut.org
SubPlan nodes are typically built very early, before any RelOptInfos
have been constructed for the parent query level. As a result, the
simple_rel_array in the parent root has not yet been initialized.
Currently, during cost estimation of a SubPlan's testexpr, we may call
examine_variable() to look up statistical data about the expressions.
This can lead to "no relation entry for relid" errors.
To fix, pass root as NULL to cost_qual_eval() in cost_subplan(), since
the root does not yet contain enough information to safely consult
statistics.
One exception is SubPlan nodes built for the initplans of MIN/MAX
aggregates from indexes. In this case, having a NULL root is safe
because testexpr will be NULL. Additionally, an initplan will by
definition not consult anything from the parent plan.
Backpatch to all supported branches. Although the reported call path
that triggers this error is not reachable prior to v17, there's no
guarantee that other code paths -- especially in extensions -- could
not encounter the same issue when cost_qual_eval() is called with a
root that lacks a valid simple_rel_array. The test case is not
included in pre-v17 branches though.
Bug: #19037
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Diagnosed-by: Tom Lane <tgl@sss.pgh.pa.us>
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19037-3d1c7bb553c7ce84@postgresql.org
Backpatch-through: 13
SLRU bank locks are referred as "bank locks" or "SLRU bank locks" in the
code comments. The comments updated in this commit use the latter term.
Oversight in 53c2a97a92, that has replaced the single ControlLock by
the bank control locks.
Author: Julien Rouhaud <julien.rouhaud@free.fr>
Discussion: https://postgr.es/m/aLUT2UO8RjJOzZNq@jrouhaud
Backpatch-through: 17
COPY TO does not support a WHERE clause, and currently fails with the error:
ERROR: WHERE clause not allowed with COPY TO
Since the intended behavior can be achieved by using
COPY (SELECT ... WHERE ...) TO, this commit adds a HINT
to the error message:
HINT: Try the COPY (SELECT ... WHERE ...) TO variant.
This makes the error more informative and helps users
quickly find the alternative usage.
Author: Atsushi Torikoshi <torikoshia@oss.nttdata.com>
Reviewed-by: Jim Jones <jim.jones@uni-muenster.de>
Discussion: https://postgr.es/m/3520c224c5ffac0113aef84a9179f37e@oss.nttdata.com
Previously, duplicate labels in CREATE TYPE AS ENUM were caught by
the unique index on pg_enum, resulting in a generic error message.
While this was evidently intentional, it's not terribly user-friendly,
nor consistent with the ALTER TYPE cases which take more care with
such errors. This patch adds an explicit check to produce a more
user-friendly and descriptive error message.
A potential objection to this implementation is that it adds O(N^2)
work to the creation operation. However, quick testing finds that
that's pretty negligible below 1000 enum labels, and tolerable even
at 10000. So it doesn't really seem worth being smarter.
Author: Yugo Nagata <nagata@sraoss.co.jp>
Reviewed-by: Rahila Syed <rahilasyed90@gmail.com>
Reviewed-by: Jim Jones <jim.jones@uni-muenster.de>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/20250704000402.37e605ab0c59c300965a17ee@sraoss.co.jp
This change replaces seven functions definitions by macros, reducing a
bit some repetitive patterns in the code. An interesting side effect is
that this removes an inconsistency in the naming of SLRU increment
functions with the field names.
This change is similar to 850f4b4c8c, 8018ffbf58 or 83a1a1b566.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/aLHA//gr4dTpDHHC@ip-10-97-1-34.eu-west-3.compute.internal
This commit introduces a new subscription parameter,
max_retention_duration, aimed at mitigating excessive accumulation of dead
tuples when retain_dead_tuples is enabled and the apply worker lags behind
the publisher.
When the time spent advancing a non-removable transaction ID exceeds the
max_retention_duration threshold, the apply worker will stop retaining
conflict detection information. In such cases, the conflict slot's xmin
will be set to InvalidTransactionId, provided that all apply workers
associated with the subscription (with retain_dead_tuples enabled) confirm
the retention duration has been exceeded.
To ensure retention status persists across server restarts, a new column
subretentionactive has been added to the pg_subscription catalog. This
prevents unnecessary reactivation of retention logic after a restart.
The conflict detection slot will not be automatically re-initialized
unless a new subscription is created with retain_dead_tuples = true, or
the user manually re-enables retain_dead_tuples.
A future patch will introduce support for automatic slot re-initialization
once at least one apply worker confirms that the retention duration is
within the configured max_retention_duration.
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: shveta malik <shveta.malik@gmail.com>
Reviewed-by: Nisha Moond <nisha.moond412@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/OS0PR01MB5716BE80DAEB0EE2A6A5D1F5949D2@OS0PR01MB5716.jpnprd01.prod.outlook.com
Constraint expressions and statistics expressions loaded from the
system catalogs need to be run through const-simplification, because
the planner will be comparing them to similarly-processed qual
clauses. Without this step, the planner may fail to detect valid
matches.
Currently, NullTest clauses in these expressions may not be reduced
correctly during const-simplification. This happens because their Var
nodes do not yet have the correct varno when eval_const_expressions is
applied. Since eval_const_expressions relies on varno to reduce
NullTest quals, incorrect varno can cause problems.
Additionally, for statistics expressions, eval_const_expressions is
called with root set to NULL, which also inhibits NullTest reduction.
This patch fixes the issue by ensuring that Vars are updated to have
the correct varno before const-simplification, and that a valid root
is passed to eval_const_expressions when needed.
Author: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/19007-4cc6e252ed8aa54a@postgresql.org
A proposed patch would place a limit of NAMEDATALEN-1 (i.e., 63)
bytes on the names of dynamically-allocated LWLock tranches, but
GetNamedDSA() and GetNamedDSHash() may register tranches with
longer names. This commit lowers the maximum DSM registry entry
name length to NAMEDATALEN-1 bytes and modifies GetNamedDSHash() to
create only one tranche, thereby allowing us to keep the DSM
registry's tranche names below NAMEDATALEN bytes.
Author: Sami Imseih <samimseih@gmail.com>
Discussion: https://postgr.es/m/aKzIg1JryN1qhNuy%40nathan
Show the requested lock level and the object being waited on,
in the same format we use for deadlock reports and similar errors.
This is particularly helpful for debugging lock-timeout errors,
since otherwise the user has very little to go on about which
lock timed out. The performance cost of setting up the callback
should be negligible compared to the other tracing support already
present in WaitOnLock.
As in the deadlock-report case, we just show numeric object OIDs,
because it seems too scary to try to perform catalog lookups
in this context.
Reported-by: Steve Baldwin <steve.baldwin@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/1602369.1752167154@sss.pgh.pa.us
Using the LWLockCounter requires first calculating its address in
shared memory like this:
LWLockCounter = (int *) ((char *) MainLWLockArray - sizeof(int));
Commit 82e861fbe1 started this trend in order to fix EXEC_BACKEND
builds, but it could also be fixed by adding it to the
BackendParameters struct. The current approach is somewhat
difficult to follow, so this commit switches to the latter. While
at it, swap around the code in LWLockShmemSize() to match the order
of assignments in CreateLWLocks() for added readability.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/aLDLnan9gNCS9fHx%40nathan
It's possible that if the only live partition is concurrently dropped
and try_table_open() fails, that the bms_del_member() will pfree the
live_parts Bitmapset. Since the bms_del_member() call does not assign
the result back to the live_parts local variable, the while loop could
segfault as that variable would still reference the pfree'd Bitmapset.
Backpatch to 15. 52f3de874 was backpatched to 14, but there's no
bms_del_member() there due to live_parts not yet existing in RelOptInfo in
that version. Technically there's no bug in version 15 as
bms_del_member() didn't pfree when the set became empty prior to
00b41463c (from v16). Applied to v15 anyway to keep the code similar and
to avoid the bad coding pattern.
Author: Bernd Reiß <bd_reiss@gmx.at>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/6b88f27a-c45c-4826-8e37-d61a04d90182@gmx.at
Backpatch-through: 15
I think the error message for a different condition was inadvertently
copied.
This problem seems to have been introduced by commit a4d75c86bf.
Author: Álvaro Herrera <alvherre@kurilemu.de>
Reported-by: jian he <jian.universality@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Backpatch-through: 14
Discussion: https://postgr.es/m/CACJufxEZ48toGH0Em_6vdsT57Y3L8pLF=DZCQ_gCii6=C3MeXw@mail.gmail.com
BufferGetPage() already returns type Page, so casting it to Page
doesn't achieve anything. A sizable number of call sites does this
casting; remove that.
This was already done inconsistently in the code in the first import
in 1996 (but didn't exist in the pre-1995 code), and it was then
apparently just copied around.
Author: Kirill Reshke <reshkekirill@gmail.com>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Reviewed-by: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://www.postgresql.org/message-id/flat/CALdSSPgFhc5=vLqHdk-zCcnztC0zEY3EU_Q6a9vPEaw7FkE9Vw@mail.gmail.com
For a child relation, we should not assume that its parent's
unique-ified relation (or unique-ified path in v18) always exists. In
cases where all RHS columns that need to be unique-ified are equated
to constants, the unique-ified relation/path for the parent table is
not built, as there are no columns left to unique-ify. Failing to
account for this can result in a SIGSEGV crash during planning.
This patch checks whether the parent's unique-ified relation or path
exists and skips unique-ification of the child relation if it does
not.
Author: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/CAMbWs49MOdLW2c+qbLHHBt8VBu=4ONpM91D19=AWeW93eFUF6A@mail.gmail.com
Backpatch-through: 18
Previously, we used LW_EXCLUSIVE in several places despite only reading
WalSummarizerCtl fields. This patch reduces the lock level to LW_SHARED
where we are only reading the shared fields.
Backpatch to 17, where wal summarization was introduced.
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/CAD21AoDdKhf_9oriEYxY-JCdF+Oe_muhca3pcdkMEdBMzyHyKw@mail.gmail.com
Backpatch-through: 17
One mechanism we have for implementing semi-joins is to de-duplicate
the output of the RHS and then treat the join as a plain inner join.
Initial construction of the join's SpecialJoinInfo identifies the
RHS columns that need to be de-duplicated, but later we may find that
some of those don't need to be handled explicitly, either because
they're known to be constant or because they are redundant with some
previous column.
Up to now, while sort-based de-duplication handled such cases well,
hash-based de-duplication didn't: we'd still hash on all of the
originally-identified columns. This is probably not a very big
deal performance-wise, but in the wake of commit a3179ab69 it can
cause planner errors. That happens when join elimination causes
recalculation of variables' attr_needed bitmapsets, and we decide
that a variable mentioned in a semijoin clause doesn't need to be
propagated up to the join level anymore.
There are a number of ways we could slice the blame for this, but the
only fix that doesn't result in pessimizing plans for loosely-related
cases is to be more careful about not hashing columns we don't
actually need to de-duplicate. We can install that consideration
into create_unique_paths in master, or the predecessor code in
create_unique_path in v18, without much refactoring.
(As follow-up work, it might be a good idea to look at more-invasive
refactoring, in hopes of preventing other bugs in this area. But
with v18 release so close, there's not time for that now, nor would
we be likely to want to put such refactoring into v18 anyway.)
Reported-by: Sergey Soloviev <sergey.soloviev@tantorlabs.ru>
Diagnosed-by: Richard Guo <guofenglinux@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/1fd1a421-4609-4d46-a1af-ab74d5de504a@tantorlabs.ru
Backpatch-through: 18
This has been done historically because of get_database_name (which
since commit cb98e6fb8f belongs in lsyscache.c/h, so let's move it
there) and get_database_oid (which is in the right place, but whose
declaration should appear in pg_database.h rather than dbcommands.h).
Clean this up.
Also, xlogreader.h and stringinfo.h are no longer needed by dbcommands.h
since commit f1fd515b39, so remove them.
Author: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/202508191031.5ipojyuaswzt@alvherre.pgsql
During an investigation into rather odd aio related errors on macos, observed
by Alexander and Konstantin, we started to wonder if bitfield access is
related to the error. At the moment it looks like it is related, we cannot
reproduce the failures when replacing the bitfields. In addition, the problem
can only be reproduced with some compiler [versions] and not everyone has been
able to reproduce the issue.
The observed problem is that, very rarely, PgAioHandle->{state,target} are in
an inconsistent state, after having been checked to be in a valid state not
long before, triggering an assertion failure. Unfortunately, this could be
caused by wrong compiler code generation or somehow of missing memory barriers
- we don't really know. In theory there should not be any concurrent write
access to the handle in the state the bug is triggered, as the handle was idle
and is just being initialized.
Separately from the bug, we observed that at least gcc and clang generate
rather terrible code for the bitfield access. Even if it's not clear if the
observed assertion failure is actually caused by the bitfield somehow, the bad
code generation alone is sufficient reason to stop using bitfields.
Therefore, replace the enum bitfields with uint8s and instead cast in each
switch statement.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reported-by: Konstantin Knizhnik <knizhnik@garret.ru>
Discussion: https://postgr.es/m/1500090.1745443021@sss.pgh.pa.us
Backpatch-through: 18
Commit d31bbfb659 removed the comment at objectNamesToOids() that
there is no locking, because that commit added locking. But to fix
all the problems, we'd still need a stronger lock. So put the comment
back with more a detailed explanation.
Co-authored-by: Noah Misch <noah@leadboat.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Discussion: https://www.postgresql.org/message-id/flat/bf72b82c-124d-4efa-a484-bb928e9494e4@eisentraut.org
This patch fixes a bug in how 'load_external_function' handles
'$libdir/ prefixes in module paths.
Previously, 'load_external_function' would unconditionally strip
'$libdir/' from the beginning of the 'filename' string. This caused
an issue when the path was nested, such as "$libdir/nested/my_lib".
Stripping the prefix resulted in a path of "nested/my_lib", which
would fail to be found by the expand_dynamic_library_name function
because the original '$libdir' macro was removed.
To fix this, the code now checks for the presence of an additional
directory separator ('/' or '\') after the '$libdir/' prefix. The
prefix is only stripped if the remaining string does not contain a
separator. This ensures that simple filenames like '"$libdir/my_lib"'
are correctly handled, while nested paths are left intact for
'expand_dynamic_library_name' to process correctly.
Reported-by: Dilip Kumar <dilipbalaut@gmail.com>
Co-authored-by: Matheus Alcantara <matheusssilv97@gmail.com>
Co-authored-by: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: Srinath Reddy Sadipiralla <srinath2133@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAFiTN-uKNzAro4tVwtJhF1UqcygfJ%2BR%2BRL%3Db-_ZMYE3LdHoGhA%40mail.gmail.com
Commit 4b754d6c1 introduced the concept of an excludeOnly scan key,
which cannot select matching index entries but can reject
non-matching tuples, for example a tsquery such as '!term'. There are
poorly-documented assumptions that such scan keys do not appear as the
first scan key. ginNewScanKey did nothing to ensure that, however,
with the result that certain GIN index searches could go into an
infinite loop while apparently-equivalent queries with the clauses in
a different order were fine.
Fix by teaching ginNewScanKey to place all excludeOnly scan keys
after all not-excludeOnly ones. So far as we know at present,
it might be sufficient to avoid the case where the very first
scan key is excludeOnly; but I'm not very convinced that there
aren't other dependencies on the ordering.
Bug: #19031
Reported-by: Tim Wood <washwithcare@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19031-0638148643d25548@postgresql.org
Backpatch-through: 13
The CHECK_FOR_INTERRUPTS call in gingetbitmap turns out to be
inadequate to prevent a long uninterruptible loop, because
we now know a case where looping occurs within scanGetItem.
While the next patch will fix the bug that caused that, it
seems foolish to assume that no similar patterns are possible.
Let's do the CFI within scanGetItem's retry loop, instead.
This demonstrably allows canceling out of the loop exhibited
in bug #19031.
Bug: #19031
Reported-by: Tim Wood <washwithcare@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19031-0638148643d25548@postgresql.org
Backpatch-through: 13
The Self-Join Elimination SJE feature messes up keeping and removing RowMark's
in remove_self_joins_one_group(). That didn't lead to user-level error,
because the planned RowMark is only used to reference a rtable entry in later
execution stages. An RTE entry for keeping and removing relations is
identical and refers to the same relation OID.
To reduce confusion and prevent future issues, this commit cleans up the code
and fixes the incorrect behaviour. Furthermore, it includes sanity checks in
setrefs.c on existing non-null RTE and RelOptInfo entries for each RowMark.
Discussion: https://postgr.es/m/18c6bd6c-6d2a-419a-b0da-dfedef34b585%40gmail.com
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Greg Sabino Mullane <htamfids@gmail.com>
Backpatch-through: 18
Rename inner and outer to rrel and krel, respectively, to highlight their
connection to r and k indexes. For the same reason, rename imark and omark
to rmark and kmark.
Discussion: https://postgr.es/m/18c6bd6c-6d2a-419a-b0da-dfedef34b585%40gmail.com
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Greg Sabino Mullane <htamfids@gmail.com>
Backpatch-through: 18
This reverts commit bc22dc0e0d.
It appears that conditional variables are not suitable for use inside
critical sections. If WaitLatch()/WaitEventSetWaitBlock() face postmaster
death, they exit, releasing all locks instead of PANIC. In certain
situations, this leads to data corruption.
Reported-by: Andrey Borodin <x4mmm@yandex-team.ru>
Discussion: https://postgr.es/m/B3C69B86-7F82-4111-B97F-0005497BB745%40yandex-team.ru
Reviewed-by: Andrey Borodin <x4mmm@yandex-team.ru>
Reviewed-by: Aleksander Alekseev <aleksander@tigerdata.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Yura Sokolov <y.sokolov@postgrespro.ru>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Backpatch-through: 18
Commit 1585ff7387 changed GetTransactionSnapshot() to throw an error
if it's called during logical decoding, instead of returning the
historic snapshot. I made that change for extra protection, because a
historic snapshot can only be used to access catalog tables while
GetTransactionSnapshot() is usually called when you're executing
arbitrary queries. You might get very subtle visibility problems if
you tried to use the historic snapshot for arbitrary queries.
There's no built-in code in PostgreSQL that calls
GetTransactionSnapshot() during logical decoding, but it turns out
that the pglogical extension does just that, to evaluate row filter
expressions. You would get weird results if the row filter runs
arbitrary queries, but it is sane as long as you don't access any
non-catalog tables. Even though there are no checks to enforce that in
pglogical, a typical row filter expression does not access any tables
and works fine. Accessing tables marked with the user_catalog_table =
true option is also OK.
To fix pglogical with row filters, and any other extensions that might
do similar things, revert GetTransactionSnapshot() to return a
historic snapshot during logical decoding.
To try to still catch the unsafe usage of historic snapshots, add
checks in heap_beginscan() and index_beginscan() to complain if you
try to use a historic snapshot to scan a non-catalog table. We're very
close to the version 18 release however, so add those new checks only
in master.
Backpatch-through: 18
Reported-by: Noah Misch <noah@leadboat.com>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://www.postgresql.org/message-id/20250809222338.cc.nmisch@google.com
Reduce from ShareLock to ShareUpdateExclusivelock. Validation during
ALTER DOMAIN ... ADD CONSTRAINT keeps using ShareLock.
Example:
create domain d1 as int;
create table t (a d1);
alter domain d1 add constraint cc10 check (value > 10) not valid;
begin;
alter domain d1 validate constraint cc10;
-- another session
insert into t values (8);
Now we should still be able to perform DML operations on table t while
the domain constraint is being validated. The equivalent works
already on table constraints.
Author: jian he <jian.universality@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: wenhui qiu <qiuwenhuifx@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CACJufxHz92A88NLRTA2msgE2dpXpE-EoZ2QO61od76-6bfqurA%40mail.gmail.com
This code was relying on "long", which is signed 8 bytes everywhere
except on Windows where it is 4 bytes, that could potentially expose it
to overflows, even if the current uses in the code are fine as far as I
know. This code is now able to rely on the same sizeof() variable
everywhere, with int64. long was used for sizes, partition counts and
entry counts.
Some callers of the dynahash.c routines used long declarations, that can
be cleaned up to use int64 instead. There was one shortcut based on
SIZEOF_LONG, that can be removed. long is entirely removed from
dynahash.c and hsearch.h.
Similar work was done in b1e5c9fa9a.
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Discussion: https://postgr.es/m/aKQYp-bKTRtRauZ6@paquier.xyz
Temporary relations may share the same RelFileNumber with a permanent
relation, or other temporary relations associated with other sessions.
Being able to uniquely identify a temporary relation would require
RelidByRelfilenumber() to know about the proc number of the temporary
relation it wants to identify, something it is not designed for since
its introduction in f01d1ae3a1.
There are currently three callers of RelidByRelfilenumber():
- autoprewarm.
- Logical decoding, reorder buffer.
- pg_filenode_relation(), that attempts to find a relation OID based on
a tablespace OID and a RelFileNumber.
This makes the situation problematic particularly for the first two
cases, leading to the possibility of random ERRORs due to
inconsistencies that temporary relations can create in the cache
maintained by RelidByRelfilenumber(). The third case should be less of
an issue, as I suspect that there are few direct callers of
pg_filenode_relation().
The window where the ERRORs are happen is very narrow, requiring an OID
wraparound to create a lookup conflict in RelidByRelfilenumber() with a
temporary table reusing the same OID as another relation already cached.
The problem is easier to reach in workloads with a high OID consumption
rate, especially with a higher number of temporary relations created.
We could get pg_filenode_relation() and RelidByRelfilenumber() to work
with temporary relations if provided the means to identify them with an
optional proc number given in input, but the years have also shown that
we do not have a use case for it, yet. Note that this could not be
backpatched if pg_filenode_relation() needs changes. It is simpler to
ignore temporary relations.
Reported-by: Shenhao Wang <wangsh.fnst@fujitsu.com>
Author: Vignesh C <vignesh21@gmail.com>
Reviewed-By: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-By: Robert Haas <robertmhaas@gmail.com>
Reviewed-By: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-By: Takamichi Osumi <osumi.takamichi@fujitsu.com>
Reviewed-By: Michael Paquier <michael@paquier.xyz>
Reviewed-By: Masahiko Sawada <sawada.mshk@gmail.com>
Reported-By: Shenhao Wang <wangsh.fnst@fujitsu.com>
Discussion: https://postgr.es/m/bbaaf9f9-ebb2-645f-54bb-34d6efc7ac42@fujitsu.com
Backpatch-through: 13
The result of pgaio_io_get_id() was being assigned to a mix of int and
uint32 variables. This fixes it to use int consistently, which seems
the most correct. Also change the queue empty special value in
method_worker.c to -1 from UINT32_MAX.
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/70c784b3-f60b-4652-b8a6-75e5f051243e%40eisentraut.org
Replication slot synchronization (sync_replication_slots = on)
requires wal_level to be logical. This commit prevents the server
from starting if sync_replication_slots is enabled but wal_level
is set to minimal or replica.
Failing early during startup helps users catch invalid configurations
immediately, which is important because changing wal_level requires
a server restart.
Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Shveta Malik <shveta.malik@gmail.com>
Discussion: https://postgr.es/m/CAH0PTU_pc3oHi__XESF9ZigCyzai1Mo3LsOdFyQA4aUDkm01RA@mail.gmail.com
If we error out during execution of a SQL-language function, we will
often leave behind non-null pointers in its SQLFunctionCache's cplan
and eslist fields. This is problematic if the SQLFunctionCache is
re-used, because those pointers will point at resources that were
released during error cleanup. This problem escaped detection so far
because ordinarily we won't re-use an FmgrInfo+SQLFunctionCache struct
after a query error. However, in the rather improbable case that
someone implements an opclass support function in SQL language, there
will be long-lived FmgrInfos for it in the relcache, and then the
problem is reachable after the function throws an error.
To fix, add a flag to SQLFunctionCache that tracks whether execution
escapes out of fmgr_sql, and clear out the relevant fields during
init_sql_fcache if so. (This is going to need more thought if we ever
try to share FMgrInfos across threads; but it's very far from being
the only problem such a project will encounter, since many functions
regard fn_extra as being query-local state.)
This broke at commit 0313c5dc6; before that we did not try to re-use
SQLFunctionCache state across calls. Hence, back-patch to v18.
Bug: #19026
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19026-90aed5e71d0c8af3@postgresql.org
Backpatch-through: 18
In refuseDupeIndexAttach(), change from
errdetail("Another index is already attached for partition \"%s\"."...)
to
errdetail("Another index \"%s\" is already attached for partition \"%s\"."...)
so we can easily understand which index is already attached for
partition \"%s\".
Author: Jian He <jian.universality@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://www.postgresql.org/message-id/flat/CACJufxGBfykJ_1ztk9T%2BL_gLmkOSOF%2BmL9Mn4ZPydz-rh%3DLccQ%40mail.gmail.com
Some replication slot manipulations (logical decoding via SQL,
advancing) were failing an assertion when releasing a slot in
single-user mode, because active_pid was not set in a ReplicationSlot
when its slot is acquired.
ReplicationSlotAcquire() has some logic to be able to work with the
single-user mode. This commit sets ReplicationSlot->active_pid to
MyProcPid, to let the slot-related logic fall-through, considering the
single process as the one holding the slot.
Some TAP tests are added for various replication slot functions with the
single-user mode, while on it, for slot creation, drop, advancing, copy
and logical decoding with multiple slot types (temporary, physical vs
logical). These tests are skipped on Windows, as direct calls of
postgres --single would fail on permission failures. There is no
platform-specific behavior that needs to be checked, so living with this
restriction should be fine. The CI is OK with that, now let's see what
the buildfarm tells.
Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Paul A. Jungwirth <pj@illuminatedcomputing.com>
Reviewed-by: Mutaamba Maasha <maasha@gmail.com>
Discussion: https://postgr.es/m/OSCPR01MB14966ED588A0328DAEBE8CB25F5FA2@OSCPR01MB14966.jpnprd01.prod.outlook.com
Backpatch-through: 13
This comment mentions that pg_buffercache locks all buffer
partitions simultaneously, but it hasn't done so since v10.
Oversight in commit 6e654546fb.
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/aKTuAHVEuYCUmmIy%40nathan
The DROP SUBSCRIPTION command performs several operations: it stops the
subscription workers, removes subscription-related entries from system
catalogs, and deletes the replication slot on the publisher server.
Previously, this command acquired an AccessExclusiveLock on
pg_subscription before initiating these steps.
However, while holding this lock, the command attempts to connect to the
publisher to remove the replication slot. In cases where the connection is
made to a newly created database on the same server as subscriber, the
cache-building process during connection tries to acquire an
AccessShareLock on pg_subscription, resulting in a self-deadlock.
To resolve this issue, we reduce the lock level on pg_subscription during
DROP SUBSCRIPTION from AccessExclusiveLock to RowExclusiveLock. Earlier,
the higher lock level was used to prevent the launcher from starting a new
worker during the drop operation, as a restarted worker could become
orphaned.
Now, instead of relying on a strict lock, we acquire an AccessShareLock on
the specific subscription being dropped and re-validate its existence
after acquiring the lock. If the subscription is no longer valid, the
worker exits gracefully. This approach avoids the deadlock while still
ensuring that orphan workers are not created.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 13
Discussion: https://postgr.es/m/18988-7312c868be2d467f@postgresql.org
This provides a single entry point to access some information about the
state of MultiXacts, able to return some data about multixacts offsets
and counts. Originally this function was only able to return some
information about the number of multixacts and multixact members,
extended here to provide some data about the oldest multixact ID in use
and the oldest offset, if known.
This change has been proposed in a patch that aims at providing more
monitoring capabilities for multixacts, and it is useful on its own.
GetMultiXactInfo() is added to multixact.h, becoming available for
out-of-core code.
Extracted from a larger patch by the same author.
Author: Naga Appani <nagnrik@gmail.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CA+QeY+AAsYK6WvBW4qYzHz4bahHycDAY_q5ECmHkEV_eB9ckzg@mail.gmail.com
This pointer was not used after its last update. This variable
assignment was most likely a vestige artifact of the earlier versions of
the patch set that have led to 5891c7a8ed.
This pointer update is useless, so let's remove it. It removes one call
to pgstat_dsa_init_size(), making the code slightly easier to grasp.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/aKLsu2sdpnyeuSSc@ip-10-97-1-34.eu-west-3.compute.internal
Now that the only call to relation_has_unique_index_for() that
supplied an exprlist and oprlist has been removed, the loop handling
those lists is effectively dead code. This patch removes that loop
and simplifies the function accordingly.
Author: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/CAMbWs4-EBnaRvEs7frTLbsXiweSTUXifsteF-d3rvv01FKO86w@mail.gmail.com
There are two implementation techniques for semijoins: one uses the
JOIN_SEMI jointype, where the executor emits at most one matching row
per left-hand side (LHS) row; the other unique-ifies the right-hand
side (RHS) and then performs a plain inner join.
The latter technique currently has some drawbacks related to the
unique-ification step.
* Only the cheapest-total path of the RHS is considered during
unique-ification. This may cause us to miss some optimization
opportunities; for example, a path with a better sort order might be
overlooked simply because it is not the cheapest in total cost. Such
a path could help avoid a sort at a higher level, potentially
resulting in a cheaper overall plan.
* We currently rely on heuristics to choose between hash-based and
sort-based unique-ification. A better approach would be to generate
paths for both methods and allow add_path() to decide which one is
preferable, consistent with how path selection is handled elsewhere in
the planner.
* In the sort-based implementation, we currently pay no attention to
the pathkeys of the input subpath or the resulting output. This can
result in redundant sort nodes being added to the final plan.
This patch improves semijoin planning by creating a new RelOptInfo for
the RHS rel to represent its unique-ified version. It then generates
multiple paths that represent elimination of distinct rows from the
RHS, considering both a hash-based implementation using the cheapest
total path of the original RHS rel, and sort-based implementations
that either exploit presorted input paths or explicitly sort the
cheapest total path. All resulting paths compete in add_path(), and
those deemed worthy of consideration are added to the new RelOptInfo.
Finally, the unique-ified rel is joined with the other side of the
semijoin using a plain inner join.
As a side effect, most of the code related to the JOIN_UNIQUE_OUTER
and JOIN_UNIQUE_INNER jointypes -- used to indicate that the LHS or
RHS path should be made unique -- has been removed. Besides, the
T_Unique path now has the same meaning for both semijoins and upper
DISTINCT clauses: it represents adjacent-duplicate removal on
presorted input. This patch unifies their handling by sharing the
same data structures and functions.
This patch also removes the UNIQUE_PATH_NOOP related code along the
way, as it is dead code -- if the RHS rel is provably unique, the
semijoin should have already been simplified to a plain inner join by
analyzejoins.c.
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Alexandra Wang <alexandra.wang.oss@gmail.com>
Reviewed-by: wenhui qiu <qiuwenhuifx@gmail.com>
Discussion: https://postgr.es/m/CAMbWs4-EBnaRvEs7frTLbsXiweSTUXifsteF-d3rvv01FKO86w@mail.gmail.com
Two header declarations were related to SQL-callable functions, that
should have been cleaned up in df9133fa63. Some more includes can be
removed on closer inspection, so let's clean up these as well, while on
it.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/345438.1755524834@sss.pgh.pa.us
This existed in a semi broken stated from be0a66666 until 296cba276.
Recent discussion has questioned the value of having this at all as it
only outputs static information from various of the hash table's
properties when the hash table is created.
Author: Hayato Kuroda (Fujitsu) <kuroda.hayato@fujitsu.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/OSCPR01MB1496650D03FA0293AB9C21416F534A@OSCPR01MB14966.jpnprd01.prod.outlook.com
Previously this was being output to stderr. This commit adjusts things
to use elog(DEBUG4). Here we also adjust the format of the message to
add the hash table name and also put the message on a single line. This
should make grepping the logs for this information easier.
Also get rid of the global hash table statistics. This seems very dated
and didn't fit very well with trying to put all the statistics for a
specific hash table on a single log line.
The main aim here is to allow it so we can have at least one buildfarm
member build with HASH_STATISTICS to help prevent future changes from
breaking things in that area. ca3891251 recently fixed some issues
here.
In passing, switch to using uint64 data types rather than longs for the
usage counters. The long type is 32 bits on some platforms we support.
Author: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAApHDvoccvJ9CG5zx+i-EyCzJbcL5K=CzqrnL_YN59qaL5hiaw@mail.gmail.com
Input with zero length can result in a buffer underflow when
accessing *(num + (len - 1)), as (len - 1) would produce a negative
index. Add an assertion for zero-length input to prevent it.
This was found by ALT Linux Team.
Reviewing the call sites shows that get_th() currently cannot be
applied to an empty string: it is always called on a string containing
a number we've just printed. Therefore, an assertion rather than a
user-facing error message is sufficient.
Co-authored-by: Alexander Kuznetsov <kuznetsovam@altlinux.org>
Discussion: https://www.postgresql.org/message-id/flat/e22df993-cdb4-4d0a-b629-42211ebed582@altlinux.org
A patch is under discussion to add more SQL capabilities related to
multixacts, and this move avoids bloating the file more than necessary.
This affects pg_get_multixact_members(). A side effect of this move is
the requirement to add mxstatus_to_string() to multixact.h.
Extracted from a larger patch by the same author, tweaked by me.
Author: Naga Appani <nagnrik@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: https://postgr.es/m/CA+QeY+AAsYK6WvBW4qYzHz4bahHycDAY_q5ECmHkEV_eB9ckzg@mail.gmail.com
init_params() sets up "last_value" and "is_called" for a sequence
relation holdind its metadata, based on the sequence properties in
pg_sequences. "log_cnt" is the third property that can be updated in
this routine for FormData_pg_sequence_data, tracking when WAL records
should be generated for a sequence after nextval() iterations. This
routine is called when creating or altering a sequence.
This commit refactors init_params() to not depend anymore on
FormData_pg_sequence_data, removing traces of it in sequence.c, making
easier the manipulation of metadata related to sequences. The knowledge
about "log_cnt" is replaced with a more general "reset_state" flag, to
let the caller know if the sequence state should be reset. In the case
of in-core sequences, this relates to WAL logging. We still need to
depend on FormData_pg_sequence.
Author: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/ZWlohtKAs0uVVpZ3@paquier.xyz
When extracting a timestamp from a UUIDv7, a conversion from
milliseconds to microseconds was using the incorrect constant
NS_PER_US instead of US_PER_MS. Although both constants have the same
value, this fix improves code clarity by using the semantically
correct constant.
Backpatch to v18, where UUIDv7 was introduced.
Author: Erik Nordström <erik@tigerdata.com>
Reviewed-by: Andrey Borodin <x4mmm@yandex-team.ru>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/CACAa4V+i07eaP6h4MHNydZeX47kkLPwAg0sqe67R=M5tLdxNuQ@mail.gmail.com
Backpatch-through: 18
bms_prev_member() could attempt to access memory outside of the words[]
array in cases where the prevbit was a number < -1 or > a->nwords *
BITS_PER_BITMAPWORD + 1.
Here we add the Asserts to help draw attention to bogus callers so we're
more likely to catch them during development.
In passing, fix wording of bms_prev_member's header comment which talks
about how we expect the callers to ensure only valid prevbit values are
used.
Author: Greg Burd <greg@burd.me>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/2000A717-1FFE-4031-827B-9330FB2E9065%40getmailspring.com
Doing that seems rather random and unnecessary. This commit removes
those and fixes fallout, which is pretty minimal. We do need to add a
forward declaration of struct TM_IndexDeleteOp (whose full definition
appears in tableam.h) so that _bt_delitems_delete_check()'s declaration
can use it.
Author: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/202508051109.lzk3lcuzsaxo@alvherre.pgsql
Make sure the memory allocated by make_absolute_path() is freed
when SelectConfigFiles() fails. Since all the callers will exit
immediately in that case, there's no practical gain here, but
silencing Valgrind leak complaints seems useful. In any case,
it was inconsistent that only one of the failure exits did this.
Author: Aleksander Alekseev <aleksander@tigerdata.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAJ7c6TMByXE8dc7zDvDWTQjk6o-XXAdRg_RAg5CBaUOgFPV3LQ%40mail.gmail.com
This function uses an argument named "maxsize" that is only used in
assertions, being set once outside the assertion area. Recent gcc
versions with -Wunused-but-set-parameter complain about a warning when
building without assertions enabled, because of that.
In order to fix this issue, PG_USED_FOR_ASSERTS_ONLY is added to the
function argument of SerializeClientConnectionInfo(), which is the first
time we are doing so in the tree. The CI is fine with the change, but
let's see what the buildfarm has to say on the matter.
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Jacob Champion <jchampion@postgresql.org>
Discussion: https://postgr.es/m/pevajesswhxafjkivoq3yvwxga77tbncghlf3gq5fvchsvfuda@6uivg25sb3nx
Backpatch-through: 16
Commit 2633dae2e4 standardized LSN formatting but mistakenly changed
the logical snapshot filename format in SnapBuildSnapshotExists() from
"%X-%X.snap" to "%08X-%08X.snap". Other code still used the original
"%X-%X.snap" format, causing the replication slot synchronization worker
to fail to find existing snapshot files and produce excessive log messages.
This commit restores the original "%X-%X.snap" format
in SnapBuildSnapshotExists() to resolve the issue.
Author: Shveta Malik <shveta.malik@gmail.com>
Discussion: https://postgr.es/m/CAHGQGwHuHPB-ucAk_Tq3uSs4Fdziu1Jp_AA_RD3m5Ycky7m48w@mail.gmail.com
Remove conditionally-compiled code for the other case.
Replace uses of FLOAT8PASSBYVAL with constant "true", mainly because
it was quite confusing in cases where the type we were dealing with
wasn't float8.
I left the associated pg_control and Pg_magic_struct fields in place.
Perhaps we should get rid of them, but it would save little, so it
doesn't seem worth thinking hard about the compatibility implications.
I just labeled them "vestigial" in places where that seemed helpful.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/1749799.1752797397@sss.pgh.pa.us
Remove conditionally-compiled code for smaller Datum widths,
and simplify comments that describe cases no longer of interest.
I also fixed up a few more places that were not using
DatumGetIntXX where they should, and made some cosmetic
adjustments such as using sizeof(int64) not sizeof(Datum)
in places where that fit better with the surrounding code.
One thing I remembered while preparing this part is that SP-GiST
stores pass-by-value prefix keys as Datums, so that the on-disk
representation depends on sizeof(Datum). That's even more
unfortunate than the existing commentary makes it out to be,
because now there is a hazard that the change of sizeof(Datum)
will break SP-GiST indexes on 32-bit machines. It appears that
there are no existing SP-GiST opclasses that are actually
affected; and if there are some that I didn't find, the number
of installations that are using them on 32-bit machines is
doubtless tiny. So I'm proceeding on the assumption that we
can get away with this, but it's something to worry about.
(gininsert.c looks like it has a similar problem, but it's okay
because the "tuples" it's constructing are just transient data
within the tuplesort step. That's pretty poorly documented
though, so I added some comments.)
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/1749799.1752797397@sss.pgh.pa.us
This patch makes sizeof(Datum) be 8 on all platforms including
32-bit ones. The objective is to allow USE_FLOAT8_BYVAL to be true
everywhere, and in consequence to remove a lot of code that is
specific to pass-by-reference handling of float8, int8, etc. The
code for abbreviated sort keys can be simplified similarly. In this
way we can reduce the maintenance effort involved in supporting 32-bit
platforms, without going so far as to actually desupport them. Since
Datum is strictly an in-memory concept, this has no impact on on-disk
storage, though an initdb or pg_upgrade will be needed to fix affected
catalog entries.
We have required platforms to support [u]int64 for ages, so this
breaks no supported platform. We can expect that this change will
make 32-bit builds a bit slower and more memory-hungry, although being
able to use pass-by-value handling of 8-byte types may buy back some
of that. But we stopped optimizing for 32-bit cases a long time ago,
and this seems like just another step on that path.
This initial patch simply forces the correct type definition and
USE_FLOAT8_BYVAL setting, and cleans up a couple of minor compiler
complaints that ensued. This is sufficient for testing purposes.
In the wake of a bunch of Datum-conversion cleanups by Peter
Eisentraut, this now compiles cleanly with gcc on a 32-bit platform.
(I'd only tested the previous version with clang, which it turns out
is less picky than gcc about width-changing coercions.)
There is a good deal of now-dead code that I'll remove in separate
follow-up patches.
A catversion bump is required because this affects initial catalog
contents (on 32-bit machines) in two ways: pg_type.typbyval changes
for some built-in types, and Const nodes in stored views/rules will
now have 8 bytes not 4 for pass-by-value types.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/1749799.1752797397@sss.pgh.pa.us
It turns out that on some platforms (at least current macOS, NetBSD,
OpenBSD) semget(2) will return EINVAL if there is a pre-existing
semaphore set with the same key and too few semaphores. Our code
expects EEXIST in that case and treats EINVAL as a hard failure,
resulting in failure during initdb or postmaster start.
POSIX does document EINVAL for too-few-semaphores-in-set, and is
silent on its priority relative to EEXIST, so this behavior arguably
conforms to spec. Nonetheless it's quite problematic because EINVAL
is also documented to mean that nsems is greater than the system's
limit on the number of semaphores per set (SEMMSL). If that is
where the problem lies, retrying would just become an infinite loop.
To resolve this contradiction, retry after EINVAL, but also install a
loop limit that will make us give up regardless of the specific errno
after trying 1000 different keys. (1000 is a pretty arbitrary number,
but it seems like it should be sufficient.) I like this better than
the previous infinite-looping behavior, since it will also keep us out
of trouble if (say) we get EACCES due to a system-level permissions
problem rather than anything to do with a specific semaphore set.
This problem has only been observed in the field in PG 17, which uses
a higher nsems value than other branches (cf. 38da05346, 810a8b1c8).
That makes it possible to get the failure if a new v17 postmaster
has a key collision with an existing postmaster of another branch.
In principle though, we might see such a collision against a semaphore
set created by some other application, in which case all branches are
vulnerable on these platforms. Hence, backpatch.
Reported-by: Gavin Panella <gavinpanella@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CALL7chmzY3eXHA7zHnODUVGZLSvK3wYCSP0RmcDFHJY8f28Q3g@mail.gmail.com
Backpatch-through: 13
fb9f955025 optimized code generation by using specialized variants of
ExecSeqScan* for [not] having a qual, projection etc. This allowed the
compiler to optimize the code out the code for qual / projection. However, as
observed by David Rowley at the time, the compiler couldn't prove the
opposite, i.e. that the qual etc *are* present.
By using pg_assume(), introduced in d65eb5b1b8, we can tell the compiler that
the relevant variables are non-null.
This reduces the code size to a surprising degree and seems to lead to a small
but reproducible performance gain.
Reviewed-by: Amit Langote <amitlangote09@gmail.com> Discussion:
https://postgr.es/m/CA+HiwqFk-MbwhfX_kucxzL8zLmjEt9MMcHi2YF=DyhPrSjsBEA@mail.gmail.com
Without using stamp files, meson lists the generated headers as the dependency
for every .c file, bloating build.ninja by more than 2x. Processing all the
dependencies also increases the time to generate build.ninja.
The immediate benefit is that this makes re-configuring and clean builds a bit
faster. The main motivation however is that I have other patches that
introduce additional build targets that further would increase the size of
build.ninja, making re-configuring more noticeably slower.
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/cgkdgvzdpinkacf4v33mky7tbmk467oda5dd4dlmucjjockxzi@xkqfvjoq4uiy
Commit e2d4ef8de8 (the fix for CVE-2017-7484) added security checks
to the selectivity estimation functions to prevent them from running
user-supplied operators on data obtained from pg_statistic if the user
lacks privileges to select from the underlying table. In cases
involving inheritance/partitioning, those checks were originally
performed against the child RTE (which for plain inheritance might
actually refer to the parent table). Commit 553d2ec271 then extended
that to also check the parent RTE, allowing access if the user had
permissions on either the parent or the child. It turns out, however,
that doing any checks using the child RTE is incorrect, since
securityQuals is set to NULL when creating an RTE for an inheritance
child (whether it refers to the parent table or the child table), and
therefore such checks do not correctly account for any RLS policies or
security barrier views. Therefore, do the security checks using only
the parent RTE. This is consistent with how RLS policies are applied,
and the executor's ACL checks, both of which use only the parent
table's permissions/policies. Similar checks are performed in the
extended stats code, so update that in the same way, centralizing all
the checks in a new function.
In addition, note that these checks by themselves are insufficient to
ensure that the user has access to the table's data because, in a
query that goes via a view, they only check that the view owner has
permissions on the underlying table, not that the current user has
permissions on the view itself. In the selectivity estimation
functions, there is no easy way to navigate from underlying tables to
views, so add permissions checks for all views mentioned in the query
to the planner startup code. If the user lacks permissions on a view,
a permissions error will now be reported at planner-startup, and the
selectivity estimation functions will not be run.
Checking view permissions at planner-startup in this way is a little
ugly, since the same checks will be repeated at executor-startup.
Longer-term, it might be better to move all the permissions checks
from the executor to the planner so that permissions errors can be
reported sooner, instead of creating a plan that won't ever be run.
However, such a change seems too far-reaching to be back-patched.
Back-patch to all supported versions. In v13, there is the added
complication that UPDATEs and DELETEs on inherited target tables are
planned using inheritance_planner(), which plans each inheritance
child table separately, so that the selectivity estimation functions
do not know that they are dealing with a child table accessed via its
parent. Handle that by checking access permissions on the top parent
table at planner-startup, in the same way as we do for views. Any
securityQuals on the top parent table are moved down to the child
tables by inheritance_planner(), so they continue to be checked by the
selectivity estimation functions.
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Noah Misch <noah@leadboat.com>
Backpatch-through: 13
Security: CVE-2025-8713
The internal queue of buffers could become corrupted in a rare edge case
that failed to invalidate an entry, causing a stale buffer to be
"forwarded" to StartReadBuffers(). This is a simple fix for the
immediate problem.
A small API change might be able to remove this and related fragility
entirely, but that will have to wait a bit.
Defect in commit ed0b87ca.
Bug: 19006
Backpatch-through: 18
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Xuneng Zhou <xunengzhou@gmail.com>
Discussion: https://postgr.es/m/19006-80fcaaf69000377e%40postgresql.org
Fix a couple more places where an explicit Datum conversion
is needed (not clear how we missed these in ff89e182d and
previous commits).
Replace the minority usage "(Datum) NULL" with "(Datum) 0".
The former depends on the assumption that Datum is the same
width as Pointer, the latter doesn't. Anyway consistency
is a good thing.
This is, I believe, the last of the notational mop-up needed
before we can consider changing Datum to uint64 everywhere.
It's also important cleanup for more aggressive ideas such
as making Datum a struct.
Discussion: https://postgr.es/m/1749799.1752797397@sss.pgh.pa.us
Discussion: https://postgr.es/m/8246d7ff-f4b7-4363-913e-827dadfeb145@eisentraut.org
Add various missing conversions from and to Datum. The previous code
mostly relied on implicit conversions or its own explicit casts
instead of using the correct DatumGet*() or *GetDatum() functions.
We think these omissions are harmless. Some actual bugs that were
discovered during this process have been committed
separately (80c758a2e1, fd2ab03fea).
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/8246d7ff-f4b7-4363-913e-827dadfeb145%40eisentraut.org
This function is called from ATExecAttachPartition/ATExecAddInherit,
which prevent tables with row-level triggers with transition tables from
becoming partitions or inheritance children, to check if there is such a
trigger on the given table, but failed to check if a found trigger is
row-level, causing the caller functions to needlessly prevent a table
with only a statement-level trigger with transition tables from becoming
a partition or inheritance child. Repair.
Oversight in commit 501ed02cf.
Author: Etsuro Fujita <etsuro.fujita@gmail.com>
Discussion: https://postgr.es/m/CAPmGK167mXzwzzmJ_0YZ3EZrbwiCxtM1vogH_8drqsE6PtxRYw%40mail.gmail.com
Backpatch-through: 13
Commit 9e6104c66 disallowed transition tables on foreign tables, but
failed to account for cases where a foreign table is a child table of a
partitioned/inherited table on which transition tables exist, leading to
incorrect transition tuples collected from such foreign tables for
queries on the parent table triggering transition capture. This
occurred not only for inherited UPDATE/DELETE but for partitioned INSERT
later supported by commit 3d956d956, which should have handled it at
least for the INSERT case, but didn't.
To fix, modify ExecAR*Triggers to throw an error if the given relation
is a foreign table requesting transition capture. Also, this commit
fixes make_modifytable so that in case of an inherited UPDATE/DELETE
triggering transition capture, FDWs choose normal operations to modify
child foreign tables, not DirectModify; which is needed because they
would otherwise skip the calls to ExecAR*Triggers at execution, causing
unexpected behavior.
Author: Etsuro Fujita <etsuro.fujita@gmail.com>
Reviewed-by: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/CAPmGK14QJYikKzBDCe3jMbpGENnQ7popFmbEgm-XTNuk55oyHg%40mail.gmail.com
Backpatch-through: 13
Dropping twice a pgstats entry should not happen, and the error report
generated was missing the "generation" counter (tracking when an entry
is reused) that has been added in 818119afcc.
Like d92573adcb, backpatch down to v15 where this information is
useful to have, to gather more information from instances where the
problem shows up. A report has shown that this error path has been
reached on a standby based on 17.3, for a relation stats entry and an
OID close to wraparound.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/CAN4RuQvYth942J2+FcLmJKgdpq6fE5eqyFvb_PuskxF2eL=Wzg@mail.gmail.com
Backpatch-through: 15
This adds a few more functions to int128.h, allowing more of numeric.c
to use 128-bit integers on all platforms.
Specifically, int64_div_fast_to_numeric() and the following aggregate
functions can now use 128-bit integers for improved performance on all
platforms, rather than just platforms with native support for int128:
- SUM(int8)
- AVG(int8)
- STDDEV_POP(int2 or int4)
- STDDEV_SAMP(int2 or int4)
- VAR_POP(int2 or int4)
- VAR_SAMP(int2 or int4)
In addition to improved performance on platforms lacking native
128-bit integer support, this significantly simplifies this numeric
code by allowing a lot of conditionally compiled code to be deleted.
A couple of numeric functions (div_var_int64() and sqrt_var()) still
contain conditionally compiled 128-bit integer code that only works on
platforms with native 128-bit integer support. Making those work more
generally would require rolling our own higher precision 128-bit
division, which isn't supported for now.
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
Reviewed-by: John Naylor <johncnaylorls@gmail.com>
Discussion: https://postgr.es/m/CAEZATCWgBMc9ZwKMYqQpaQz2X6gaamYRB+RnMsUNcdMcL2Mj_w@mail.gmail.com
Use Min(NBuffers, MAX_CHECKPOINT_REQUESTS) instead of NBuffers in
CheckpointerShmemSize() to match the actual array size limit set in
CheckpointerShmemInit(). This prevents wasting shared memory when
NBuffers > MAX_CHECKPOINT_REQUESTS. Also, fix the comment.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/1439188.1754506714%40sss.pgh.pa.us
Author: Xuneng Zhou <xunengzhou@gmail.com>
Co-authored-by: Alexander Korotkov <aekorotkov@gmail.com>
The code used a PG_RETURN_TIMESTAMPTZ() where the return type is
TimestampTz and not a Datum.
On 64-bit systems, there is no effect since this just ends up casting
64-bit integers back and forth. On 32-bit systems, timestamptz is
pass-by-reference. PG_RETURN_TIMESTAMPTZ() allocates new memory and
returns the address, meaning that the caller could interpret this as a
timestamp value.
The effect is using "date_trunc(..., 'infinity'::timestamptz) will
return random values (instead of the correct return value 'infinity').
Bug introduced in commit d85ce012f9.
Author: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/2d320b6f-b4af-4fbc-9eec-5d0fa15d187b@eisentraut.org
Discussion: https://postgr.es/m/4bf60a84-2862-4a53-acd5-8eddf134a60e@eisentraut.org
Backpatch-through: 18
This commit makes use of the existing PqMsg_* macros in more places
and adds new PqReplMsg_* and PqBackupMsg_* macros for use in
special replication and backup messages, respectively.
Author: Dave Cramer <davecramer@gmail.com>
Co-authored-by: Fabrízio de Royes Mello <fabriziomello@gmail.com>
Reviewed-by: Jacob Champion <jacob.champion@enterprisedb.com>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed-by: Euler Taveira <euler@eulerto.com>
Discussion: https://postgr.es/m/aIECfYfevCUpenBT@nathan
Discussion: https://postgr.es/m/CAFcNs%2Br73NOUb7%2BqKrV4HHEki02CS96Z%2Bx19WaFgE087BWwEng%40mail.gmail.com
The name "namspace" looks like a typo, but it was presumably meant
to avoid using the "namespace" C++ keyword. This commit renames
the parameter to "nameSpace" to prevent future confusion while
still avoiding the keyword.
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: https://postgr.es/m/aJJxpfsDfiQ1VbJ5%40nathan
These were introduced (commit efdc7d7475) at the same time as we were
moving to using the standard inttypes.h format macros (commit
a0ed19e0a9). It doesn't seem useful to keep a new already-deprecated
interface like this with only a few users, so remove the new symbols
again and have the callers use PRIx64.
(Also, INT64_HEX_FORMAT was kind of a misnomer, since hex formats all
use unsigned types.)
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/0ac47b5d-e5ab-4cac-98a7-bdee0e2831e4%40eisentraut.org
Following commit e035863c9a, building with -O0 began triggering
warnings about potentially uninitialized 'workbuf' usage. While
theoretically the initialization isn't necessary since VARDATA()
doesn't access the contents of the pointed-to object, this commit
explicitly initializes the workbuf variable to suppress the warning.
Buildfarm members adder and flaviventris have shown the warning.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAD21AoCOZxfqnNgfM5yVKJZYnOq5m2Q96fBGy1fovEqQ9V4OZA@mail.gmail.com
The result of "DirectFunctionCall1(numeric_float8, d)" is already in
Datum form, but the code was incorrectly applying PG_RETURN_FLOAT8()
to it. On machines where float8 is pass-by-reference, this would
result in complete garbage, since an unpredictable pointer value
would be treated as an integer and then converted to float. It's not
entirely clear how much of a problem would ensue on 64-bit hardware,
but certainly interpreting a float8 bitpattern as uint64 and then
converting that to float isn't the intended behavior.
As luck would have it, even the complete-garbage case doesn't break
BRIN indexes, since the results are only used to make choices about
how to merge values into ranges: at worst, we'd make poor choices
resulting in an inefficient index. Doubtless that explains the lack
of field complaints. However, users with BRIN indexes that use the
numeric_minmax_multi_ops opclass may wish to reindex in hopes of
making their indexes more efficient.
Author: Peter Eisentraut <peter@eisentraut.org>
Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/2093712.1753983215@sss.pgh.pa.us
Backpatch-through: 14
This commit introduces a new column backup_type that indicates the
type of backup being performed: either 'full' or 'incremental'.
Bump catalog version.
Author: Shinya Kato <shinya11.kato@gmail.com>
Reviewed-by: Yugo Nagata <nagata@sraoss.co.jp>
Discussion: https://postgr.es/m/CAOzEurQuzbHwTj1ehk1a+eeQDidJPyrE5s6mYumkjwjZnurhkQ@mail.gmail.com
During CREATE DATABASE, if changing the locale provider, require that
a new locale is specified rather than trying to reinterpret the
template's locale using the new provider.
This only affects the behavior when the template uses the builtin
provider and CREATE DATABASE specifies the ICU provider without
specifying the locale. Previously, that may have succeeded due to
loose validation by ICU, whereas now that will cause an error. Because
it can cause an error, backport only to unreleased versions.
Discussion: https://postgr.es/m/5038b33a6dc639009f4b3d43fa6ae0c5ba9e04f7.camel@j-davis.com
Backpatch-through: 18
Macros like VARDATA() and VARSIZE() should be thought of as taking
values of type pointer to struct varlena or some other related struct.
The way they are implemented, you can pass anything to it and it will
cast it right. But this is in principle incorrect. To fix, add the
required DatumGetPointer() calls. Or in a couple of cases, remove
superfluous PointerGetDatum() calls.
It is planned in a subsequent patch to change macros like VARDATA()
and VARSIZE() to inline functions, which will enforce stricter typing.
This is in preparation for that.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/928ea48f-77c6-417b-897c-621ef16685a6%40eisentraut.org
Previously, specifying the publication option 'publish_generated_columns'
without an explicit value would incorrectly default to 'stored', which is
not the intended behavior.
This patch fixes the issue by raising an ERROR when no value is provided
for 'publish_generated_columns', ensuring that users must explicitly
specify a valid option.
Author: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Backpatch-through: 18, where it was introduced
Discussion: https://postgr.es/m/CAHut+PsCUCWiEKmB10DxhoPfXbF6jw5RD9ib2LuaQeA_XraW7w@mail.gmail.com
Previously, enabling sync_replication_slots while wal_level was not set
to logical could cause the server to shut down. This was because
the postmaster performed a configuration check before launching
the slot synchronization worker and raised an ERROR if the settings
were incompatible. Since ERROR is treated as FATAL in the postmaster,
this resulted in the entire server shutting down unexpectedly.
This commit changes the postmaster to log that message with a LOG-level
instead of raising an ERROR, allowing the server to continue running
even with the misconfiguration.
Back-patch to v17, where slot synchronization was introduced.
Reported-by: Hugo DUBOIS <hdubois@scaleway.com>
Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Hugo DUBOIS <hdubois@scaleway.com>
Reviewed-by: Shveta Malik <shveta.malik@gmail.com>
Discussion: https://postgr.es/m/CAH0PTU_pc3oHi__XESF9ZigCyzai1Mo3LsOdFyQA4aUDkm01RA@mail.gmail.com
Backpatch-through: 17
This enhancement builds upon the infrastructure introduced in commit
228c370868, which enables the preservation of deleted tuples and their
origin information on the subscriber. This capability is crucial for
handling concurrent transactions replicated from remote nodes.
The update introduces support for detecting update_deleted conflicts
during the application of update operations on the subscriber. When an
update operation fails to locate the target row-typically because it has
been concurrently deleted-we perform an additional table scan. This scan
uses the SnapshotAny mechanism and we do this additional scan only when
the retain_dead_tuples option is enabled for the relevant subscription.
The goal of this scan is to locate the most recently deleted tuple-matching
the old column values from the remote update-that has not yet been removed
by VACUUM and is still visible according to our slot (i.e., its deletion
is not older than conflict-detection-slot's xmin). If such a tuple is
found, the system reports an update_deleted conflict, including the origin
and transaction details responsible for the deletion.
This provides a groundwork for more robust and accurate conflict
resolution process, preventing unexpected behavior by correctly
identifying cases where a remote update clashes with a deletion from
another origin.
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: shveta malik <shveta.malik@gmail.com>
Reviewed-by: Nisha Moond <nisha.moond412@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/OS0PR01MB5716BE80DAEB0EE2A6A5D1F5949D2@OS0PR01MB5716.jpnprd01.prod.outlook.com
Coverity complained that the "errtrace" string is leaked if we return
early because backtrace_symbols fails. Another criticism that could
be leveled at this is that not providing any hint of what happened is
user-unfriendly. Fix that.
The odds of a leak here are small, and typically it wouldn't matter
anyway since the leak will be in ErrorContext which will soon get
reset. So I'm not feeling a need to back-patch.
If ndatums is zero, the code would allocate zero-length boundKinds
and boundDatums chunks, which would have nothing pointing to them,
leading to Valgrind complaints. Rearrange the code to avoid the
useless pallocs, and also to not bother computing byval/typlen when
they aren't used.
I'm unsure why I didn't see this in my Valgrind testing back in May.
This code hasn't changed since then, but maybe we added a regression
test that reaches this edge case. Or possibly I just failed to
notice the reports, which do say "0 bytes lost".
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/285483.1746756246@sss.pgh.pa.us
CompleteCachedPlan intentionally doesn't worry about small
leaks from PlanCacheComputeResultDesc. However, Valgrind
knows nothing of engineering tradeoffs and complains anyway.
Silence it by doing things the hard way if USE_VALGRIND.
I don't really love this patch, because it makes the handling
of plansource->resultDesc different from the handling of query
dependencies and search_path just above, which likewise are willing
to accept small leaks into the cached plan's context. However,
those cases aren't provoking Valgrind complaints. (Perhaps in a
CLOBBER_CACHE_ALWAYS build, they would?) For the moment, this
makes the src/pl/plpgsql tests leak-free according to Valgrind.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/285483.1746756246@sss.pgh.pa.us
Like the situation with function cache loading, text search
dictionary loading functions tend to leak some cruft into the
dictionary's long-lived cache context. To judge by the examples in
the core regression tests, not very many bytes are at stake.
Moreover, I don't see a way to prevent such leaks without changing the
API for TS template initialization functions: right now they do not
have to worry about making sure that their results are long-lived.
Hence, I think we should install a suppression rule rather than trying
to fix this completely. However, I did grab some low-hanging fruit:
several places were leaking the result of get_tsearch_config_filename.
This seems worth doing mostly because they are inconsistent with other
dictionaries that were freeing it already.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/285483.1746756246@sss.pgh.pa.us
These changes don't actually fix any leaks. They just make sure that
Valgrind will find pointers to data structures that remain allocated
at process exit, and thus not falsely complain about leaks. In
particular, we are trying to avoid situations where there is no
pointer to the beginning of an allocated block (except possibly
within the block itself, which Valgrind won't count).
* Because dynahash.c never frees hashtable storage except by deleting
the whole hashtable context, it doesn't bother to track the individual
blocks of elements allocated by element_alloc(). This results in
"possibly lost" complaints from Valgrind except when the first element
of each block is actively in use. (Otherwise it'll be on a freelist,
but very likely only reachable via "interior pointers" within element
blocks, which doesn't satisfy Valgrind.)
To fix, if we're building with USE_VALGRIND, expend an extra pointer's
worth of space in each element block so that we can chain them all
together from the HTAB header. Skip this in shared hashtables though:
Valgrind doesn't track those, and we'd need additional locking to make
it safe to manipulate a shared chain.
While here, update a comment obsoleted by 9c911ec06.
* Put the dlist_node fields of catctup and catclist structs first.
This ensures that the dlist pointers point to the starts of these
palloc blocks, and thus that Valgrind won't consider them
"possibly lost".
* The postmaster's PMChild structs and the autovac launcher's
avl_dbase structs also have the dlist_node-is-not-first problem,
but putting it first still wouldn't silence the warning because we
bulk-allocate those structs in an array, so that Valgrind sees a
single allocation. Commonly the first array element will be pointed
to only from some later element, so that the reference would be an
interior pointer even if it pointed to the array start. (This is the
same issue as for dynahash elements.) Since these are pretty simple
data structures, I don't feel too bad about faking out Valgrind by
just keeping a static pointer to the array start.
(This is all quite hacky, and it's not hard to imagine usages where
we'd need some other idea in order to have reasonable leak tracking of
structures that are only accessible via dlist_node lists. But these
changes seem to be enough to silence this class of leakage complaints
for the moment.)
* Free a couple of data structures manually near the end of an
autovacuum worker's run when USE_VALGRIND, and ensure that the final
vac_update_datfrozenxid() call is done in a non-permanent context.
This doesn't have any real effect on the process's total memory
consumption, since we're going to exit as soon as that last
transaction is done. But it does pacify Valgrind.
* Valgrind complains about the postmaster's socket-files and
lock-files lists being leaked, which we can silence by just
not nulling out the static pointers to them.
* Valgrind seems not to consider the global "environ" variable as
a valid root pointer; so when we allocate a new environment array,
it claims that data is leaked. To fix that, keep our own
statically-allocated copy of the pointer, similarly to the previous
item.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/285483.1746756246@sss.pgh.pa.us
In the current system architecture, none of these are worth obsessing
over; most are once-per-process leaks. However, Valgrind complains
about all of them, and if we get to using threads rather than
processes for backend sessions, it will become more interesting to
avoid per-session leaks.
* Fix leaks in StartupXLOG() and ShutdownWalRecovery().
* Fix leakage of pq_mq_handle in a parallel worker.
While at it, move mq_putmessage's "Assert(pq_mq_handle != NULL)"
to someplace where it's not trivially useless.
* Fix leak in logicalrep_worker_detach().
* Don't leak the startup-packet buffer in ProcessStartupPacket().
* Fix leak in evtcache.c's DecodeTextArrayToBitmapset().
If the presented array is toasted, this neglected to free the
detoasted copy, which was then leaked into EventTriggerCacheContext.
* I'm distressed by the amount of code that BuildEventTriggerCache
is willing to run while switched into a long-lived cache context.
Although the detoasted array is the only leak that Valgrind reports,
let's tighten things up while we're here. (DecodeTextArrayToBitmapset
is still run in the cache context, so doing this doesn't remove the
need for the detoast fix. But it reduces the surface area for other
leaks.)
* load_domaintype_info() intentionally leaked some intermediate cruft
into the long-lived DomainConstraintCache's memory context, reasoning
that the amount of leakage will typically not be much so it's not
worth doing a copyObject() of the final tree to avoid that. But
Valgrind knows nothing of engineering tradeoffs and complains anyway.
On the whole, the copyObject doesn't cost that much and this is surely
not a performance-critical code path, so let's do it the clean way.
* MarkGUCPrefixReserved didn't bother to clean up removed placeholder
GUCs at all, which shows up as a leak in one regression test.
It seems appropriate for it to do as much cleanup as
define_custom_variable does when replacing placeholders, so factor
that code out into a helper function. define_custom_variable's logic
was one brick shy of a load too: it forgot to free the separate
allocation for the placeholder's name.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/285483.1746756246@sss.pgh.pa.us
Arrange that only the "aligned chunk" part of the allocated space is
included in a Valgrind vchunk. This suppresses complaints about that
vchunk being possibly lost because PG is retaining only pointers to
the aligned chunk. Also make sure that trailing wasted space is
marked NOACCESS.
As a tiny performance improvement, arrange that MCXT_ALLOC_ZERO zeroes
only the returned "aligned chunk", not the wasted padding space.
In passing, fix GetLocalBufferStorage to use MemoryContextAllocAligned
instead of rolling its own implementation, which was equally broken
according to Valgrind.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/285483.1746756246@sss.pgh.pa.us
When determining whether an allocated chunk is still reachable,
Valgrind will consider only pointers within what it believes to be
allocated chunks. Normally, all of a block obtained from malloc()
would be considered "allocated" --- but it turns out that if we use
VALGRIND_MEMPOOL_ALLOC to designate sub-section(s) of a malloc'ed
block as allocated, all the rest of that malloc'ed block is ignored.
This leads to lots of false positives of course. In particular,
in any multi-malloc-block context, all but the primary block were
reported as leaked. We also had a problem with context "ident"
strings, which were reported as leaked unless there was some other
pointer to them besides the one in the context header.
To fix, we need to use VALGRIND_MEMPOOL_ALLOC to designate
a context's management structs (the context struct itself and
any per-block headers) as allocated chunks. That forces moving
the VALGRIND_CREATE_MEMPOOL/VALGRIND_DESTROY_MEMPOOL calls into
the per-context-type code, so that the pool identifier can be
made as soon as we've allocated the initial block, but otherwise
it's fairly straightforward. Note that in Valgrind's eyes there
is no distinction between these allocations and the allocations
that the mmgr modules hand out to user code. That's fine for
now, but perhaps someday we'll want to do better yet.
When reading this patch, it's helpful to start with the comments
added at the head of mcxt.c.
Author: Andres Freund <andres@anarazel.de>
Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/285483.1746756246@sss.pgh.pa.us
Discussion: https://postgr.es/m/20210317181531.7oggpqevzz6bka3g@alap3.anarazel.de
In ReorderBufferProcessTXN(), used to send the data of a transaction to
an output plugin, INSERT ON CONFLICT changes (INTERNAL_SPEC_INSERT) are
delayed until a confirmation record arrives (INTERNAL_SPEC_CONFIRM),
updating the change being processed.
8c58624df4 has added an extra step after processing a change to update
the progress of the transaction, by calling the callback
update_progress_txn() based on the LSN stored in a change after a
threshold of CHANGES_THRESHOLD (100) is reached. This logic has missed
the fact that for an INSERT ON CONFLICT change the data is freed once
processed, hence update_progress_txn() could be called pointing to a LSN
value that's already been freed. This could result in random crashes,
depending on the workload.
Per discussion, this issue is fixed by reusing in update_progress_txn()
the LSN from the change processed found at the beginning of the loop,
meaning that for a INTERNAL_SPEC_CONFIRM change the progress is updated
using the LSN of the INTERNAL_SPEC_CONFIRM change, and not the LSN from
its INTERNAL_SPEC_INSERT change. This is actually more correct, as we
want to update the progress to point to the INTERNAL_SPEC_CONFIRM
change.
Masahiko Sawada has found a nice trick to reproduce the issue: hardcode
CHANGES_THRESHOLD at 1 and run test_decoding (test "ddl" being enough)
on an instance running valgrind. The bug has been analyzed by Ethan
Mertz, who also originally suggested the solution used in this patch.
Issue introduced by 8c58624df4, so backpatch down to v16.
Author: Ethan Mertz <ethan.mertz@gmail.com>
Co-authored-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/aIsQqDZ7x4LAQ6u1@paquier.xyz
Backpatch-through: 16
Currently, ALTER DATABASE/ROLE/SYSTEM RESET [ALL] with an unknown
custom GUC with a prefix reserved by MarkGUCPrefixReserved() errors
(unless a superuser runs a RESET ALL variant). This is problematic
for cases such as an extension library upgrade that removes a GUC.
To fix, simply make sure the relevant code paths explicitly allow
it. Note that we require superuser or privileges on the parameter
to reset it. This is perhaps a bit more restrictive than is
necessary, but it's not clear whether further relaxing the
requirements is safe.
Oversight in commit 88103567cb. The ALTER SYSTEM fix is dependent
on commit 2d870b4aef, which first appeared in v17. Unfortunately,
back-patching that commit would introduce ABI breakage, and while
that breakage seems unlikely to bother anyone, it doesn't seem
worth the risk. Hence, the ALTER SYSTEM part of this commit is
omitted on v15 and v16.
Reported-by: Mert Alev <mert@futo.org>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Discussion: https://postgr.es/m/18964-ba09dea8c98fccd6%40postgresql.org
Backpatch-through: 15
A deadlock can occur when the DDL command and the apply worker acquire
catalog locks in different orders while dropping replication origins.
The issue is rare in PG16 and higher branches because, in most cases, the
tablesync worker performs the origin drop in those branches, and its
locking sequence does not conflict with DDL operations.
This patch ensures consistent lock acquisition to prevent such deadlocks.
As per buildfarm.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Ajin Cherian <itsajin@gmail.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 14, where it was introduced
Discussion: https://postgr.es/m/bab95e12-6cc5-4ebb-80a8-3e41956aa297@gmail.com
Commit 719dcf3c42 introduced a field called CachedPlanType in
PlannedStmt to allow extensions to determine whether a cached plan is
generic or custom.
After discussion, the concepts that we want to track are a bit wider
than initially anticipated, as it is closer to knowing from which
"source" or "origin" a PlannedStmt has been generated or retrieved.
Custom and generic cached plans are a subset of that.
Based on the state of HEAD, we have been able to define two more
origins:
- "standard", for the case where PlannedStmt is generated in
standard_planner(), the most common case.
- "internal", for the fake PlannedStmt generated internally by some
query patterns.
This could be tuned in the future depending on what is needed. This
looks like a good starting point, at least. The default value is called
"UNKNOWN", provided as fallback value. This value is not used in the
core code, the idea is to let extensions building their own PlannedStmts
know about this new field.
Author: Michael Paquier <michael@paquier.xyz>
Co-authored-by: Sami Imseih <samimseih@gmail.com>
Discussion: https://postgr.es/m/aILaHupXbIGgF2wJ@paquier.xyz
If the client sent a query cancel request with backend PID 0, it
tripped an assertion. With assertions disabled, you got this in the
log instead:
LOG: invalid cancel request with PID 0
LOG: wrong key in cancel request for process 0
Query cancellations don't even require authentication, so we better
tolerate bogus requests. Fix by turning the assertion into a regular
runtime check.
Spotted while testing libpq behavior with a modified server that
didn't send BackendKeyData to the client.
Backpatch-through: 18
For many optional libraries, we extract the -L and -l switches needed
to link the library from a helper program such as llvm-config. In
some cases we put the resulting -L switches into LDFLAGS ahead of
-L switches specified via --with-libraries. That risks breaking
the user's intention for --with-libraries.
It's not such a problem if the library's -L switch points to a
directory containing only that library, but on some platforms a
library helper may "helpfully" offer a switch such as -L/usr/lib
that points to a directory holding all standard libraries. If the
user specified --with-libraries in hopes of overriding the standard
build of some library, the -L/usr/lib switch prevents that from
happening since it will come before the user-specified directory.
To fix, avoid inserting these switches directly into LDFLAGS during
configure, instead adding them to LIBDIRS or SHLIB_LINK. They will
still eventually get added to LDFLAGS, but only after the switches
coming from --with-libraries.
The same problem exists for -I switches: those coming from
--with-includes should appear before any coming from helper programs
such as llvm-config. We have not heard field complaints about this
case, but it seems certain that a user attempting to override a
standard library could have issues.
The changes for this go well beyond configure itself, however,
because many Makefiles have occasion to manipulate CPPFLAGS to
insert locally-desirable -I switches, and some of them got it wrong.
The correct ordering is any -I switches pointing at within-the-
source-tree-or-build-tree directories, then those from the tree-wide
CPPFLAGS, then those from helper programs. There were several places
that risked pulling in a system-supplied copy of libpq headers, for
example, instead of the in-tree files. (Commit cb36f8ec2 fixed one
instance of that a few months ago, but this exercise found more.)
The Meson build scripts may or may not have any comparable problems,
but I'll leave it to someone else to investigate that.
Reported-by: Charles Samborski <demurgos@demurgos.net>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/70f2155f-27ca-4534-b33d-7750e20633d7@demurgos.net
Backpatch-through: 13
When I prepared 71c0921b6 et al yesterday, I was thinking that the
logic involving explicitly freeing the node_list output was still
needed to dodge leakage bugs in libxml2. But I was misremembering:
we introduced that only because with early 2.13.x releases we could
not trust xmlParseBalancedChunkMemory's result code, so we had to
look to see if a node list was returned or not. There's no reason
to believe that xmlParseBalancedChunkMemory will fail to clean up
the node list when required, so simplify. (This essentially
completes reverting all the non-cosmetic changes in 6082b3d5d.)
Reported-by: Jim Jones <jim.jones@uni-muenster.de>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/997668.1753802857@sss.pgh.pa.us
Backpatch-through: 13
There've been a few complaints that it can be overly difficult to figure
out why the planner picked a Memoize plan. To help address that, here we
adjust the EXPLAIN output to display the following additional details:
1) The estimated number of cache entries that can be stored at once
2) The estimated number of unique lookup keys that we expect to see
3) The number of lookups we expect
4) The estimated hit ratio
Technically #4 can be calculated using #1, #2 and #3, but it's not a
particularly obvious calculation, so we opt to display it explicitly.
The original patch by Lukas Fittl only displayed the hit ratio, but
there was a fear that might lead to more questions about how that was
calculated. The idea with displaying all 4 is to be transparent which
may allow queries to be tuned more easily. For example, if #2 isn't
correct then maybe extended statistics or a manual n_distinct estimate can
be used to help fix poor plan choices.
Author: Ilia Evdokimov <ilya.evdokimov@tantorlabs.com>
Author: Lukas Fittl <lukas@fittl.com>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/CAP53Pky29GWAVVk3oBgKBDqhND0BRBN6yTPeguV_qSivFL5N_g%40mail.gmail.com
This mostly reverts commit 6082b3d5d, "Use xmlParseInNodeContext
not xmlParseBalancedChunkMemory". It turns out that
xmlParseInNodeContext will reject text chunks exceeding 10MB, while
(in most libxml2 versions) xmlParseBalancedChunkMemory will not.
The bleeding-edge libxml2 bug that we needed to work around a year
ago is presumably no longer a factor, and the argument that
xmlParseBalancedChunkMemory is semi-deprecated is not enough to
justify a functionality regression. Hence, go back to doing it
the old way.
Reported-by: Michael Paquier <michael@paquier.xyz>
Author: Michael Paquier <michael@paquier.xyz>
Co-authored-by: Erik Wienhold <ewie@ewie.name>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/aIGknLuc8b8ega2X@paquier.xyz
Backpatch-through: 13
Commit ffae5cc5a6 added this hint in 2006,
but it's now obsolete and doesn't reflect what users should really check
in this situation. We were not able to agree on a new hint, so just delete
the existing one and update the comments to mention one possibility that
is known to cause problems of this kind: something other than PostgreSQL
is modifying files in the PostgreSQL data directory.
Author: Jakub Wartak <jakub.wartak@enterprisedb.com>
Reviewed-by: Robert Haas <rhaas@postgresql.org>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Christoph Berg <myon@debian.org>
Discussion: https://postgr.es/m/CAKZiRmxNbcaL76x=09Sxf7aUmrRQJBf8drzDdUHo+j9_eM+VMg@mail.gmail.com
Commit 473a575e05 purported to make this
function stash the error message in *syncrep_parse_result_p, but
it didn't actually.
As a result, an attempt to set synchronous_standby_names to any value
that does not parse resulted in a generic "parser failed." message
rather than anything more specific. This fixes that.
Discussion: http://postgr.es/m/CA+TgmoYF9wPNZ-Q_EMfib_espgHycY-eX__6Tzo2GpYpVXqCdQ@mail.gmail.com
Backpatch-through: 18
The callback added in fc415edf8c used to check if there is any pending
data to flush for fixed-numbered statistics, done by looping across all
the builtin and custom stats kinds with a call to have_fixed_pending_cb,
is proving to able to show in workloads that do not report any stats
(read-only, no function calls, no WAL, no IO, etc). The code used in
v17 was cheaper than that what HEAD has introduced, relying on three
boolean checks for WAL, SLRU and IO stats.
This commit switches the code to use a more efficient approach than
fc415edf8c, with a single boolean flag that can be switched to "true"
by any fixed-numbered stats kinds to force pgstat_report_stat() to go
through one round of reports. The flag is reset by pgstat_report_stat()
once a full round of reports is done. The flag being false means that
fixed-numbered stats kinds saw no activity, and that there is no pending
data to flush.
ac000fca74 took one step in improving the performance by reducing the
number of stats kinds that the backend can hold. This commit takes a
more drastic step by bringing back the code efficiency to what it was
before v18 with a cheap check at the beginning of pgstat_report_stat()
for its fast-exit path.
The callback have_static_pending_cb is removed as an effect of all that.
Reported-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/eb224uegsga2hgq7dfq3ps5cduhpqej7ir2hjxzzozjthrekx5@dysei6buqthe
Backpatch-through: 18
If the number of sync requests is big enough, the palloc() call in
AbsorbSyncRequests() will attempt to allocate more than 1 GB of memory,
resulting in failure. This can lead to an infinite loop in the checkpointer
process, as it repeatedly fails to absorb the pending requests.
This commit introduces the following changes to cope with this problem:
1. Turn pending checkpointer requests array in shared memory into a bounded
ring buffer.
2. Limit maximum ring buffer size to 10M items.
3. Make AbsorbSyncRequests() process requests incrementally in 10K batches.
Even #2 makes the whole queue size fit the maximum palloc() size of 1 GB.
of continuous lock holding.
This commit is for master only. Simpler fix, which just limits a request
queue size to 10M, will be backpatched.
Reported-by: Ekaterina Sokolova <e.sokolova@postgrespro.ru>
Discussion: https://postgr.es/m/db4534f83a22a29ab5ee2566ad86ca92%40postgrespro.ru
Author: Maxim Orlov <orlovmg@gmail.com>
Co-authored-by: Xuneng Zhou <xunengzhou@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
Similar checks are done for the mandatory table AM callbacks. A portion
of the index AM callbacks are optional and can be NULL; the rest is
mandatory and is documented as such in the documentation and in amapi.h.
These checks are useful to detect quickly if all the mandatory callbacks
are defined when implementing a new index access method, as the
assertions are run when loading the AM.
Author: Japin Li <japinli@hotmail.com>
Discussion: https://postgr.es/m/ME0P300MB0445795D31CEAB92C58B41FDB651A@ME0P300MB0445.AUSP300.PROD.OUTLOOK.COM
Remove a bunch of PG_TRY constructs, de-volatilize related
variables, remove some PQclear calls in error paths.
Aside from making the code simpler and shorter, this should
provide some marginal performance gains.
For ease of review, I did not re-indent code within the removed
PG_TRY constructs. That'll be done in a separate patch.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Matheus Alcantara <matheusssilv97@gmail.com>
Discussion: https://postgr.es/m/2976982.1748049023@sss.pgh.pa.us
Commit 232d8caea fixed a case where postgres_fdw could lose track
of a PGresult object, resulting in a process-lifespan memory leak.
But I have little faith that there aren't other potential PGresult
leakages, now or in future, in the backend modules that use libpq.
Therefore, this patch proposes infrastructure that makes all
PGresults returned from libpq act as though they are palloc'd
in the CurrentMemoryContext (with the option to relocate them to
another context later). This should greatly reduce the risk of
careless leaks, and it also permits removal of a bunch of code
that attempted to prevent such leaks via PG_TRY blocks.
This patch adds infrastructure that wraps each PGresult in a
"libpqsrv_PGresult" that provides a memory context reset callback
to PQclear the PGresult. Code using this abstraction is inherently
memory-safe to the same extent as we are accustomed to in most backend
code. Furthermore, we add some macros that automatically redirect
calls of the libpq functions concerned with PGresults to use this
infrastructure, so that almost no source-code changes are needed to
wheel this infrastructure into place in all the backend code that
uses libpq.
Perhaps in future we could create similar infrastructure for
PGconn objects, but there seems less need for that.
This patch just creates the infrastructure and makes relevant code
use it, including reverting 232d8caea in favor of this mechanism.
A good deal of follow-on simplification is possible now that we don't
have to be so cautious about freeing PGresults, but I'll put that in
a separate patch.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Matheus Alcantara <matheusssilv97@gmail.com>
Discussion: https://postgr.es/m/2976982.1748049023@sss.pgh.pa.us
This flag was effectively a no-op in EXEC_BACKEND (ie, Windows)
builds, because it was kept in the process-local HTAB struct,
and it could only ever become set in the postmaster's copy.
The simplest fix is to move it to the shared HASHHDR struct.
We could keep a copy in HTAB as well, as we do with keysize
and some other fields, but the "too much contention" argument
doesn't seem to apply here: we only examine isfixed during
element_alloc(), which had better not get hit very often for
a shared hashtable.
This oversight dates to 7c797e719 which invented the option.
But back-patching doesn't seem appropriate given the lack of
field complaints. If there is anyone running an affected
workload on Windows, they might be unhappy about the behavior
changing in a minor release.
Author: Aidar Imamov <a.imamov@postgrespro.ru>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/4d0cb35ff01c5c74d2b9a582ecb73823@postgrespro.ru
This changes the grammar for REINDEX, CHECKPOINT, CLUSTER, ANALYZE/ANALYSE;
they still accept the same options as before, but the grammar is written
differently for convenience of future development.
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/202507231538.ir7pjzoow6oe@alvherre.pgsql
Previously, if a background worker crashed (e.g., due to a SIGKILL) and
the server restarted due to restart_after_crash being enabled,
the worker was not restarted as expected. Background workers without
the never-restart flag should automatically restart in this case.
This issue was introduced in commit 28a520c0b7, which failed to reset
the rw_pid field in the RegisteredBgWorker struct for the crashed worker.
This commit fixes the problem by resetting rw_pid for all eligible
background workers during the crash-and-restart cycle.
Back-patched to v18, where the bug was introduced.
Bug fix patches were proposed by Andrey Rudometov and ChangAo Chen,
but this commit uses a different approach.
Reported-by: Andrey Rudometov <unlimitedhikari@gmail.com>
Reported-by: ChangAo Chen <cca5507@qq.com>
Author: Andrey Rudometov <unlimitedhikari@gmail.com>
Author: ChangAo Chen <cca5507@qq.com>
Co-authored-by: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: ChangAo Chen <cca5507@qq.com>
Reviewed-by: Shveta Malik <shveta.malik@gmail.com>
Discussion: https://postgr.es/m/CAF6JsWiO=i24qYitWe6ns1sXqcL86rYxdyU+pNYk-WueKPSySg@mail.gmail.com
Discussion: https://postgr.es/m/tencent_E00A056B3953EE6440F0F40F80EC30427D09@qq.com
Backpatch-through: 18
LatchWaitSetPostmasterDeathPos, the latch event position for the
postmaster death event, is initialized under IsUnderPostmaster.
WaitLatch() considered it as a valid wait target in single-user mode
(!IsUnderPostmaster), which was incorrect.
One code path found to fail with an assertion failure is a database drop
in single-user mode while waiting in WaitForProcSignalBarrier() after
the drop.
Oversight in commit 84e5b2f07a.
Author: Patrick Stählin <me@packi.ch>
Co-authored-by: Ronan Dunklau <ronan.dunklau@aiven.io>
Discussion: https://postgr.es/m/18996-3a2744c8140488de@postgresql.org
Backpatch-through: 18
This function is declared as returning a uint8, but it returns a
bool in one code path. To fix, return (uint8) 0 instead of false
there. This should behave exactly the same as before, but it might
prevent future compiler complaints.
Oversight in commit a892234f83.
Author: Julien Rouhaud <rjuju123@gmail.com>
Discussion: https://postgr.es/m/aIHluT2isN58jqHV%40jrouhaud
PlannedStmt gains a new field, called CachedPlanType, able to track if a
given plan tree originates from the cache and if we are dealing with a
generic or custom cached plan.
This field can be used for monitoring or statistical purposes, in the
executor hooks, for example, based on the planned statement attached to
a QueryDesc. A patch is under discussion for pg_stat_statements to
provide an equivalent of the counters in pg_prepared_statements for
custom and generic plans, to provide a more global view of such data, as
this data is now restricted to the current session.
The concept introduced in this commit is useful on its own, and has been
extracted from a larger patch by the same author.
Author: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAA5RZ0uFw8Y9GCFvafhC=OA8NnMqVZyzXPfv_EePOt+iv1T-qQ@mail.gmail.com
Solaris has never bothered to add "const" to the second argument
of PAM conversation procs, as all other Unixen did decades ago.
This resulted in an "incompatible pointer" compiler warning when
building --with-pam, but had no more serious effect than that,
so we never did anything about it. However, as of GCC 14 the
case is an error not warning by default.
To complicate matters, recent OpenIndiana (and maybe illumos
in general?) *does* supply the "const" by default, so we can't
just assume that platforms using our solaris template need help.
What we can do, short of building a configure-time probe,
is to make solaris.h #define _PAM_LEGACY_NONCONST, which
causes OpenIndiana's pam_appl.h to revert to the traditional
definition, and hopefully will have no effect anywhere else.
Then we can use that same symbol to control whether we include
"const" in the declaration of pam_passwd_conv_proc().
Bug: #18995
Reported-by: Andrew Watkins <awatkins1966@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18995-82058da9ab4337a7@postgresql.org
Backpatch-through: 13
lwlock.c, lwlock.h, and wait_event_names.txt each contain a list of
built-in LWLock tranches. It is easy to miss one or the other when
adding or removing tranches, and discrepancies have adverse effects
(e.g., breaking JOINs between pg_stat_activity and pg_wait_events).
This commit moves the lists of built-in tranches in lwlock.{c,h} to
lwlocklist.h and adds a cross-check to the script that generates
lwlocknames.h. If the lists do not match exactly, building will
fail.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/aHpOgwuFQfcFMZ/B%40ip-10-97-1-34.eu-west-3.compute.internal
Logical replication requires reliable conflict detection to maintain data
consistency across nodes. To achieve this, we must prevent premature
removal of tuples deleted by other origins and their associated commit_ts
data by VACUUM, which could otherwise lead to incorrect conflict reporting
and resolution.
This patch introduces a mechanism to retain deleted tuples on the
subscriber during the application of concurrent transactions from remote
nodes. Retaining these tuples allows us to correctly ignore concurrent
updates to the same tuple. Without this, an UPDATE might be misinterpreted
as an INSERT during resolutions due to the absence of the original tuple.
Additionally, we ensure that origin metadata is not prematurely removed by
vacuum freeze, which is essential for detecting update_origin_differs and
delete_origin_differs conflicts.
To support this, a new replication slot named pg_conflict_detection is
created and maintained by the launcher on the subscriber. Each apply
worker tracks its own non-removable transaction ID, which the launcher
aggregates to determine the appropriate xmin for the slot, thereby
retaining necessary tuples.
Conflict information retention (deleted tuples and commit_ts) can be
enabled per subscription via the retain_conflict_info option. This is
disabled by default to avoid unnecessary overhead for configurations that
do not require conflict resolution or logging.
During upgrades, if any subscription on the old cluster has
retain_conflict_info enabled, a conflict detection slot will be created to
protect relevant tuples from deletion when the new cluster starts.
This is a foundational work to correctly detect update_deleted conflict
which will be done in a follow-up patch.
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: shveta malik <shveta.malik@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: Nisha Moond <nisha.moond412@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/OS0PR01MB5716BE80DAEB0EE2A6A5D1F5949D2@OS0PR01MB5716.jpnprd01.prod.outlook.com
Commit 112faf1378 introduced a translation marker in libpq-be-fe-helpers.h,
but this caused build failures on some platforms—such as the one reported
by buildfarm member indri—due to linker issues with dblink. This is the same
problem previously addressed in commit 213c959a29.
To fix the issue, this commit removes the translation marker from
libpq-be-fe-helpers.h, following the approach used in 213c959a29.
It also removes the associated gettext_noop() calls added in commit
112faf1378, as they are no longer needed.
While reviewing this, a gettext_noop() call was also found in
contrib/basic_archive. Since contrib modules don't support translation,
this call has been removed as well.
Per buildfarm member indri.
Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Discussion: https://postgr.es/m/0e6299d9-608a-4ffa-aeb1-40cb8a99000b@oss.nttdata.com
Previously, NOTICE, WARNING, and similar messages received from remote
servers over replication, postgres_fdw, or dblink connections were printed
directly to stderr on the local server (e.g., the subscriber). As a result,
these messages lacked log prefixes (e.g., timestamp), making them harder
to trace and correlate with other log entries.
This commit addresses the issue by introducing a custom notice receiver
for replication, postgres_fdw, and dblink connections. These messages
are now logged via ereport(), ensuring they appear in the logs with proper
formatting and context, which improves clarity and aids in debugging.
Author: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/CALDaNm2xsHpWRtLm-VL_HJCsaE3+1Y_n-jDEAr3-suxVqc3xoQ@mail.gmail.com
In commit b262ad440, we introduced an optimization that reduces an IS
[NOT] NULL qual on a NOT NULL column to constant true or constant
false, provided we can prove that the input expression of the NullTest
is not nullable by any outer joins or grouping sets. This deduction
happens quite late in the planner, during the distribution of quals to
rels in query_planner. However, this approach has some drawbacks: we
can't perform any further folding with the constant, and it turns out
to be prone to bugs.
Ideally, this deduction should happen during constant folding.
However, the per-relation information about which columns are defined
as NOT NULL is not available at that point. This information is
currently collected from catalogs when building RelOptInfos for base
or "other" relations.
This patch moves the collection of NOT NULL attribute information for
relations before pull_up_sublinks, storing it in a hash table keyed by
relation OID. It then uses this information to perform the NullTest
deduction for Vars during constant folding. This also makes it
possible to leverage this information to pull up NOT IN subqueries.
Note that this patch does not get rid of restriction_is_always_true
and restriction_is_always_false. Removing them would prevent us from
reducing some IS [NOT] NULL quals that we were previously able to
reduce, because (a) the self-join elimination may introduce new IS NOT
NULL quals after constant folding, and (b) if some outer joins are
converted to inner joins, previously irreducible NullTest quals may
become reducible.
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAMbWs4-bFJ1At4btk5wqbezdu8PLtQ3zv-aiaY3ry9Ymm=jgFQ@mail.gmail.com
There are several pieces of catalog information that need to be
retrieved for a relation during the early stage of planning. These
include relhassubclass, which is used to clear the inh flag if the
relation has no children, as well as a column's attgenerated and
default value, which are needed to expand virtual generated columns.
More such information may be required in the future.
Currently, these pieces of catalog data are collected in multiple
places, resulting in repeated table_open/table_close calls for each
relation in the rangetable. This patch centralizes the collection of
all required early-stage catalog information into a single loop over
the rangetable, allowing each relation to be opened and closed only
once.
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAMbWs4-bFJ1At4btk5wqbezdu8PLtQ3zv-aiaY3ry9Ymm=jgFQ@mail.gmail.com
Currently, we expand virtual generated columns after we have pulled up
any SubLinks within the query's quals. This ensures that the virtual
generated column references within SubLinks that should be transformed
into joins are correctly expanded. This approach works well and has
posed no issues.
In an upcoming patch, we plan to centralize the collection of catalog
information needed early in the planner. This will help avoid
repeated table_open/table_close calls for relations in the rangetable.
Since this information is required during sublink pull-up, we are
moving the expansion of virtual generated columns to occur beforehand.
To achieve this, if any EXISTS SubLinks can be pulled up, their
rangetables are processed just before pulling them up.
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAMbWs4-bFJ1At4btk5wqbezdu8PLtQ3zv-aiaY3ry9Ymm=jgFQ@mail.gmail.com
The only practical effect of these changes is to avoid a useless
list_copy() operation when there is a single hashclause. That's
never going to make any noticeable performance difference, but
the code is arguably clearer this way, especially if we take the
opportunity to add some comments so that readers don't have to
reverse-engineer the usage of these local variables. Also add
some braces for better/more consistent style.
Author: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAHewXNnHBOO9NEa=NBDYOrwZL4oHu2NOcTYvqyNyWEswo8f5OQ@mail.gmail.com
If a crash occurs while writing a WAL record that spans multiple pages, the
recovery process marks the page with the XLP_FIRST_IS_OVERWRITE_CONTRECORD
flag. However, logical decoding currently attempts to read the full WAL
record based on its expected size before checking this flag, which can lead
to an infinite wait if the remaining data is never written (e.g., no activity
after crash).
This patch updates the logic first to read the page header and check for
the XLP_FIRST_IS_OVERWRITE_CONTRECORD flag before attempting to reconstruct
the full WAL record. If the flag is set, decoding correctly identifies
the record as incomplete and avoids waiting for WAL data that will never
arrive.
Discussion: https://postgr.es/m/CAAKRu_ZCOzQpEumLFgG_%2Biw3FTa%2BhJ4SRpxzaQBYxxM_ZAzWcA%40mail.gmail.com
Discussion: https://postgr.es/m/CALDaNm34m36PDHzsU_GdcNXU0gLTfFY5rzh9GSQv%3Dw6B%2BQVNRQ%40mail.gmail.com
Author: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
Backpatch-through: 13
Instead of laboriously computing the exact output length, use strlen
to get an upper bound cheaply. (This is still O(N) of course, but
the constant factor is a lot less.) This will typically result in
overallocating the output datum, but that's of little concern since
it's a short-lived allocation in just about all use-cases.
A simple microbenchmark showed about 40% speedup for long input
strings.
While here, make some cosmetic cleanups and add a test case that
covers the double-backslash code path in byteain and byteaout.
Author: Steven Niu <niushiji@gmail.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Reviewed-by: Stepan Neretin <slpmcf@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/ca315729-140b-426e-81a6-6cd5cfe7ecc5@gmail.com
If a MERGE inside a CTE attempts an UPDATE or DELETE on a table with
BEFORE ROW triggers, and a concurrent UPDATE or DELETE happens, the
merge code would fail (crashing in the case of an UPDATE action, and
potentially executing the wrong action for a DELETE action).
This is the same issue that 9321c79c86 attempted to fix, except now
for a MERGE inside a CTE. As noted in 9321c79c86, what needs to happen
is for the trigger code to exit early, returning the TM_Result and
TM_FailureData information to the merge code, if a concurrent
modification is detected, rather than attempting to do an EPQ
recheck. The merge code will then do its own rechecking, and rescan
the action list, potentially executing a different action in light of
the concurrent update. In particular, the trigger code must never call
ExecGetUpdateNewTuple() for MERGE, since that is bound to fail because
MERGE has its own per-action projection information.
Commit 9321c79c86 did this using estate->es_plannedstmt->commandType
in the trigger code to detect that a MERGE was being executed, which
is fine for a plain MERGE command, but does not work for a MERGE
inside a CTE. Fix by passing that information to the trigger code as
an additional parameter passed to ExecBRUpdateTriggers() and
ExecBRDeleteTriggers().
Back-patch as far as v17 only, since MERGE cannot appear inside a CTE
prior to that. Additionally, take care to preserve the trigger ABI in
v17 (though not in v18, which is still in beta).
Bug: #18986
Reported-by: Yaroslav Syrytsia <me@ys.lc>
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/18986-e7a8aac3d339fa47@postgresql.org
Backpatch-through: 17
We have an assertion to ensure that a command tag has been assigned by
the time we're done executing, but if we happen to execute a command
with no queries, the assertion would fail. Per discussion, rather than
contort things to get a tag assigned, just remove the assertion.
Oversight in 2f9661311b. That commit also retained a comment that
explained logic that had been adjacent to it but diffused into various
places, leaving none apt to keep part of the comment. Remove that part,
and rewrite what remains for extra clarity.
Bug: #18984
Backpatch-through: 13
Reported-by: Aleksander Alekseev <aleksander@tigerdata.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Michaël Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/18984-0f4778a6599ac3ae@postgresql.org
The terms used in wait_event_names.txt and lwlock.c were inconsistent
for MultiXactOffsetSLRU and MultiXactMemberSLRU, which could cause joins
between pg_wait_events and pg_stat_activity to fail. lwlock.c is
adjusted in this commit to what the historical name of the event has
always been, and what is documented.
Oversight in 53c2a97a92. 08b9b9e043 has fixed a similar
inconsistency some time ago.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Discussion: https://postgr.es/m/aHdxN0D0hKXzHFQG@ip-10-97-1-34.eu-west-3.compute.internal
Backpatch-through: 17
Avoid dependence on setlocale().
strcoll(), etc., are not called directly; all collation-sensitive
calls should go through pg_locale.c and use the appropriate
provider. By setting LC_COLLATE to C, we avoid accidentally depending
on libc behavior when using a different provider.
No behavior change in the backend, but it's possible that some
extensions will be affected. Such extensions should be updated to use
the pg_locale_t APIs.
Discussion: https://postgr.es/m/9875f7f9-50f1-4b5d-86fc-ee8b03e8c162@eisentraut.org
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
_bt_first need only store one ScanKeyData struct on the stack for the
purposes of building an IS NOT NULL key based on an implied NOT NULL
constraint. We don't need INDEX_MAX_KEYS-many ScanKeyData structs.
This saves us a little over 2KB in stack space. It's possible that this
has some performance benefit. It also seems simpler and more direct.
It isn't possible for more than a single index attribute to need its own
implied IS NOT NULL key: the first such attribute/IS NOT NULL key always
makes _bt_first stop adding additional boundary keys to startKeys[].
Using INDEX_MAX_KEYS-many ScanKeyData entries was (at best) misleading.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Mircea Cadariu <cadariu.mircea@gmail.com>
Discussion: https://postgr.es/m/CAH2-Wzm=1kJMSZhhTLoM5BPbwQNWxUj-ynOEh=89ptDZAVgauw@mail.gmail.com
This code used a NO_LZ4_SUPPORT() macro to issue an error in the code
paths where LZ4 [de]compression is attempted but the build does not
support it. This commit refactors the code to use a more flexible error
message so as it can be used for other compression methods, where the
method is given in input of macro.
Extracted from a larger patch by the same author.
Author: Nikhil Kumar Veldanda <veldanda.nikhilkumar17@gmail.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Discussion: https://postgr.es/m/CAFAfj_HX84EK4hyRYw50AOHOcdVi-+FFwAAPo7JHx4aShCvunQ@mail.gmail.com
The pgoutput plugin initializes optional parameters like "binary" with
default values at the start of processing. However, the "origin"
parameter was previously missed and left without explicit initialization.
Although the PGOutputData struct, which holds these settings,
is zero-initialized at allocation (resulting in publish_no_origin field
for "origin" parameter being false by default), this default was not
set explicitly, unlike other parameters.
This commit adds explicit initialization of the "origin" parameter to
ensure consistency and clarity in how defaults are handled.
Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Euler Taveira <euler@eulerto.com>
Discussion: https://postgr.es/m/d2790f10-238d-4cb5-a743-d9d2a9dd900f@oss.nttdata.com
The grammar was a little shaky and confusing here, so word-smith it
a bit. Also, adjust the comments in pg_ident.conf.sample to use the
same terminology as the SGML docs, in particular "DATABASE-USERNAME"
not "PG-USERNAME".
Back-patch appropriate subsets. I did not risk changing
pg_ident.conf.sample in released branches, but it still seems OK
to change it in v18.
Reported-by: Alexey Shishkin <alexey.shishkin@enterprisedb.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: David G. Johnston <david.g.johnston@gmail.com>
Discussion: https://postgr.es/m/175206279327.3157504.12519088928605422253@wrigleys.postgresql.org
Backpatch-through: 13
It's impossible to reach this case with either ra or rb being
WJB_DONE, because our earlier checks that the structure and
length of the inputs match should guarantee that we reach their
ends simultaneously. However, the comment completely fails to
explain this, and the Asserts don't cover it either. The comment
is pretty obscure anyway, so rewrite it, and extend the Asserts
to reject WJB_DONE.
This is only cosmetic, so no need for back-patch.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/0c623e8a204187b87b4736792398eaf1@postgrespro.ru
Because not every path through JsonbIteratorNext() sets val->type,
some compilers complain that compareJsonbContainers() is comparing
possibly-uninitialized values. The paths that don't set it return
WJB_DONE, WJB_END_ARRAY, or WJB_END_OBJECT, so it's clear by
manual inspection that the "(ra == rb)" code path is safe, and
indeed we aren't seeing warnings about that. But the (ra != rb)
case is much less obviously safe. In Assert-enabled builds it
seems that the asserts rejecting WJB_END_ARRAY and WJB_END_OBJECT
persuade gcc 15.x not to warn, which makes little sense because
it's impossible to believe that the compiler can prove of its
own accord that ra/rb aren't WJB_DONE here. (In fact they never
will be, so the code isn't wrong, but why is there no warning?)
Without Asserts, the appearance of warnings is quite unsurprising.
We discussed fixing this by converting those two Asserts into
pg_assume, but that seems not very satisfactory when it's so unclear
why the compiler is or isn't warning: the warning could easily
reappear with some other compiler version. Let's fix it in a less
magical, more future-proof way by changing JsonbIteratorNext()
so that it always does set val->type. The cost of that should be
pretty negligible, and it makes the function's API spec less squishy.
Reported-by: Erik Rijkers <er@xs4all.nl>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/988bf1bc-3f1f-99f3-bf98-222f1cd9dc5e@xs4all.nl
Discussion: https://postgr.es/m/0c623e8a204187b87b4736792398eaf1@postgrespro.ru
Backpatch-through: 13
If the system-name field of a pg_ident.conf line is a regex
containing capturing parentheses, you can write \1 in the
user-name field to represent the captured part of the system
name. But what happens if you write \1 more than once?
The only reasonable expectation IMO is that each \1 gets
replaced, but presently our code replaces only the first.
Fix that.
Also, improve the tests for this feature to exercise cases
where a non-empty string needs to be substituted for \1.
The previous testing didn't inspire much faith that it
was verifying correct operation of the substitution code.
Given the lack of field complaints about this, I don't
feel a need to back-patch.
Reported-by: David G. Johnston <david.g.johnston@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAKFQuwZu6kZ8ZPvJ3pWXig+6UX4nTVK-hdL_ZS3fSdps=RJQQQ@mail.gmail.com
The values of the "result" variables in these functions are
always integers; using a float8 variable accomplishes nothing
except to incur useless conversions to and from float. While
that wastes a few nanoseconds, these functions aren't all that
time-critical. But it seems worth fixing to remove possible
reader confusion.
Also, in the case of date2isoyear(), "result" is a very poorly
chosen variable name because it is *not* the function's result.
Rename it to "week", and do the same in date2isoweek() for
consistency.
Since this is mostly cosmetic, there seems little need
for back-patch.
Author: Sergey Fukanchik <s.fukanchik@postgrespro.ru>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/6323a-68726500-1-7def9d00@137821581
method_worker.c installed SignalHandlerForConfigReload, but it failed to
actually process reload requests. That hasn't yet produced any concrete
problem reports in terms of GUC changes it should have cared about in
v18, but it was inconsistent.
It did cause problems for a couple of patches in development that need
IO workers to react to ALTER SYSTEM + pg_reload_conf(). Fix extracted
from one of those patches.
Back-patch to 18.
Reported-by: Dmitry Dolgov <9erthalion6@gmail.com>
Discussion: https://postgr.es/m/sh5uqe4a4aqo5zkkpfy5fobe2rg2zzouctdjz7kou4t74c66ql%40yzpkxb7pgoxf
In an ancient ancestor of this code, the postmaster assigned IDs to IO
workers. Now it tracks them in an unordered array and doesn't know
their IDs, so it might be confusing to readers that it still referred to
their indexes as IDs.
No change in behavior, just variable name and error message cleanup.
Back-patch to 18.
Discussion: https://postgr.es/m/CA%2BhUKG%2BwbaZZ9Nwc_bTopm4f-7vDmCwLk80uKDHj9mq%2BUp0E%2Bg%40mail.gmail.com
Adopt PgAioXXX convention for pgaio module type names. Rename a
function that didn't use a pgaio_worker_ submodule prefix. Rename the
internal submit function's arguments to match the indirectly relevant
function pointer declaration and nearby examples. Rename the array of
handle IDs in PgAioSubmissionQueue to sqes, a term of art seen in the
systems it emulates, also clarifying that they're not IO handle
pointers as the old name might imply.
No change in behavior, just type, variable and function name cleanup.
Back-patch to 18.
Discussion: https://postgr.es/m/CA%2BhUKG%2BwbaZZ9Nwc_bTopm4f-7vDmCwLk80uKDHj9mq%2BUp0E%2Bg%40mail.gmail.com
getid() and putid(), which parse and deparse role names within ACL
input/output, applied isalnum() to see if a character within a role
name requires quoting. They did this even for non-ASCII characters,
which is problematic because the results would depend on encoding,
locale, and perhaps even platform. So it's possible that putid()
could elect not to quote some string that, later in some other
environment, getid() will decide is not a valid identifier, causing
dump/reload or similar failures.
To fix this in a way that won't risk interoperability problems
with unpatched versions, make getid() treat any non-ASCII as a
legitimate identifier character (hence not requiring quotes),
while making putid() treat any non-ASCII as requiring quoting.
We could remove the resulting excess quoting once we feel that
no unpatched servers remain in the wild, but that'll be years.
A lesser problem is that getid() did the wrong thing with an input
consisting of just two double quotes (""). That has to represent an
empty string, but getid() read it as a single double quote instead.
The case cannot arise in the normal course of events, since we don't
allow empty-string role names. But let's fix it while we're here.
Although we've not heard field reports of problems with non-ASCII
role names, there's clearly a hazard there, so back-patch to all
supported versions.
Reported-by: Peter Eisentraut <peter@eisentraut.org>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/3792884.1751492172@sss.pgh.pa.us
Backpatch-through: 13
This option, which is disabled by default, can be used to request
the checkpoint also flush dirty buffers of unlogged relations. As
with the MODE option, the server may consolidate the options for
concurrently requested checkpoints. For example, if one session
uses (FLUSH_UNLOGGED FALSE) and another uses (FLUSH_UNLOGGED TRUE),
the server may perform one checkpoint with FLUSH_UNLOGGED enabled.
Author: Christoph Berg <myon@debian.org>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Discussion: https://postgr.es/m/aDnaKTEf-0dLiEfz%40msg.df7cb.de
This option may be set to FAST (the default) to request the
checkpoint be completed as fast as possible, or SPREAD to request
the checkpoint be spread over a longer interval (based on the
checkpoint-related configuration parameters). Note that the server
may consolidate the options for concurrently requested checkpoints.
For example, if one session requests a "fast" checkpoint and
another requests a "spread" checkpoint, the server may perform one
"fast" checkpoint.
Author: Christoph Berg <myon@debian.org>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Discussion: https://postgr.es/m/aDnaKTEf-0dLiEfz%40msg.df7cb.de
This commit adds the boilerplate code for supporting a list of
options in CHECKPOINT commands. No actual options are supported
yet, but follow-up commits will add support for MODE and
FLUSH_UNLOGGED. While at it, this commit refactors the code for
executing CHECKPOINT commands to its own function since it's about
to become significantly larger.
Author: Christoph Berg <myon@debian.org>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Discussion: https://postgr.es/m/aDnaKTEf-0dLiEfz%40msg.df7cb.de
The new name more accurately reflects the effects of this flag on a
requested checkpoint. Checkpoint-related log messages (i.e., those
controlled by the log_checkpoints configuration parameter) will now
say "fast" instead of "immediate", too. Likewise, references to
"immediate" checkpoints in the documentation have been updated to
say "fast". This is preparatory work for a follow-up commit that
will add a MODE option to the CHECKPOINT command.
Author: Christoph Berg <myon@debian.org>
Discussion: https://postgr.es/m/aDnaKTEf-0dLiEfz%40msg.df7cb.de
The new name more accurately relects the effects of this flag on a
requested checkpoint. Checkpoint-related log messages (i.e., those
controlled by the log_checkpoints configuration parameter) will now
say "flush-unlogged" instead of "flush-all", too. This is
preparatory work for a follow-up commit that will add a
FLUSH_UNLOGGED option to the CHECKPOINT command.
Author: Christoph Berg <myon@debian.org>
Discussion: https://postgr.es/m/aDnaKTEf-0dLiEfz%40msg.df7cb.de
Previously, the check_hook functions for max_slot_wal_keep_size and
idle_replication_slot_timeout would incorrectly raise an ERROR for values
set in postgresql.conf during upgrade, even though those values were not
actively used in the upgrade process.
To prevent logical slot invalidation during upgrade, we used to set
special values for these GUCs. Now, instead of relying on those values, we
directly prevent WAL removal and logical slot invalidation caused by
max_slot_wal_keep_size and idle_replication_slot_timeout.
Note: PostgreSQL 17 does not include the idle_replication_slot_timeout
GUC, so related changes were not backported.
BUG #18979
Reported-by: jorsol <jorsol@gmail.com>
Author: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed by: vignesh C <vignesh21@gmail.com>
Reviewed by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Backpatch-through: 17, where it was introduced
Discussion: https://postgr.es/m/219561.1751826409@sss.pgh.pa.us
Discussion: https://postgr.es/m/18979-a1b7fdbb7cd181c6@postgresql.org
This commit updates the documentation to clarify that "idle" in
idle_replication_slot_timeout means the replication slot is inactive,
that is, not currently used by any replication connection.
Without this clarification, "idle" could be misinterpreted to mean
that the slot is not advancing or that no data is being streamed,
even if a connection exists.
Back-patch to v18 where idle_replication_slot_timeout was added.
Author: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: David G. Johnston <david.g.johnston@gmail.com>
Reviewed-by: Gunnar Morling <gunnar.morling@googlemail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/CADGJaX_0+FTguWpNSpgVWYQP_7MhoO0D8=cp4XozSQgaZ40Odw@mail.gmail.com
Backpatch-through: 18
Previously, the idle_replication_slot_timeout parameter used minutes
as its unit, based on the assumption that values would typically exceed
one minute in production environments. However, this caused unexpected
behavior: specifying a value below 30 seconds would round down to 0,
effectively disabling the timeout. This could be surprising to users.
To allow finer-grained control and avoid such confusion, this commit changes
the unit of idle_replication_slot_timeout to seconds. Larger values can
still be specified easily using standard time suffixes, for example,
'24h' for 24 hours.
Back-patch to v18 where idle_replication_slot_timeout was added.
Reported-by: Gunnar Morling <gunnar.morling@googlemail.com>
Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: David G. Johnston <david.g.johnston@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CADGJaX_0+FTguWpNSpgVWYQP_7MhoO0D8=cp4XozSQgaZ40Odw@mail.gmail.com
Backpatch-through: 18
This commit adds a new system view that provides information about
entries in the dynamic shared memory (DSM) registry. Specifically,
it returns the name, type, and size of each entry. Note that since
we cannot discover the size of dynamic shared memory areas (DSAs)
and hash tables backed by DSAs (dshashes) without first attaching
to them, the size column is left as NULL for those.
Bumps catversion.
Author: Florents Tselai <florents.tselai@gmail.com>
Reviewed-by: Sungwoo Chang <swchangdev@gmail.com>
Discussion: https://postgr.es/m/4D445D3E-81C5-4135-95BB-D414204A0AB4%40gmail.com
xmltotext_with_options() did not consider the possibility that
pg_xml_init() could fail --- most likely due to OOM. If that
happened, the already-parsed xmlDoc structure would be leaked.
Oversight in commit 483bdb2af.
Bug: #18981
Author: Dmitry Kovalenko <d.kovalenko@postgrespro.ru>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18981-9bc3c80f107ae925@postgresql.org
Backpatch-through: 16
By default io_uring creates a shared memory mapping for each io_uring
instance, leading to a large number of memory mappings. Unfortunately a large
number of memory mappings slows things down, backend exit is particularly
affected. To address that, newer kernels (6.5) support using user-provided
memory for the memory. By putting the relevant memory into shared memory we
don't need any additional mappings.
On a system with a new enough kernel and liburing, there is no discernible
overhead when doing a pgbench -S -C anymore.
Reported-by: MARK CALLAGHAN <mdcallag@gmail.com>
Reviewed-by: "Burd, Greg" <greg@burd.me>
Reviewed-by: Jim Nasby <jnasby@upgrade.com>
Discussion: https://postgr.es/m/CAFbpF8OA44_UG+RYJcWH9WjF7E3GA6gka3gvH6nsrSnEe9H0NA@mail.gmail.com
Backpatch-through: 18
For an ordered Append or MergeAppend, we need to inject an explicit
sort into any subpath that is not already well enough ordered.
Currently, only explicit full sorts are considered; incremental sorts
are not yet taken into account.
In this patch, for subpaths of an ordered Append or MergeAppend, we
choose to use explicit incremental sort if it is enabled and there are
presorted keys.
The rationale is based on the assumption that incremental sort is
always faster than full sort when there are presorted keys, a premise
that has been applied in various parts of the code. In addition, the
current cost model tends to favor incremental sort as being cheaper
than full sort in the presence of presorted keys, making it reasonable
not to consider full sort in such cases.
No backpatch as this could result in plan changes.
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/CAMbWs4_V7a2enTR+T3pOY_YZ-FU8ZsFYym2swOz4jNMqmSgyuw@mail.gmail.com
Functions to bootstrap and zero pages in various SLRU callers were
fairly duplicative. We can slash almost two hundred lines with a couple
of simple helpers:
- SimpleLruZeroAndWritePage: Does the equivalent of SimpleLruZeroPage
followed by flushing the page to disk
- XLogSimpleInsertInt64: Does a XLogBeginInsert followed by XLogInsert
of a trivial record whose data is just an int64.
Author: Evgeny Voropaev <evgeny.voropaev@tantorlabs.com>
Reviewed by: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed by: Andrey Borodin <x4mmm@yandex-team.ru>
Reviewed by: Aleksander Alekseev <aleksander@timescale.com>
Discussion: https://www.postgresql.org/message-id/flat/97820ce8-a1cd-407f-a02b-47368fadb14b%40tantorlabs.com
This commit standardizes the output format for LSNs to ensure consistent
representation across various tools and messages. Previously, LSNs were
inconsistently printed as `%X/%X` in some contexts, while others used
zero-padding. This often led to confusion when comparing.
To address this, the LSN format is now uniformly set to `%X/%08X`,
ensuring the lower 32-bit part is always zero-padded to eight
hexadecimal digits.
Author: Japin Li <japinli@hotmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Discussion: https://postgr.es/m/ME0P300MB0445CA53CA0E4B8C1879AF84B641A@ME0P300MB0445.AUSP300.PROD.OUTLOOK.COM
This refactoring is a follow-up of the work done in 5a1dfde833, that
has switched 2PC file names to use FullTransactionIds when written on
disk. This will help with the integration of a follow-up solution
related to the handling of two-phase files during recovery, to address
older defects while reading these from disk after a crash.
This change is useful in itself as it reduces the need to build the
file names from epoch numbers and TransactionIds, because we can use
directly FullTransactionIds from which the 2PC file names are guessed.
So this avoids a lot of back-and-forth between the FullTransactionIds
retrieved from the file names and how these are passed around in the
internal 2PC logic.
Note that the core of the change is the use of a FullTransactionId
instead of a TransactionId in GlobalTransactionData, that tracks 2PC
file information in shared memory. The change in TwoPhaseCallback makes
this commit unfit for stable branches.
Noah has contributed a good chunk of this patch. I have spent some time
on it as well while working on the issues with two-phase state files and
recovery.
Author: Noah Misch <noah@leadboat.com>
Co-Authored-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/Z5sd5O9JO7NYNK-C@paquier.xyz
Discussion: https://postgr.es/m/20250116205254.65.nmisch@google.com
Attempting to use commit timestamps during bootstrapping leads to an
assertion failure, that can be reached for example with an initdb -c
that enables track_commit_timestamp. It makes little sense to register
a commit timestamp for a BootstrapTransactionId, so let's disable the
activation of the module in this case.
This problem has been independently reported once by each author of this
commit. Each author has proposed basically the same patch, relying on
IsBootstrapProcessingMode() to skip the use of commit_ts during
bootstrap. The test addition is a suggestion by me, and is applied down
to v16.
Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Author: Andy Fan <zhihuifan1213@163.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/OSCPR01MB14966FF9E4C4145F37B937E52F5102@OSCPR01MB14966.jpnprd01.prod.outlook.com
Discussion: https://postgr.es/m/87plejmnpy.fsf@163.com
Backpatch-through: 13
Previously, truncating a temporary relation required scanning the entire
local buffer pool once per relation fork to invalidate buffers. This could
be slow, especially with a large local buffers, as the scan was repeated
multiple times.
A similar issue with regular tables (shared buffers) was addressed in
commit 6d05086c0a by scanning the buffer pool only once for all forks.
This commit applies the same optimization to temporary relations,
improving truncation performance.
Author: Daniil Davydov <3danissimo@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: Maxim Orlov <orlovmg@gmail.com>
Discussion: https://postgr.es/m/CAJDiXggNqsJOH7C5co4jA8nDk8vw-=sokyh5s1_TENWnC6Ofcg@mail.gmail.com
If, after removal of useless null-constant arguments, a CoalesceExpr
has exactly one remaining argument, we can just take that argument as
the result, without bothering to wrap a new CoalesceExpr around it.
This isn't likely to produce any great improvement in runtime per se,
but it can lead to better plans since the planner no longer has to
treat the expression as non-strict.
However, there were a few regression test cases that intentionally
wrote COALESCE(x) as a shorthand way of creating a non-strict
subexpression. To avoid ruining the intent of those tests, write
COALESCE(x,x) instead. (If anyone ever proposes de-duplicating
COALESCE arguments, we'll need another iteration of this arms race.
But it seems pretty unlikely that such an optimization would be
worthwhile.)
Author: Maksim Milyutin <maksim.milyutin@tantorlabs.ru>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/8e8573c3-1411-448d-877e-53258b7b2be0@tantorlabs.ru
Previous commits invented timestamp2timestamptz_opt_overflow,
date2timestamp_opt_overflow, and date2timestamptz_opt_overflow
functions to perform non-error-throwing conversions between
datetime types. This patch completes the set by adding
timestamp2date_opt_overflow, timestamptz2date_opt_overflow,
and timestamptz2timestamp_opt_overflow.
In addition, adjust timestamp2timestamptz_opt_overflow so that it
doesn't throw error if timestamp2tm fails, but treats that as an
overflow case. The situation probably can't arise except with an
invalid timestamp value, and I can't think of a way that that would
happen except data corruption. However, it's pretty silly to have a
function whose entire reason for existence is to not throw errors for
out-of-range inputs nonetheless throw an error for out-of-range input.
The new APIs are not used in this patch, but will be needed in
upcoming btree_gin changes.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Arseniy Mukhin <arseniy.mukhin.dev@gmail.com>
Discussion: https://postgr.es/m/262624.1738460652@sss.pgh.pa.us
Commits 8319e5cb5 et al missed the fact that ATPostAlterTypeCleanup
contains three calls to ATPostAlterTypeParse, and the other two
also need protection against passing a relid that we don't yet
have lock on. Add similar logic to those code paths, and add
some test cases demonstrating the need for it.
In v18 and master, the test cases demonstrate that there's a
behavioral discrepancy between stored generated columns and virtual
generated columns: we disallow changing the expression of a stored
column if it's used in any composite-type columns, but not that of
a virtual column. Since the expression isn't actually relevant to
either sort of composite-type usage, this prohibition seems
unnecessary; but changing it is a matter for separate discussion.
For now we are just documenting the existing behavior.
Reported-by: jian he <jian.universality@gmail.com>
Author: jian he <jian.universality@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: CACJufxGKJtGNRRSXfwMW9SqVOPEMdP17BJ7DsBf=tNsv9pWU9g@mail.gmail.com
Backpatch-through: 13
If certain constraint characteristic clauses (NO INHERIT, NOT VALID, NOT
ENFORCED) are given to CREATE CONSTRAINT TRIGGER, the resulting error
message is
ERROR: TRIGGER constraints cannot be marked NO INHERIT
which is a bit silly, because these aren't "constraints of type
TRIGGER". Hardcode a better error message to prevent it. This is a
cosmetic fix for quite a fringe problem with no known complaints from
users, so no backpatch.
While at it, silently accept ENFORCED if given.
Author: Amul Sul <sulamul@gmail.com>
Reviewed-by: jian he <jian.universality@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Discussion: https://postgr.es/m/CAAJ_b97hd-jMTS7AjgU6TDBCzDx_KyuKxG+K-DtYmOieg+giyQ@mail.gmail.com
Discussion: https://postgr.es/m/CACJufxHSp2puxP=q8ZtUGL1F+heapnzqFBZy5ZNGUjUgwjBqTQ@mail.gmail.com
AlterDomainStmt.subtype used characters for its subtypes of commands,
SET|DROP DEFAULT|NOT NULL and ADD|DROP|VALIDATE CONSTRAINT, which were
hardcoded in a couple of places of the code. The code is improved by
using an enum instead, with the same character values as the original
code.
Note that the field was documented in parsenodes.h and that it forgot to
mention 'V' (VALIDATE CONSTRAINT).
Author: Quan Zongliang <quanzongliang@yeah.net>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: wenhui qiu <qiuwenhuifx@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Discussion: https://postgr.es/m/41ff310b-16bd-44b9-a3ef-97e20f14b709@yeah.net
The COPY FROM command now accepts a non-negative integer for the HEADER option,
allowing multiple header lines to be skipped. This is useful when the input
contains multi-line headers that should be ignored during data import.
Author: Shinya Kato <shinya11.kato@gmail.com>
Co-authored-by: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Yugo Nagata <nagata@sraoss.co.jp>
Discussion: https://postgr.es/m/CAOzEurRPxfzbxqeOPF_AGnAUOYf=Wk0we+1LQomPNUNtyZGBZw@mail.gmail.com
Currently check_recovery_target_timeline() converts any value that is
not "current", "latest", or a valid integer to 0. So, for example, the
following configuration added to postgresql.conf followed by a startup:
recovery_target_timeline = 'bogus'
recovery_target_timeline = '9999999999'
... results in the following error patterns:
FATAL: 22023: recovery target timeline 0 does not exist
FATAL: 22023: recovery target timeline 1410065407 does not exist
This is confusing, because the server does not reflect the intention of
the user, and just reports incorrect data unrelated to the GUC.
The origin of the problem is that we do not perform a range check in the
GUC value passed-in for recovery_target_timeline. This commit improves
the situation by using strtou64() and by providing stricter range
checks. Some test cases are added for the cases of an incorrect, an
upper-bound and a lower-bound timeline value, checking the sanity of the
reports based on the contents of the server logs.
Author: David Steele <david@pgmasters.net>
Discussion: https://postgr.es/m/e5d472c7-e9be-4710-8dc4-ebe721b62cea@pgbackrest.org
Currently, we do not support Memoize for SEMI and ANTI joins because
nested loop SEMI/ANTI joins do not scan the inner relation to
completion, which prevents Memoize from marking the cache entry as
complete. One might argue that we could mark the cache entry as
complete after fetching the first inner tuple, but that would not be
safe: if the first inner tuple and the current outer tuple do not
satisfy the join clauses, a second inner tuple matching the parameters
would find the cache entry already marked as complete.
However, if the inner side is provably unique, this issue doesn't
arise, since there would be no second matching tuple. That said, this
doesn't help in the case of SEMI joins, because a SEMI join with a
provably unique inner side would already have been reduced to an inner
join by reduce_unique_semijoins.
Therefore, in this patch, we check whether the inner relation is
provably unique for ANTI joins and enable the use of Memoize in such
cases.
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: wenhui qiu <qiuwenhuifx@gmail.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Discussion: https://postgr.es/m/CAMbWs48FdLiMNrmJL-g6mDvoQVt0yNyJAqMkv4e2Pk-5GKCZLA@mail.gmail.com
This routine has come as a useful piece to be able to know the list of
injection points currently attached in a system. One area would be to
use it in a set-returning function, or just let out-of-core code play
with it.
This hides the internals of the shared memory array lookup holding the
information about the injection points (point name, library and function
name), allocating the result in a palloc'd List consumable by the
caller.
Reviewed-by: Jeff Davis <pgsql@j-davis.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Rahila Syed <rahilasyed90@gmail.com>
Discussion: https://postgr.es/m/Z_xYkA21KyLEHvWR@paquier.xyz
Discussion: https://postgr.es/m/aBG2rPwl3GE7m1-Q@paquier.xyz
Presently, the dynamic shared memory (DSM) registry only provides
GetNamedDSMSegment(), which allocates a fixed-size segment. To use
the DSM registry for more sophisticated things like dynamic shared
memory areas (DSAs) or a hash table backed by a DSA (dshash), users
need to create a DSM segment that stores various handles and LWLock
tranche IDs and to write fairly complicated initialization code.
Furthermore, there is likely little variation in this
initialization code between libraries.
This commit introduces functions that simplify allocating a DSA or
dshash within the DSM registry. These functions are very similar
to GetNamedDSMSegment(). Notable differences include the lack of
an initialization callback parameter and the prohibition of calling
the functions more than once for a given entry in each backend
(which should be trivially avoidable in most circumstances). While
at it, this commit bumps the maximum DSM registry entry name length
from 63 bytes to 127 bytes.
Also note that even though one could presumably detach/destroy the
DSAs and dshashes created in the registry, such use-cases are not
yet well-supported, if for no other reason than the associated DSM
registry entries cannot be removed. Adding such support is left as
a future exercise.
The test_dsm_registry test module contains tests for the new
functions and also serves as a complete usage example.
Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Florents Tselai <florents.tselai@gmail.com>
Reviewed-by: Rahila Syed <rahilasyed90@gmail.com>
Discussion: https://postgr.es/m/aEC8HGy2tRQjZg_8%40nathan
Restore nbtree preprocessing comments describing how we mark nbtree row
compare members required to how they were prior to 2016 bugfix commit
a298a1e0.
Oversight in commit bd3f59fd, which made nbtree preprocessing revert to
the original 2006 rules, but neglected to revert these comments.
Backpatch-through: 18
The array-based variant of width_bucket() has always accepted NaN
inputs, treating them as equal but larger than any non-NaN,
as we do in ordinary comparisons. But up to now, the four-argument
variants threw errors for a NaN operand. This is inconsistent
and unnecessary, since we can perfectly well regard NaN as falling
after the last bucket.
We do still throw error for NaN or infinity histogram-bound inputs,
since there's no way to compute sensible bucket boundaries.
Arguably this is a bug fix, but given the lack of field complaints
I'm content to fix it in master.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Discussion: https://postgr.es/m/2822872.1750540911@sss.pgh.pa.us
Trying to alter a constraint so that it becomes NOT VALID results in an
error that assumes the constraint is a foreign key. This is potentially
wrong, so give a more generic error message.
While at it, give CREATE CONSTRAINT TRIGGER a better error message as
well.
Co-authored-by: jian he <jian.universality@gmail.com>
Co-authored-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Co-authored-by: Álvaro Herrera <alvherre@kurilemu.de>
Co-authored-by: Amul Sul <sulamul@gmail.com>
Discussion: https://postgr.es/m/CACJufxHSp2puxP=q8ZtUGL1F+heapnzqFBZy5ZNGUjUgwjBqTQ@mail.gmail.com
Recent nbtree bugfix commit 5f4d98d4 added a special case to the code
that sets up a page-level prefix of keys that are definitely satisfied
by every tuple on the page: whenever _bt_set_startikey reached a row
compare key, we'd refuse to apply the pstate.forcenonrequired behavior
in scans where that usually happens (scans with a higher-order array
key). That hack made the scan avoid essentially the same infinite
cycling behavior that also affected nbtree scans with redundant keys
(keys that preprocessing could not eliminate) prior to commit f09816a0.
There are now serious doubts about this row compare workaround.
Testing has shown that a scan with a row compare key and an array key
could still read the same leaf page twice (without the scan's direction
changing), which isn't supposed to be possible following the SAOP
enhancements added by Postgres 17 commit 5bf748b8. Also, we still
allowed a required row compare key to be used with forcenonrequired mode
when its header key happened to be beyond the pstate.ikey set by
_bt_set_startikey, which was complicated and brittle.
The underlying problem was that row compares had inconsistent rules
around how scans start (which keys can be used for initial positioning
purposes) and how scans end (which keys can set continuescan=false).
Quals with redundant keys that could not be eliminated by preprocessing
also had that same quality to them prior to today's bugfix f09816a0. It
now seems prudent to bring row compare keys in line with the new charter
for required keys, by making the start and end rules symmetric.
This commit fixes two points of disagreement between _bt_first and
_bt_check_rowcompare. Firstly, _bt_check_rowcompare was capable of
ending the scan at the point where it needed to compare an ISNULL-marked
row compare member that came immediately after a required row compare
member. _bt_first now has symmetric handling for NULL row compares.
Secondly, _bt_first had its own ideas about which keys were safe to use
for initial positioning purposes. It could use fewer or more keys than
_bt_check_rowcompare. _bt_first now uses the same requiredness markings
as _bt_check_rowcompare for this.
Now that _bt_first and _bt_check_rowcompare agree on how to start and
end scans, we can get rid of the forcenonrequired special case, without
any risk of infinite cycling. This approach also makes row compare keys
behave more like regular scalar keys, particularly within _bt_first.
Fixing these inconsistencies necessitates dealing with a related issue
with the way that row compares were marked required by preprocessing: we
didn't mark any lower-order row members required following 2016 bugfix
commit a298a1e0. That approach was over broad. The bug in question was
actually an oversight in how _bt_check_rowcompare dealt with tuple NULL
values that failed to satisfy a scan key marked required in the opposite
scan direction (it was a bug in 2011 commits 6980f817 and 882368e8, not
a bug in 2006 commit 3a0a16cb). Go back to marking row compare members
as required using the original 2006 rules, and fix the 2016 bug in a
more principled way: by limiting use of the "set continuescan=false with
a key required in the opposite scan direction upon encountering a NULL
tuple value" optimization to the first/most significant row member key.
While it isn't safe to use an implied IS NOT NULL qualifier to end the
scan when it comes from a required lower-order row compare member key,
it _is_ generally safe for such a required member key to end the scan --
provided the key is marked required in the _current_ scan direction.
This fixes what was arguably an oversight in either commit 5f4d98d4 or
commit 8a510275. It is a direct follow-up to today's commit f09816a0.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Discussion: https://postgr.es/m/CAH2-Wz=pcijHL_mA0_TJ5LiTB28QpQ0cGtT-ccFV=KzuunNDDQ@mail.gmail.com
Backpatch-through: 18
nbtree preprocessing's handling of redundant (and contradictory) keys
created problems for scans with = arrays. It was just about possible
for a scan with an = array key and one or more redundant keys (keys that
preprocessing could not eliminate due an incomplete opfamily and a
cross-type key) to get stuck. Testing has shown that infinite cycling
where the scan never manages to make forward progress was possible.
This could happen when the scan's arrays were reset in _bt_readpage's
forcenonrequired=true path (added by bugfix commit 5f4d98d4) when the
arrays weren't at least advanced up to the same point that they were in
at the start of the _bt_readpage call. Earlier redundant keys prevented
the finaltup call to _bt_advance_array_keys from reaching lower-order
keys that needed to be used to sufficiently advance the scan's arrays.
To fix, make preprocessing leave the scan's keys in a state that is as
close as possible to how it'll usually leave them (in the common case
where there's no redundant keys that preprocessing failed to eliminate).
Now nbtree preprocessing _reliably_ leaves behind at most one required
>/>= key per index column, and at most one required </<= key per index
column. Columns that have one or more = keys that are eligible to be
marked required (based on the traditional rules) prioritize the = keys
over redundant inequality keys; they'll _reliably_ be left with only one
of the = keys as the index column's only required key.
Keys that are not marked required (whether due to the new preprocessing
step running or for some other reason) are relocated to the end of the
so->keyData[] array as needed. That way they'll always be evaluated
after the scan's required keys, and so cannot prevent code in places
like _bt_advance_array_keys and _bt_first from reaching a required key.
Also teach _bt_first to decide which initial positioning keys to use
based on the same requiredness markings that have long been used by
_bt_checkkeys/_bt_advance_array_keys. This is a necessary condition for
reliably avoiding infinite cycling. _bt_advance_array_keys expects to
be able to reason about what'll happen in the next _bt_first call should
it start another primitive index scan, by evaluating inequality keys
that were marked required in the opposite-to-scan scan direction only.
Now everybody (_bt_first, _bt_checkkeys, and _bt_advance_array_keys)
will always agree on which exact key will be used on each index column
to start and/or end the scan (except when row compare keys are involved,
which have similar problems not addressed by this commit).
An upcoming commit will finish off the work started by this commit by
harmonizing how _bt_first, _bt_checkkeys, and _bt_advance_array_keys
apply row compare keys to start and end scans.
This fixes what was arguably an oversight in either commit 5f4d98d4 or
commit 8a510275.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Discussion: https://postgr.es/m/CAH2-Wz=ds4M+3NXMgwxYxqU8MULaLf696_v5g=9WNmWL2=Uo2A@mail.gmail.com
Backpatch-through: 18
The previous minimum was to maintain support for Python 3.5, but we
now require Python 3.6 anyway (commit 45363fca63), so that reason is
obsolete. A small raise to Meson 0.57 allows getting rid of a fair
amount of version conditionals and silences some future-deprecated
warnings.
With the version bump, the following deprecation warnings appeared and
are fixed:
WARNING: Project targets '>=0.57' but uses feature deprecated since '0.55.0': ExternalProgram.path. use ExternalProgram.full_path() instead
WARNING: Project targets '>=0.57' but uses feature deprecated since '0.56.0': meson.build_root. use meson.project_build_root() or meson.global_build_root() instead.
It turns out that meson 0.57.0 and 0.57.1 are buggy for our use, so
the minimum is actually set to 0.57.2. This is specific to this
version series; in the future we won't necessarily need to be this
precise.
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/flat/42e13eb0-862a-441e-8d84-4f0fd5f6def0%40eisentraut.org
Commit c120550edb optimized the vacuuming of relations without
indexes (a.k.a. one-pass strategy) by directly marking dead item IDs
as LP_UNUSED. However, the periodic FSM vacuum was still checking if
dead item IDs had been marked as LP_DEAD when attempting to vacuum the
FSM every VACUUM_FSM_EVERY_PAGES blocks. This condition was never met
due to the optimization, resulting in missed FSM vacuum
opportunities.
This commit modifies the periodic FSM vacuum condition to use the
number of tuples deleted during HOT pruning. This count includes items
marked as either LP_UNUSED or LP_REDIRECT, both of which are expected
to result in new free space to report.
Back-patch to v17 where the vacuum optimization for tables with no
indexes was introduced.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAD21AoBL8m6B9GSzQfYxVaEgvD7-Kr3AJaS-hJPHC+avm-29zw@mail.gmail.com
Backpatch-through: 17
This commit moves all the routines related to the bytea data type into
its own new file, called bytea.c, clearing some of the bloat in
varlena.c. This includes the routines for:
- Input, output, receive and send
- Comparison
- Casts to integer types
- bytea-specific functions
The internals of the routines moved here are unchanged, with one
exception. This comes with a twist in bytea_string_agg_transfn(), where
the call to makeStringAggState() is replaced by the internals of this
routine, still located in varlena.c. This simplifies the move to the
new file by not having to expose makeStringAggState().
Author: Aleksander Alekseev <aleksander@timescale.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/CAJ7c6TMPVPJ5DL447zDz5ydctB8OmuviURtSwd=PHCRFEPDEAQ@mail.gmail.com
Prior to this patch, every FETCH call would generate a unique queryId
with a different size specified. Depending on the workloads, this could
lead to a significant bloat in pg_stat_statements, as repeatedly calling
a specific cursor would result in a new queryId each time. For example,
FETCH 1 c1; and FETCH 2 c1; would produce different queryIds.
This patch improves the situation by normalizing the fetch size, so as
semantically similar statements generate the same queryId. As a result,
statements like the below, which differ syntactically but have the same
effect, will now share a single queryId:
FETCH FROM c1
FETCH NEXT c1
FETCH 1 c1
In order to do a normalization based on the keyword used in FETCH,
FetchStmt is tweaked with a new FetchDirectionKeywords. This matters
for "howMany", which could be set to a negative value depending on the
direction, and we want to normalize the queries with enough information
about the direction keywords provided, including RELATIVE, ABSOLUTE or
all the ALL variants.
Author: Sami Imseih <samimseih@gmail.com>
Discussion: https://postgr.es/m/CAA5RZ0tA6LbHCg2qSS+KuM850BZC_+ZgHV7Ug6BXw22TNyF+MA@mail.gmail.com
The existing code assumed that O_RDONLY is defined as 0, but this is
not required by POSIX and is not true on GNU Hurd. We can avoid
the assumption by relying on O_ACCMODE to mask the fcntl() result.
(Hopefully, all supported platforms define that.)
Author: Michael Banck <mbanck@gmx.net>
Co-authored-by: Samuel Thibault
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/6862e8d1.050a0220.194b8d.76fa@mx.google.com
Discussion: https://postgr.es/m/68480868.5d0a0220.1e214d.68a6@mx.google.com
Backpatch-through: 13
Previously, pattern matching and case mapping behavior branched based
on the provider. Refactor to use a method table, which is less
error-prone.
This is also a step toward multiple provider versions, which we may
want to support in the future.
Reviewed-by: Andreas Karlsson <andreas@proxel.se>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/2830211e1b6e6a2e26d845780b03e125281ea17b.camel%40j-davis.com
When querying NUMA status of pages in shared memory, we need to touch
the memory first to get valid results. This may trigger valgrind
reports, because some of the memory (e.g. unpinned buffers) may be
marked as noaccess.
Solved by adding a valgrind suppresion. An alternative would be to
adjust the access/noaccess status before touching the memory, but that
seems far too invasive. It would require all those places to have
detailed knowledge of what the shared memory stores.
The pg_numa_touch_mem_if_required() macro is replaced with a function.
Macros are invisible to suppressions, so it'd have to suppress reports
for the caller - e.g. pg_get_shmem_allocations_numa(). So we'd suppress
reports for the whole function, and that seems to heavy-handed. It might
easily hide other valid issues.
Reviewed-by: Christoph Berg <myon@debian.org>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/aEtDozLmtZddARdB@msg.df7cb.de
Backpatch-through: 18
This commit fixes some defects in the backend's xml.c, found upon
inspection of the internals of libxml2:
- xmlEncodeSpecialChars() can fail on malloc(), returning NULL back to
the caller. xmltext() assumed that this could never happen. Like other
code paths, a TRY/CATCH block is added there, covering also the fact
that cstring_to_text_with_len() could fail a memory allocation, where
the backend would miss to free the buffer allocated by
xmlEncodeSpecialChars().
- Some libxml2 routines called in xmlelement() can return NULL, like
xmlAddChildList() or xmlTextWriterStartElement(). Dedicated errors are
added for them.
- xml_xmlnodetoxmltype() missed that xmlXPathCastNodeToString() can fail
on an allocation failure. In this case, the call can just be moved to
the existing TRY/CATCH block.
All these code paths would cause the server to crash. As this is
unlikely a problem in practice, no backpatch is done. Jim and I have
caught these defects, not sure who has scored the most. The contrib
module xml2/ has similar defects, which will be addressed in a separate
change.
Reported-by: Jim Jones <jim.jones@uni-muenster.de>
Reviewed-by: Jim Jones <jim.jones@uni-muenster.de>
Discussion: https://postgr.es/m/aEEingzOta_S_Nu7@paquier.xyz
This provides a convenient way to look up a database's OID. For
example, the query
SELECT * FROM pg_shdepend
WHERE dbid = (SELECT oid FROM pg_database
WHERE datname = current_database());
can now be simplified to
SELECT * FROM pg_shdepend
WHERE dbid = current_database()::regdatabase;
Like the regrole type, regdatabase has cluster-wide scope, so we
disallow regdatabase constants from appearing in stored
expressions.
Bumps catversion.
Author: Ian Lawrence Barwick <barwick@gmail.com>
Reviewed-by: Greg Sabino Mullane <htamfids@gmail.com>
Reviewed-by: Jian He <jian.universality@gmail.com>
Reviewed-by: Fabrízio de Royes Mello <fabriziomello@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/aBpjJhyHpM2LYcG0%40nathan
This commit refactors the vacuum routines that rely on VacuumParams,
adding const markers where necessary to force a new policy in the code.
This structure should not use a pointer as it may be used across
multiple relations, and its contents should never be updated.
vacuum_rel() stands as an exception as it touches the "index_cleanup"
and "truncate" options.
VacuumParams has been introduced in 0d83138974, and 661643deda has
fixed a bug impacting VACUUM operating on multiple relations. The
changes done in tableam.h break ABI compatibility, so this commit can
only happen on HEAD.
Author: Shihao Zhong <zhong950419@gmail.com>
Co-authored-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Discussion: https://postgr.es/m/CAGRkXqTo+aK=GTy5pSc-9cy8H2F2TJvcrZ-zXEiNJj93np1UUw@mail.gmail.com
In the wake of commit a16ef313f, we need to deal with more cases
involving PlaceHolderVars in NestLoopParams than we did before.
For one thing, a16ef313f was incorrect to suppose that we could
rely on the required-outer relids of the lefthand path to decide
placement of nestloop-parameter PHVs. As Richard Guo argued at
the time, we must look at the required-outer relids of the join
path itself.
For another, we have to apply replace_nestloop_params() to such
a PHV's expression, in case it contains references to values that
will be supplied from NestLoopParams of higher-level nestloops.
For another, we need to be more careful about the phnullingrels
of the PHV than we were being. identify_current_nestloop_params
only bothered to ensure that the phnullingrels didn't contain
"too many" relids, but now it has to be exact, because setrefs.c
will apply both NRM_SUBSET and NRM_SUPERSET checks in different
places. We can compute the correct relids by determining the
set of outer joins that should be able to null the PHV and then
subtracting whatever's been applied at or below this join.
Do the same for plain Vars, too. (This should make it possible
to use NRM_EQUAL to process nestloop params in setrefs.c, but
I won't risk making such a change in v18 now.)
Lastly, if a nestloop parameter PHV was pulled up out of a subquery
and it contains a subquery that was originally pushed down from this
query level, then that will still be represented as a SubLink, because
SS_process_sublinks won't recurse into outer PHVs, so it didn't get
transformed during expression preprocessing in the subquery. We can
substitute the version of the PHV's expression appearing in its
PlaceHolderInfo to ensure that that preprocessing has happened.
(Seems like this processing sequence could stand to be redesigned,
but again, late in v18 development is not the time for that.)
It's not very clear to me why the old have_dangerous_phv join-order
restriction prevented us from seeing the last three of these problems.
But given the lack of field complaints, it must have done so.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18953-1c9883a9d4afeb30@postgresql.org
Sometimes a table's constraint may depend on a column of another
table, so that we have to update the constraint when changing the
referenced column's type. We need to have lock on the constraint's
table to do that. ATPostAlterTypeCleanup believed that this case
was only possible for FOREIGN KEY constraints, but it's wrong at
least for CHECK and EXCLUDE constraints; and in general, we'd
probably need exclusive lock to alter any sort of constraint.
So just remove the contype check and acquire lock for any other
table. This prevents a "you don't have lock" assertion failure,
though no ill effect is observed in production builds.
We'll error out later anyway because we don't presently support
physically altering column types within stored composite columns.
But the catalog-munging is basically all there, so we may as well
make that part work.
Bug: #18970
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Diagnosed-by: jian he <jian.universality@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18970-a7d1cfe1f8d5d8d9@postgresql.org
Backpatch-through: 13
ca307d5cec made CheckPointReplicationSlots() unconditionally call
ReplicationSlotsComputeRequiredLSN(). It causes an assertion trap when
max_replication_slots equals 0. This commit makes
CheckPointReplicationSlots() call ReplicationSlotsComputeRequiredLSN() only
when at least one slot gets its last_saved_restart_lsn updated. That avoids
an assert trap and also saves some cycles when no one slot has
last_saved_restart_lsn updated.
Based on ideas from Dilip Kumar <dilipbalaut@gmail.com> and
Hayato Kuroda <kuroda.hayato@fujitsu.com>.
Reported-by: Zhijie Hou <houzj.fnst@fujitsu.com>
Discussion: https://postgr.es/m/OS0PR01MB5716BB506AF934376FF3A8BB947BA%40OS0PR01MB5716.jpnprd01.prod.outlook.com
Commit 7d6d2c4bbd dropped opcintype from the index AM strategy
translation API. But some error messages about failed lookups still
mentioned it, even though it was not used for the lookup. Fix by
removing ipcintype from the error messages as well.
8e03eb92e9 reverted the commit 39b66a91bd which allowed freezing
in the heap_insert() code path but forgot to remove the corresponding
check in heap_xlog_insert(). This code is extraneous but not harmful.
However, cleaning it up makes it very clear that, as of now, we do not
support any freezing of pages in the heap_insert() path.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/flat/CAAKRu_Zp4Pi-t51OFWm1YZ-cctDfBhHCMZ%3DEx6PKxv0o8y2GvA%40mail.gmail.com
Backpatch-through: 14
We can simplify the VM counters added in dc6acfd910 to
lazy_vacuum_heap_page() and lazy_scan_new_or_empty().
We won't invoke lazy_vacuum_heap_page() unless there are dead line
pointers, so we know the page can't be all-visible.
In lazy_scan_new_or_empty(), we only update the VM if the page-level
hint PD_ALL_VISIBLE is clear, and the VM bit cannot be set if the page
level bit is clear because a subsequent page update would fail to clear
the visibility map bit.
Simplify the logic for determining which log counters to increment based
on this knowledge. Doing so is worthwhile because the old logic was
confusing and misguided.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/flat/CAAKRu_a9w_n2mwY%3DG4LjfWTvRTJtjbfvnYAKi4WjO8QXHHrA0g%40mail.gmail.com
Commit 14e87ffa5c introduced support for adding comments to NOT NULL
constraints. However, CREATE TABLE LIKE INCLUDING COMMENTS did not copy
these comments to the new table. This was an oversight in that commit.
This commit corrects the behavior by ensuring CREATE TABLE LIKE to also copy
the comments on NOT NULL constraints when INCLUDING COMMENTS is specified.
Author: Jian He <jian.universality@gmail.com>
Co-authored-by: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/127debef-e558-4784-9e24-0d5eaf91e2d1@oss.nttdata.com
For the subcommand ALTER COLUMN TYPE of the ALTER TABLE command, the
USING expression may reference virtual generated columns. These
columns must be expanded before the expression is fed through
expression_planner and the expression-execution machinery. Failing to
do so can result in incorrect rewrite decisions, and can also lead to
"ERROR: unexpected virtual generated column reference".
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://postgr.es/m/b5f96b24-ccac-47fd-9e20-14681b894f36@gmail.com
Just like selecting from a view is exploitable (CVE-2024-7348),
selecting from a table with virtual generated columns is exploitable.
Users who are concerned about this can avoid selecting from views, but
telling them to avoid selecting from tables is less practical.
To address this, this changes it so that generation expressions for
virtual generated columns are restricted to using built-in functions
and types, and the columns are restricted to having a built-in type.
We assume that built-in functions and types cannot be exploited for
this purpose.
In the future, this could be expanded by some new mechanism to declare
other functions and types as safe or trusted for this purpose, but
that is to be designed.
(An alternative approach might have been to expand the
restrict_nonsystem_relation_kind GUC to handle this, like the fix for
CVE-2024-7348. But that is kind of an ugly approach. That fix had to
fit in the constraints of fixing an ancient vulnerability in all
branches. Since virtual generated columns are new, we're free from
the constraints of the past, and we can and should use cleaner
options.)
Reported-by: Feike Steenbergen <feikesteenbergen@gmail.com>
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAK_s-G2Q7de8Q0qOYUR%3D_CTB5FzzVBm5iZjOp%2BmeVWpMpmfO0w%40mail.gmail.com
This fixes two issues with the handling of VacuumParams in vacuum_rel().
This code path has the idea to change the passed-in pointer of
VacuumParams for the "truncate" and "index_cleanup" options for the
relation worked on, impacting the two following scenarios where
incorrect options may be used because a VacuumParams pointer is shared
across multiple relations:
- Multiple relations in a single VACUUM command.
- TOAST relations vacuumed with their main relation.
The problem is avoided by providing to the two callers of vacuum_rel()
copies of VacuumParams, before the pointer is updated for the "truncate"
and "index_cleanup" options.
The refactoring of the VACUUM option and parameters done in 0d83138974
did not introduce an issue, but it has encouraged the problem we are
dealing with in this commit, with b84dbc8eb8 for "truncate" and
a96c41feec for "index_cleanup" that have been added a couple of years
after the initial refactoring. HEAD will be improved with a different
patch that hardens the uses of VacuumParams across the tree. This
cannot be backpatched as it introduces an ABI breakage.
The backend portion of the patch has been authored by Nathan, while I
have implemented the tests. The tests rely on injection points to check
the option values, making them faster, more reliable than the tests
originally proposed by Shihao, and they also provide more coverage.
This part can only be backpatched down to v17.
Reported-by: Shihao Zhong <zhong950419@gmail.com>
Author: Nathan Bossart <nathandbossart@gmail.com>
Co-authored-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAGRkXqTo+aK=GTy5pSc-9cy8H2F2TJvcrZ-zXEiNJj93np1UUw@mail.gmail.com
Backpatch-through: 13
The logical replication launcher process would sometimes sleep
for as much as 3 minutes before noticing that it is supposed
to launch a new worker. This could happen if
(1) WaitForReplicationWorkerAttach absorbed a process latch wakeup
that was meant to cause ApplyLauncherMain to do work, or
(2) logicalrep_worker_launch reported failure, either because of
resource limits or because the new worker terminated immediately.
In case (2), the expected behavior is that we retry the launch after
wal_retrieve_retry_interval, but that didn't reliably happen.
It's not clear how often such conditions would occur in the field,
but in our subscription test suite they are somewhat common,
especially in tests that exercise cases that cause quick worker
failure. That causes the tests to take substantially longer than
they ought to do on typical setups.
To fix (1), make WaitForReplicationWorkerAttach re-set the latch
before returning if it cleared it while looping. To fix (2), ensure
that we reduce wait_time to no more than wal_retrieve_retry_interval
when logicalrep_worker_launch reports failure. In passing, fix a
couple of perhaps-hypothetical race conditions, e.g. examining
worker->in_use without a lock.
Backpatch to v16. Problem (2) didn't exist before commit 5a3a95385
because the previous code always set wait_time to
wal_retrieve_retry_interval when launching a worker, regardless of
success or failure of the launch. That behavior also greatly
mitigated problem (1), so I'm not excited about adapting the remainder
of the patch to the substantially-different code in older branches.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: https://postgr.es/m/817604.1750723007@sss.pgh.pa.us
Backpatch-through: 16
Commit 62d712ecfd made query jumbling squash lists of Consts as a
single element, but there's no reason not to treat PARAM_EXTERN
parameters the same. For these purposes, these values are indeed
constants for any particular execution of a query.
In particular, this should make list squashing more useful for
applications using extended query protocol, which would use parameters
extensively.
A complication arises: if a query has both external parameters and
squashable lists, then the parameter number used as placeholder for the
squashed list might be inconsistent with regards to the parameter
numbers used by the query literal. To reduce the surprise factor, all
parameters are renumbered starting from 1 in that case.
Author: Sami Imseih <samimseih@gmail.com>
Author: Dmitry Dolgov <9erthalion6@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAA5RZ0tRXoPG2y6bMgBCWNDt0Tn=unRerbzYM=oW0syi1=C1OA@mail.gmail.com
There's no principled reason for query jumbling to only remove the first
layer of RelabelType and CoerceViaIO. Change it to see through as many
layers as there are.
ca307d5cec introduced keeping WAL segments by slot's last saved restart LSN.
It also added an assertion that the slot's restart LSN never goes backward.
However, situations when the restart LSN goes backward have been spotted by
buildfarm animals and investigated in the thread.
When pg_receivewal starts the replication, it sets the last replayed LSN to
the beginning of the segment, which is older than what
ReplicationSlotReserveWal() set for the slot. A similar situation can happen
to pg_basebackup. When standby reconnects to the primary, it sends the last
replayed LSN, which might be older than the last confirmed flush LSN. In
both these situations, a concurrent checkpoint may trigger an assert trap.
Based on ideas from Vitaly Davydov <v.davydov@postgrespro.ru>,
Hayato Kuroda (Fujitsu) <kuroda.hayato@fujitsu.com>,
Vignesh C <vignesh21@gmail.com>,
Amit Kapila <amit.kapila16@gmail.com>.
Reported-by: Vignesh C <vignesh21@gmail.com>
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CALDaNm3s-jpQTe1MshsvQ8GO%3DTLj233JCdkQ7uZ6pwqRVpxAdw%40mail.gmail.com
Reviewed-by: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Specify whether the bucket bounds are inclusive or exclusive,
and improve some other vague language. Explain the behavior that
occurs when the "low" bound is greater than the "high" bound.
Make width_bucket_numeric's comment more like that for
width_bucket_float8, in particular noting that infinite
bounds are rejected (since they became possible in v14).
Reported-by: Ben Peachey Higdon <bpeacheyhigdon@gmail.com>
Author: Robert Treat <rob@xzilla.net>
Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Discussion: https://postgr.es/m/2BD74F86-5B89-4AC1-8F13-23CED3546AC1@gmail.com
Backpatch-through: 13
Commit 85e5e222b, which added (a forerunner of) this logic,
argued that
Adding the necessary complexity to make this work doesn't seem like
it would be repaid in significantly better plans, because in cases
where such a PHV exists, there is probably a corresponding join order
constraint that would allow a good plan to be found without using the
star-schema exception.
The flaw in this claim is that there may be other join-order
restrictions that prevent us from finding a join order that doesn't
involve a "dangerous" PHV. In particular we now recognize that
small join_collapse_limit or from_collapse_limit could prevent it.
Therefore, let's bite the bullet and make the case work.
We don't have to extend the executor's support for nestloop parameters
as I thought at the time, because we can instead push the evaluation
of the placeholder's expression into the left-hand input of the
NestLoop node. So there's not really a lot of downside to this
solution, and giving the planner more join-order flexibility should
have value beyond just avoiding failure.
Having said that, there surely is a nonzero risk of introducing
new bugs. Since this failure mode escaped detection for ten years,
such cases don't seem common enough to justify a lot of risk.
Therefore, let's put this fix into master but leave the back branches
alone (for now anyway).
Bug: #18953
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Diagnosed-by: Richard Guo <guofenglinux@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18953-1c9883a9d4afeb30@postgresql.org
While choosing an autogenerated name for an index, look for
pre-existing relations using a SnapshotDirty snapshot, instead of the
previous behavior that considered only committed-good pg_class rows.
This allows us to detect and avoid conflicts against indexes that are
still being built.
It's still possible to fail due to a race condition, but the window
is now just the amount of time that it takes DefineIndex to validate
all its parameters, call smgrcreate(), and enter the index's pg_class
row. Formerly the race window covered the entire time needed to
create and fill an index, which could be very long if the table is
large. Worse, if the conflicting index creation is part of a larger
transaction, it wouldn't be visible till COMMIT.
So this isn't a complete solution, but it should greatly ameliorate
the problem, and the patch is simple enough to be back-patchable.
It might at some point be useful to do the same for pg_constraint
entries (cf. ChooseConstraintName, ConstraintNameExists, and related
functions). However, in the absence of field complaints, I'll leave
that alone for now. The relation-name test should be good enough for
index-based constraints, while foreign-key constraints seem to be okay
since they require exclusive locks to create.
Bug: #18959
Reported-by: Maximilian Chrzan <maximilian.chrzan@here.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Discussion: https://postgr.es/m/18959-f63b53b864bb1417@postgresql.org
Backpatch-through: 13
Improve the clarity of LOG messages when a failover logical slot
synchronization fails, making the reasons more explicit for easier
debugging.
Update the documentation to outline scenarios where slot synchronization
can fail, especially during the initial sync, and emphasize that
pg_sync_replication_slot() is primarily intended for testing and
debugging purposes.
We also discussed improving the functionality of
pg_sync_replication_slot() so that it can be used reliably, but we would
take up that work for next version after some more discussion and review.
Reported-by: Suraj Kharage <suraj.kharage@enterprisedb.com>
Author: shveta malik <shveta.malik@gmail.com>
Reviewed-by: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 17, where it was introduced
Discussion: https://postgr.es/m/CAF1DzPWTcg+m+x+oVVB=y4q9=PYYsL_mujVp7uJr-_oUtWNGbA@mail.gmail.com
Commit 8492feb98f added support for parallel CREATE INDEX on GIN indexes.
However, previously two places in the documentation and two in the source
code comments still stated that only B-tree and BRIN indexes support
parallel builds.
This commit updates those references to correctly include GIN indexes.
Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Robert Treat <rob@xzilla.net>
Discussion: https://postgr.es/m/7d27d068-90e2-4022-9bd7-09b0fd3d4f47@oss.nttdata.com
This parameter has been introduced in 325f2ec555, and it was not
documented contrary to all the other arguments of
heap_create_with_catalog().
Reviewed-by: Yugo Nagata <nagata@sraoss.co.jp>
Reviewed-by: Steven Niu <niushiji@gmail.com>
Discussion: https://postgr.es/m/aE--bmEv-gJUTH5v@paquier.xyz
Commit 4909b38af0 introduced logic to distribute invalidation messages
from catalog-modifying transactions to all concurrent in-progress
transactions. However, since each transaction distributes not only its
original invalidation messages but also previously distributed
messages to other transactions, this leads to an exponential increase
in allocation request size for invalidation messages, ultimately
causing memory allocation failure.
This commit fixes this issue by tracking distributed invalidation
messages separately per decoded transaction and not redistributing
these messages to other in-progress transactions. The maximum size of
distributed invalidation messages that one transaction can store is
limited to MAX_DISTR_INVAL_MSG_PER_TXN (8MB). Once the size of the
distributed invalidation messages exceeds this threshold, we
invalidate all caches in locations where distributed invalidation
messages need to be executed.
Back-patch to all supported versions where we introduced the fix by
commit 4909b38af0.
Note that this commit adds two new fields to ReorderBufferTXN to store
the distributed transactions. This change breaks ABI compatibility in
back branches, affecting third-party extensions that depend on the
size of the ReorderBufferTXN struct, though this scenario seems
unlikely.
Additionally, it adds a new flag to the txn_flags field of
ReorderBufferTXN to indicate distributed invalidation message
overflow. This should not affect existing implementations, as it is
unlikely that third-party extensions use unused bits in the txn_flags
field.
Bug: #18938#18942
Author: vignesh C <vignesh21@gmail.com>
Reported-by: Duncan Sands <duncan.sands@deepbluecap.com>
Reported-by: John Hutchins <john.hutchins@wicourts.gov>
Reported-by: Laurence Parry <greenreaper@hotmail.com>
Reported-by: Max Madden <maxmmadden@gmail.com>
Reported-by: Braulio Fdo Gonzalez <brauliofg@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Discussion: https://postgr.es/m/680bdaf6-f7d1-4536-b580-05c2760c67c6@deepbluecap.com
Discussion: https://postgr.es/m/18942-0ab1e5ae156613ad@postgresql.org
Discussion: https://postgr.es/m/18938-57c9a1c463b68ce0@postgresql.org
Discussion: https://postgr.es/m/CAD1FGCT2sYrP_70RTuo56QTizyc+J3wJdtn2gtO3VttQFpdMZg@mail.gmail.com
Discussion: https://postgr.es/m/CANO2=B=2BT1hSYCE=nuuTnVTnjidMg0+-FfnRnqM6kd23qoygg@mail.gmail.com
Backpatch-through: 13
Sometimes the TupleDesc used in verify_compact_attribute() is shared
among backends, and since CompactAttribute.attcacheoff gets updated
during tuple deformation, it was possible that another backend would
set attcacheoff on a given CompactAttribute in the small window of time
from when the attcacheoff from the live CompactAttribute was being set
in the 'tmp' CompactAttribute and before the Assert verifying that the
live and tmp CompactAttributes matched.
Here we adjust the code to make a copy of the live CompactAttribute so
that we're not trying to Assert against a shared copy of it.
Author: David Rowley <dgrowleyml@gmail.com>
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/7195e408-758c-4031-8e61-4f842c716ac0@gmail.com
Previously there was no memory barrier enforcing correct memory ordering when
waiting for a free IO handle. However, in the much more common case of waiting
for IO to complete, memory barriers already were present.
On strongly ordered architectures like x86 this had no negative consequences,
but on some armv8 hardware (observed on Apple hardware), it was possible for
the update, in the IO worker, to PgAioHandle->state to become visible before
->distilled_result becoming visible, leading to rather confusing assertion
failures. The failures were rare enough that the bug sometimes took days to
reproduce when running 027_stream_regress in a loop.
Once finally debugged, it was easy enough to come up with a much quicker
repro: Trigger a lot of very fast IO by limiting io_combine_limit to 1 and
ensure that we always have to wait for a free handle by setting
io_max_concurrency to 1. Triggering lots of concurrent seqscans in that setup
triggers the issue within seconds.
One reason this was hard to debug was that the assertion failure most commonly
happened in WaitReadBuffers(), rather than in the AIO subsystem itself. The
assertions added in this commit make problems like this easier to understand.
Also add a comment to the IO worker explaining that we rely on the lwlock
acquisition for correct memory ordering.
I think it'd be good to add a tap test that stress tests buffer IO, but that's
material for a separate patch.
Thanks a lot to Alexander and Konstantin for all the debugging help.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Investigated-by: Andres Freund <andres@anarazel.de>
Investigated-by: Alexander Lakhin <exclusion@gmail.com>
Investigated-by: Konstantin Knizhnik <knizhnik@garret.ru>
Discussion: https://postgr.es/m/2dkz7azclpeiqcmouamdixyn5xhlzy4rvikxrbovyzvi6rnv5c@pz7o7osv2ahf
Our maintenance of typedefs.list has been a little haphazard
(and apparently we can't alphabetize worth a darn). Replace
the file with the authoritative list from our buildfarm, and
run pgindent using that.
I also updated the additions/exclusions lists in pgindent where
necessary to keep pgindent from messing things up significantly.
Notably, now that regex_t and some related names are macros not real
typedefs, we have to whitelist them explicitly. The exclusions list
has also drifted noticeably, presumably due to changes of system
headers on the buildfarm animals that contribute to the list.
Unlike in prior years, I've not manually added typedef names that
are missing from the buildfarm's list because they are not used to
declare any variables or fields. So there are a few places where
the typedef declaration itself is formatted worse than before,
e.g. typedef enum IoMethod. I could preserve the names that were
manually added to the list previously, but I'd really prefer to find
a less manual way of dealing with these cases. A quick grep finds
about 75 such symbols, most of which have never gotten any special
treatment.
Per discussion among pgsql-release, doing this now seems appropriate
even though we're still a week or two away from making the v18 branch.
The new tests verify that logical and physical replication slots are still
valid after an immediate restart on checkpoint completion when the slot was
advanced during the checkpoint.
This commit introduces two new injection points to make these tests possible:
* checkpoint-before-old-wal-removal - triggered in the checkpointer process
just before old WAL segments cleanup;
* logical-replication-slot-advance-segment - triggered in
LogicalConfirmReceivedLocation() when restart_lsn was changed enough to
point to the next WAL segment.
Discussion: https://postgr.es/m/flat/1d12d2-67235980-35-19a406a0%4063439497
Author: Vitaly Davydov <v.davydov@postgrespro.ru>
Author: Tomas Vondra <tomas@vondra.me>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 17
The patch fixes the issue with the unexpected removal of old WAL segments
after checkpoint, followed by an immediate restart. The issue occurs when
a slot is advanced after the start of the checkpoint and before old WAL
segments are removed at the end of the checkpoint.
The patch introduces a new in-memory state for slots: last_saved_restart_lsn,
which is used to calculate the oldest LSN for removing WAL segments. This
state is updated every time with the current restart_lsn at the moment when
the slot is saved to disk.
This fix changes the shared memory layout. It's applied to HEAD only because
we don't have to preserve ABI compatibility during the beta stage. Another
fix that doesn't affect the ABI is committed to back branches.
Discussion: https://postgr.es/m/1d12d2-67235980-35-19a406a0%4063439497
Author: Vitaly Davydov <v.davydov@postgrespro.ru>
Author: Alexander Korotkov <aekorotkov@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
_bt_readnextpage expects so->currPos.buf to be InvalidBuffer (and for
the position's page to be unlocked) when called. However, it does not
expect there to be no pins held on any page. In particular, so->markPos
might hold a separate pin, both before and after the call. Fix some
comments that seemed to suggest otherwise.
Follow-up commit to commit 7c319f54, which made _bt_killitems drop pins
it acquired itself.
This is a continuation of 15a79c7311, cleaning up the AIO io_uring
code that has been committed after that while still using %llu.
The code changed here is new in v18, so cleaning things now means less
conflicts if this area of the code changes on backpatch once the 18
stable branch is created.
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/aEZcGCnYFq642q8k@paquier.xyz
The algorithm to squash lists of constants added by commit 62d712ecfd
was a bit too simplistic; we wanted to avoid adding unnecessary
complexity, but cases like direct function calls of typecasting
functions (and others) were missed, and bogus SQL syntax was being shown
in pg_stat_statements normalized query text field. To fix normalization
for those cases, we need the parser to transmit information about were
each list of constant values starts and ends, so add that to a couple of
nodes. Also add a few more test cases to make sure we're doing the
right thing.
The patch initially submitted by Sami added a new private struct in
gram.y to carry the start/end information for A_Expr, but I (Álvaro)
decided that a better fix was to remove the parser indirection via the
in_expr production, and instead create separate components in the a_expr
rule. I'm surprised that this works and doesn't require more changes,
but I assume (without checking) that the grammar used to be more complex
and got simplified at some point.
Bump catversion.
Author: Sami Imseih <samimseih@gmail.com>
Author: Dmitry Dolgov <9erthalion6@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAA5RZ0tRXoPG2y6bMgBCWNDt0Tn=unRerbzYM=oW0syi1=C1OA@mail.gmail.com
This commit reverts the two following commits:
- 499edb0974, track more precisely query locations for nested
statements.
- 06450c7b8c, a follow-up fix of 499edb0974 with query locations.
The test introduced in this commit is not reverted. This is proving
useful to track a problem that only pgaudit was able to detect.
These prove to have issues with the tracking of SELECT statements, when
these use multiple parenthesis which is something supported by the
grammar. Incorrect location and lengths are causing pg_stat_statements
to become confused, failing its job in query normalization with
potential out-of-bound writes because the location and the length may
not match with what can be handled. A lot of the query patterns
discussed when this issue was reported have no test coverage in the main
regression test suite, or the recovery test 027_stream_regress.pl would
have caught the problems as pg_stat_statements is loaded by the node
running the regression tests. A first step would be to improve the test
coverage to stress more the query normalization logic.
A different portion of this work was done in 45e0ba30fc, with the
addition of tests for nested queries. These can be left in the tree.
They are useful to track the way inner queries are currently tracked by
PGSS with non-top-level entries, and will be useful when reconsidering
in the future the work reverted here.
Reported-by: Alexander Kozhemyakin <a.kozhemyakin@postgrespro.ru>
Discussion: https://postgr.es/m/18947-cdd2668beffe02bf@postgresql.org
Teach nbtree's _bt_killitems to leave the so->currPos page that it sets
LP_DEAD items on in whatever state it was in when _bt_killitems was
called. In particular, make sure that so->dropPin scans don't acquire a
pin whose reference is saved in so->currPos.buf.
Allowing _bt_killitems to change so->currPos.buf like this is wrong.
The immediate consequence of allowing it is that code in _bt_steppage
(that copies so->currPos into so->markPos) will behave as if the scan is
a !so->dropPin scan. so->markPos will therefore retain the buffer pin
indefinitely, even though _bt_killitems only needs to acquire a pin
(along with a lock) for long enough to mark known-dead items LP_DEAD.
This issue came to light following a report of a failure of an assertion
from recent commit e6eed40e. The test case in question involves the use
of mark and restore. An initial call to _bt_killitems takes place that
leaves so->currPos.buf in a state that is inconsistent with the scan
being so->dropPin. A subsequent call to _bt_killitems for the same
position (following so->currPos being saved in so->markPos, and then
restored as so->currPos) resulted in the failure of an assertion that
tests that so->currPos.buf is InvalidBuffer when the scan is so->dropPin
(non-assert builds got a "resource was not closed" WARNING instead).
The same problem exists on earlier releases, though the issue is far
more subtle there. Recent commit e6eed40e introduced the so->dropPin
field as a partial replacement for testing so->currPos.buf directly.
Earlier releases won't get an assertion failure (or buffer pin leak),
but they will allow the second _bt_killitems call from the test case to
behave as if a buffer pin was consistently held since the original call
to _bt_readpage. This is wrong; there will have been an initial window
during which no pin was held on the so->currPos page, and yet the second
_bt_killitems call will neglect to check if so->currPos.lsn continues to
match the page's now-current LSN.
As a result of all this, it's just about possible that _bt_killitems
will set the wrong items LP_DEAD (on release branches). This could only
happen with merge joins (the sole user of nbtree mark/restore support),
when a concurrently inserted index tuple used a recently-recycled TID
(and only when the new tuple was inserted onto the same page as a
distinct concurrently-removed tuple with the same TID). This is exactly
the scenario that _bt_killitems' check of the page's now-current LSN
against the LSN stashed in currPos was supposed to prevent.
A follow-up commit will make nbtree completely stop conditioning whether
or not a position's pin needs to be dropped on whether the 'buf' field
is set. All call sites that might need to drop a still-held pin will be
taught to rely on the scan-level so->dropPin field recently introduced
by commit e6eed40e. That will make bugs of the same general nature as
this one impossible (or make them much easier to detect, at least).
Author: Peter Geoghegan <pg@bowt.ie>
Reported-By: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/545be1e5-3786-439a-9257-a90d30f8b849@gmail.com
Backpatch-through: 13
Traditionally, libpq's pqPutMsgEnd has rounded down the amount-to-send
to be a multiple of 8K when it is eagerly writing some data. This
still seems like a good idea when sending through a Unix socket, as
pipes typically have a buffer size of 8K or some fraction/multiple of
that. But there's not much argument for it on a TCP connection, since
(a) standard MTU values are not commensurate with that, and (b) the
kernel typically applies its own packet splitting/merging logic.
Worse, our SSL and GSSAPI code paths both have API stipulations that
if they fail to send all the data that was offered in the previous
write attempt, we mustn't offer less data in the next attempt; else
we may get "SSL error: bad length" or "GSSAPI caller failed to
retransmit all data needing to be retried". The previous write
attempt might've been pqFlush attempting to send everything in the
buffer, so pqPutMsgEnd can't safely write less than the full buffer
contents. (Well, we could add some more state to track exactly how
much the previous write attempt was, but there's little value evident
in such extra complication.) Hence, apply the round-down only on
AF_UNIX sockets, where we never use SSL or GSSAPI.
Interestingly, we had a very closely related bug report before,
which I attempted to fix in commit d053a879b. But the test case
we had then seemingly didn't trigger this pqFlush-then-pqPutMsgEnd
scenario, or at least we failed to recognize this variant of the bug.
Bug: #18907
Reported-by: Dorjpalam Batbaatar <htgn.dbat.95@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18907-d41b9bcf6f29edda@postgresql.org
Backpatch-through: 13
We concluded that commit e5a3c9d9b is a feature rather than a fix; since
it was added after feature freeze, revert it.
Reported-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reported-by: Michael Paquier <michael@paquier.xyz>
Reported-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/ed2296f1-1a6b-4932-b870-5bb18c2591ae%40oss.nttdata.com
Commit 5fe08c006c fixed this for calls to dshash_create(). This
commit fixes calls to dshash_attach() and dsa_create_in_place().
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/aECi_gSD9JnVWQ8T%40nathan
Delay calling BufferGetLSNAtomic() until we finish reading a page that
actually contains items that btgettuple will return to the executor.
This reduces the number of calls during plain index scans (we'll only
call BufferGetLSNAtomic() when _bt_readpage returns true), and totally
eliminates calls during index-only scans, bitmap index scans, and plain
index scans of an unlogged relation.
Currently, when checksums (or wal_log_hints) are enabled, acquiring a
page's LSN in BufferGetLSNAtomic() involves locking the buffer header
(which involves the use of spinlocks). Testing has shown that enabling
page-level checksums causes large regressions with certain workloads,
especially on larger multi-socket systems.
The regression isn't tied to any Postgres 18 commit. However, Postgres
18 commit 04bec894 made initdb use checksums by default, so it seems
prudent to address the problem now.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/941f0190-e3c6-4622-9ac7-c04e936e5fdb@vondra.me
Discussion: https://postgr.es/m/CAH2-Wzk-Dg5XWs_jDuiHt4_7ryrSY+n=vxmHY51EVqPDFsKXmg@mail.gmail.com
Use of a RowCompare key makes nbtree index scans ineligible to use
pstate.forcenonrequired following recent bugfix commit 5f4d98d4.
There's no longer any need for _bt_check_rowcompare to accept a
forcenonrequired argument, so remove it.
Similar to commit cc733ed164: when an unenforced foreign key that
references a partitioned table is altered to be enforced, we scan
the constrained table based on each partition on the referenced
partitioned table. This is bogus and likely to cause the ALTER TABLE to
fail: we must only scan the constrained table as pointing to the
top-level partitioned table. Oversight in commit eec0040c4b. Fix by
eliding those scans.
Author: Amul Sul <sulamul@gmail.com>
Reported-by: jian he <jian.universality@gmail.com>
Discussion: https://postgr.es/m/CACJufxF1e_gPOLtsDoaE4VCgQPC8KZW_kPAjPR5Rvv4Ew=fb2A@mail.gmail.com
Validating an unvalidated foreign key that references a partitioned
table would try to queue validations for each individual partition of
the referenced table, but this is wrong: each individual partition would
not necessarily have all the referenced rows, so errors would be raised.
Avoid doing that. The pg_constraint rows that cause this to happen are
only there to support the action triggers that implement the DELETE/
UPDATE actions of the FK, so no validating scan is necessary.
This was an oversight in commit b663b9436e.
An equivalent oversight exists for NOT ENFORCED constraints, which is
not fixed in this commit.
Author: Amul Sul <sulamul@gmail.com>
Reported-by: Antonin Houska <ah@cybertec.at>
Reviewed-by: jian he <jian.universality@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Discussion: https://postgr.es/m/26983.1748418675@localhost
This commit replaces the formula used for "TotalProcs" with a call to
pgaio_uring_procs() in pgaio_uring_shmem_init() for the shared memory
initialization, which is exactly the same, removing a duplication.
pgaio_uring_procs() is used for shared memory sizing and a sanity check,
and it has some documentation explaining some reasoning behind the
formula.
Author: Japin Li <japinli@hotmail.com>
Discussion: https://postgr.es/m/ME0P300MB044521067A1EDDA9EDEC3793B66DA@ME0P300MB0445.AUSP300.PROD.OUTLOOK.COM
Commit 4f7f7b0375 implemented the extension_control_path GUC, and to
make it work it was decided that we should strip the $libdir/ on
module_pathname from .control files, so that extensions don't need to
worry about this change.
This strip logic was implemented on expand_dynamic_library_name()
which works fine when executing the SQL functions from extensions, but
this function is also called when the LOAD command is executed, and
since the user may explicitly pass the $libdir prefix on LOAD
parameter, we should not strip in this case.
This commit fixes this issue by moving the strip logic from
expand_dynamic_library_name() to load_external_function() that is
called when the running the SQL script from extensions.
Reported-by: Evan Si <evsi@amazon.com>
Author: Matheus Alcantara <matheusssilv97@gmail.com>
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Rahila Syed <rahilasyed90@gmail.com>
Bug: #18920
Discussion: https://www.postgresql.org/message-id/flat/18920-b350b1c0a30af006%40postgresql.org
This commit renames the GUC log_lock_failure to log_lock_failures
to align with the existing similar setting log_lock_waits, which uses
the plural form. This improves naming consistency across related GUCs.
Suggested-by: Peter Eisentraut <peter@eisentraut.org>
Author: Fujii Masao <masao.fujii@gmail.com
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/7a8198b6-d5b8-4910-b41e-8d3efcbb015d@eisentraut.org
We store values for these options as array elements with the syntax
"name=value", hence a name containing "=" confuses matters when
it's time to read the array back in. Since validation of the
options is often done (long) after this conversion to array format,
that leads to confusing and off-point error messages. We can
improve matters by rejecting names containing "=" up-front.
(Probably a better design would have involved pairs of array
elements, but it's too late now --- and anyway, there's no
evident use-case for option names like this. We already
reject such names in some other contexts such as GUCs.)
Reported-by: Chapman Flack <jcflack@acm.org>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Chapman Flack <jcflack@acm.org>
Discussion: https://postgr.es/m/6830EB30.8090904@acm.org
Backpatch-through: 13
052026c9b9 mistakenly reordered setup steps in heap_vacuum_rel(),
incorrectly moving RelationGetNumberOfBlocks() before
vacuum_get_cutoffs().
OldestXmin must be determined before RelationGetNumberOfBlocks()
calculates the number of blocks in the relation that will be vacuumed.
Otherwise tuples older than OldestXmin may be inserted into the end of
the relation into blocks that are not vacuumed. If additional tuples
newer than those inserted into unscanned blocks but older than
OldestXmin are inserted into free space earlier in the relation, the
result could be advancing pg_class.relfrozenxid to a newer value than an
unfrozen XID in one of the unscanned heap pages.
Assigning an incorrect relfrozenxid can lead to data loss, so it is
imperative that it correctly reflect the oldest unfrozen xid.
Reported-by: Peter Geoghegan <pg@bowt.ie>
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-WzntqvVEdbbpqG5JqSZGuLWmy4PBfUO-OswfivKchr2gvw%40mail.gmail.com
Commit 7406ab623f added a gist support function that we internally
refer to by the symbol GIST_STRATNUM_PROC. This translated from
"well-known" strategy numbers to opfamily-specific strategy numbers.
However, we later (commit 630f9a43ce) changed this to fit into
index-AM-level compare type mapping, so this function actually now
maps from compare type to opfamily-specific strategy numbers. So this
name is no longer fitting.
Moreover, the index AM level also supports the opposite, a function to
map from strategy number to compare type. This is currently not
supported in gist, but one might wonder what this function is supposed
to be called when it is added.
This patch changes the naming of the gist-level functionality to be
more in line with the index-AM-level functionality. This makes sense
because these are essentially the same thing on different levels.
This also changes the names of the externally visible functions that
are provided for use as such a support function.
Reviewed-by: Paul A Jungwirth <pj@illuminatedcomputing.com>
Discussion: https://www.postgresql.org/message-id/37ebb1d9-9036-485f-a215-e55435689917%40eisentraut.org
A cascading WAL sender doing logical decoding (as known as doing its
work on a standby) has been using as flush LSN the value returned by
GetStandbyFlushRecPtr() (last position safely flushed to disk). This is
incorrect as such processes are only able to decode changes up to the
LSN that has been replayed by the startup process.
This commit changes cascading logical WAL senders to use the replay LSN,
as returned by GetXLogReplayRecPtr(). This distinction is important
particularly during shutdown, when WAL senders need to send any
remaining available data to their clients, switching WAL senders to a
caught-up state. Using the latest flush LSN rather than the replay LSN
could cause the WAL senders to be stuck in an infinite loop preventing
them to shut down, as the startup process does not run when WAL senders
attempt to catch up, so they could keep waiting for work that would
never happen.
Backpatch down to v16, where logical decoding on standbys has been
introduced.
Author: Alexey Makhmutov <a.makhmutov@postgrespro.ru>
Reviewed-by: Ajin Cherian <itsajin@gmail.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/52138028-7246-421c-9161-4fa108b88070@postgrespro.ru
Backpatch-through: 16
Previously, postgres_fdw always 1) opened a remote transaction in READ
WRITE mode even when the local transaction was READ ONLY, causing a READ
ONLY transaction using it that references a foreign table mapped to a
remote view executing a volatile function to write in the remote side,
and 2) opened the remote transaction in NOT DEFERRABLE mode even when
the local transaction was DEFERRABLE, causing a SERIALIZABLE READ ONLY
DEFERRABLE transaction using it to abort due to a serialization failure
in the remote side.
To avoid these, modify postgres_fdw to open a remote transaction in the
same access/deferrable modes as the local transaction. This commit also
modifies it to open a remote subtransaction in the same access mode as
the local subtransaction.
Although these issues exist since the introduction of postgres_fdw,
there have been no reports from the field. So it seems fine to just fix
them in master only.
Author: Etsuro Fujita <etsuro.fujita@gmail.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAPmGK16n_hcUUWuOdmeUS%2Bw4Q6dZvTEDHb%3DOP%3D5JBzo-M3QmpQ%40mail.gmail.com
When a MERGE's target table is the parent of an inheritance tree, any
INSERT actions insert into the parent table using ModifyTableState's
rootResultRelInfo. However, there are two bugs in the way is
initialized:
1. ExecInitMerge() incorrectly uses a different ResultRelInfo entry
from ModifyTableState's resultRelInfo array to build the insert
projection, which may not be compatible with rootResultRelInfo.
2. ExecInitModifyTable() does not fully initialize rootResultRelInfo.
Specifically, ri_WithCheckOptions, ri_WithCheckOptionExprs,
ri_returningList, and ri_projectReturning are not initialized.
This can lead to crashes, or incorrect query results due to failing to
check WCO's or process the RETURNING list for INSERT actions.
Fix both these bugs in ExecInitMerge(), noting that it is only
necessary to fully initialize rootResultRelInfo if the MERGE has
INSERT actions and the target table is a plain inheritance parent.
Backpatch to v15, where MERGE was introduced.
Reported-by: Andres Freund <andres@anarazel.de>
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
Reviewed-by: Jian He <jian.universality@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Discussion: https://postgr.es/m/4rlmjfniiyffp6b3kv4pfy4jw3pciy6mq72rdgnedsnbsx7qe5@j5hlpiwdguvc
Backpatch-through: 15
uint64 was chosen to be consistent with the type used by the query ID,
but the conclusion of a recent discussion for the query ID is that int64
is a better fit as the signed form is shown to the user, for PGSS or
EXPLAIN outputs.
This commit changes the plan ID to use int64, following c3eda50b06
that has done the same for the query ID.
The plan ID is new to v18, introduced in 2a0cd38da5.
Author: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Discussion: https://postgr.es/m/aCvzJNwetyEI3Sgo@paquier.xyz
A few places that access system catalogs don't set up an active
snapshot before potentially accessing their TOAST tables. To fix,
push an active snapshot just before each section of code that might
require accessing one of these TOAST tables, and pop it shortly
afterwards. While at it, this commit adds some rather strict
assertions in an attempt to prevent such issues in the future.
Commit 16bf24e0e4 recently removed pg_replication_origin's TOAST
table in order to fix the same problem for that catalog. On the
back-branches, those bugs are left in place. We cannot easily
remove a catalog's TOAST table on released major versions, and only
replication origins with extremely long names are affected. Given
the low severity of the issue, fixing older versions doesn't seem
worth the trouble of significantly modifying the patch.
Also, on v13 and v14, the aforementioned strict assertions have
been omitted because commit 2776922201, which added
HaveRegisteredOrActiveSnapshot(), was not back-patched. While we
could probably back-patch it now, I've opted against it because it
seems unlikely that new TOAST snapshot issues will be introduced in
the oldest supported versions.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/18127-fe54b6a667f29658%40postgresql.org
Discussion: https://postgr.es/m/18309-c0bf914950c46692%40postgresql.org
Discussion: https://postgr.es/m/ZvMSUPOqUU-VNADN%40nathan
Backpatch-through: 13
Our GSSAPI code only allows packet sizes up to 16kB. However it
emerges that during authentication, larger packets might be needed;
various authorities suggest 48kB or 64kB as the maximum packet size.
This limitation caused login failure for AD users who belong to many
AD groups. To add insult to injury, we gave an unintelligible error
message, typically "GSSAPI context establishment error: The routine
must be called again to complete its function: Unknown error".
As noted in code comments, the 16kB packet limit is effectively a
protocol constant once we are doing normal data transmission: the
GSSAPI code splits the data stream at those points, and if we change
the limit then we will have cross-version compatibility problems
due to the receiver's buffer being too small in some combinations.
However, during the authentication exchange the packet sizes are
not determined by us, but by the underlying GSSAPI library. So we
might as well just try to send what the library tells us to.
An unpatched recipient will fail on a packet larger than 16kB,
but that's not worse than the sender failing without even trying.
So this doesn't introduce any meaningful compatibility problem.
We still need a buffer size limit, but we can easily make it be
64kB rather than 16kB until transport negotiation is complete.
(Larger values were discussed, but don't seem likely to add
anything.)
Reported-by: Chris Gooch <cgooch@bamfunds.com>
Fix-suggested-by: Jacob Champion <jacob.champion@enterprisedb.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Jacob Champion <jacob.champion@enterprisedb.com>
Discussion: https://postgr.es/m/DS0PR22MB5971A9C8A3F44BCC6293C4DABE99A@DS0PR22MB5971.namprd22.prod.outlook.com
Backpatch-through: 13
Previously, XactLockTableWait() and ConditionalXactLockTableWait() could enter
a non-interruptible loop when they successfully acquired a lock on a transaction
but the transaction still appeared to be running. Since this loop continued
until the transaction completed, it could result in long, uninterruptible waits.
Although this scenario is generally unlikely since XactLockTableWait() and
ConditionalXactLockTableWait() can basically acquire a transaction lock
only when the transaction is not running, it can occur in a hot standby.
In such cases, the transaction may still appear active due to
the KnownAssignedXids list, even while no lock on the transaction exists.
For example, this situation can happen when creating a logical replication
slot on a standby.
The cause of the non-interruptible loop was the absence of CHECK_FOR_INTERRUPTS()
within it. This commit adds CHECK_FOR_INTERRUPTS() to the loop in both functions,
ensuring they can be interrupted safely.
Back-patch to all supported branches.
Author: Kevin K Biju <kevinkbiju@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/CAM45KeELdjhS-rGuvN=ZLJ_asvZACucZ9LZWVzH7bGcD12DDwg@mail.gmail.com
Backpatch-through: 13
uint64 was perhaps chosen in cff440d36 as the type was uint32 prior to
that widening work.
Having this as uint64 doesn't make much sense and just adds the overhead of
having to remember that we always output this in its signed form. Let's
remove that overhead.
The signed form output is seemingly required since we have no way to
represent the full range of uint64 in an SQL type. We use BIGINT in places
like pg_stat_statements, which maps directly to int64.
The release notes "Source Code" section may want to mention this
adjustment as some extensions may wish to adjust their code.
Author: David Rowley <dgrowleyml@gmail.com>
Suggested-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/50cb0c8b-994b-48f9-a1c4-13039eb3536b@eisentraut.org
ParseFraction only expects to deal with fields that contain a decimal
point and digit(s). However it's possible in some edge cases for it
to be passed input that doesn't look like that. In particular the
input could look like a valid floating-point number, such as ".123e6".
strtod() will happily eat that, possibly producing a result that is
not within the expected range 0..1, which can result in integer
overflow in the callers. That doesn't have any security consequences,
but it's still not very desirable. Fix by checking that the input
has the expected form.
Similarly, DecodeNumberField only expects to deal with fields that
contain a decimal point and digit(s), but it's sometimes abused to
parse strings that might not look like that. This could result in
failure to reject bogus input, yielding silly results. Again, fix
by rejecting input that doesn't look as-expected. That decision
also means that we can affirmatively answer the very old comment
questioning whether we couldn't save some duplicative code by
using ParseFractionalSecond here.
While these changes should only reject input that nobody would
consider valid, it still doesn't seem like a change to make in
stable branches. Apply to HEAD only.
Reported-by: Evgeniy Gorbanev <gorbanev.es@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/1328335.1748371099@sss.pgh.pa.us
In pl_comp.c, initially create the plpgsql function's cache context
under the assumed-short-lived caller's context, and reparent it under
CacheMemoryContext only upon success. This avoids a process-lifespan
leak of 8kB or more if the function contains syntax errors. (This
leakage has existed for a long time without many complaints, but as
we move towards a possibly multi-threaded future, getting rid of
process-lifespan leaks grows more important.)
In funccache.c, arrange to reclaim the CachedFunction struct in case
the language-specific compile callback function throws an error;
previously, that resulted in an independent process-lifespan leak.
This is arguably a new bug in v18, since the leakage now occurred
for SQL-language functions as well as plpgsql.
Also, don't fill fn_xmin/fn_tid/dcallback until after successful
completion of the compile callback. This avoids a scenario where a
partially-built function cache might appear already valid upon later
inspection, and another scenario where dcallback might fail upon being
presented with an incomplete cache entry. We would have to reach such
a faulty cache entry via a pre-existing fn_extra pointer, so I'm not
sure these scenarios correspond to any live bug. (The predecessor
code in pl_comp.c never took any care about this, and we've heard no
complaints about that.) Still, it's better to be careful.
Given the lack of field complaints, I'm not very excited about
back-patching any of this; but it seems still in-scope for v18.
Discussion: https://postgr.es/m/999171.1748300004@sss.pgh.pa.us
The code that translates SIMILAR TO pattern matching expressions to
POSIX-style regular expressions did not consider that square brackets
can be nested. For example, in an expression like [[:alpha:]%_], the
logic replaced the placeholders '_' and '%' but it should not.
This commit fixes the conversion logic by tracking the nesting level of
square brackets marking character class areas, while considering that
in expressions like []] or [^]] the first closing square bracket is a
regular character. Multiple tests are added to show how the conversions
should or should not apply applied while in a character class area, with
specific cases added for all the characters converted outside character
classes like an opening parenthesis '(', dollar sign '$', etc.
Author: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/16ab039d1af455652bdf4173402ddda145f2c73b.camel@cybertec.at
Backpatch-through: 13
Previously, we asserted that the eager scan's success and failure
counters were positive before decrementing them. However, this
assumption was incorrect, as it's possible that some blocks have
already been eagerly scanned by the time eager scanning is disabled.
This commit replaces the assertions with guards to handle this
scenario gracefully.
With this change, we continue to allow read-ahead operations by the
read stream that exceed the success and failure caps. While there is a
possibility that overruns will trigger eager scans of additional
pages, this does not pose a practical concern as the overruns will not
be substantial and remain within an acceptable range.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAD21AoConf6tkVCv-=JhQJj56kYsDwo4jG5+WqgT+ukSkYomSQ@mail.gmail.com
PgStat_StatTabEntry and AutoVacOpts structs were leaked until
the end of the autovacuum worker's run, which is bad news if
there are a lot of relations in the database.
Note: pfree'ing the PgStat_StatTabEntry structs here seems a bit
risky, because pgstat_fetch_stat_tabentry_ext does not guarantee
anything about whether its result is long-lived. It appears okay
so long as autovacuum forces PGSTAT_FETCH_CONSISTENCY_NONE, but
I think that API could use a re-think.
Also ensure that the VacuumRelation structure passed to
vacuum() is in recoverable storage.
Back-patch to v15 where we started to manage table statistics
this way. (The AutoVacOpts leakage is probably older, but
I'm not excited enough to worry about just that part.)
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/285483.1746756246@sss.pgh.pa.us
Backpatch-through: 15
If the inner allocation call returns NULL, we should restore the
previous state and return NULL. Previously this code pfree'd
the old chunk anyway, which is surely wrong.
Also, make it call MemoryContextAllocationFailure rather than
summarily returning NULL. The fact that we got control back from the
inner call proves that MCXT_ALLOC_NO_OOM was passed, so this change
is just cosmetic, but someday it might be less so.
This is just a latent bug at present: AFAICT no in-core callers use
this function at all, let alone call it with MCXT_ALLOC_NO_OOM.
Still, it's the kind of bug that might bite back-patched code pretty
hard someday, so let's back-patch to v17 where the bug was introduced
(by commit 743112a2e).
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/285483.1746756246@sss.pgh.pa.us
Backpatch-through: 17
Move oauth_validator_libraries in postgresql.conf.sample to be grouped
with the other CONN_AUTH_AUTH settings, rather than making up a new
ad-hoc category. This matches the internal categorization and also
how it is listed in the documentation.
9219093cab modularized log_connections output to allow more
granular control over which aspects of connection establishment are
logged. It converted the boolean log_connections GUC into a list of strings
and deprecated previously supported boolean-like values on, off, true,
false, 1, 0, yes, and no. Those values still work, but they are
supported mainly for backwards compatability. As such, documented
examples of log_connections should not use these deprecated values.
Update references in the docs to deprecated log_connections values. Many
of the tests use log_connections. This commit also updates the tests to
use the new values of log_connections. In some of the tests, the updated
log_connections value covers a narrower set of aspects (e.g. the
'authentication' aspect in the tests in src/test/authentication and the
'receipt' aspect in src/test/postmaster). In other cases, the new value
for log_connections is a superset of the previous included aspects (e.g.
'all' in src/test/kerberos/t/001_auth.pl).
Reported-by: Peter Eisentraut <peter@eisentraut.org>
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Jacob Champion <jacob.champion@enterprisedb.com>
Discussion: https://postgr.es/m/e1586594-3b69-4aea-87ce-73a7488cdc97%40eisentraut.org
The code carelessly modified mtstate->ps.plan->targetlist,
which it's not supposed to do. Fortunately, there's not
really any need to do that because the planner already
set up a perfectly acceptable targetlist for the plan node.
We just need to remove the erroneous assignments and update some
relevant comments.
As it happens, the erroneous assignments caused the targetlist to
point to a different part of the source plan tree, so that there
isn't really a risk of the pointer becoming dangling after executor
termination. The only visible effect of this change we can find is
that EXPLAIN will show upper references to the ModifyTable's output
expressions using different variables. Formerly it showed Vars from
the first target relation that survived executor-startup pruning.
Now it always shows such references using the first relation appearing
in the planner output, independently of what happens during executor
pruning. On the whole that seems like a good thing.
Also make a small tweak in ExplainPreScanNode to ensure that the first
relation will receive a refname assignment in set_rtable_names, even
if it got pruned at startup. Previously the Vars might be shown
without any table qualification, which is confusing in a multi-table
query.
I considered back-patching this, but since the bug doesn't seem to
have any really terrible consequences in existing branches, it
seems better to not change their EXPLAIN output. It's not too late
for v18 though, especially since v18 already made other changes in
the EXPLAIN output for these cases.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Author: Andres Freund <andres@anarazel.de>
Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/213261.1747611093@sss.pgh.pa.us
xmltotext_with_options sometimes tries to replace the existing
root node of a libxml2 document. In that case xmlDocSetRootElement
will unlink and return the old root node; if we fail to free it,
it's leaked for the remainder of the session. The amount of memory
at stake is not large, a couple hundred bytes per occurrence, but
that could still become annoying in heavy usage.
Our only other xmlDocSetRootElement call is not at risk because
it's working on a just-created document, but let's modify that
code too to make it clear that it's dependent on that.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Jim Jones <jim.jones@uni-muenster.de>
Discussion: https://postgr.es/m/1358967.1747858817@sss.pgh.pa.us
Backpatch-through: 16
As pointed out by Tom Lane, the patch introduced fragile and invasive
design around plan invalidation handling when locking of prunable
partitions was deferred from plancache.c to the executor. In
particular, it violated assumptions about CachedPlan immutability and
altered executor APIs in ways that are difficult to justify given the
added complexity and overhead.
This also removes the firstResultRels field added to PlannedStmt in
commit 28317de72, which was intended to support deferred locking of
certain ModifyTable result relations.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/605328.1747710381@sss.pgh.pa.us
pg_aios used the terms "read" and "write" for vectored I/O read and
write operations, respectively. The documentation refers to them as
"readv" and "writev", and the code uses internally the terms
PGAIO_OP_READV and PGAIO_OP_WRITEV for them, as of "vectored".
This commit adjusts these operation names to match with the code and the
documentation.
Oversight in 8e293e689b.
Author: Atsushi Torikoshi <torikoshia@oss.nttdata.com>
Discussion: https://postgr.es/m/6df1e949d1d759ad2767c18e5845963e@oss.nttdata.com
Since commit 8b1dccd37c, the PREPARE TRANSACTION WAL record includes
information about dropped statistics entries. However, the WAL resource
manager description function for PREPARE TRANSACTION record failed to
parse this information correctly and always assumed there were
no such entries.
As a result, for example, pg_waldump could not display the dropped
statistics entries stored in PREPARE TRANSACTION records.
The root cause was that ParsePrepareRecord() did not set the number of
statistics entries to drop on commit or abort. These values remained
zero-initialized and were never updated from the parsed record.
This commit fixes the issue by properly setting those values during parsing.
With this fix, pg_waldump can now correctly report dropped statistics
entries in PREPARE TRANSACTION records.
Back-patch to v15, where commit 8b1dccd37c was introduced.
Author: Daniil Davydov <3danissimo@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/CAJDiXgh-6Epb2XiJe4uL0zF-cf0_s_7Lw1TfEHDMLzYjEmfGOw@mail.gmail.com
Backpatch-through: 15
The statement location calculated for some nested query cases was wrong
when multiple queries are sent as a single string, these being separated
by semicolons. As pointed by Sami Imseih, the location calculation was
incorrect when the last query of nested statement with multiple queries
does **NOT** finish with a semicolon for the last statement. In this
case, the statement length tracked by RawStmt is 0, which is equivalent
to say that the string should be used until its end. The code
previously discarded this case entirely, causing the location to remain
at 0, the same as pointing at the beginning of the string. This caused
pg_stat_statements to store incorrect query strings.
This issue has been introduced in 499edb0974. I have looked at the
diffs generated by pgaudit back then, and noticed the difference
generated for this nested query case, but I have missed the point that
it was an actual regression with an existing case. A test case is added
in pg_stat_statements to provide some coverage, restoring the pre-17
behavior for the calculation of the query locations. Special thanks to
David Steele, who, through an analysis of the test diffs generated by
pgaudit with the new v18 logic, has poked me about the fact that my
original analysis of the matter was wrong.
The test output of pg_overexplain is updated to reflect the new logic,
as the new locations refer to the beginning of the argument passed to
the function explain_filter(). When the module was introduced in
8d5ceb113e, which was after 499edb0974 (for the new calculation
method), the locations of the test were not actually right: the plan
generated for the query string given in input of the function pointed to
the top-level query, not the nested one.
Reported-by: David Steele <david@pgbackrest.org>
Author: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com>
Reviewed-by: Jian He <jian.universality@gmail.com>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Reviewed-by: David Steele <david@pgbackrest.org>
Discussion: https://postgr.es/m/844a3b38-bbf1-4fb2-9fd6-f58c35c09917@pgbackrest.org
elog()/ereport() process interrupts, iff the log message is < ERROR and the
log message will be emitted. aio's debug messages are emitted via ereport(),
but in some places the code is not ready for interrupts to be processed.
Fix the issue using a few different methods:
1) handle interrupts arriving concurrently - in some places it's easy to
detect that by fetching the handle's generation a bit earlier
2) Check if interrupts made the work needing to be done obsolete
3) Disallow interrupts, as there's no sane way to make interrupt processing
safe
To prevent some similar issues from being re-introduced, assert that
interrupts are held in pgaio_io_update_state().
This commit also fixes the contents of a debug message I added in 039bfc457e.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/mvpm7ga3dfgz7bvum22hmuz26cariylmcppb3irayftc7bwk3r@l7gb6gr7azhc
In the grammar, <expr> is a c_expr, which accepts only a limited set
of integer literals and simple expressions without parens. The
deparsing logic didn't quite match the grammar rule, and failed to use
parens e.g. for "5::bigint".
To fix, always surround the expression with parens. Would be nice to
omit the parens in simple cases, but unfortunately it's non-trivial to
detect such simple cases. Even if the expression is a simple literal
123 in the original query, after parse analysis it becomes a FuncExpr
with COERCE_IMPLICIT_CAST rather than a simple Const.
Reported-by: yonghao lee
Backpatch-through: 13
Discussion: https://www.postgresql.org/message-id/18929-077d6b7093b176e2@postgresql.org
Prevent moving the confirmed_flush backwards, as this could lead to data
duplication issues caused by replicating already replicated changes.
This can happen when a client acknowledges an LSN it doesn't have to do
anything for, and thus didn't store persistently. After a restart, the
client can send the prior LSN that it stored persistently as an
acknowledgement, but we need to ignore such an LSN to avoid retreating
confirm_flush LSN.
Diagnosed-by: Zhijie Hou <houzj.fnst@fujitsu.com>
Author: shveta malik <shveta.malik@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Tested-by: Nisha Moond <nisha.moond412@gmail.com>
Backpatch-through: 13
Discussion: https://postgr.es/m/CAJpy0uDZ29P=BYB1JDWMCh-6wXaNqMwG1u1mB4=10Ly0x7HhwQ@mail.gmail.com
Discussion: https://postgr.es/m/OS0PR01MB57164AB5716AF2E477D53F6F9489A@OS0PR01MB5716.jpnprd01.prod.outlook.com
6b94e7a6da adjusted generate_orderedappend_paths() to consider fractional
paths. However, it didn't manage to interpret the tuple_fraction value
correctly. According to the header comment of grouping_planner(), the
tuple_fraction >= 1 specifies the absolute number of expected tuples. That
number must be divided by the expected total number of tuples to get the
actual fraction.
Even though this is a bug fix, we don't backpatch it. The risks of the side
effects of plan changes on stable branches are too high.
Reported-by: Andrei Lepikhov <lepihov@gmail.com>
Discussion: https://postgr.es/m/3ca271fa-ca5c-458c-8934-eb148622b270%40gmail.com
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
In an XMLTABLE expression, columns can be marked NOT NULL, and the
parser internally fabricates an option named "is_not_null" to
represent this. However, the parser also allows users to specify
arbitrary option names. This creates a conflict: a user can
explicitly use "is_not_null" as an option name and assign it a
non-Boolean value, which violates internal assumptions and triggers an
assertion failure.
To fix, this patch checks whether a user-supplied name collides with
the internally reserved option name and raises an error if so.
Additionally, the internal name is renamed to "__pg__is_not_null" to
further reduce the risk of collision with user-defined names.
Reported-by: Евгений Горбанев <gorbanyoves@basealt.ru>
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@kurilemu.de>
Discussion: https://postgr.es/m/6bac9886-65bf-4cec-96bd-e304159f28db@basealt.ru
Backpatch-through: 15
When creating a new PlannerGlobal node in standard_planner(), most
fields are explicitly initialized, but a few are not. This doesn't
cause any functional issues, as makeNode() zeroes all fields by
default. However, the inconsistency is undesirable from a clarity and
maintenance perspective.
This patch explicitly initializes the remaining fields to improve
consistency and readability.
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAMbWs4-TgQHNOiouqGcuHoBqbJjWyx4UxGKxUY3FrF4trGbcPA@mail.gmail.com
As complained about by Valgrind, in commit a379061a22 I failed to
realize that I was causing rd_att->constr->check to become allocated
when no CHECK constraints exist; previously it'd remain NULL. (This was
my bug, not the mentioned commit author's). Fix by making the
allocation conditional, and set ->check to NULL if unallocated.
Reported-by: Yasir <yasir.hussain.shah@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/202505082025.57ijx3qrbx7u@alvherre.pgsql
This must be "return MemoryContextAllocationFailure(context, size, flags)"
instead. The effect of this oversight is that if we got a malloc
failure right here, the code would act as though MCXT_ALLOC_NO_OOM
had been specified, whether it was or not. That would likely lead
to a null-pointer-dereference crash at the unsuspecting call site.
Noted while messing with a patch to improve our Valgrind leak
detection support. Back-patch to v17 where this code came in.
Commit f4ece891fc added the assertion in
an attempt to catch some defects even after VACUUM FULL or REINDEX.
However, IsCatalogTextUniqueIndexOid(tag.relNumber) always returns false
after a relfilenode change, provoking unintended assertion failures.
Reported-by: Adam Guo <adamguo@amazon.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Bug: #18912
Discussion: https://postgr.es/m/18912-a41c9bd0e0ad19b1@postgresql.org
This cleans up the code related to the testing infrastructure of AIO
that used injection points, switching the test code to use the new
facility for injection points added by 371f2db8b0 rather than tweaks
to pass and reset arguments to the callbacks run.
This removes all the dependencies to USE_INJECTION_POINTS in the AIO
code. pgaio_io_call_inj(), pgaio_inj_io_get() and pgaio_inj_cur_handle
are now gone.
Reviewed-by: Greg Burd <greg@burd.me>
Discussion: https://postgr.es/m/Z_y9TtnXubvYAApS@paquier.xyz
The macros INJECTION_POINT() and INJECTION_POINT_CACHED() are extended
with an optional argument that can be passed down to the callback
attached when an injection point is run, giving to callbacks the
possibility to manipulate a stack state given by the caller. The
existing callbacks in modules injection_points and test_aio have their
declarations adjusted based on that.
da7226993f (core AIO infrastructure) and 93bc3d75d8 (test_aio) and
been relying on a set of workarounds where a static variable called
pgaio_inj_cur_handle is used as runtime argument in the injection point
callbacks used by the AIO tests, in combination with a TRY/CATCH block
to reset the argument value. The infrastructure introduced in this
commit will be reused for the AIO tests, simplifying them.
Reviewed-by: Greg Burd <greg@burd.me>
Discussion: https://postgr.es/m/Z_y9TtnXubvYAApS@paquier.xyz
A 'void *' argument suggests that the caller might pass an arbitrary
struct, which is appropriate for functions like libc's read/write, or
pq_sendbytes(). 'uint8 *' is more appropriate for byte arrays that
have no structure, like the cancellation keys or SCRAM tokens. Some
places used 'char *', but 'uint8 *' is better because 'char *' is
commonly used for null-terminated strings. Change code around SCRAM,
MD5 authentication, and cancellation key handling to follow these
conventions.
Discussion: https://www.postgresql.org/message-id/61be9e31-7b7d-49d5-bc11-721800d89d64@eisentraut.org
When creating an explicit Sort node for the outer path of a mergejoin,
we need to determine the number of presorted keys of the outer path to
decide whether explicit incremental sort can be applied. Currently,
this is done by repeatedly calling pathkeys_count_contained_in.
This patch caches the number of presorted outer pathkeys in MergePath,
allowing us to save several calls to pathkeys_count_contained_in. It
can be considered a complement to the changes in commit 828e94c9d.
Reported-by: David Rowley <dgrowleyml@gmail.com>
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Discussion: https://postgr.es/m/CAApHDvqvBireB_w6x8BN5txdvBEHxVgZBt=rUnpf5ww5P_E_ww@mail.gmail.com
When building a ForeignPath for a joinrel, if there's a possibility
that EvalPlanQual will be executed, we must identify a suitable path
for EPQ checks. If the outer or inner path of the chosen path is a
ForeignPath representing a pushed-down join, we replace it with its
fdw_outerpath to ensure that the EPQ check path consists entirely of
local joins.
If the chosen path is a MergePath, and its outer or inner path is a
ForeignPath that is not already well enough ordered, the MergePath
will have non-NIL outersortkeys or innersortkeys indicating the
desired ordering to be created by an explicit Sort node. If we then
replace the outer or inner path with its corresponding fdw_outerpath,
and that path is already sufficiently ordered, we end up in an
inconsistent state: the MergePath has non-NIL outersortkeys or
innersortkeys, and its input path is already properly ordered. This
inconsistency can result in an Assert failure or the addition of a
redundant Sort node.
To fix, check if the new outer or inner path of a MergePath is already
properly sorted, and set its outersortkeys or innersortkeys to NIL if
so.
Bug: #18902
Reported-by: Nikita Kalinin <n.kalinin@postgrespro.ru>
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Discussion: https://postgr.es/m/18902-71c1bed2b9f7c46f@postgresql.org
A few places that access this catalog don't set up an active
snapshot before potentially accessing its TOAST table. However,
roname (the replication origin name) is the only varlena column, so
this is only a problem if the name requires out-of-line storage.
This commit removes its TOAST table to avoid needing to set up a
snapshot. It also places a limit on replication origin names so
that attempts to set long names will fail with a more user-friendly
error. Those chosen limit of 512 bytes should be sufficient to
avoid "row is too big" errors independent of BLCKSZ, but it should
also be lenient enough for all reasonable use-cases.
Bumps catversion.
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Euler Taveira <euler@eulerto.com>
Reviewed-by: Nisha Moond <nisha.moond412@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/ZvMSUPOqUU-VNADN%40nathan
nbtree array index scans could fail to return matching tuples in rare
cases where the missed tuples cover key space that the scan's arrays
incorrectly indicate has already been read. These cases involved nearby
tuples with NULL values that were evaluated using a skip array key while
in pstate.forcenonrequired mode.
To fix, prevent forcenonrequired mode from prematurely advancing the
scan's array keys beyond key space that the scan has yet to read tuples
from: reset the scan's array keys (to the first elements in the current
scan direction) before the _bt_checkkeys call for pstate.finaltup. That
way _bt_checkkeys starts from a clean slate, which ensures that it will
call _bt_advance_array_keys (while passing it sktrig_required=true).
This reliably restores the invariant that the scan's arrays always
accurately track its progress through the index's key space (at least
when the scan is "between pages").
Oversight in commit 8a510275, which optimized nbtree search scan key
comparisons.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://postgr.es/m/CAH2-WzmodSE+gpTd1CRGU9ez8ytyyDS+Kns2r9NzgUp1s56kpw@mail.gmail.com
Be more conservative when performing a scheduled recheck of an nbtree
scan's array keys once on the next page, having set so->scanBehind: back
out of reading the page (perform another primitive scan instead) when
the next page's high key/finaltup has an untruncated prefix of matching
values and truncated suffix attributes associated with lower-order keys.
In other words, stop assuming that the lower-order keys have been
satisfied by the truncated suffix attributes in this context (only do so
when considering scheduling a recheck within _bt_advance_array_keys).
The new behavior is more logical: if the next page read after setting
so->scanBehind can only contain tuples that are themselves "behind the
scan", that's reason enough to cut our losses. In general, when we set
so->scanBehind, we only expect to perform one recheck on the next page
to make a final decision about whether or not to continue the current
primitive index scan. It seems unprincipled for the recheck to allow a
_bt_readpage to continue unless the scan's arrays will advance/unless
the page might actually contain relevant tuples.
In practice it is highly unlikely that things will line up like this
(the untruncated prefix of attribute values from the next page's high
key is seldom an exact match for their corresponding array's current
element following array advancement on the original/previous page).
That gives us all the more reason to keep things simple and consistent.
This was arguably an oversight in commit 9a2e2a285a, which improved
nbtree array primitive scan scheduling.
Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-WzkXzJajgyW-pCQ7vaDPhaT3huU+Zw_j448rpCBEsu2YOQ@mail.gmail.com
fc069a3a63 implemented Self-Join Elimination (SJE) and put related logic
to ChangeVarNodes_walker(). This commit provides refactoring to remove the
SJE-related logic from ChangeVarNodes_walker() but adds a custom callback to
ChangeVarNodesExtended(), which has a chance to process a node before
ChangeVarNodes_walker(). Passing this callback to ChangeVarNodesExtended()
allows SJE-related node handling to be kept within the analyzejoins.c.
Reported-by: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/CAMbWs49PE3CvnV8vrQ0Dr%3DHqgZZmX0tdNbzVNJxqc8yg-8kDQQ%40mail.gmail.com
Author: Andrei Lepikhov <lepihov@gmail.com>
Author: Alexander Korotkov <aekorotkov@gmail.com>
IO workers are treated as auxiliary processes. The comments fixed in
this commit stated that there could be only one auxiliary process of
each BackendType at the same time. This is not true for IO workers, as
up to MAX_IO_WORKERS of them can co-exist at the same time.
Author: Cédric Villemain <Cedric.Villemain@data-bene.io>
Co-authored-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/e4a3ac45-abce-4b58-a043-b4a31cd11113@Data-Bene.io
With GB18030 as source encoding, applications could crash the server via
SQL functions convert() or convert_from(). Applications themselves
could crash after passing unterminated GB18030 input to libpq functions
PQescapeLiteral(), PQescapeIdentifier(), PQescapeStringConn(), or
PQescapeString(). Extension code could crash by passing unterminated
GB18030 input to jsonapi.h functions. All those functions have been
intended to handle untrusted, unterminated input safely.
A crash required allocating the input such that the last byte of the
allocation was the last byte of a virtual memory page. Some malloc()
implementations take measures against that, making the SIGSEGV hard to
reach. Back-patch to v13 (all supported versions).
Author: Noah Misch <noah@leadboat.com>
Author: Andres Freund <andres@anarazel.de>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Backpatch-through: 13
Security: CVE-2025-4207
fc069a3a63 implemented Self-Join Elimination (SJE) and put related logic
to ChangeVarNodes_walker(). This commit provides refactoring to remove the
SJE-related logic from ChangeVarNodes_walker() but adds a custom callback to
ChangeVarNodesExtended(), which has a chance to process a node before
ChangeVarNodes_walker(). Passing this callback to ChangeVarNodesExtended()
allows SJE-related node handling to be kept within the analyzejoins.c.
Reported-by: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/CAMbWs49PE3CvnV8vrQ0Dr%3DHqgZZmX0tdNbzVNJxqc8yg-8kDQQ%40mail.gmail.com
Author: Andrei Lepikhov <lepihov@gmail.com>
Author: Alexander Korotkov <aekorotkov@gmail.com>
The previous code was allocating more memory and copying more data than
necessary because it specified the wrong PgStat_KindInfo member as the
size argument for MemoryContextAlloc and memcpy, respectively.
Although these issues exist since 5891c7a8e, there have been no reports
from the field. So for now, it seems sufficient to fix them in master.
Author: Etsuro Fujita <etsuro.fujita@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Gurjeet Singh <gurjeet@singh.im>
Discussion: https://postgr.es/m/CAPmGK15eTRCZTnfgQ4EuBNo%3DQLYGFEbXS_7m2dXqtkcT7L8qrQ%40mail.gmail.com
Also adjust the phrasing in the comments.
Author: Etsuro Fujita <etsuro.fujita@gmail.com>
Author: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Gurjeet Singh <gurjeet@singh.im>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAPmGK17%3DPHSDZ%2B0G6jcj12buyyE1bQQc3sbp1Wxri7tODT-SDw%40mail.gmail.com
Backpatch-through: 15
Consistently prevent nbtree array advancement from treating a scankey as
required when operating in pstate.forcenonrequired mode. Otherwise, we
risk a NULL pointer dereference. This was possible in the path where
_bt_check_compare is called to recheck a tuple that advanced all of the
scan's arrays to matching values: its continuescan=false handling
expects _bt_advance_array_keys to have been called with a valid pstate,
but it'll always be NULL during sktrig_required=false calls (which is
how _bt_advance_array_keys must be called when pstate.forcenonrequired).
Oversight in commit 8a510275, which optimized nbtree search scan key
comparisons.
Author: Peter Geoghegan <pg@bowt.ie>
Reported-By: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://postgr.es/m/CAHgHdKsn2W=gPBmj7p6MjQFvxB+zZDBkwTSg0o3f5Hh8rkRrsA@mail.gmail.com
Discussion: https://postgr.es/m/CAH2-WzmodSE+gpTd1CRGU9ez8ytyyDS+Kns2r9NzgUp1s56kpw@mail.gmail.com
To insert the merged GIN entries in _gin_parallel_merge, the leader
calls ginEntryInsert(). This may allocate memory, e.g. for a new leaf
tuple. This was allocated in the PortalContext, and kept until the end
of the index build. For most GIN indexes the amount of leaked memory is
negligible, but for custom opclasses with large keys it may cause OOMs.
Fixed by calling ginEntryInsert() in a temporary memory context, reset
after each insert. Other ginEntryInsert() callers do this too, except
that the context is reset after batches of inserts. More frequent resets
don't seem to hurt performance, it may even help it a bit.
Report and fix by Vinod Sridharan.
Author: Vinod Sridharan <vsridh90@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CAFMdLD4p0VBd8JG=Nbi=BKv6rzFAiGJ_sXSFrw-2tNmNZFO5Kg@mail.gmail.com
We only need a tuplestore if we're actually going to accumulate
multiple result tuples. Obviously then we don't need one for non-set-
returning functions; but even a SRF doesn't need one if we decide to
use "lazyEval" (one row at a time) mode. In these cases, it's
sufficient to use the junkfilter's result slot to hold the single row
that's due to be returned. We just need to "materialize" that slot
to ensure it holds onto the data past shutdown of the sub-executor.
The original intent of this patch was partially to save a few cycles
(by not putting tuples into a tuplestore only to pull them back out
immediately), but mostly to ensure that we don't use a tuplestore
in non-set-returning functions. That's because I had concerns
about whether a tuplestore is safe to keep across queries,
which was possible for functions invoked via long-lived FmgrInfos
such as those kept in the typcache. There are no cases where SRFs
are called that way, so getting rid of the tuplestore in non-SRFs
should make things safer.
However, it emerges that running fmgr_sql in a short-lived context
(as 595d1efed made it do) makes the existing coding unsafe anyway:
we can end up with a long-lived TupleTableSlot holding a freeable
reference to a short-lived tuple, resulting in a double-free crash.
Not trying to pull tuples out of the tuplestore using that slot
dodges the problem, so I'm going to commit this now rather than
invent a band-aid solution for v18.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/2443532.1744919968@sss.pgh.pa.us
Discussion: https://postgr.es/m/9f975803-1a1c-4f21-b987-f572e110e860@gmail.com
For self-referencing foreign keys in partitioned tables, we weren't
handling creation of pg_constraint rows during CREATE TABLE PARTITION AS
as well as ALTER TABLE ATTACH PARTITION. This is an old bug -- mostly,
we broke this in 614a406b4f while trying to fix it (so 12.13, 13.9,
14.6 and 15.0 and up all behave incorrectly). This commit reverts part
of that with additional fixes for full correctness, and installs more
tests to verify the parts we broke, not just the catalog contents but
also the user-visible behavior.
Backpatch to all live branches. In branches 13 and 14, commit
46a8c27a72 changed the behavior during DETACH to drop a FK
constraint rather than trying to repair it, because the complete fix of
repairing catalog constraints was problematic due to lack of previous
fixes. For this reason, the test behavior in those branches is a bit
different. However, as best as I can tell, the fix works correctly
there.
In release notes we have to recommend that all self-referencing foreign
keys on partitioned tables be recreated if partitions have been created
or attached after the FK was created, keeping in mind that violating
rows might already be present on the referencing side.
Reported-by: Guillaume Lelarge <guillaume@lelarge.info>
Reported-by: Matthew Gabeler-Lee <fastcat@gmail.com>
Reported-by: Luca Vallisa <luca.vallisa@gmail.com>
Discussion: https://postgr.es/m/CAECtzeWHCA+6tTcm2Oh2+g7fURUJpLZb-=pRXgeWJ-Pi+VU=_w@mail.gmail.com
Discussion: https://postgr.es/m/18156-a44bc7096f0683e6@postgresql.org
Discussion: https://postgr.es/m/CAAT=myvsiF-Attja5DcWoUWh21R12R-sfXECY2-3ynt8kaOqjw@mail.gmail.com
The extension_control_path setting (commit 4f7f7b0375) did not
support extensions that set a custom "directory" setting in their
control file. Very few extensions use that and during the discussion
on the previous commit it was suggested to maybe remove that
functionality. But a fix was easier than initially thought, so this
just adds that support. The fix is to use the control->control_dir as
a share dir to return the path of the extension script files.
To make this work more sensibly overall, the directory suffix
"extension" is no longer to be included in the extension_control_path
value. To quote the patch, it would be
-extension_control_path = '/usr/local/share/postgresql/extension:/home/my_project/share/extension:$system'
+extension_control_path = '/usr/local/share/postgresql:/home/my_project/share:$system'
During the initial patch, there was some discussion on which of these
two approaches would be better, and the committed patch was a 50/50
decision. But the support for the "directory" setting pushed it the
other way, and also it seems like many people didn't like the previous
behavior much.
Author: Matheus Alcantara <mths.dev@pm.me>
Reviewed-by: Christoph Berg <myon@debian.org>
Reviewed-by: David E. Wheeler <david@justatheory.com>
Discussion: https://www.postgresql.org/message-id/flat/aAi1VACxhjMhjFnb%40msg.df7cb.de#0cdf7b7d727cc593b029650daa3c4fbc
Make an nbtree array preprocessing assertion account for scans that add
fewer skip arrays than initially expected due to preprocessing finding
an unsatisfiable array qual.
Oversight in commit 92fe23d9.
Author: Peter Geoghegan <pg@bowt.ie>
Reported-By: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://postgr.es/m/CAHgHdKtQMhHy5qcB3KqCcGiW-Rp8P7KzUFRa9ZMKUiv6zen7LQ@mail.gmail.com
We try to avoid using strncpy() due to the ease of which it can
be misused. Convert this callsite to use strlcpy() instead to
match similar codepaths in this file.
Suggested-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/2a796830-de2d-4030-b480-d673f6cc5d94@eisentraut.org
When copying the string strncpy won't add nul termination since
the string length is equal to the length specified. Explicitly
set a nul terminator after copying to properly terminate. Found
via post-commit review.
Author: Rahila Syed <rahilasyed90@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/CAH2L28vt16C9xTuK+K7QZvtA3kCNWXOEiT=gEekUw3Xxp9LVQw@mail.gmail.com
This reverts commit 38da053463, which
attempted to preserve our ability to start with only 60 semaphores.
Subsequent changes (particularly 55b454d0e) have put that idea pretty
much permanently out of reach: people wishing to use Postgres v18 on
OpenBSD or NetBSD will have no choice but to increase those platforms'
default values of SEMMNI and SEMMNS.
Hence, revert 38da05346's changes in SEMAS_PER_SET and the minimum
tested value of max_connections. Adjust a comment from the subsequent
patch 6d0154196, and tweak the wording in runtime.sgml to make it
clear that changing SEMMNI/SEMMNS is no longer even a little bit
optional on these platforms.
Although 38da05346 was later back-patched into v17, leave that branch
alone: it's still capable of starting with 60 semaphores, and there's
no reason to break that.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/E1tuZNv-0037Gs-34@gemulon.postgresql.org
Discussion: https://postgr.es/m/1052019.1745947915@sss.pgh.pa.us
This commit fixes two bug in ChangeVarNodes_walker() function.
* When considering RestrictInfo, walk down to its clauses based on the
presense of relid to be deleted not just in clause_relids but also in
required_relids.
* Incrementally adjust num_base_rels based on the change of clause_relids
instead of recalculating it using clause_relids, which could contain
outer-join relids.
Reported-by: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/CAMbWs49PE3CvnV8vrQ0Dr%3DHqgZZmX0tdNbzVNJxqc8yg-8kDQQ%40mail.gmail.com
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
The slot synchronization skips updating the confirmed_flush LSN of the
local slot if the local slot has a newer catalog_xmin or restart_lsn, but
still allows updating the two_phase and two_phase_at fields of the slot.
This opens up a window for the prepared transactions between old
confirmed_flush LSN and two_phase_at to unexpectedly get decoded and sent
to the downstream after promotion. Then, while decoding the commit
prepared the assert will fail, which expects that the prepare hasn't been
sent to the downstream.
The fix is to skip updating the other slot fields when we are skipping to
update the confirmed_flush LSN of the slot.
We didn't backpatch this commit as two_phase_at was not synced in back
branches, which means prepared transactions won't be unexpectedly sent to
downstream.
We discovered this problem while analyzing BF failure reported in the
discussion link.
Reliably reproducing this issue without a debugger is difficult. Given
its rarity, adding specific injection point to test it doesn't seem
worthwhile, so we won't be adding a dedicated test case.
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: shveta malik <shveta.malik@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/OS0PR01MB5716B44052000EB91EFAE60E94BC2@OS0PR01MB5716.jpnprd01.prod.outlook.com
Index vacuuming and [auto]prewarm AIO concurrency should be governed by
maintenance_io_concurrency. As such, pass those read stream users the
READ_STREAM_MAINTENANCE flag which will calculate their read stream
distance with maintenance_io_concurrency instead of
effective_io_concurrency. This was an oversight in the original commits
making those operations use the read stream API.
Discussion: https://postgr.es/m/flat/CAAKRu_aopDxTo4b41Mt_7Zc-z0_ngocrY8SFCCY6Aph1HgwuNw%40mail.gmail.com
Checking if another primitive scan is required after all once the next
leaf page was moved from _bt_checkkeys to its _bt_readpage caller by
commit 9a2e2a28. Update a comment that incorrectly described the
recheck mechanism as something that takes place in _bt_checkkeys.
Also fix an older typo in related code comments.
_bt_check_compare neglected to handle a case that can arise when the
scan's keys are temporarily treated as nonrequired, as an optimization:
whenever a NULL tuple value was encountered that had a skip array whose
current element wasn't already NULL, _bt_check_compare failed to advance
the array to the NULL element. This allowed _bt_check_compare to fail
to return matching tuples containing a NULL value (though only with an
array column that came before a skip array column with NULLs, and only
during _bt_readpage calls that set pstate.forcenonrequired=true on a
page where the higher-order column also had to advance).
To fix, teach _bt_check_compare to handle this case just like any other
case where a skip array key is unsatisfied and must be advanced directly
(due to the key being considered a nonrequired key).
Oversight in commit 8a510275, which optimized nbtree search scan key
comparisons with skip arrays.
Author: Peter Geoghegan <pg@bowt.ie>
Reported-By: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://postgr.es/m/CAHgHdKtLFWZcjr87hMH0hYDHgcifu4Tj7iHz-xh8qsJREt5cqA@mail.gmail.com
During logical decoding, we advance catalog_xmin of logical too early in
fast_forward mode, resulting in required catalog data being removed by
vacuum. This mode is normally used to advance the slot without processing
the changes, but we still can't let the slot's xmin to advance to an
incorrect value.
Commit f49a80c481 fixed a similar issue where the logical slot's
catalog_xmin was getting advanced prematurely during non-fast-forward
mode. During xl_running_xacts processing, instead of directly advancing
the slot's xmin to the oldest running xid in the record, it allowed the
xmin to be held back for snapshots that can be used for
not-yet-replayed transactions, as those might consider older txns as
running too. However, it missed the fact that the same problem can happen
during fast_forward mode decoding, as we won't build a base snapshot in
that mode, and the future call to get_changes from the same slot can miss
seeing the required catalog changes leading to incorrect reslts.
This commit allows building the base snapshot even in fast_forward mode to
prevent the early advancement of xmin.
Reported-by: Amit Kapila <amit.kapila16@gmail.com>
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: shveta malik <shveta.malik@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 13
Discussion: https://postgr.es/m/CAA4eK1LqWncUOqKijiafe+Ypt1gQAQRjctKLMY953J79xDBgAg@mail.gmail.com
Discussion: https://postgr.es/m/OS0PR01MB57163087F86621D44D9A72BF94BB2@OS0PR01MB5716.jpnprd01.prod.outlook.com
wait_event_types.h is generated by the code, and included wait_event.h.
wait_event.h did the opposite move, including wait_event_types.h,
causing a circular dependency between both.
wait_event_types.h only needs to now about the wait event classes, so
this information is moved into its own file, and wait_event_types.h uses
this new header so as it does not depend anymore on wait_event.h.
Note that such errors can be found with clang-tidy, with commands like
this one:
clang-tidy source_file.c --checks=misc-header-include-cycle -- \
-I/install/path/include/ -I/install/path/include/server/
Issue introduced by fa88928470.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/350192.1745768770@sss.pgh.pa.us
fc069a3a63 implements Self-Join Elimination (SJE), which can remove base
relations when appropriate. However, regressions tests for SJE only cover
the case when placeholder variables (PHVs) are evaluated and needed only
in a single base rel. If this baserel is removed due to SJE, its clauses,
including PHVs, will be transferred to the keeping relation. Removing these
PHVs may trigger an error on plan creation -- thanks to the b3ff6c742f for
detecting that.
This commit skips removal of PHVs during SJE. This might also happen that
we skip the removal of some PHVs that could be removed. However, the overhead
of extra PHVs is small compared to the complexity of analysis needed to remove
them.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Alena Rybakina <a.rybakina@postgrespro.ru>
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
Reviewed-by: Richard Guo <guofenglinux@gmail.com>
This cleans up some loose ends left by commit e8ca9ed1d. I hadn't
looked closely enough at these places before, but now I have.
The use of double-quoted #includes for Perl headers in plperl_system.h
seems to be simply a mistake introduced in 6c944bf3c and faithfully
copied forward since then. (I had thought possibly it was required
by some weird Windows build setup, but there's no evidence of that in
our history.)
The occurrences in SectionMemoryManager.h and SectionMemoryManager.cpp
evidently stem from those files' origin as LLVM code. It's
understandable that LLVM would treat their own files as needing
double-quoted #includes; but they're still system headers to us.
I also applied the same check to *.c files, and found a few other
random incorrect usages in both directions.
Our ECPG headers and test files routinely use angle brackets to refer
to ECPG headers. I left those usages alone, since it seems reasonable
for an ECPG user to regard those headers as system headers.
c4d5cb71d2 adjusted the fast-path locking code to allow some
configuration of the number of fast-path locking slots via the
max_locks_per_transaction GUC. In that commit the FAST_PATH_REL_GROUP()
macro used integer division to determine the fast-path locking group slot
to use for the lock.
The divisor in this case is always a power-of-two value. Here we swap
out the divide by a bitwise-AND, which is a significantly faster
operation to perform.
In passing, adjust the code that's setting FastPathLockGroupsPerBackend
so that it's more clear that the value being set is a power-of-two.
Also, adjust some comments in the area which contained some magic
numbers. It seems better to justify the 1024 upper limit in the
location where the #define is made instead of where it is used.
Author: David Rowley <drowleyml@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CAApHDvodr3bcnpxcs7+k-3cFwYR0tP-BYhyd2PpDhe-bCx9i=g@mail.gmail.com
10f6646847 intended to limit the value of io_combine_limit to the minimum of
io_combine_limit and io_max_combine_limit. To avoid issues with interdependent
GUCs, it introduced io_combine_limit_guc and set io_combine_limit in assign
hooks. That plan was thwarted by guc_tables.c accidentally still referencing
io_combine_limit, instead of io_combine_limit_guc. That lead to the GUC
machinery overriding the work done in the assign hooks, potentially leaving
io_combine_limit with a too high value.
The consequence of this bug was that when running with io_combine_limit >
io_combine_limit_guc the AIO machinery would not have reserved large enough
iovec and IO data arrays, with one IO's arrays overlapping with another IO's,
leading to total confusion.
To make such a problem easier to detect in the future, add assertions to
pgaio_io_set_handle_data_* checking the length is smaller than
io_max_combine_limit (not just PG_IOV_MAX).
It'd be nice to have a few tests for this, but it's not entirely obvious how
to do so portably.
As remarked upon by Tom, the GUC assignment hooks really shouldn't set the
underlying variable, that's the job of the GUC machinery. Change that as well.
Discussion: https://postgr.es/m/c5jyqnuwrpigd35qe7xdypxsisdjrdba5iw63mhcse4mzjogxo@qdjpv22z763f
pgaio_io_reclaim() reset the fields in PgAioHandle before updating the state
to IDLE or incrementing the generation. For most things that's OK, but for
pg_get_aios() it is not - if it copied the PgAioHandle while fields were being
reset, we wouldn't detect that and could call
pgaio_io_get_target_description() with ioh->target == PGAIO_TID_INVALID,
leading to a crash.
Fix this issue by incrementing the generation and state earlier, before
resetting.
Also add an assertion to pgaio_io_get_target_description() for the target to
be valid - that'd have made this case a bit easier to debug. While at it,
add/update a few related assertions.
Author: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/062daca9-dfad-4750-9da8-b13388301ad9@gmail.com
Not having this check would produce a core dump at startup when running
pgstat_read_statsfile(), in the case where the information of a stats
kind for an entry in the dshash could not be found. The same check
already happens for fixed-numbered stats and entries that are stored
with their names. This issue can be seen with custom stats kinds.
Note that this problem can be reproduced what what is in the core code:
- Tweak the test module injection_points to not load the fixed-numbered
stats part, leaving only the variable-numbered stats.
- Create an instance with injection_points defined in
shared_preload_libraries.
- Create a pgstats entry by attaching and running a point.
- Restart the server without shared_preload_libraries. The startup
process detects that something is wrong and reports a WARNING.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/aAieZAvM+K1d89R2@ip-10-97-1-34.eu-west-3.compute.internal
One place in hash_create() used DynaHashAlloc() as a convenient
shorthand for MemoryContextAlloc(). That was fine when it was
written, but it stopped being fine when 9c911ec06 changed
DynaHashAlloc() to use MCXT_ALLOC_NO_OOM (mea culpa). Change
the code to call plain MemoryContextAlloc() as intended.
I think that this bug may be unreachable in practice, since we now
always create AllocSets with some space already allocated, so that
an OOM failure here for a non-shared hash table should be impossible
(with a hash table name of reasonable length anyway). And there
aren't enough shared hash tables to make a crash for one of those
probable. Nonetheless it's clearly not operating as designed, so
back-patch to v16 where 9c911ec06 came in.
Reported-by: Maksim Korotkov <m.korotkov@postgrespro.ru>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/219bdccd460510efaccf90b57e5e5ef2@postgrespro.ru
Backpatch-through: 16
b85a9d046e introduced a new RelIdToTypeIdCacheHash, whose entries should
exist for typecache entries with TCFLAGS_HAVE_PG_TYPE_DATA flag set or any
of TCFLAGS_OPERATOR_FLAGS set or tupDesc set. However, TypeCacheOpcCallback(),
which resets TCFLAGS_OPERATOR_FLAGS, was forgotten to update
RelIdToTypeIdCacheHash.
This commit adds a delete_rel_type_cache_if_needed() call to the
TypeCacheOpcCallback() function to maintain RelIdToTypeIdCacheHash after
resetting TCFLAGS_OPERATOR_FLAGS.
Also, this commit fixes the name of the delete_rel_type_cache_if_needed()
function in its mentions in the comments.
Reported-by: Noah Misch
Discussion: https://postgr.es/m/20250411203241.e9.nmisch%40google.com
To estimate with extended statistics, we need to clear the varnullingrels
field in the expression, and duplicates are not allowed in the GroupVarInfo
list. We might re-use add_unique_group_var(), but we don't do so for two
reasons.
1) We must keep the origin_rinfos list ordered exactly the same way as
varinfos.
2) add_unique_group_var() is designed for estimate_num_groups(), where a
larger number of groups is worse. While estimating the number of hash
buckets, we have the opposite: a lesser number of groups is worse.
Therefore, we don't have to remove "known equal" vars: the removed var
may valuably contribute to the multivariate statistics to grow the number
of groups.
This commit adds custom code to estimate_multivariate_bucketsize() to
initialize varinfos properly.
Reported-by: Robins Tharakan <tharakan@gmail.com>
Discussion: https://postgr.es/m/18885-da51324078588253%40postgresql.org
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
When a foreign key constraint is placed on a partitioned table, we
actually make two pg_constraint entries associated with that table.
(I have my doubts about the wisdom of that, but it's been like that
since v12 and post-feature-freeze is no time to be messing with such
entrenched decisions.) The second "child" entry always had a name
generated according to the default rule, "table_column(s)_fkey[nnn]",
even if the primary entry had an unrelated user-specified name. The
trouble with doing that is that the default name could collide with
the user-specified name of some other constraint on the same table.
While we were willing to adjust the generated name to avoid
collisions, that only helps if it's made second; if it's made first
then creation of the other constraint would fail, potentially causing
dump/reload or pg_upgrade failures.
The core of the problem here is that we're infringing on user
namespace, so I doubt that there's any 100% solution other than to
find a way to not need the "child" entry. In the meantime, it seems
like it'd be an improvement to make the child's name be the name of
the parent constraint with an underscore and digit(s) appended as
necessary to make it unique. This rule can in theory fail in the same
way, but it seems much less probable; for one thing, this rule is
guaranteed not to match primary entries having auto-generated names.
(While an auto-generated primary name isn't user-specified to begin
with, it acts like that during dump/reload, so collisions against such
names are definitely possible.)
An additional bonus, visible in some of the regression test cases
that change here, arises from the fact that some error messages
cite the child constraint's name not the parent's. In the
previous approach the two names could be completely unrelated,
leading to user confusion --- the more so since psql's \d command
hides child constraints. With this approach it's hopefully much
clearer which constraint-the-user-knows-about is failing.
However, that does mean that there's user-visible behavior change
occurring here, making it seem like not something to back-patch.
I feel it's not too late for v18, though.
Reported-by: Kirill Reshke <reshkekirill@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Alvaro Herrera <alvherre@kurilemu.de>
Discussion: https://postgr.es/m/CALdSSPhGitjpTfzEMJN-Y2x+Q-5QChSxAsmSJ1-E8mQJLkHOqQ@mail.gmail.com
Commit 3f28b2fcac tried to ensure that the replication origin shouldn't be
advanced in case of an ERROR in the apply worker, so that it can request
the same data again after restart. However, it is possible that an ERROR
was caught and handled by a (say PL/pgSQL) function, and the apply worker
continues to apply further changes, in which case, we shouldn't reset the
replication origin.
Ensure to reset the origin only when the apply worker exits after an
ERROR.
Commit 3f28b2fcac added new function geterrlevel, which we removed in HEAD
as part of this commit, but kept it in backbranches to avoid breaking any
applications. A separate case can be made to have such a function even for
HEAD.
Reported-by: Shawn McCoy <shawn.the.mccoy@gmail.com>
Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 16, where it was introduced
Discussion: https://postgr.es/m/CALsgZNCGARa2mcYNVTSj9uoPcJo-tPuWUGECReKpNgTpo31_Pw@mail.gmail.com
This assertion, based on pending_since (timestamp used to prevent stats
reports to be too frequent or should a partial flush happen), is reached
when it is found that no data can be flushed but a previous call of
pgstat_report_stat() determined that some stats data has been found as
in need of a flush. So pending_since is set when some stats data is
pending (in non-force mode) or if report attempts are too frequent, and
reset to 0 once all stats have been flushed.
Since 5cbbe70a9c, WAL senders have begun to report their stats on a
periodic basis for IO stats in v16~ and backend stats on HEAD, creating
some friction with the concurrent pgstat_report_stat() calls that can
happen in the context of a WAL sender (shutdown callback doing a final
report or backend-related code paths). This problem is the cause of
spurious failures in the TAP tests.
In theory, this assertion can be also reached in v15, even if that's
very unlikely. For example, a process, say a background worker, could
do periodic and direct stats flushes with concurrent calls of
pgstat_report_stat() that could cause conflicting values of
pending_since. This can be done with WAL or SLRU stats flushes using
pgstat_flush_wal() or pgstat_slru_flush(). HEAD makes this situation
easier to happen with custom cumulative stats.
This commit removes the assertion altogether, per discussion, as it is
more useful to keep the state of things as they are for the WAL sender.
The assertion could use a special state based on for example
am_walsender, but I doubt that this would be meaningful in the long run
based on the other arguments raised while discussing this issue.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Reported-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/1489124.1744685908@sss.pgh.pa.us
Discussion: https://postgr.es/m/dwrkeszz6czvtkxzr5mqlciy652zau5qqnm3cp5f3p2po74ppk@omg4g3cc6dgq
Backpatch-through: 15
This error message was 'runaway "struct_name"', which isn't all
that clear; I think 'could not find closing brace for "struct_name"'
is better. Also, provide the location of the struct start using the
script's usual '$file:$lineno' style.
Bug: #18901
Reported-by: Clemens Ruck <clemens.ruck@t-online.de>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18901-424272abe01357e6@postgresql.org
This injection point was named "AtEOXact_Inval-with-transInvalInfo", not
respecting the implied naming convention that injection points should
use lower-case characters, with terms separated by dashes. All the
other points defined in the tree follow this style, so let's be more
consistent.
Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Aleksander Alekseev <aleksander@timescale.com>
Discussion: https://postgr.es/m/OSCPR01MB14966E14C1378DEE51FB7B7C5F5B32@OSCPR01MB14966.jpnprd01.prod.outlook.com
Backpatch-through: 17
Word boundaries are based on whether a character is alphanumeric or
not. For the PG_UNICODE_FAST collation, alphanumeric includes
non-ASCII digits; whereas for the PG_C_UTF8 collation, it only
includes digits 0-9. Pass down the right information from the
pg_locale_t into initcap_wbnext to differentiate the behavior.
Reported-by: Noah Misch <noah@leadboat.com>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20250417135841.33.nmisch@google.com
exec_replication_command created a cmd_context to work in and
then deleted it on exit. This is pretty dangerous because
some replication commands start/finish transactions. In the
wake of commit 1afe31f03, that could lead to re-selecting a
CurrentMemoryContext that's already been deleted, leading to
hilarity such as a memory context that is its own parent.
To fix, let's make the cmd_context persist across
exec_replication_command calls; instead of deleting it, we'll just
reset it each time. In this way it retains the same identity and
there's no problem if transaction abort restores it as the working
context. It probably even saves a few microseconds to do this.
This fix also ensures that exec_replication_command returns to the
caller (PostgresMain) with the same context active that had been
when it was called (probably MessageContext). The previous
coding could get that wrong too.
Reported-by: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com>
Author: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAO6_XqoJA7-_G6t7Uqe5nWF3nj+QBGn4F6Ptp=rUGDr0zo+KvA@mail.gmail.com
The case of "node == parent" might seem impossible, since we just
allocated the new node. But it's possible if parent is a dangling
reference to a recently-deleted context. In fact, given aset.c's
habit of recycling contexts, it's actually rather likely if that's so.
If we'd had this assertion before, it would have simplified debugging
a recently-identified walsender issue.
Reported-by: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAO6_XqoJA7-_G6t7Uqe5nWF3nj+QBGn4F6Ptp=rUGDr0zo+KvA@mail.gmail.com
Blocking checkpoint phase 2 requires MarkBufferDirty() and
BUFFER_LOCK_EXCLUSIVE; neither suffices by itself. transam/README documents
this, citing SyncOneBuffer(). Update the DELAY_CHKPT_START documentation to
say this. Expand the heap_inplace_update_and_unlock() comment that cites
XLogSaveBufferForHint() as precedent, since heap_inplace_update_and_unlock()
could have opted not to use DELAY_CHKPT_START.
Commit 8e7e672cda added DELAY_CHKPT_START to
heap_inplace_update_and_unlock(). Since commit
bc6bad8857 reverted it in non-master branches,
no back-patch.
Discussion: https://postgr.es/m/20250406180054.26.nmisch@google.com
Commit 7102070329 fixed a similar bug, but
it missed the case of database-wide ANALYZE ("use_own_xacts" mode).
Commit a07e03fd8f changed consequences
from silent discard of a pg_class stats (relpages et al.) update to
ERROR "tuple to be updated was already modified". Losing a relpages
update of an ON COMMIT DELETE ROWS table was negligible, but a
COMMIT-time error isn't negligible. Back-patch to v13 (all supported
versions).
Reported-by: Richard Guo <guofenglinux@gmail.com
Reported-by: Robins Tharakan <tharakan@gmail.com>
Discussion: https://postgr.es/m/CAMbWs4-XwMKMKJ_GT=p3_-_=j9rQSEs1FbDFUnW9zHuKPsPNEQ@mail.gmail.com
Backpatch-through: 13
1349d2790 added support so that aggregate functions with an ORDER BY or
DISTINCT clause could make use of presorted inputs to avoid an implicit
sort within nodeAgg.c. That commit failed to consider that a FILTER
clause may exist that filters rows before the aggregate function
arguments are evaluated. That can be problematic if an aggregate
argument contains an expression which could error out during evaluation.
It's perfectly valid to want to have a FILTER clause which eliminates
such values, and with the pre-sorted path added in 1349d2790, it was
possible that the planner would produce a plan with a Sort node above
the Aggregate to perform the sort on the aggregate's arguments long before
the Aggregate node would filter out the non-matching values.
Here we fix this by inspecting ORDER BY / DISTINCT aggregate functions
which have a FILTER clause to see if the aggregate's arguments are
anything more complex than a Var or a Const. Evaluating these isn't
going to cause an error. If we find any non-Var, non-Const parameters
then the planner will now opt to perform the sort in the Aggregate node
for these aggregates, i.e. disable the presorted aggregate optimization.
An alternative fix would have been to completely disallow the presorted
optimization for Aggrefs with any FILTER clause, but that wasn't done as
that could cause large performance regressions for queries that see
significant gains from 1349d2790 due to presorted results coming in from
an Index Scan.
Backpatch to 16, where 1349d2790 was introduced
Author: David Rowley <dgrowleyml@gmail.com>
Reported-by: Kaimeh <kkaimeh@gmail.com>
Diagnosed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAK-%2BJz9J%3DQ06-M7cDJoPNeYbz5EZDqkjQbJnmRyQyzkbRGsYkA%40mail.gmail.com
Backpatch-through: 16
The format of the injection point names used by the AIO code does not
match the existing naming convention used everywhere else in the code,
so let's be consistent. These points are used in test_aio.
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Discussion: https://postgr.es/m/Z_yTB80bdu1sYDqJ@paquier.xyz
Both pg_get_process_memory_contexts() and pg_backend_memory_contexts
have 1-based levels, whereas pg_log_backend_memory_contexts() was using
0-based levels. Align these.
This results in slightly saner behavior from MemoryContextStatsDetail()
in regards to the max_level. Previously it would stop at 1 level before
the maximum requested level rather than at that level.
Reported-by: Atsushi Torikoshi <torikoshia@oss.nttdata.com>
Author: Atsushi Torikoshi <torikoshia@oss.nttdata.com>
Author: David Rowley <drowleyml@gmail.com
Reviewed-by: Melih Mutlu <m.melihmutlu@gmail.com>
Reviewed-by: Rahila Syed <rahilasyed90@gmail.com>
Discussion: https://postgr.es/m/395ea5d4fe190480efa95bf533485c70@oss.nttdata.com
The "children" list won't be used until "got_children" has been set
true, but older compilers don't get that; about half a dozen
buildfarm animals are warning about this. Issue added by 11ff192b5.
While here, improve slightly-shaky grammar in comment.
Discussion: https://postgr.es/m/2057835.1744833309@sss.pgh.pa.us
This gets rid of repetitive get_typlen calls in postquel_sub_params,
which show up as costing a few percent of the runtime in simple test
cases (more with more parameters).
In combination with the preceding patches, this gets us most of the
way back down to the amount of per-call overhead that functions.c
had before commit 0dca5d68d. There are some more things that could
be done, but this seems like an okay place to stop for v18.
At this point, the only data structures we allocate directly in
fcontext are the SQLFunctionCache struct itself, the ParamListInfo
struct, and the execution_state array, all of which are small and
perfectly capable of being re-used across executions of the same
FmgrInfo. Hence, let's give them the same lifespan as the FmgrInfo.
This step gets rid of the separate SQLFunctionLink struct and makes
fn_extra point to SQLFunctionCache again. We also get rid of the
separate fcontext memory context and allocate these items directly
in fn_mcxt.
For notational simplicity, SQLFunctionCache still has an fcontext
field, but it's just a copy of fn_mcxt.
The motivation for this is to allow these structures to live as
long as the FmgrInfo and be re-used across calls, restoring the
original design without its propensity for memory leaks. This
gets rid of some per-call overhead that we added in 0dca5d68d.
We also make an effort to re-use the JunkFilter and result slot.
Those might need to change if the function definition changes,
so we compromise by rebuilding them if the cached plan changes.
This also moves the tuplestore into fn_mcxt so that it can be
re-used across calls, again undoing a change made in 0dca5d68d.
Put the JunkFilter and its result slot (and thence also
some subsidiary data such as the result tupledesc) into a
separate subcontext "jfcontext". This doesn't accomplish
a lot at this point, because we make a new JunkFilter each
time through the SQL function. However, the plan is to make
the fcontext long-lived, and that raises the possibility
that we'll need a new JunkFilter because the plan for the
result-generating query changes. A separate context makes
it easy to free the obsoleted data when that happens.
Also, instead of always running the sub-executor in fcontext,
make a separate context for it if we're doing lazy eval of
a SRF, and otherwise just run it inside CurrentMemoryContext.
Previously, much of this code ran with CurrentMemoryContext set
to be the function's fcontext, so that we tended to leak a lot of
stuff there. Commit 0dca5d68d dealt with that by releasing the
fcontext at the completion of each SQL function call, but we'd
like to go back to the previous approach of allowing the fcontext
to be query-lifespan. To control the leakage problem, rearrange
the code so that we mostly run in the memory context that fmgr_sql
is called in (which we expect to be short-lived). Notably, this
means that parsing/planning is all done in the short-lived context
and doesn't leak cruft into fcontext.
This patch also fixes the allocation of execution_state records
so that we don't leak them across executions. I set that up
with a re-usable array that contains at least as many
execution_state structs as we need for the current querytree.
The chain structure is still there, but it's not really doing
much for us, and maybe somebody will be motivated to get rid
of it. I'm not though.
This incidentally also moves the call of BlessTupleDesc to be
with the code that creates the JunkFilter. That doesn't make
much difference now, but a later patch will reduce the number
of times the JunkFilter gets made, and we needn't bless the
results any more often than that.
We still leak a fair amount in fcontext, particularly when
executing utility statements, but that's material for a
separate patch step; the point here is only to get rid of
unintentional allocations in fcontext.
Late in the development of commit 0dca5d68d, I added a step to copy
the result tlist we extract from the cached final query, because
I was afraid that that might not last as long as the JunkFilter that
we're passing it off to. However, that turns out to cost a noticeable
number of cycles, and it's really quite unnecessary because the
JunkFilter will not examine that tlist after it's been created.
(ExecFindJunkAttribute would use it, but we don't use that function
on this JunkFilter.) Hence, remove the copy step. For safety,
reset the might-become-dangling jf_targetList pointer to NIL.
In passing, remove DR_sqlfunction.cxt, which we don't use anymore;
it's confusing because it's not entirely clear which context it
ought to point at.
Commit 0bada39c83 fixed a bug of this kind,
which existed in all branches for six days before detection. While the
probability of reaching the trouble was low, the disruption was extreme. No
new backends could start, and service restoration needed an immediate
shutdown. Hence, add this to catch the next bug like it.
The new check in RelationIdGetRelation() suffices to make autovacuum detect
the bug in commit 243e9b40f1 that led to commit
0bada39. This also checks in a number of similar places. It replaces each
Assert(IsTransactionState()) that pertained to a conditional catalog read.
No back-patch for now, but a back-patch of commit 243e9b4 should back-patch
this, too. A back-patch could omit the src/test/regress changes, since back
branches won't gain new index columns.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/20250410191830.0e.nmisch@google.com
Discussion: https://postgr.es/m/10ec0bc3-5933-1189-6bb8-5dec4114558e@gmail.com
estimate_multivariate_ndistinct() is coded to assume the caller handles
passing it a list of GroupVarInfos with unique 'var' fields over the
entire list. 6bb6a62f3 added code which didn't ensure this and that
could result in estimate_multivariate_ndistinct() erroring out with:
ERROR: corrupt MVNDistinct entry
This occurred because estimate_multivariate_ndistinct() first searches
for a set of stats that match to at least two of the given GroupVarInfos
and then later assumes that the MVNDistinctItem.items array of the
best matching stats will have an entry for those two columns. If the
GroupVarInfos List contained a duplicate entry then the same column could
be matched to twice and that could trick the code into thinking we have
>= 2 columns matched in cases where only a single distinct column has been
matched. This could result in a failure to find the correct
MVNDistinctItem in the stats as the array containing those never
contains an item for single columns.
Here we make it more clear that the function needs a distinct set of
GroupVarInfos and also tidy up a few other comments to make things a bit
easier to follow.
Author: David Rowley <drowleyml@gmail.com>
Discussion: https://postgr.es/m/CAApHDvocZCUhM9W9mJ39d6oQz7ePKoqFnao_347mvC-A7QatcQ@mail.gmail.com
Buildfarm member drongo complained because the definitions of these
functions used "const Oid foo" where the forward declarations just
had "Oid foo". (I'm a bit surprised that drongo seems to be the only
complainant.) I chose to fix this by removing the "consts" because
(a) I'm generally not a fan of using const that way, and (b) it was
a minority usage even within these two functions, let alone compared
to the rest of our code base.
Oversight in commit eec0040c4, so no need for back-patch.
We were unnecessarily acquiring AccessExclusiveLock on all child tables
when "ALTER TABLE ONLY sometab ADD PRIMARY KEY" was run on their parent
table, an oversight in commit 14e87ffa5c. This caused deadlocks
during pg_restore of partitioned tables.
The reason to acquire the AEL was that we need to verify that child
tables have the involved columns already marked as not-null; but if the
parent table has an inheritable not-null constraint, then all children
must necessarily be in the correct state already, so we can skip the
check, which avoids acquiring the lock. Reorder the code so that it
works that way. This doesn't change things in the case where the
constraint doesn't exist, but that case is of lesser importance because
it doesn't occur during parallel pg_restore.
While at it, reword some errmsg() and add errhint() to similar cases in
related but not adjacent code.
Diagnosed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Discussion: https://postgr.es/m/67469c1c-38bc-7d94-918a-67033f5dd731@gmx.net
Discussion: https://postgr.es/m/2045026.1743801143@sss.pgh.pa.us
Discussion: https://postgr.es/m/1280408.1744650810@sss.pgh.pa.us
Memoize typically marks cache entries as complete after fully scanning
the inner side of a join. However, in the case of unique joins, we
skip to the next outer tuple as soon as the first matching inner tuple
is found, leaving no opportunity to scan the inner side to completion.
To work around that, we mark cache entries as complete after fetching
the first matching inner tuple in unique joins.
This approach is only safe when all of the join's restriction clauses
are parameterized; otherwise, there is no guarantee that reading just
one tuple from the inner side is sufficient.
Currently, we check for this by verifying that the number of clauses
in ppi_clauses is no less than the number of the join's restriction
clauses. However, this check isn't entirely reliable, as ppi_clauses
includes join clauses available from all outer rels, not just the
current outer rel. This means the check could pass even if a
restriction clause isn't parameterized, as long as another join
clause, which doesn't belong to the current join, is included in
ppi_clauses.
To fix this, we explicitly check whether each restriction clause of
the current join is present in ppi_clauses.
While we're here, remove the XXX comment from the modified code, as
it's not justified; in certain cases, it's not possible to move a join
clause to the inner side.
This is arguably a bugfix, but no backpatch given the lack of field
reports.
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: wenhui qiu <qiuwenhuifx@gmail.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Discussion: https://postgr.es/m/CAMbWs4-8JPouj=wBDj4DhK-WO4+Xdx=A2jbjvvyyTBQneJ1=BQ@mail.gmail.com
If a GENERATED column is declared to have a domain data type where
the domain's constraints disallow null values, INSERT commands failed
because we built a targetlist that included coercing a null constant
to the domain's type. The failure occurred even when the generated
value would have been perfectly OK. This is adjacent to the issues
fixed in 0da39aa76, but we didn't notice for lack of testing a domain
with such a constraint.
We aren't going to use the result of the targetlist entry for the
generated column --- ExecComputeStoredGenerated will overwrite it.
So it's not really necessary that it have the exact datatype of
the generated column. This patch fixes the problem by changing
the targetlist entry to be a null Const of the domain's base type,
which should be sufficiently legal. (We do have to tweak
ExecCheckPlanOutput to accept the situation, though.)
This has been broken since we implemented generated columns.
However, this patch only applies easily as far back as v14, partly
because I (tgl) only carried 0da39aa76 back that far, but mostly
because v14 significantly refactored the handling of INSERT/UPDATE
targetlists. Given the lack of field complaints and the short
remaining support lifetime of v13, I judge the cost-benefit ratio
not good for devising a version that would work in v13.
Reported-by: jian he <jian.universality@gmail.com>
Author: jian he <jian.universality@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CACJufxG59tip2+9h=rEv-ykOFjt0cbsPVchhi0RTij8bABBA0Q@mail.gmail.com
Backpatch-through: 14
Commit 0f21db36d made an assumption that GIN triConsistentFns
would not modify their input entryRes[] arrays. But in fact,
the "shim" triConsistentFn that we use for opclasses that don't
supply their own did exactly that, potentially leading to wrong
answers from a GIN index search. Through bad luck, none of the
test cases that we have for such opclasses exposed the bug.
One response to this could be that the assumption of consistency check
functions not modifying entryRes[] arrays is a bad one, but it still
seems reasonable to me. Notably, shimTriConsistentFn is itself
assuming that with respect to the underlying boolean consistentFn,
so it's sure being self-centered in supposing that it gets to do so.
Fortunately, it's quite simple to fix shimTriConsistentFn to restore
the entry-time state of entryRes[], so let's do that instead.
This issue doesn't affect any core GIN opclasses, since they all
supply their own triConsistentFns. It does affect contrib modules
btree_gin, hstore, and intarray.
Along the way, I (tgl) noticed that shimTriConsistentFn failed to
pick up on a "recheck" flag returned by its first call to the boolean
consistentFn. This may be only a latent problem, since it would be
unlikely for a consistentFn to set recheck for the all-false case
and not any other cases. (Indeed, none of our contrib modules do
that.) Nonetheless, it's formally wrong.
Reported-by: Vinod Sridharan <vsridh90@gmail.com>
Author: Vinod Sridharan <vsridh90@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAFMdLD7XzsXfi1+DpTqTgrD8XU0i2C99KuF=5VHLWjx4C1pkcg@mail.gmail.com
Backpatch-through: 13
Make sure that function declarations use names that exactly match the
corresponding names from function definitions in a few places. These
inconsistencies were all introduced during Postgres 18 development.
This commit was written with help from clang-tidy, by mechanically
applying the same rules as similar clean-up commits (the earliest such
commit was commit 035ce1fe).
synchronous_standby_names cannot be reloaded safely by backends, and the
checkpointer is in charge of updating a state in shared memory if the
GUC is enabled in WalSndCtl, to let the backends know if they should
wait or not for a given LSN. This provides a strict control on the
timing of the waiting queues if the GUC is enabled or disabled, then
reloaded. The checkpointer is also in charge of waking up the backends
that could be waiting for a LSN when the GUC is disabled.
This logic had a race condition at startup, where it would be possible
for backends to not wait for a LSN even if synchronous_standby_names is
enabled. This would cause visibility issues with transactions that we
should be waiting for but they were not. The problem lasts until the
checkpointer does its initial update of the shared memory state when it
loads synchronous_standby_names.
In order to take care of this problem, the shared memory state in
WalSndCtl is extended to detect if it has been initialized by the
checkpointer, and not only check if synchronous_standby_names is
defined. In WalSndCtlData, sync_standbys_defined is renamed to
sync_standbys_status, a bits8 able to know about two states:
- If the shared memory state has been initialized. This flag is set by
the checkpointer at startup once, and never removed.
- If synchronous_standby_names is known as defined in the shared memory
state. This is the same as the previous sync_standbys_defined in
WalSndCtl.
This method gives a way for backends to decide what they should do until
the shared memory area is initialized, and they now ultimately fall back
to a check on the GUC value in this case, which is the best thing that
can be done.
Fortunately, SyncRepUpdateSyncStandbysDefined() is called immediately by
the checkpointer when this process starts, so the window is very narrow.
It is possible to enlarge the problematic window by making the
checkpointer wait at the beginning of SyncRepUpdateSyncStandbysDefined()
with a hardcoded sleep for example, and doing so has showed that a 2PC
visibility test is indeed failing. On machines slow enough, this bug
would cause spurious failures.
In 17~, we have looked at the possibility of adding an injection point
to have a reproducible test, but as the problematic window happens at
early startup, we would need to invent a way to make an injection point
optionally persistent across restarts when attached, something that
would be fine for this case as it would involve the checkpointer. This
issue is quite old, and can be reproduced on all the stable branches.
Author: Melnikov Maksim <m.melnikov@postgrespro.ru>
Co-authored-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/163fcbec-900b-4b07-beaa-d2ead8634bec@postgrespro.ru
Backpatch-through: 13
Sami complained that there's a discrepancy between n_mod_since_analyze
and n_ins_since_vacuum, as the former only accounts for committed changes
and the latter tracks committed and aborted inserts. Nobody seemed
overly concerned that this would cause any concerning issues. The
repercussions, from what I can tell, are limited to causing an
autovacuum to trigger for inserts sooner than it otherwise might. For
typical ratios of commits to aborts, it's unlikely to ever be noticed.
Fixing things to make it so n_ins_since_vacuum only displays committed
inserts would require an additional field in PgStat_TableCounts, which
does not quite seem worthwhile at this stage. This commit just adds a
comment with some details to mention that we know about it, which will
hopefully prevent repeat discussions.
Reported-by: Sami Imseih <samimseih@gmail.com>
Author: David Rowley <drowleyml@gmail.com>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Discussion: https://postgr.es/m/CAApHDvpgV3a-R2EGmPOh0L-x3pHbZpM3y4dySWfy+UqUazwDQA@mail.gmail.com
By inspection, ip_addrsize() can't return a negative result.
(If it could, we'd have way bigger problems elsewhere.)
So delete useless check in network_send(). Most C compilers
are probably perfectly capable of removing this code by
themselves, but it's confusing/misleading.
Bug: #18889
Reported-by: Daniel Elishakov <dan-eli@mail.ru>
Discussion: https://postgr.es/m/18889-73d4f19e953a629e@postgresql.org
Data loss can happen when the DDLs like ALTER PUBLICATION ... ADD TABLE ...
or ALTER TYPE ... that don't take a strong lock on table happens
concurrently to DMLs on the tables involved in the DDL. This happens
because logical decoding doesn't distribute invalidations to concurrent
transactions and those transactions use stale cache data to decode the
changes. The problem becomes bigger because we keep using the stale cache
even after those in-progress transactions are finished and skip the
changes required to be sent to the client.
This commit fixes the issue by distributing invalidation messages from
catalog-modifying transactions to all concurrent in-progress transactions.
This allows the necessary rebuild of the catalog cache when decoding new
changes after concurrent DDL.
We observed performance regression primarily during frequent execution of
*publication DDL* statements that modify the published tables. The
regression is minor or nearly nonexistent for DDLs that do not affect the
published tables or occur infrequently, making this a worthwhile cost to
resolve a longstanding data loss issue.
An alternative approach considered was to take a strong lock on each
affected table during publication modification. However, this would only
address issues related to publication DDLs (but not the ALTER TYPE ...)
and require locking every relation in the database for publications
created as FOR ALL TABLES, which is impractical.
The bug exists in all supported branches, but we are backpatching till 14.
The fix for 13 requires somewhat bigger changes than this fix, so the fix
for that branch is still under discussion.
Reported-by: hubert depesz lubaczewski <depesz@depesz.com>
Reported-by: Tomas Vondra <tomas.vondra@enterprisedb.com>
Author: Shlok Kyal <shlok.kyal.oss@gmail.com>
Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Tested-by: Benoit Lobréau <benoit.lobreau@dalibo.com>
Backpatch-through: 14
Discussion: https://postgr.es/m/de52b282-1166-1180-45a2-8d8917ca74c6@enterprisedb.com
Discussion: https://postgr.es/m/CAD21AoAenVqiMjpN-PvGHL1N9DWnHSq673bfgr6phmBUzx=kLQ@mail.gmail.com
d69d45a5a changed how em_is_child members are stored in
EquivalenceClasses. Children are no longer stored in the ec_members
list. optimizer/README mentioned that most operations "should ignore
child members", but that felt a little untrue now since child members
are now stored in a separate place, they simply won't be found by the
normal means of looking (a foreach loop over ec_members), and if you don't
find them, there's technically no need to "ignore" them.
Here we tweak the wording slightly to reflect the new storage location
for child members.
Reported-by: Amit Langote <amitlangote09@gmail.com>
Author: Amit Langote <amitlangote09@gmail.com>
Author: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CA+HiwqE8v=EuAP_3F_A2xn8zWx+nG_etW_Fe_DvKO-Fkx=+DdQ@mail.gmail.com
This moves/renames some of the functions defined in pg_numa.c:
* pg_numa_get_pagesize() is renamed to pg_get_shmem_pagesize(), and
moved to src/backend/storage/ipc/shmem.c. The new name better reflects
that the page size is not related to NUMA, and it's specifically about
the page size used for the main shared memory segment.
* move pg_numa_available() to src/backend/storage/ipc/shmem.c, i.e. into
the backend (which more appropriate for functions callable from SQL).
While at it, improve the comment to explain what page size it returns.
* remove unnecessary includes from src/port/pg_numa.c, adding
unnecessary dependencies (src/port should be suitable for frontent).
These were either leftovers or unnecessary thanks to the other changes
in this commit.
This eliminates unnecessary dependencies on backend symbols, which we
don't want in src/port.
Reported-by: Kirill Reshke <reshkekirill@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
https://postgr.es/m/CALdSSPi5fj0a7UG7Fmw2cUD1uWuckU_e8dJ+6x-bJEokcSXzqA@mail.gmail.com
Change MyCancelKeyLength's type from uint8 to int. While it always
fits in a uint8, plain int is less surprising, as there's no
particular reason for it to be uint8.
Fix one ProcSignalInit caller that passed 'false' instead of NULL for
the pointer argument.
Author: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://www.postgresql.org/message-id/61be9e31-7b7d-49d5-bc11-721800d89d64@eisentraut.org
These examples fail to account for join clauses generated by
EquivalenceClasses, but since we haven't mentioned EquivalenceClasses
yet it seems like it'd just add confusion to make them fully accurate.
Instead, parenthetically note that they're oversimplified.
Reported-by: Zeyuan Hu <ferrishu3886@gmail.com>
Co-authored-by: David Rowley <dgrowleyml@gmail.com>
Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CACvHWmYFo+60yMqKJajDDvKN5EM41YHrCT3oxukwXmGAqpWvyw@mail.gmail.com
The issue happens when building conflict information during apply of
INSERT or UPDATE operations that violate unique constraints on leaf
partitions.
The problem was introduced in commit 9ff68679b5, which removed the
redundant calls to ExecOpenIndices/ExecCloseIndices. The previous code was
relying on the redundant ExecOpenIndices call in
apply_handle_tuple_routing() to build the index information required for
unique key conflict detection.
The fix is to delay building the index information until a conflict is
detected instead of relying on ExecOpenIndices to do the same. The
additional benefit of this approach is that it avoids building index
information when there is no conflict.
Author: Hou Zhijie <houzj.fnst@fujitsu.com>
Reviewed-by:Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/TYAPR01MB57244ADA33DDA57119B9D26494A62@TYAPR01MB5724.jpnprd01.prod.outlook.com
It can be set to either COPY (the default) or CLONE if the system
supports it. CLONE causes callers of copydir(), currently CREATE
DATABASE ... STRATEGY=FILE_COPY and ALTER DATABASE ... SET TABLESPACE =
..., to use copy_file_range (Linux, FreeBSD) or copyfile (macOS) to copy
files instead of a read-write loop over the contents.
CLONE gives the kernel the opportunity to share block ranges on
copy-on-write file systems and push copying down to storage on others,
depending on configuration. On some systems CLONE can be used to clone
large databases quickly with CREATE DATABASE ... TEMPLATE=source
STRATEGY=FILE_COPY.
Other operating systems could be supported; patches welcome.
Co-authored-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Ranier Vilela <ranier.vf@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKGLM%2Bt%2BSwBU-cHeMUXJCOgBxSHLGZutV5zCwY4qrCcE02w%40mail.gmail.com
This adds a function for retrieving memory context statistics
and information from backends as well as auxiliary processes.
The intended usecase is cluster debugging when under memory
pressure or unanticipated memory usage characteristics.
When calling the function it sends a signal to the specified
process to submit statistics regarding its memory contexts
into dynamic shared memory. Each memory context is returned
in detail, followed by a cumulative total in case the number
of contexts exceed the max allocated amount of shared memory.
Each process is limited to use at most 1Mb memory for this.
A summary can also be explicitly requested by the user, this
will return the TopMemoryContext and a cumulative total of
all lower contexts.
In order to not block on busy processes the caller specifies
the number of seconds during which to retry before timing out.
In the case where no statistics are published within the set
timeout, the last known statistics are returned, or NULL if
no previously published statistics exist. This allows dash-
board type queries to continually publish even if the target
process is temporarily congested. Context records contain a
timestamp to indicate when they were submitted.
Author: Rahila Syed <rahilasyed90@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Reviewed-by: Atsushi Torikoshi <torikoshia@oss.nttdata.com>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
Discussion: https://postgr.es/m/CAH2L28v8mc9HDt8QoSJ8TRmKau_8FM_HKS41NeO9-6ZAkuZKXw@mail.gmail.com
Before, BAS_BULKREAD was always of size 256kB. With the default
io_combine_limit of 16, that only allowed 1-2 IOs to be in flight -
insufficient even on very low latency storage.
We don't just want to increase the size to a much larger hardcoded value, as
very large rings (10s of MBs of of buffers), appear to have negative
performance effects when reading in data that the OS has cached (but not when
actually needing to do IO).
To address this, increase the size of BAS_BULKREAD to allow for
io_combine_limit * effective_io_concurrency buffers getting read in. To
prevent the ring being much larger than useful, limit the increased size with
GetPinLimit().
The formula outlined above keeps the ring size to sizes for which we have not
observed performance regressions, unless very large effective_io_concurrency
values are used together with large shared_buffers setting.
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/lqwghabtu2ak4wknzycufqjm5ijnxhb4k73vzphlt2a3wsemcd@gtftg44kdim6
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah@brqs62irg4dt
In addition to the added functions, the pg_buffercache_evict() function now
shows whether the buffer was flushed.
pg_buffercache_evict_relation(): Evicts all shared buffers in a
relation at once.
pg_buffercache_evict_all(): Evicts all shared buffers at once.
Both functions provide mechanism to evict multiple shared buffers at
once. They are designed to address the inefficiency of repeatedly calling
pg_buffercache_evict() for each individual buffer, which can be time-consuming
when dealing with large shared buffer pools. (e.g., ~477ms vs. ~2576ms for
16GB of fully populated shared buffers).
These functions are intended for developer testing and debugging
purposes and are available to superusers only.
Minimal tests for the new functions are included. Also, there was no test for
pg_buffercache_evict(), test for this added too.
No new extension version is needed, as it was already increased this release
by ba2a3c2302.
Author: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Aidar Imamov <a.imamov@postgrespro.ru>
Reviewed-by: Joseph Koshakow <koshy44@gmail.com>
Discussion: https://postgr.es/m/CAN55FZ0h_YoSqqutxV6DES1RW8ig6wcA8CR9rJk358YRMxZFmw%40mail.gmail.com
When planning queries to partitioned tables, we clone all
EquivalenceMembers belonging to the partitioned table into em_is_child
EquivalenceMembers for each non-pruned partition. For partitioned tables
with large numbers of partitions, this meant the ec_members list could
become large and code searching that list would become slow. Effectively,
the more partitions which were present, the more searches needed to be
performed for operations such as find_ec_member_matching_expr() during
create_plan() and the more partitions present, the longer these searches
would take, i.e., a quadratic slowdown.
To fix this, here we adjust how we store EquivalenceMembers for
em_is_child members. Instead of storing these directly in ec_members,
these are now stored in a new array of Lists in the EquivalenceClass,
which is indexed by the relid. When we want to find EquivalenceMembers
belonging to a certain child relation, we can narrow the search to the
array element for that relation.
To make EquivalenceMember lookup easier and to reduce the amount of code
change, this commit provides a pair of functions to allow iteration over
the EquivalenceMembers of an EC which also handles finding the child
members, if required. Callers that never need to look at child members
can remain using the foreach loop over ec_members, which will now often
be faster due to only parent-level members being stored there.
The actual performance increases here are highly dependent on the number
of partitions and the query being planned. Performance increases can be
visible with as few as 8 partitions, but the speedup is marginal for
such low numbers of partitions. The speedups become much more visible
with a few dozen to hundreds of partitions. With some tested queries
using 56 partitions, the planner was around 3x faster than before. For
use cases with thousands of partitions, these are likely to become
significantly faster. Some testing has shown planner speedups of 60x or
more with 8192 partitions.
Author: Yuya Watari <watari.yuya@gmail.com>
Co-authored-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andrey Lepikhov <a.lepikhov@postgrespro.ru>
Reviewed-by: Alena Rybakina <lena.ribackina@yandex.ru>
Reviewed-by: Dmitry Dolgov <9erthalion6@gmail.com>
Reviewed-by: Amit Langote <amitlangote09@gmail.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Tested-by: Thom Brown <thom@linux.com>
Tested-by: newtglobal postgresql_contributors <postgresql_contributors@newtglobalcorp.com>
Discussion: https://postgr.es/m/CAJ2pMkZNCgoUKSE%2B_5LthD%2BKbXKvq6h2hQN8Esxpxd%2Bcxmgomg%40mail.gmail.com
Some tests try to invalidate logical slots on the standby server by
running VACUUM on the primary. The problem is that xl_running_xacts was
getting generated and replayed before the VACUUM command, leading to the
advancement of the active slot's catalog_xmin. Due to this, active slots
were not getting invalidated, leading to test failures.
We fix it by skipping the generation of xl_running_xacts for the required
tests with the help of injection points. As the required interface for
injection points was not present in back branches, we fixed the failing
tests in them by disallowing the slot to become active for the required
cases (where rows_removed conflict could be generated).
Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 16, where it was introduced
Discussion: https://postgr.es/m/Z6oQXc8LmiTLfwLA@ip-10-97-1-34.eu-west-3.compute.internal
A PG 17 optimization allowed columns with NOT NULL constraints to skip
table scans for IS NULL queries, and to skip IS NOT NULL checks for IS
NOT NULL queries. This didn't work for domain types, since domain types
don't follow the IS NULL/IS NOT NULL constraint logic. To fix, disable
this optimization for domains for PG 17+.
Reported-by: Jan Behrens
Diagnosed-by: Tom Lane
Discussion: https://postgr.es/m/Z37p0paENWWUarj-@momjian.us
Backpatch-through: 17
WAL senders do not flush their statistics until they exit, limiting the
monitoring possible for live processes. This is penalizing when WAL
senders are running for a long time, like in streaming or logical
replication setups, because it is not possible to know the amount of IO
they generate while running.
This commit makes WAL senders more aggressive with their statistics
flush, using an internal of 1 second, with the flush timing calculated
based on the existing GetCurrentTimestamp() done before the sleeps done
to wait for some activity. Note that the sleep done for logical and
physical WAL senders happens in two different code paths, so the stats
flushes need to happen in these two places.
One test is added for the physical WAL sender case, and one for the
logical WAL sender case. This can be done in a stable fashion by
relying on the WAL generated by the TAP tests in combination with a
stats reset while a server is running, but only on HEAD as WAL data has
been added to pg_stat_io in a051e71e28.
This issue exists since a9c70b46db and the introduction of pg_stat_io,
so backpatch down to v16.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Reviewed-by: Xuneng Zhou <xunengzhou@gmail.com>
Discussion: https://postgr.es/m/Z73IsKBceoVd4t55@ip-10-97-1-34.eu-west-3.compute.internal
Backpatch-through: 16
Introduce new pg_shmem_alloctions_numa view with information about how
shared memory is distributed across NUMA nodes. For each shared memory
segment, the view returns one row for each NUMA node backing it, with
the total amount of memory allocated from that node.
The view may be relatively expensive, especially when executed for the
first time in a backend, as it has to touch all memory pages to get
reliable information about the NUMA node. This may also force allocation
of the shared memory.
Unlike pg_shmem_allocations, the view does not show anonymous shared
memory allocations. It also does not show memory allocated using the
dynamic shared memory infrastructure.
Author: Jakub Wartak <jakub.wartak@enterprisedb.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CAKZiRmxh6KWo0aqRqvmcoaX2jUxZYb4kGp3N%3Dq1w%2BDiH-696Xw%40mail.gmail.com
Add basic NUMA awareness routines, using a minimal src/port/pg_numa.c
portability wrapper and an optional build dependency, enabled by
--with-libnuma configure option. For now this is Linux-only, other
platforms may be supported later.
A built-in SQL function pg_numa_available() allows checking NUMA
support, i.e. that the server was built/linked with the NUMA library.
The main function introduced is pg_numa_query_pages(), which allows
determining the NUMA node for individual memory pages. Internally the
function uses move_pages(2) syscall, as it allows batching, and is more
efficient than get_mempolicy(2).
Author: Jakub Wartak <jakub.wartak@enterprisedb.com>
Co-authored-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CAKZiRmxh6KWo0aqRqvmcoaX2jUxZYb4kGp3N%3Dq1w%2BDiH-696Xw%40mail.gmail.com
In some edge cases valgrind flags issues with the memory referenced by
IOs. All of the cases addressed in this change are false positives.
Most of the false positives are caused by UnpinBuffer[NoOwner] marking buffer
data as inaccessible. This happens even though the AIO subsystem still holds a
pin. That's good, there shouldn't be accesses to the buffer outside of AIO
related code until it is pinned by "user" code again. But it requires some
explicit work - if the buffer is not pinned by the current backend, we need to
explicitly mark the buffer data accessible/inaccessible while executing
completion callbacks.
That however causes a cascading issue in IO workers: After the completion
callbacks for a buffer is executed, the page is marked as inaccessible. If
subsequently the same worker is executing IO targeting the same buffer, we
would get an error, as the memory is still marked inaccessible. To avoid that,
we need to explicitly mark the memory as accessible in IO workers.
Another issue is that IO executed in workers or via io_uring will not mark
memory as DEFINED. In the case of workers that is because valgrind does not
track memory definedness across processes. For io_uring that is because
valgrind does not understand io_uring, and therefore its IOs never mark memory
as defined, whether the completions are processed in the defining process or
in another context. It's not entirely clear how to best solve that. The
current user of AIO is not affected, as it explicitly marks buffers as DEFINED
& NOACCESS anyway. Defer solving this issue until we have a user with
different needs.
Per buildfarm animal skink.
Reviewed-by: Noah Misch <noah@leadboat.com>
Co-authored-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/3pd4322mogfmdd5nln3zphdwhtmq3rzdldqjwb2sfqzcgs22lf@ok2gletdaoe6
This mirrors 1e0dfd166b (+ 46ef520b95), for temporary table buffers. This
is mainly interesting right now because the AIO work currently triggers
spurious valgrind errors, and the fix for that is cleaner if temp buffers
behave the same as shared buffers.
This requires one change beyond the annotations themselves, namely to pin
local buffers while writing them out in FlushRelationBuffers().
Reviewed-by: Noah Misch <noah@leadboat.com>
Co-authored-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/3pd4322mogfmdd5nln3zphdwhtmq3rzdldqjwb2sfqzcgs22lf@ok2gletdaoe6
The list of transform objects that a function should use is specified
in CREATE FUNCTION's TRANSFORM clause, and then represented indirectly
in pg_proc.protrftypes. However, ProcedureCreate completely ignored
that for purposes of constructing pg_depend entries, and instead made
the function depend on any transforms that exist for its parameter or
return data types. This is bad in both directions: the function could
be made dependent on a transform it does not actually use, or it
could try to use a transform that's since been dropped. (The latter
scenario would require use of a transform that's not for any of the
parameter or return types, but that seems legit for cases where the
function performs SQL operations internally.)
To fix, pass in the list of transform objects that CreateFunction
identified, and build pg_depend entries from that not from the
parameter/return types. This results in changes in the expected
test outputs in contrib/bool_plperl, which I guess are due to
different ordering of pg_depend entries -- that test case is
surely not exercising either of the problem scenarios.
This fix is not back-patchable as-is: changing the signature of
ProcedureCreate seems too risky in stable branches. We could
do something like making ProcedureCreate a wrapper around
ProcedureCreateExt or so. However, I'm more inclined to do
nothing in the back branches. We had no field complaints up to
now, so the hazards don't seem to be a big issue in practice.
And we couldn't do anything about existing pg_depend entries,
so a back-patched fix would result in a mishmash of dependencies
created according to different rules. That cure could be worse
than the disease, perhaps.
I bumped catversion just to lay down a marker that the expected
contents of pg_depend are a bit different than before.
Reported-by: Chapman Flack <jcflack@acm.org>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/3112950.1743984111@sss.pgh.pa.us
This allows them to be added without scanning the table, and validating
them afterwards without holding access exclusive lock on the table after
any violating rows have been deleted or fixed.
Doing ALTER TABLE ... SET NOT NULL for a column that has an invalid
not-null constraint validates that constraint. ALTER TABLE .. VALIDATE
CONSTRAINT is also supported. There are various checks on whether an
invalid constraint is allowed in a child table when the parent table has
a valid constraint; this should match what we do for enforced/not
enforced constraints.
pg_attribute.attnotnull is now only an indicator for whether a not-null
constraint exists for the column; whether it's valid or invalid must be
queried in pg_constraint. Applications can continue to query
pg_attribute.attnotnull as before, but now it's possible that NULL rows
are present in the column even when that's set to true.
For backend internal purposes, we cache the nullability status in
CompactAttribute->attnullability that each tuple descriptor carries
(replacing CompactAttribute.attnotnull, which was a mirror of
Form_pg_attribute.attnotnull). During the initial tuple descriptor
creation, based on the pg_attribute scan, we set this to UNRESTRICTED if
pg_attribute.attnotnull is false, or to UNKNOWN if it's true; then we
update the latter to VALID or INVALID depending on the pg_constraint
scan. This flag is also copied when tupledescs are copied.
Comparing tuple descs for equality must also compare the
CompactAttribute.attnullability flag and return false in case of a
mismatch.
pg_dump deals with these constraints by storing the OIDs of invalid
not-null constraints in a separate array, and running a query to obtain
their properties. The regular table creation SQL omits them entirely.
They are then dealt with in the same way as "separate" CHECK
constraints, and dumped after the data has been loaded. Because no
additional pg_dump infrastructure was required, we don't bump its
version number.
I decided not to bump catversion either, because the old catalog state
works perfectly in the new world. (Trying to run with new catalog state
and the old server version would likely run into issues, however.)
System catalogs do not support invalid not-null constraints (because
commit 14e87ffa5c didn't allow them to have pg_constraint rows
anyway.)
Author: Rushabh Lathia <rushabh.lathia@gmail.com>
Author: Jian He <jian.universality@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Tested-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: https://postgr.es/m/CAGPqQf0KitkNack4F5CFkFi-9Dqvp29Ro=EpcWt=4_hs-Rt+bQ@mail.gmail.com
This escape shows the numeric server IP address that the client
has connected to. Unix-socket connections will show "[local]".
Non-client processes (e.g. background processes) will show "[none]".
We expect that this option will be of interest to only a fairly
small number of users. Therefore the implementation is optimized
for the case where it's not used (that is, we don't do the string
conversion until we have to), and we've not added the field to
csvlog or jsonlog formats.
Author: Greg Sabino Mullane <htamfids@gmail.com>
Reviewed-by: Cary Huang <cary.huang@highgo.ca>
Reviewed-by: David Steele <david@pgmasters.net>
Reviewed-by: Jim Jones <jim.jones@uni-muenster.de>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAKAnmmK-U+UicE-qbNU23K--Q5XTLdM6bj+gbkZBZkjyjrd3Ow@mail.gmail.com
If the limit returned by GetAdditionalPinLimit() is large, the buffer_limit
variable in read_stream_start_pending_read() can overflow. While the code is
careful to limit buffer_limit PG_INT16_MAX, we subsequently add the number of
forwarded buffers.
The overflow can lead to assertion failures, crashes or wrong query results
when using large shared buffers.
It seems easier to avoid this if we make the buffer_limit variable an int,
instead of an int16. Do so, and clamp buffer_limit after adding the number of
forwarded buffers.
It's possible we might want to address this and related issues more widely by
changing to int instead of int16 more widely, but since the consequences of
this bug can be confusing, it seems better to fix it now.
This bug was introduced in ed0b87caac.
Discussion: https://postgr.es/m/ewvz3cbtlhrwqk7h6ca6cctiqh7r64ol3pzb3iyjycn2r5nxk5@tnhw3a5zatlr
fc069a3a63 implements Self-Join Elimination (SJE) and provides a new GUC
variable: enable_self_join_elimination. This new GUC variable was marked
as GUC_NOT_IN_SAMPLE. However, enable_self_join_elimination is documented
and is not different from any other enable_* GUCs. Thus, remove
GUC_NOT_IN_SAMPLE from it and add it to the postgresql.conf.sample.
Discussion: https://postgr.es/m/CAPpHfdsqMTEsmxk3aQwt6xPz%2BKpUELO%3D6fzmER9ZRGrbs4uMfA%40mail.gmail.com
Author: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
palloc() is invoked with a specific formula for its allocation size in
quote_literal_cstr(). This wastes some memory, but the size is large
enough to cover even the worst-case scenarios.
No explanations were given about the reasons behind these numbers. This
commit adds more documentation about all that.
Author: Steve Chavez <steve@supabase.io>
Discussion: https://postgr.es/m/CAGRrpzZ9bToRWS+fAnjxDJrxwZN1QcJ-y1Pn2yg=Hst6rydLtw@mail.gmail.com
stats_fetch_consistency set to "snapshot" causes the backend entry
"beentry" retrieved by pgstat_get_beentry_by_proc_number() to be reset
at the beginning of pgstat_fetch_stat_backend() when fetching the
backend pgstats entry. As coded, "beentry" was being accessed after
being freed. This commit moves all the accesses to "beentry" to happen
before calling pgstat_fetch_stat_backend(), fixing the problem.
This problem could be reached by calling the SQL functions
pg_stat_get_backend_io() or pg_stat_get_backend_wal().
Issue caught by valgrind.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/f1788cc0-253a-4a3a-aee0-1b8ab9538736@gmail.com
The XLOG_CONTROL_FILE macro (defined in access/xlog_internal.h)
represents the control file name. While some parts of the codebase already
use this macro, others previously hardcoded the file name as a string.
This commit replaces those hardcoded strings with the macro,
ensuring consistent usage throughout the code. This makes future
maintenance easier and improves searchability, for example when
grepping for control file usage.
Author: Anton A. Melnikov <a.melnikov@postgrespro.ru>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-by: Masao Fujii <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/0841ec77-47e5-452a-adb4-c6fa55d605fc@postgrespro.ru
PgAioResult.result is never accessed in the relevant path, but coverity
complains about an uninitialized access anyway. So just zero-initialize the
whole thing. While at it, reduce the scope of the variable.
Reported-by: Ranier Vilela <ranier.vf@gmail.com>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/CAEudQApsKqd-s+fsUQ0OmxJAMHmBSXxrAz3dCs+uvqb3iRtjSw@mail.gmail.com
This should silence Coverity's complaints about the result being
sometimes ignored.
I'm inclined to think that these routines are simply misdesigned,
because sometimes it's okay to ignore the result and sometimes it
isn't, and we have no way to enforce the latter. But for now
I just added a comment.
There were several places in ordering-related planning where a
requirement for btree was hardcoded but an amcanorder index could
suffice. This fixes that. We just need to do the necessary mapping
between strategy numbers and compare types and adjust some related
APIs so that this works independent of btree strategy numbers. For
instance, non-btree amcanorder indexes can now be used to support
sorting and merge joins. Also, predtest.c works independent of btree
strategy numbers now.
To avoid performance regressions, some details on btree and other
built-in index types are still hardcoded as shortcuts, but other index
types now have access to the same features by providing the required
flags and callbacks.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Co-authored-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
makeDependencyGraphWalker thought that only SelectStmt nodes could
contain a WithClause. Which was true in our original implementation
of WITH, but astonishingly we missed updating this code when we added
the ability to attach WITH to INSERT/UPDATE/DELETE (and later MERGE).
Moreover, since it was coded to deliberately block recursion to a
WithClause, even updating raw_expression_tree_walker didn't save it.
The upshot of this was that we didn't see references to outer CTE
names appearing within an inner WITH, and would neither complain about
disallowed recursion nor account for such references when sorting CTEs
into a usable order. The lack of complaints about this is perhaps not
so surprising, because typical usage of WITH wouldn't hit either case.
Still, it's pretty broken; failing to detect recursion here leads to
assert failures or worse later on.
Fix by factoring out the processing of sub-WITHs into a new function
WalkInnerWith, and invoking that for all the statement types that
can have WITH.
Bug: #18878
Reported-by: Yu Liang <luy70@psu.edu>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18878-a26fa5ab6be2f2cf@postgresql.org
Backpatch-through: 13
transformJsonArrayQueryConstructor() applied transformStmt() to
the same subquery tree twice. While this causes no issue in many
cases, there are some where it causes a coredump, thanks to the
parser's habit of scribbling on its input.
Fix by making a copy before the first transformation (compare
0f43083d1). This is quite brute-force, but then so is the
whole business of transforming the input twice. Per discussion
in the bug thread, this implementation of json_array() parsing
should be replaced completely. But that will take some work
and will surely not be back-patchable, so for the moment let's
take the easy way out.
Oversight in 7081ac46a. Back-patch to v16 where that came in.
Bug: #18877
Reported-by: Yu Liang <luy70@psu.edu>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18877-c3c3ad75845833bb@postgresql.org
Backpatch-through: 16
Since v15 we've had an option to apply a foreign key constraint's
ON DELETE SET DEFAULT or SET NULL action to just some of the
referencing columns. There was not a check for duplicate entries in
the list of columns-to-set, though. That caused a potential memory
stomp in CreateConstraintEntry(), which incautiously assumed that
the list of columns-to-set couldn't be longer than the number of key
columns. Even after fixing that, the case doesn't work because you
get an error like "multiple assignments to same column" from the SQL
command that is generated to do the update.
We could either raise an error for duplicate columns or silently
suppress the dups, and after a bit of thought I chose to do the
latter. This is motivated by the fact that duplicates in the FK
column list are legal, so it's not real clear why duplicates
in the columns-to-set list shouldn't be. Of course there's no
need to actually set the column more than once.
I left in the fix in CreateConstraintEntry() too, just because
it didn't seem like such low-level code ought to be making
assumptions about what it's handed.
Bug: #18879
Reported-by: Yu Liang <luy70@psu.edu>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18879-259fc59d072bd4d7@postgresql.org
Backpatch-through: 15
This is yet another bit of fallout from the fact that backend/parser
(like other code) feels free to scribble on the parse tree it's
handed. In this case that resulted in modifying the
relatively-short-lived copy in the cached function's source_list.
That would be fine since we only need each source_list tree once
... except that if the parser fails after making some changes,
the function cache entry remains as-is and will still be there
if the user tries to execute the function again. Then we have
problems because we're feeding a non-pristine tree to the parser.
The most expedient fix is a quick copyObject(). I considered
other answers like somehow marking the cache entry invalid
temporarily, but that would add complexity and I'm not sure
it's worth it. In typical scenarios we'd only do this once
per function query per session.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/6d442183-102c-498a-81d1-eeeb086cdc5a@gmail.com
Transform low_compare and high_compare nbtree skip array inequalities
(with opclasses that offer skip support) in such a way as to allow
_bt_first to consistently apply later keys when it descends the tree.
This can lower the number of index searches for multi-column scans that
use a ">" key on one of the index's prefix columns (or use a "<" key,
when scanning backwards) when it precedes some later lower-order key.
For example, an index qual "WHERE a > 5 AND b = 2" will now be converted
to "WHERE a >= 6 AND b = 2" by a new preprocessing step that takes place
after low_compare and high_compare have been finalized. That way, the
initial call to _bt_first can use "WHERE a >= 6 AND b = 2" to find an
initial position, rather than just using "WHERE a > 5" -- "b = 2" can be
applied during every _bt_first call. There's a decent chance that this
will allow such a scan to avoid the extra search that might otherwise be
needed to determine the lowest "a" value still satisfying "WHERE a > 5".
The transformation process can only lower the total number of index
pages read when the use of a more restrictive set of initial positioning
keys in _bt_first actually allows the scan to land on some later leaf
page directly, relative to the unoptimized case (or on an earlier leaf
page directly, when scanning backwards). But the savings can really add
up in cases where an affected skip array comes after some other array.
For example, a scan indexqual "WHERE x IN (1, 2, 3) AND y > 5 AND z = 2"
can save as many as 3 _bt_first calls by applying the new transformation
to its "y" array (up to 1 extra search can be avoided per "x" element).
Follow-up to commit 92fe23d9, which added nbtree skip scan.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/CAH2-Wz=FJ78K3WsF3iWNxWnUCY9f=Jdg3QPxaXE=uYUbmuRz5Q@mail.gmail.com
Don't allow nbtree scans with skip arrays to end any primitive scan on
its first leaf page without giving some consideration to how many times
the scan's arrays advanced while changing at least one skip array
(though continue not caring about the number of array advancements that
only affected SAOP arrays, even during skip scans with SAOP arrays).
Now when a scan performs more than 3 such array advancements in the
course of reading a single leaf page, it is taken as a signal that the
next page is unlikely to be skippable. We'll therefore continue the
ongoing primitive index scan, at least until we can perform a recheck
against the next page's finaltup.
Testing has shown that this new heuristic occasionally makes all the
difference with skip scans that were expected to rely on the "passed
first page" heuristic added by commit 9a2e2a28. Without it, there is a
remaining risk that certain kinds of skip scans will never quite manage
to clear the initial hurdle of performing a primitive scan that lasts
beyond its first leaf page (or that such a skip scan will only clear
that initial hurdle when it has already wasted noticeably-many cycles
due to inefficient primitive scan scheduling).
Follow-up to commits 92fe23d9 and 9a2e2a28.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/CAH2-Wz=RVdG3zWytFWBsyW7fWH7zveFvTHed5JKEsuTT0RCO_A@mail.gmail.com
Postgres 17 commit e0b1ee17 added two complementary optimizations to
nbtree: the "prechecked" and "firstmatch" optimizations. _bt_readpage
was made to avoid needlessly evaluating keys that are guaranteed to be
satisfied by applying page-level context. "prechecked" did this for
keys required in the current scan direction, while "firstmatch" did it
for keys required in the opposite-to-scan direction only.
The "prechecked" design had a number of notable issues. It didn't
account for the fact that an = array scan key's sk_argument field might
need to advance at the point of the page precheck (it didn't check the
precheck tuple against the key's array, only the key's sk_argument,
which needlessly made it ineffective in cases involving stepping to a
page having advanced the scan's arrays using a truncated high key).
"prechecked" was also completely ineffective when only one scan key
wasn't guaranteed to be satisfied by every tuple (it didn't recognize
that it was still safe to avoid evaluating other, earlier keys).
The "firstmatch" optimization had similar limitations. It could only be
applied after _bt_readpage found its first matching tuple, regardless of
why any earlier tuples failed to satisfy the scan's index quals. This
allowed unsatisfied non-required scan keys to impede the optimization.
Replace both optimizations with a new optimization, without any of these
limitations: the "startikey" optimization. Affected _bt_readpage calls
generate a page-level key offset ("startikey"), that their _bt_checkkeys
calls can then start at. This is an offset to the first key that isn't
known to be satisfied by every tuple on the page.
Although this is independently useful work, its main goal is to avoid
performance regressions with index scans that use skip arrays, but still
never manage to skip over irrelevant leaf pages. We must avoid wasting
CPU cycles on overly granular skip array maintenance in these cases.
The new "startikey" optimization helps with this by selectively
disabling array maintenance for the duration of a _bt_readpage call.
This has no lasting consequences for the scan's array keys (they'll
still reliably track the scan's progress through the index's key space
whenever the scan is "between pages").
Skip scan adds skip arrays during preprocessing using simple, static
rules, and decides how best to navigate/apply the scan's skip arrays
dynamically, at runtime. The "startikey" optimization enables this
approach. As a result of all this, the planner doesn't need to generate
distinct, competing index paths (one path for skip scan, another for an
equivalent traditional full index scan). The overall effect is to make
scan runtime close to optimal, even when the planner works off an
incorrect cardinality estimate. Scans will also perform well given a
skipped column with data skew: individual groups of pages with many
distinct values (in respect of a skipped column) can be read about as
efficiently as before -- without the scan being forced to give up on
skipping over other groups of pages that are provably irrelevant.
Many scans that cannot possibly skip will still benefit from the use of
skip arrays, since they'll allow the "startikey" optimization to be as
effective as possible (by allowing preprocessing to mark all the scan's
keys as required). A scan that uses a skip array on "a" for a qual
"WHERE a BETWEEN 0 AND 1_000_000 AND b = 42" is often much faster now,
even when every tuple read by the scan has its own distinct "a" value.
However, there are still some remaining regressions, affecting certain
trickier cases.
Scans whose index quals have several range skip arrays, each on some
high cardinality column, can still be slower than they were before the
introduction of skip scan -- even with the new "startikey" optimization.
There are also known regressions affecting very selective index scans
that use a skip array. The underlying issue with such selective scans
is that they never get as far as reading a second leaf page, and so will
never get a chance to consider applying the "startikey" optimization.
In principle, all regressions could be avoided by teaching preprocessing
to not add skip arrays whenever they aren't expected to help, but it
seems best to err on the side of robust performance.
Follow-up to commit 92fe23d9, which added nbtree skip scan.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Reviewed-By: Masahiro Ikeda <ikedamsh@oss.nttdata.com>
Reviewed-By: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/CAH2-Wz=Y93jf5WjoOsN=xvqpMjRy-bxCE037bVFi-EasrpeUJA@mail.gmail.com
Discussion: https://postgr.es/m/CAH2-WznWDK45JfNPNvDxh6RQy-TaCwULaM5u5ALMXbjLBMcugQ@mail.gmail.com
Teach nbtree multi-column index scans to opportunistically skip over
irrelevant sections of the index given a query with no "=" conditions on
one or more prefix index columns. When nbtree is passed input scan keys
derived from a predicate "WHERE b = 5", new nbtree preprocessing steps
output "WHERE a = ANY(<every possible 'a' value>) AND b = 5" scan keys.
That is, preprocessing generates a "skip array" (and an output scan key)
for the omitted prefix column "a", which makes it safe to mark the scan
key on "b" as required to continue the scan. The scan is therefore able
to repeatedly reposition itself by applying both the "a" and "b" keys.
A skip array has "elements" that are generated procedurally and on
demand, but otherwise works just like a regular ScalarArrayOp array.
Preprocessing can freely add a skip array before or after any input
ScalarArrayOp arrays. Index scans with a skip array decide when and
where to reposition the scan using the same approach as any other scan
with array keys. This design builds on the design for array advancement
and primitive scan scheduling added to Postgres 17 by commit 5bf748b8.
Testing has shown that skip scans of an index with a low cardinality
skipped prefix column can be multiple orders of magnitude faster than an
equivalent full index scan (or sequential scan). In general, the
cardinality of the scan's skipped column(s) limits the number of leaf
pages that can be skipped over.
The core B-Tree operator classes on most discrete types generate their
array elements with the help of their own custom skip support routine.
This infrastructure gives nbtree a way to generate the next required
array element by incrementing (or decrementing) the current array value.
It can reduce the number of index descents in cases where the next
possible indexable value frequently turns out to be the next value
stored in the index. Opclasses that lack a skip support routine fall
back on having nbtree "increment" (or "decrement") a skip array's
current element by setting the NEXT (or PRIOR) scan key flag, without
directly changing the scan key's sk_argument. These sentinel values
behave just like any other value from an array -- though they can never
locate equal index tuples (they can only locate the next group of index
tuples containing the next set of non-sentinel values that the scan's
arrays need to advance to).
A skip array's range is constrained by "contradictory" inequality keys.
For example, a skip array on "x" will only generate the values 1 and 2
given a qual such as "WHERE x BETWEEN 1 AND 2 AND y = 66". Such a skip
array qual usually has near-identical performance characteristics to a
comparable SAOP qual "WHERE x = ANY('{1, 2}') AND y = 66". However,
improved performance isn't guaranteed. Much depends on physical index
characteristics.
B-Tree preprocessing is optimistic about skipping working out: it
applies static, generic rules when determining where to generate skip
arrays, which assumes that the runtime overhead of maintaining skip
arrays will pay for itself -- or lead to only a modest performance loss.
As things stand, these assumptions are much too optimistic: skip array
maintenance will lead to unacceptable regressions with unsympathetic
queries (queries whose scan can't skip over many irrelevant leaf pages).
An upcoming commit will address the problems in this area by enhancing
_bt_readpage's approach to saving cycles on scan key evaluation, making
it work in a way that directly considers the needs of = array keys
(particularly = skip array keys).
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Masahiro Ikeda <masahiro.ikeda@nttdata.com>
Reviewed-By: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Reviewed-By: Matthias van de Meent <boekewurm+postgres@gmail.com>
Reviewed-By: Tomas Vondra <tomas@vondra.me>
Reviewed-By: Aleksander Alekseev <aleksander@timescale.com>
Reviewed-By: Alena Rybakina <a.rybakina@postgrespro.ru>
Discussion: https://postgr.es/m/CAH2-Wzmn1YsLzOGgjAQZdn1STSG_y8qP__vggTaPAYXJP+G4bw@mail.gmail.com
This commit implements the automatic conversion of 'x IN (VALUES ...)' into
ScalarArrayOpExpr. That simplifies the query tree, eliminating the appearance
of an unnecessary join.
Since VALUES describes a relational table, and the value of such a list is
a table row, the optimizer will likely face an underestimation problem due to
the inability to estimate cardinality through MCV statistics. The cardinality
evaluation mechanism can work with the array inclusion check operation.
If the array is small enough (< 100 elements), it will perform a statistical
evaluation element by element.
We perform the transformation in the convert_ANY_sublink_to_join() if VALUES
RTE is proper and the transformation is convertible. The conversion is only
possible for operations on scalar values, not rows. Also, we currently
support the transformation only when it ends up with a constant array.
Otherwise, the evaluation of non-hashed SAOP might be slower than the
corresponding Hash Join with VALUES.
Discussion: https://postgr.es/m/0184212d-1248-4f1f-a42d-f5cb1c1976d2%40tantorlabs.com
Author: Alena Rybakina <a.rybakina@postgrespro.ru>
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Ivan Kush <ivan.kush@tantorlabs.com>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
This commit extracts the code to generate ScalarArrayOpExpr on top of the list
of expressions from match_orclause_to_indexcol() into a separate function
make_SAOP_expr(). This function was extracted to be used in optimization for
conversion of 'x IN (VALUES ...)' to 'x = ANY ...'. make_SAOP_expr() is
placed in clauses.c file as only two additional headers were needed there
compared with other places.
Discussion: https://postgr.es/m/0184212d-1248-4f1f-a42d-f5cb1c1976d2%40tantorlabs.com
Author: Alena Rybakina <a.rybakina@postgrespro.ru>
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Ivan Kush <ivan.kush@tantorlabs.com>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
Fix for commit 9ef1851685: We have to skip indexes where sortopfamily
is NULL. This takes the place of the previous btree check. Detected
by valgrind on the buildfarm.
Commit 28d3c2ddcf introduced an assertion that if the memorized
downlink location in the insertion stack isn't valid, the parent's
LSN should've changed too. Turns out that was too strict. In
gistFindCorrectParent(), if we walk right, we update the parent's
block number and clear its memorized 'downlinkoffnum'. That triggered
the assertion on next call to gistFindCorrectParent(), if the parent
needed to be split too. Relax the assertion, so that it's OK if
downlinkOffnum is InvalidOffsetNumber.
Backpatch to v13-, all supported versions. The assertion was added in
commit 28d3c2ddcf in v12.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Discussion: https://www.postgresql.org/message-id/18396-03cac9beb2f7aac3@postgresql.org
Previously, "COPY table TO" command worked only with plain tables and
did not support materialized views, even when they were populated and
had physical storage. To copy rows from materialized views,
"COPY (query) TO" command had to be used, instead.
This commit extends "COPY table TO" to support populated materialized
views directly, improving usability and performance, as "COPY table TO"
is generally faster than "COPY (query) TO". Note that copying from
unpopulated materialized views will still result in an error.
Author: jian he <jian.universality@gmail.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Reviewed-by: David G. Johnston <david.g.johnston@gmail.com>
Reviewed-by: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/CACJufxHVxnyRYy67hiPePNCPwVBMzhTQ6FaL9_Te5On9udG=yg@mail.gmail.com
This was previously not supported because the btree strategy numbers
were hardcoded. Now we can support this for any index that has the
required strategy mapping support and the required operators.
If an index scan used for get_actual_variable_range() requires
recheck, we now just ignore it instead of erroring out. With btree we
knew this couldn't happen, but now it might.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Co-authored-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
Previously, ALTER DEFAULT PRIVILEGES did not support large objects.
This meant that to grant privileges to users other than the owner,
permissions had to be manually assigned each time a large object
was created, which was inconvenient.
This commit extends ALTER DEFAULT PRIVILEGES to allow defining default
access privileges for large objects. With this change, specified privileges
will automatically apply to newly created large objects, making privilege
management more efficient.
As a side effect, this commit introduces the new keyword OBJECTS
since it's used in the syntax of ALTER DEFAULT PRIVILEGES.
Original patch by Haruka Takatsuka, with some fixes and tests by Yugo Nagata,
and rebased by Laurenz Albe.
Author: Takatsuka Haruka <harukat@sraoss.co.jp>
Co-authored-by: Yugo Nagata <nagata@sraoss.co.jp>
Co-authored-by: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: Masao Fujii <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/20240424115242.236b499b2bed5b7a27f7a418@sraoss.co.jp
This gets rid of the bespoken ProcessWalRcvInterrupts() function,
which lets walreceiver terminate at any CHECK_FOR_INTERRUPTS() call.
And it's less code anyway.
We can now use the standard libpqsrv_connect_params() libpq wrapper
from libpq-be-fe-helpers.h, removing more code. We attempted to do
that earlier already in commit 728f86fec6, but that was reverted
because it didn't call ProcessWalRcvInterrupts() and therefore didn't
react to shutdown requests. Now that ProcessWalRcvInterrupts() is
gone, it works. As stated in that commit, this also leads to
libpqwalreceiver reserving file descriptors for libpq conncetions,
which is nice.
Author: Andres Freund <andres@anarazel.de> (the earlier commit)
Author: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Yura Sokolov <y.sokolov@postgrespro.ru>
Change the PathKey struct to use CompareType to record the sort
direction instead of hardcoding btree strategy numbers. The
CompareType is then converted to the index-type-specific strategy when
the plan is created.
This reduces the number of places btree strategy numbers are
hardcoded, and it's a self-contained subset of a larger effort to
allow non-btree indexes to behave like btrees.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Co-authored-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
Derived clauses are stored in ec_derives, a List of RestrictInfos.
These clauses are later looked up by matching the left and right
EquivalenceMembers along with the clause's parent EC.
This linear search becomes expensive in queries with many joins or
partitions, where ec_derives may contain thousands of entries. In
particular, create_join_clause() can spend significant time scanning
this list.
To improve performance, introduce a hash table (ec_derives_hash) that
is built when the list reaches 32 entries -- the same threshold used
for join_rel_hash. The original list is retained alongside the hash
table to support EC merging and serialization
(_outEquivalenceClass()).
Each clause is stored in the hash table using a canonicalized key: the
EquivalenceMember with the lower memory address is placed in the key
before the one with the higher memory address. This avoids storing or
searching for both permutations of the same clause. For clauses
involving a constant EM, the key places NULL in the first slot and the
non-constant EM in the second.
The hash table is initialized using list_length(ec_derives_list) as
the size hint. simplehash internally adjusts this to the next power of
two after dividing by the fillfactor, so this typically results in at
least 64 buckets near the threshold -- avoiding immediate resizing
while adapting to the actual number of entries.
The lookup logic for derived clauses is now centralized in
ec_search_derived_clause_for_ems(), which consults the hash table when
available and falls back to the list otherwise.
The new ec_clear_derived_clauses() always frees ec_derives_list, even
though some of the original code paths that cleared the old
ec_derives field did not. This ensures consistent cleanup and avoids
leaking memory when large lists are discarded.
An assertion originally placed in find_derived_clause_for_ec_member()
is moved into ec_search_derived_clause_for_ems() so that it is
enforced consistently, regardless of whether the hash table or list is
used for lookup.
This design incorporates suggestions by David Rowley, who proposed
both the key canonicalization and the initial sizing approach to
balance memory usage and CPU efficiency.
Author: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-by: Amit Langote <amitlangote09@gmail.com>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Tested-by: Dmitry Dolgov <9erthalion6@gmail.com>
Tested-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Tested-by: Amit Langote <amitlangote09@gmail.com>
Tested-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAExHW5vZiQtWU6moszLP5iZ8gLX_ZAUbgEX0DxGLx9PGWCtqUg@mail.gmail.com
find_derived_clause_for_ec_member() searches for a previously-derived
clause that equates a non-constant EquivalenceMember to a constant.
It is only called for EquivalenceClasses with ec_has_const set, and
with a non-constant member the EquivalenceMember to search for.
The matched clause is expected to have the non-constant member on the
left-hand side and the constant EquivalenceMember on the right.
Assert that the RHS is indeed a constant, to catch violations of this
structure and enforce assumptions made by
generate_base_implied_equalities_const().
Author: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-by: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/CAExHW5scMxyFRqOFE6ODmBiW2rnVBEmeEcA-p4W_CyuEikURdA@mail.gmail.com
Previously bitmap heap scan was not AIO batchmode safe because of the
visibility map reads potentially done for the "skip fetch" optimization
(which skipped fetching tuples from the heap if the pages were all
visible and none of the columns were used in the query).
The skip fetch optimization implementation was found to have bugs and
was removed in 459e7bf8e2, so we can safely enable batchmode for
bitmap heap scans.
Several read stream users asserted that the read stream was exhausted
after looping on that very condition. It was pointed out in an a
review of an as-of-yet uncommitted read stream user [1] that this was
confusing and could lead the reader to think there was a possibility of
some kind of race condition. Remove these asserts.
[1] https://postgr.es/m/F9ACE8D0-B807-4A17-B6BD-87EF0717983D%40yesql.se
As coded, fmgr_sql() would get an assertion failure for a SQL function
that has an empty body and is declared to return some type other than
VOID. Typically you'd never get that far because fmgr_sql_validator()
would reject such a definition (I suspect that's how come I managed to
miss the bug). But if check_function_bodies is off or the function is
polymorphic, the validation check wouldn't get made.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/0fde377a-3870-4d18-946a-ce008ee5bb88@gmail.com
Previously, invalidated logical and physical replication slots could
be copied using the pg_copy_logical_replication_slot and
pg_copy_physical_replication_slot functions. Replication slots that
were invalidated for reasons other than WAL removal retained their
restart_lsn. This meant that a new slot copied from an invalidated
slot could have a restart_lsn pointing to a WAL segment that might
have already been removed.
This commit restricts the copying of invalidated replication slots.
Backpatch to v16, where slots could retain their restart_lsn when
invalidated for reasons other than WAL removal.
For v15 and earlier, this check is not required since slots can only
be invalidated due to WAL removal, and existing checks already handle
this issue.
Author: Shlok Kyal <shlok.kyal.oss@gmail.com>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Reviewed-by: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/CANhcyEU65aH0VYnLiu%3DOhNNxhnhNhwcXBeT-jvRe1OiJTo_Ayg%40mail.gmail.com
Backpatch-through: 16
The check for non-inheritable constraints is performed later, and the
same comment is included at that point.
While we're here, remove one extraneous blank line.
Author: jian he <jian.universality@gmail.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Reviewed-by: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/CACJufxETi6x86S8EkH8mRfOcm2AenoE9t1pyCFVMpU34gVhF3w@mail.gmail.com
The issue is that the transactions prepared before two-phase decoding is
enabled can fail to replicate to the subscriber after being committed on a
promoted standby following a failover. This is because the two_phase_at
field of a slot, which tracks the LSN from which two-phase decoding
starts, is not synchronized to standby servers. Without two_phase_at, the
logical decoding might incorrectly identify prepared transaction as
already replicated to the subscriber after promotion of standby server,
causing them to be skipped.
To address the issue on HEAD, the two_phase_at field of the slot is
exposed by the pg_replication_slots view and allows the slot
synchronization to copy this value to the corresponding synced slot on the
standby server.
This bug is likely to occur if the user toggles the two_phase option to
true after initial slot creation. Given that altering the two_phase option
of a replication slot is not allowed in PostgreSQL 17, this bug is less
likely to occur. We can't change the view/function definition in
backbranch so we can't push the same fix but we are brainstorming an
appropriate solution for PG17.
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/TYAPR01MB5724CC7C288535BBCEEE65DA94A72@TYAPR01MB5724.jpnprd01.prod.outlook.com
compareentry() is declared to work on WordEntryIN structs, but
tsvectorrecv() is using it in two places to work on WordEntry
structs. This is almost okay, since WordEntry is the first
field of WordEntryIN. But on machines with 8-byte pointers,
WordEntryIN will have a larger alignment spec than WordEntry,
and it's at least theoretically possible that the compiler
could generate code that depends on the larger alignment.
Given the lack of field reports, this may be just a hypothetical bug
that upsets nothing except sanitizer tools. Or it may be real on
certain hardware but nobody's tried to use tsvectorrecv() on such
hardware. In any case we should fix it, and the fix is trivial:
just change compareentry() so that it works on WordEntry without any
mention of WordEntryIN. We can also get rid of the quite-useless
intermediate function WordEntryCMP.
Bug: #18875
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18875-07a29c49c825a608@postgresql.org
Backpatch-through: 13
The optimization does not take the removal of TIDs by a concurrent vacuum into
account. The concurrent vacuum can remove dead TIDs and make pages ALL_VISIBLE
while those dead TIDs are referenced in the bitmap. This can lead to a
skip_fetch scan returning too many tuples.
It likely would be possible to implement this optimization safely, but we
don't have the necessary infrastructure in place. Nor is it clear that it's
worth building that infrastructure, given how limited the skip_fetch
optimization is.
In the backbranches we just disable the optimization by always passing
need_tuples=true to table_beginscan_bm(). We can't perform API/ABI changes in
the backbranches and we want to make the change as minimal as possible.
Author: Matthias van de Meent <boekewurm+postgres@gmail.com>
Reported-By: Konstantin Knizhnik <knizhnik@garret.ru>
Discussion: https://postgr.es/m/CAEze2Wg3gXXZTr6_rwC+s4-o2ZVFB5F985uUSgJTsECx6AmGcQ@mail.gmail.com
Backpatch-through: 13
In the historical implementation of SQL functions (if they don't get
inlined), we built plans for all the contained queries at first call
within an outer query, and then re-used those plans for the duration
of the outer query, and then forgot everything. This was not ideal,
not least because the plans could not be customized to specific values
of the function's parameters. Our plancache infrastructure seems
mature enough to be used here. That will solve both the problem with
not being able to build custom plans and the problem with not being
able to share work across successive outer queries.
Aside from those performance concerns, this change fixes a
longstanding bugaboo with SQL functions: you could not write DDL that
would affect later statements in the same function. That's mostly
still true with new-style SQL functions, since the results of parse
analysis are baked into the stored query trees (and protected by
dependency records). But for old-style SQL functions, it will now
work much as it does with PL/pgSQL functions, because we delay parse
analysis and planning of each query until we're ready to run it.
Some edge cases that require replanning are now handled better too;
see for example the new rowsecurity test, where we now detect an RLS
context change that was previously missed.
One other edge-case change that might be worthy of a release note
is that we now insist that a SQL function's result be generated
by the physically-last query within it. Previously, if the last
original query was deleted by a DO INSTEAD NOTHING rule, we'd be
willing to take the result from the preceding query instead.
This behavior was undocumented except in source-code comments,
and it seems hard to believe that anyone's relying on it.
Along the way to this feature, we needed a few infrastructure changes:
* The plancache can now take either a raw parse tree or an
analyzed-but-not-rewritten Query as the starting point for a
CachedPlanSource. If given a Query, it is caller's responsibility
that nothing will happen to invalidate that form of the query.
We use this for new-style SQL functions, where what's in pg_proc is
serialized Query(s) and we trust the dependency mechanism to disallow
DDL that would break those.
* The plancache now offers a way to invoke a post-rewrite callback
to examine/modify the rewritten parse tree when it is rebuilding
the parse trees after a cache invalidation. We need this because
SQL functions sometimes adjust the parse tree to make its output
exactly match the declared result type; if the plan gets rebuilt,
that has to be re-done.
* There is a new backend module utils/cache/funccache.c that
abstracts the idea of caching data about a specific function
usage (a particular function and set of input data types).
The code in it is moved almost verbatim from PL/pgSQL, which
has done that for a long time. We use that logic now for
SQL-language functions too, and maybe other PLs will have use
for it in the future.
Author: Alexander Pyhalov <a.pyhalov@postgrespro.ru>
Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Discussion: https://postgr.es/m/8216639.NyiUUSuA9g@aivenlaptop
For GiST, having a sortsupport function allows building the index
using the "sorted build" method, which is much faster.
For b-tree, the sortsupport routine doesn't give any new
functionality, but speeds up sorting a tiny bit. The difference is not
very significant, about 2% in cursory testing on my laptop, because
the range type comparison function has quite a lot of overhead from
detoasting. In any case, since we have the function for GiST anyway,
we might as well register it for the btree opfamily too.
Author: Bernd Helmle <mailings@oopsware.de>
Discussion: https://www.postgresql.org/message-id/64d324ce2a6d535d3f0f3baeeea7b25beff82ce4.camel@oopsware.de
Various places allocated shared memory by first allocating a small chunk
using ShmemInitStruct(), followed by ShmemAlloc() calls to allocate more
memory. Unfortunately, ShmemAlloc() does not update ShmemIndex, so this
affected pg_shmem_allocations - it only shown the initial chunk.
This commit modifies the following allocations, to allocate everything
as a single chunk, and then split it internally.
- PredXactList
- RWConflictPool
- PGPROC structures
- Fast-Path Lock Array
The fast-path lock array is allocated separately, not as a part of the
PGPROC structures allocation.
Author: Rahila Syed <rahilasyed90@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CAH2L28vHzRankszhqz7deXURxKncxfirnuW68zD7+hVAqaS5GQ@mail.gmail.com
pg_shmem_allocations tracks the memory allocated by ShmemInitStruct(),
but for shared hash tables that covered only the header and hash
directory. The remaining parts (segments and buckets) were allocated
later using ShmemAlloc(), which does not update the shmem accounting.
Thus, these allocations were not shown in pg_shmem_allocations.
This commit improves the situation by allocating all the hash table
parts at once, using a single ShmemInitStruct() call. This way the
ShmemIndex entries (and thus pg_shmem_allocations) better reflect the
proper size of the hash table.
This affects allocations for private (non-shared) hash tables too, as
the hash_create() code is shared. For non-shared tables this however
makes no practical difference.
This changes the alignment a bit. ShmemAlloc() aligns the chunks using
CACHELINEALIGN(), which means some parts (header, directory, segments)
were aligned this way. Allocating all parts as a single chunk removes
this (implicit) alignment. We've considered adding explicit alignment,
but we've decided not to - it seems to be merely a coincidence due to
using the ShmemAlloc() API, not due to necessity.
Author: Rahila Syed <rahilasyed90@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CAH2L28vHzRankszhqz7deXURxKncxfirnuW68zD7+hVAqaS5GQ@mail.gmail.com
Without this, an additional change to the same pg_attribute row
within the same command will fail. This is possible at least with
ALTER TABLE ADD COLUMN on a multiple-inheritance-pathway structure.
(Another potential hazard is that immediately-following operations
might not see the missingval.)
Introduced by 95f650674, which split the former coding that
used a single pg_attribute update to change both atthasdef and
atthasmissing/attmissingval into two updates, but missed that
this should entail two CommandCounterIncrements as well. Like
that fix, back-patch through v13.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/025a3ffa-5eff-4a88-97fb-8f583b015965@gmail.com
Backpatch-through: 13
Currently, the cancel request key is a 32-bit token, which isn't very
much entropy. If you want to cancel another session's query, you can
brute-force it. In most environments, an unauthorized cancellation of
a query isn't very serious, but it nevertheless would be nice to have
more protection from it. Hence make the key longer, to make it harder
to guess.
The longer cancellation keys are generated when using the new protocol
version 3.2. For connections using version 3.0, short 4-bytes keys are
still used.
The new longer key length is not hardcoded in the protocol anymore,
the client is expected to deal with variable length keys, up to 256
bytes. This flexibility allows e.g. a connection pooler to add more
information to the cancel key, which might be useful for finding the
connection.
Reviewed-by: Jelte Fennema-Nio <postgres@jeltef.nl>
Reviewed-by: Robert Haas <robertmhaas@gmail.com> (earlier versions)
Discussion: https://www.postgresql.org/message-id/508d0505-8b7a-4864-a681-e7e5edfe32aa@iki.fi
This expands the NOT ENFORCED constraint flag, previously only
supported for CHECK constraints (commit ca87c415e2), to foreign key
constraints.
Normally, when a foreign key constraint is created on a table, action
and check triggers are added to maintain data integrity. With this
patch, if a constraint is marked as NOT ENFORCED, integrity checks are
no longer required, making these triggers unnecessary. Consequently,
when creating a NOT ENFORCED foreign key constraint, triggers will not
be created, and the constraint will be marked as NOT VALID.
Similarly, if an existing foreign key constraint is changed to NOT
ENFORCED, the associated triggers will be dropped, and the constraint
will also be marked as NOT VALID. Conversely, if a NOT ENFORCED
foreign key constraint is changed to ENFORCED, the necessary triggers
will be created, and the will be changed to VALID by performing
necessary validation.
Since not-enforced foreign key constraints have no triggers, the
shortcut used for example in psql and pg_dump to skip looking for
foreign keys if the relation is known not to have triggers no longer
applies. (It already didn't work for partitioned tables.)
Author: Amul Sul <sulamul@gmail.com>
Reviewed-by: Joel Jacobson <joel@compiler.org>
Reviewed-by: Andrew Dunstan <andrew@dunslane.net>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: jian he <jian.universality@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-by: Isaac Morland <isaac.morland@gmail.com>
Reviewed-by: Alexandra Wang <alexandra.wang.oss@gmail.com>
Tested-by: Triveni N <triveni.n@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/CAAJ_b962c5AcYW9KUt_R_ER5qs3fUGbe4az-SP-vuwPS-w-AGA@mail.gmail.com
Allow multiple backends to initialize WAL buffers concurrently. This way
`MemSet((char *) NewPage, 0, XLOG_BLCKSZ);` can run in parallel without
taking a single LWLock in exclusive mode.
The new algorithm works as follows:
* reserve a page for initialization using XLogCtl->InitializeReserved,
* ensure the page is written out,
* once the page is initialized, try to advance XLogCtl->InitializedUpTo and
signal to waiters using XLogCtl->InitializedUpToCondVar condition
variable,
* repeat previous steps until we reserve initialization up to the target
WAL position,
* wait until concurrent initialization finishes using a
XLogCtl->InitializedUpToCondVar.
Now, multiple backends can, in parallel, concurrently reserve pages,
initialize them, and advance XLogCtl->InitializedUpTo to point to the latest
initialized page.
Author: Yura Sokolov <y.sokolov@postgrespro.ru>
Co-authored-by: Alexander Korotkov <aekorotkov@gmail.com>
Reviewed-by: Pavel Borisov <pashkin.elfe@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Tested-by: Michael Paquier <michael@paquier.xyz>
Even after reaching the minimum recovery point, if there are long-lived
write transactions with 64 subtransactions on the primary, the recovery
snapshot may not yet be ready for hot standby, delaying read-only
connections on the standby. Previously, when read-only connections were
not accepted due to this condition, the following error message was logged:
FATAL: the database system is not yet accepting connections
DETAIL: Consistent recovery state has not been yet reached.
This DETAIL message was misleading because the following message was
already logged in this case:
LOG: consistent recovery state reached
This contradiction, i.e., indicating that the recovery state was consistent
while also stating it wasn’t, caused confusion.
This commit improves the error message to better reflect the actual state:
FATAL: the database system is not yet accepting connections
DETAIL: Recovery snapshot is not yet ready for hot standby.
HINT: To enable hot standby, close write transactions with more than 64 subtransactions on the primary server.
To implement this, the commit introduces a new postmaster signal,
PMSIGNAL_RECOVERY_CONSISTENT. When the startup process reaches
a consistent recovery state, it sends this signal to the postmaster,
allowing it to correctly recognize that state.
Since this is not a clear bug, the change is applied only to the master
branch and is not back-patched.
Author: Atsushi Torikoshi <torikoshia@oss.nttdata.com>
Co-authored-by: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Yugo Nagata <nagata@sraoss.co.jp>
Discussion: https://postgr.es/m/02db8cd8e1f527a8b999b94a4bee3165@oss.nttdata.com
Push an ErrorContextCallback adding additional detail about the process
performing the I/O and the owner of the I/O when those are not the same.
For io_method worker, this adds context specifying which process owns
the I/O that the I/O worker is processing.
For io_method io_uring, this adds context only when a backend is
*completing* I/O for another backend. It specifies the pid of the owning
process.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/rdml3fpukrqnas7qc5uimtl2fyytrnu6ymc2vjf2zuflbsjuul%40hyizyjsexwmm
50e17ad28 (v14) and 29f45e299 (v15) made it so the planner could identify
IN and NOT IN clauses which have Const lists as right-hand arguments and
when an appropriate hash function is available for the data types, mark
the ScalarArrayOpExpr as hashable so the executor could execute it more
optimally by building and probing a hash table during expression
evaluation.
These commits both worked correctly when there was only a single
ScalarArrayOpExpr in the given expression being processed by the
planner, but when there were multiple, only the first was checked and any
subsequent ones were not identified, which resulted in less optimal
expression evaluation during query execution for all but the first found
ScalarArrayOpExpr.
Backpatch to 14, where 50e17ad28 was introduced.
Author: David Geier <geidav.pg@gmail.com>
Discussion: https://postgr.es/m/29a76f51-97b0-4c07-87b7-ec8e3b5345c9@gmail.com
Backpatch-through: 14
Create a function that will sort the elements of an array
according to the element type's sort order. If the array
has more than one dimension, the sub-arrays of the first
dimension are sorted per normal array-comparison rules,
leaving their contents alone.
In support of this, add pg_type.typarray to the set of fields
cached by the typcache.
Author: Junwang Zhao <zhjwpku@gmail.com>
Co-authored-by: Jian He <jian.universality@gmail.com>
Reviewed-by: Aleksander Alekseev <aleksander@timescale.com>
Discussion: https://postgr.es/m/CAEG8a3J41a4dpw_-F94fF-JPRXYxw-GfsgoGotKcjs9LVfEEvw@mail.gmail.com
mdreadv() has a codepath to zero out buffers when a read returns zero bytes,
guarded by a check for zero_damaged_pages || InRecovery.
The InRecovery codepath to zero out buffers in mdreadv() appears to be
unreachable. The only known paths to reach mdreadv()/mdstartreadv() in
recovery are XLogReadBufferExtended(), vm_readbuf(), and fsm_readbuf(), each
of which takes care to extend the relation if necessary. This looks to either
have been the case for a long time, or the code was never reachable.
The zero_damaged_pages path is incomplete, as missing segments are not
created.
Putting blocks into the buffer-pool that do not exist on disk is rather
problematic, as such blocks will, at least initially, not be found by scans
that rely on smgrnblocks(), as they are beyond EOF. It also can cause weird
problems with relation extension, as relation extension does not expect blocks
beyond EOF to exist.
Therefore we would like to remove that path.
mdstartreadv(), which I added in e5fe570b51c, does not implement this zeroing
logic. I had started a discussion about that a while ago (linked below), but
forgot to act on the conclusion of the discussion, namely to disable the
in-memory-zeroing behavior.
We could certainly implement equivalent zeroing logic in mdstartreadv(), but
it would have to be more complicated due to potential differences in the
zero_damaged_pages setting between the definer and completor of IO. Given that
we want to remove the logic, that does not seem worth implementing the
necessary logic.
For now, put an Assert(false) and comments documenting this choice into
mdreadv() and comments documenting the deprecation of the path in mdreadv()
and the non-implementation of it in mdstartreadv(). If we, during testing,
discover that we do need the path, we can implement it at that time.
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/postgr.es/m/20250330024513.ac.nmisch@google.com
Discussion: https://postgr.es/m/postgr.es/m/3qxxsnciyffyf3wyguiz4besdp5t5uxvv3utg75cbcszojlz7p@uibfzmnukkbd
To make the tests possible, a few functions from bufmgr.c/localbuf.c had to be
exported, via buf_internals.h.
Reviewed-by: Noah Misch <noah@leadboat.com>
Co-authored-by: Andres Freund <andres@anarazel.de>
Co-authored-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
Due to splitting the block id into two 16 bit integers, BlockIdSet()
is more expensive than one might think. Doing it once per returned
tuple shows up as a small but reliably reproducible cost. It's simple
enough to set the block number just once per block in pagemode, so do
so.
Author: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/lxzj26ga6ippdeunz6kuncectr5gfuugmm2ry22qu6hcx6oid6@lzx3sjsqhmt6
Previously effective_io_concurrency and maintenance_io_concurrency could not
be set above 0 on machines without fadvise support. AIO enables IO concurrency
without such support, via io_method=worker.
Currently only subsystems using the read stream API will take advantage of
this. Other users of maintenance_io_concurrency (like recovery prefetching)
which leverage OS advice directly will not benefit from this change. In those
cases, maintenance_io_concurrency will have no effect on I/O behavior.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/CAAKRu_atGgZePo=_g6T3cNtfMf0QxpvoUh5OUqa_cnPdhLd=gw@mail.gmail.com
Submitting IO in larger batches can be more efficient than doing so
one-by-one, particularly for many small reads. It does, however, require
the ReadStreamBlockNumberCB callback to abide by the restrictions of AIO
batching (c.f. pgaio_enter_batchmode()). Basically, the callback may not:
a) block without first calling pgaio_submit_staged(), unless a
to-be-waited-on lock cannot be part of a deadlock, e.g. because it is
never held while waiting for IO.
b) directly or indirectly start another batch pgaio_enter_batchmode()
As this requires care and is nontrivial in some cases, batching is only
used with explicit opt-in.
This patch adds an explicit flag (READ_STREAM_USE_BATCHING) to read_stream and
uses it where appropriate.
There are two cases where batching would likely be beneficial, but where we
aren't using it yet:
1) bitmap heap scans, because the callback reads the VM
This should soon be solved, because we are planning to remove the use of
the VM, due to that not being sound.
2) The first phase of heap vacuum
This could be made to support batchmode, but would require some care.
Reviewed-by: Noah Misch <noah@leadboat.com>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
Adapt the read stream logic for real AIO:
- If AIO is enabled, we shouldn't issue advice, but if it isn't, we should
continue issuing advice
- AIO benefits from reading ahead with direct IO
- If effective_io_concurrency=0, pass READ_BUFFERS_SYNCHRONOUSLY to
StartReadBuffers() to ensure synchronous IO execution
There are further improvements we should consider:
- While in read_stream_look_ahead(), we can use AIO batch submission mode for
increased efficiency. That however requires care to avoid deadlocks and thus
done separately.
- It can be beneficial to defer starting new IOs until we can issue multiple
IOs at once. That however requires non-trivial heuristics to decide when to
do so.
Reviewed-by: Noah Misch <noah@leadboat.com>
Co-authored-by: Andres Freund <andres@anarazel.de>
Co-authored-by: Thomas Munro <thomas.munro@gmail.com>
This finally introduces the first actual use of AIO. StartReadBuffers() now
uses the AIO routines to issue IO.
As the implementation of StartReadBuffers() is also used by the functions for
reading individual blocks (StartReadBuffer() and through that
ReadBufferExtended()) this means all buffered read IO passes through the AIO
paths. However, as those are synchronous reads, actually performing the IO
asynchronously would be rarely beneficial. Instead such IOs are flagged to
always be executed synchronously. This way we don't have to duplicate a fair
bit of code.
When io_method=sync is used, the IO patterns generated after this change are
the same as before, i.e. actual reads are only issued in WaitReadBuffers() and
StartReadBuffers() may issue prefetch requests. This allows to bypass most of
the actual asynchronicity, which is important to make a change as big as this
less risky.
One thing worth calling out is that, if IO is actually executed
asynchronously, the precise meaning of what track_io_timing is measuring has
changed. Previously it tracked the time for each IO, but that does not make
sense when multiple IOs are executed concurrently. Now it only measures the
time actually spent waiting for IO. A subsequent commit will adjust the docs
for this.
While AIO is now actually used, the logic in read_stream.c will often prevent
using sufficiently many concurrent IOs. That will be addressed in the next
commit.
Reviewed-by: Noah Misch <noah@leadboat.com>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Co-authored-by: Andres Freund <andres@anarazel.de>
Co-authored-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
Discussion: https://postgr.es/m/20210223100344.llw5an2aklengrmn@alap3.anarazel.de
Discussion: https://postgr.es/m/stj36ea6yyhoxtqkhpieia2z4krnam7qyetc57rfezgk4zgapf@gcnactj4z56m
This commit implements the infrastructure to perform asynchronous reads into
the buffer pool.
To do so, it:
- Adds readv AIO callbacks for shared and local buffers
It may be worth calling out that shared buffer completions may be run in a
different backend than where the IO started.
- Adds an AIO wait reference to BufferDesc, to allow backends to wait for
in-progress asynchronous IOs
- Adapts StartBufferIO(), WaitIO(), TerminateBufferIO(), and their localbuf.c
equivalents, to be able to deal with AIO
- Moves the code to handle BM_PIN_COUNT_WAITER into a helper function, as it
now also needs to be called on IO completion
As of this commit, nothing issues AIO on shared/local buffers. A future commit
will update StartReadBuffers() to do so.
Buffer reads executed through this infrastructure will report invalid page /
checksum errors / warnings differently than before:
In the error case the error message will cover all the blocks that were
included in the read, rather than just the reporting the first invalid
block. If more than one block is invalid, the error will include information
about the range of the read, the first invalid block and the number of invalid
pages, with a HINT towards the server log for per-block details.
For the warning case (i.e. zero_damaged_buffers) we would previously emit one
warning message for each buffer in a multi-block read. Now there is only a
single warning message for the entire read, again referring to the server log
for more details in case of multiple checksum failures within a single larger
read.
Reviewed-by: Noah Misch <noah@leadboat.com>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
Discussion: https://postgr.es/m/20210223100344.llw5an2aklengrmn@alap3.anarazel.de
Discussion: https://postgr.es/m/stj36ea6yyhoxtqkhpieia2z4krnam7qyetc57rfezgk4zgapf@gcnactj4z56m
If an IO succeeds, but issues a warning, e.g. due to a page verification
failure with zero_damaged_pages, we want to issue that warning in the context
of the issuer of the IO, not the process that executes the completion (always
the case for worker).
It's already possible for a completion callback to report a custom error
message, we just didn't have a result status that allowed a user of AIO to
know that a warning should be emitted even though the IO request succeeded.
All that's needed for that is a dedicated PGAIO_RS_ value.
Previously there were not enough bits in PgAioResult.id for the new
value. Increase. While at that, add defines for the amount of bits and static
asserts to check that the widths are appropriate.
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20250329212929.a6.nmisch@google.com
For AIO the completion of a read into shared buffers (i.e. verifying the page
including the checksum, updating the BufferDesc to reflect the IO) can happen
in a different backend than the backend that started the IO. As
ignore_checksum_failure can differ between backends, we need to allow the
caller of PageIsVerified() control whether to ignore checksum failures.
The commit leaves a gap in the PIV_* values, as an upcoming commit, which
depends on this commit, will add PIV_LOG_LOG, which better fits just after
PIV_LOG_WARNING.
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20250329212929.a6.nmisch@google.com
For AIO we execute completion callbacks in critical sections (to ensure that
AIO can in the future be used for WAL, which in turn requires that we can call
completion callbacks in critical sections, to get the resources for WAL
io). To report checksum errors a backend now has to call
pgstat_prepare_report_checksum_failure(), before entering a critical section,
which guarantees the relevant pgstats entry is in shared memory, the relevant
DSM segment is mapped into the backend's memory and the address is known via a
PgStat_EntryRef.
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/wkjj4p2rmkevutkwc6tewoovdqznj6c6nvjmvii4oo5wmbh5sr@retq7d6uqs4j
We have errmsg_internal(), errdetail_internal(), but not errhint_internal().
Sometimes it is useful to output a hint with already translated format
string (e.g. because there different messages depending on the condition). For
message/detail we do that with the _internal() variants, but we can't do that
with hint today. It's possible to work around that that by using something
like
str = psprintf(translated_format, args);
ereport(...
errhint("%s", str);
but that's not exactly pretty and makes it harder to avoid memory leaks.
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/ym3dqpa4xcvoeknewcw63x77vnqdosbqcetjinb2zfoh65k55m@m4ozmwhr6lk6
For AIO on temporary table buffers the AIO subsystem needs to be able to
ensure a pin on a buffer while AIO is going on, even if the IO issuing query
errors out. Tracking the buffer in LocalRefCount does not work, as it would
cause CheckForLocalBufferLeaks() to assert out.
Instead, also track the refcount in BufferDesc.state, not just
LocalRefCount. This also makes local buffers behave a bit more akin to shared
buffers.
Note that we still don't need locking, AIO completion callbacks for local
buffers are executed in the issuing session (i.e. nobody else has access to
the BufferDesc).
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
Some of these comments have been wrong for a while (12f3867f55), some I
recently introduced (da7226993f, 55b454d0e1). This includes an update to a
comment in FlushBuffer(), which will be copied in a future commit.
These changes seem big enough to be worth doing in separate commits.
Suggested-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20250319212530.80.nmisch@google.com
Checksum failure stats could be attributed to the wrong database in two cases:
- when a read of a shared relation encountered a checksum error , it would be
attributed to the current database, instead of the "database" representing
shared relations
- when using CREATE DATABASE ... STRATEGY WAL_LOG checksum errors in the
source database would be attributed to the current database
The checksum stats reporting via PageIsVerifiedExtended(PIV_REPORT_STAT) does
not have access to the information about what database a page belongs to.
This fixes the issue by removing PIV_REPORT_STAT and delegating the
responsibility to report stats to the caller, which now can learn about the
number of stats via a new optional argument.
As this changes the signature of PageIsVerifiedExtended() and all callers
should adapt to the new signature, use the occasion to rename the function to
PageIsVerified() and remove the compatibility macro.
We could instead have fixed this by adding information about the database to
the args of PageIsVerified(), but there are soon-to-be-applied patches that
need to separate the stats reporting from the PageIsVerified() call
anyway. Those patches also include testing for the failure paths, something we
inexplicably have not had.
As there is no caller of pgstat_report_checksum_failure() left, remove it.
It'd be possible, but awkward to fix this in the back branches. We considered
doing the work not quite worth it, as mis-attributed stats should still elicit
concern. The emitted error messages do allow to attribute the errors
correctly.
Discussion: https://postgr.es/m/5tyic6epvdlmd6eddgelv47syg2b5cpwffjam54axp25xyq2ga@ptwkinxqo3az
Discussion: https://postgr.es/m/mglpvvbhighzuwudjxzu4br65qqcxsnyvio3nl4fbog3qknwhg@e4gt7npsohuz
ExecInitPartitionInfo() duplicates much of the logic in
ExecInitMerge(), except that it failed to handle DO NOTHING
actions. This would cause an "unknown action in MERGE WHEN clause"
error if a MERGE with any DO NOTHING actions attempted to insert into
a partition not already initialised by ExecInitModifyTable().
Bug: #18871
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Gurjeet Singh <gurjeet@singh.im>
Discussion: https://postgr.es/m/18871-b44e3c96de3bd2e8%40postgresql.org
Backpatch-through: 15
Currently, group_similar_or_args() permutes original positions of clauses
independently on whether it manages to find any groups of similar clauses.
While we are not providing any strict warranties on saving the original order
of OR-clauses, it is preferred that the original order be modified as little
as possible.
This commit changes the reordering algorithm of group_similar_or_args() in
the following way. We reorder each group of similar clauses so that the
first item of the group stays in place, but all the other items are moved
after it. So, if there are no similar clauses, the order of clauses stays
the same. When there are some groups, only required reordering happens while
the rest of the clauses remain in their places.
Reported-by: Andrei Lepikhov <lepihov@gmail.com>
Discussion: https://postgr.es/m/3ac7c436-81e1-4191-9caf-b0dd70b51511%40gmail.com
Reviewed-by: Pavel Borisov <pashkin.elfe@gmail.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Alena Rybakina <a.rybakina@postgrespro.ru>
The uuidv7_interval() function previously converted a shifted
microsecond-precision timestamp (64-bit integer) to another 64-bit
integer representing a timestamp with nanosecond precision. This
conversion caused overflow for dates beyond the year 2262. The
millisecond and sub-millisecond parts were then extracted from this
nanosecond-precision timestamp and stored in UUIDv7 values.
With this commit, the millisecond and sub-millisecond parts are stored
directly into the UUIDv7 value without being converted back to a
nanosecond precision timestamp. Following RFC 9562, the timestamp is
stored as an unsigned integer, enabling support for dates up to the
year 10889.
Reported and fixed by Andrey Borodin, with cosmetic changes and
regression tests by me.
Reported-by: Andrey Borodin <x4mmm@yandex-team.ru>
Author: Andrey Borodin <x4mmm@yandex-team.ru>
Discussion: https://postgr.es/m/96DEC2D9-659A-40E8-B7BA-AF5D162A9E21@yandex-team.ru
This was left out of the original patch for virtual generated columns
(commit 83ea6c5402).
This just involves a bit of extra work in the executor to expand the
generation expressions and run a "IS NOT NULL" test against them.
There is also a bit of work to make sure that not-null constraints are
checked during a table rewrite.
Author: jian he <jian.universality@gmail.com>
Reviewed-by: Xuneng Zhou <xunengzhou@gmail.com>
Reviewed-by: Navneet Kumar <thanit3111@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com
Modernize code in ExecRelCheck() and ExecConstraints() a bit,
preparing the way for some new code.
Co-authored-by: jian he <jian.universality@gmail.com>
Reviewed-by: Xuneng Zhou <xunengzhou@gmail.com>
Reviewed-by: Navneet Kumar <thanit3111@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com
This removes some setlocale() calls and a lot of commentary about how
dangerous that is. strftime_l() is from POSIX 2008, and on Windows we
use _wcsftime_l().
While here, adjust error message for strftime_l() failure: it does not
in practice set errno (even though POSIX says it could), so no %m.
Author: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/CA%2BhUKGJqVe0%2BPv9dvC9dSums_PXxGo9SWcxYAMBguWJUGbWz-A%40mail.gmail.com
check_createrole_self_grant and check_synchronized_standby_slots
were allocating memory on a LOG elevel without checking if the
allocation succeeded or not, which would have led to a segfault
on allocation failure.
On top of that, a number of callsites were using the ERROR level,
relying on erroring out rather than returning false to allow the
GUC machinery handle it gracefully. Other callsites used WARNING
instead of LOG. While neither being not wrong, this changes all
check_ functions do it consistently with LOG.
init_custom_variable gets a promoted elevel to FATAL to keep
the guc_malloc error handling in line with the rest of the
error handling in that function which already call FATAL. If
we encounter an OOM in this callsite there is no graceful
handling to be had, better to error out hard.
Backpatch the fix to check_createrole_self_grant down to v16
and the fix to check_synchronized_standby_slots down to v17
where they were introduced.
Author: Daniel Gustafsson <daniel@yesql.se>
Reported-by: Nikita <pm91.arapov@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Bug: #18845
Discussion: https://postgr.es/m/18845-582c6e10247377ec@postgresql.org
Backpatch-through: 16
Commit 62d712ecfd introduced the capability to calculate the same
queryId for queries with different lengths of constants in a list for an
IN clause. This behavior was originally enabled with a GUC
query_id_squash_values. After a discussion about the value of such a
GUC, it was decided to back out of the use of a GUC and make the
squashing behavior the only available option.
Author: Sami Imseih <samimseih@gmail.com>
Discussion: https://postgr.es/m/Z-LZyygkkNyA8-kR@msg.df7cb.de
Discussion: https://postgr.es/m/CA+q6zcVTK-3C-8NWV1oY2NZrvtnMCDqnyYYyk1T7WMUG65MeOQ@mail.gmail.com
This involves four different implementation strategies:
1. For Windows, we now require _configthreadlocale() to be available
and work (commit f1da075d9a), and the documentation says that the
object returned by localeconv() is in thread-local memory.
2. For glibc, we translate to nl_langinfo_l() calls, because it
offers the same information that way as an extension, and that API is
thread-safe.
3. For macOS/*BSD, use localeconv_l(), which is thread-safe.
4. For everything else, use uselocale() to set the locale for the
thread, and use a big ugly lock to defend against the returned object
being concurrently clobbered. In practice this currently means only
Solaris.
The new call is used in pg_locale.c, replacing calls to setlocale() and
localeconv().
Author: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/CA%2BhUKGJqVe0%2BPv9dvC9dSums_PXxGo9SWcxYAMBguWJUGbWz-A%40mail.gmail.com
Commit d45597f72f introduced the ability to change a not-null
constraint from NO INHERIT to INHERIT and vice versa, but we included
the SET noise word in the syntax for it. The SET turns out not to be
necessary and goes against what the SQL standard says for other ALTER
TABLE subcommands, so remove it.
This changes the way this command is processed for constraint types
other than not-null, so there are some error message changes.
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Suraj Kharage <suraj.kharage@enterprisedb.com>
Discussion: https://postgr.es/m/202503251602.vsxaehsyaoac@alvherre.pgsql
f31aad9b0 adjusted query jumbling so it no longer ignores NULL nodes
during the jumble. This added some overhead. Here we tune a few
things to make jumbling faster again. This makes jumbling perform
similar or even slightly faster than prior to that change.
Author: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAApHDvreP04nhTKuYsPw0F-YN+4nr4f=L72SPeFb81jfv+2c7w@mail.gmail.com
Previously NULL nodes were ignored. This could cause issues where the
computed query ID could match for queries where fields that are next to
each other in their Node struct where one field was NULL and the other
non-NULL. For example, the Query struct had distinctClause and sortClause
next to each other. If someone wrote;
SELECT DISTINCT c1 FROM t;
and then;
SELECT c1 FROM t ORDER BY c1;
these would produce the same query ID since, in the first query, we
ignored the NULL sortClause and appended the jumble bytes for the
distictClause. In the latter query, since we did nothing for the NULL
distinctClause then jumble the non-NULL sortClause, and since the node
representation stored is the same in both cases, the query IDs were
identical.
Here we fix this by always accounting for NULL nodes by recording that
we saw a NULL in the jumble buffer. This fixes the issue as the order that
the NULL is recorded isn't the same in the above two queries.
Author: Bykov Ivan <i.bykov@modernsys.ru>
Author: Michael Paquier <michael@paquier.xyz>
Author: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/aafce7966e234372b2ba876c0193f1e9%40localhost.localdomain
The implementation of FSM for indexes is simpler than heap, where 0 is
used to track if a page is in-use and (BLCKSZ - 1) if a page is free.
One comment in indexfsm.c and one description in the documentation of
pg_freespacemap were incorrect about that.
Author: Alex Friedman <alexf01@gmail.com>
Discussion: https://postgr.es/m/71eef655-c192-453f-ac45-2772fec2cb04@gmail.com
Backpatch-through: 13
Performing AIO using io_uring can be considerably faster than
io_method=worker, particularly when lots of small IOs are issued, as
a) the context-switch overhead for worker based AIO becomes more significant
b) the number of IO workers can become limiting
io_uring, however, is linux specific and requires an additional compile-time
dependency (liburing).
This implementation is fairly simple and there are substantial optimization
opportunities.
The description of the existing AIO_IO_COMPLETION wait event is updated to
make the difference between it and the new AIO_IO_URING_EXECUTION clearer.
Reviewed-by: Noah Misch <noah@leadboat.com>
Reviewed-by: Jakub Wartak <jakub.wartak@enterprisedb.com>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
Discussion: https://postgr.es/m/20210223100344.llw5an2aklengrmn@alap3.anarazel.de
Discussion: https://postgr.es/m/stj36ea6yyhoxtqkhpieia2z4krnam7qyetc57rfezgk4zgapf@gcnactj4z56m
The old naming pattern (mirroring liburing's naming) was inconsistent with
the (not yet introduced) callers. It seems better to get rid of the
inconsistency now than to grow more users of the odd naming.
Reported-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20250326001915.bc.nmisch@google.com
Otherwise the results of e.g. temp table buffer verification errors will not
reach bufmgr.c. Obviously that's not right. Found while expanding the tests
for invalid buffer contents.
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20250326001915.bc.nmisch@google.com
As reported by Noah, it's possible, although practically very unlikely, that
interrupts could be processed in between pgaio_io_reopen() and
pgaio_io_perform_synchronously(). Prevent that by explicitly holding
interrupts.
It also seems good to add an assertion to pgaio_io_before_prep() to ensure
that interrupts are held, as otherwise FDs referenced by the IO could be
closed during interrupt processing. All code in the aio series currently runs
the code with interrupts held, but it seems better to be paranoid.
Reviewed-by: Noah Misch <noah@leadboat.com>
Reported-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20250324002939.5c.nmisch@google.com
The brin_bloom_union() function combines two BRIN summaries, by merging
one filter into the other. With bloom, we have to decompress the filters
first, but the function failed to update the summary to store the merged
filter. As a consequence, the index may be missing some of the data, and
return false negatives.
This issue exists since BRIN bloom indexes were introduced in Postgres
14, but at that point the union function was called only when two
sessions happened to summarize a range concurrently, which is rare. It
got much easier to hit in 17, as parallel builds use the union function
to merge summaries built by workers.
Fixed by storing a pointer to the decompressed filter, and freeing the
original one. Free the second filter too, if it was decompressed. The
freeing is not strictly necessary, because the union is called in
short-lived contexts, but it's tidy.
Backpatch to 14, where BRIN bloom indexes were introduced.
Reported by Arseniy Mukhin, investigation and fix by me.
Reported-by: Arseniy Mukhin
Discussion: https://postgr.es/m/18855-1cf1c8bcc22150e6%40postgresql.org
Backpatch-through: 14
It seems potentially useful to label our shared libraries with version
information, now that a facility exists for retrieving that. This
patch labels them with the PG_VERSION string. There was some
discussion about using semantic versioning conventions, but that
doesn't seem terribly helpful for modules with no SQL-level presence;
and for those that do have SQL objects, we typically expect them
to support multiple revisions of the SQL definitions, so it'd still
not be very helpful.
I did not label any of src/test/modules/. It seems unnecessary since
we don't install those, and besides there ought to be someplace that
still provides test coverage for the original PG_MODULE_MAGIC macro.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/dd4d1b59-d0fe-49d5-b28f-1e463b68fa32@gmail.com
This macro allows dynamically loaded shared libraries (modules) to
provide a wired-in module name and version, and possibly other
compile-time-constant fields in future. This information can be
retrieved with the new pg_get_loaded_modules() function.
This feature is expected to be particularly useful for modules
that do not have any exposed SQL functionality and thus are
not associated with a SQL-level extension object. But even for
modules that do belong to extensions, being able to verify the
actual code version can be useful.
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Yurii Rashkovskii <yrashk@omnigres.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/dd4d1b59-d0fe-49d5-b28f-1e463b68fa32@gmail.com
These are useful general-purpose math functions which are included in
POSIX and C99, and are commonly included in other math libraries, so
expose them as SQL-callable functions.
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
Reviewed-by: Stepan Neretin <sncfmgg@gmail.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Dmitry Koval <d.koval@postgrespro.ru>
Reviewed-by: Alexandra Wang <alexandra.wang.oss@gmail.com>
Discussion: https://postgr.es/m/CAEZATCXpGyfjXCirFk9au+FvM0y2Ah+2-0WSJx7MO368ysNUPA@mail.gmail.com
custom_query_jumble (introduced in 5ac462e2b7 as a node field
attribute) is now assigned to the expanded reference name "eref" of
RangeTblEntry, adding in the query jumble computation the non-qualified
aliased relation name, without the list of column names. The relation
OID is removed from the query jumbling.
The effects of this change can be seen in the tests added by
3430215fe3, where pg_stat_statements (PGSS) entries are now grouped
using the relation name, ignoring the relation search_path may point at.
For example, these two relations are different, but are now grouped in a
single PGSS entry as they are assigned the same query ID:
CREATE TABLE foo1.tab (a int);
CREATE TABLE foo2.tab (b int);
SET search_path = 'foo1';
SELECT count(*) FROM tab;
SET search_path = 'foo2';
SELECT count(*) FROM tab;
SELECT count(*) FROM foo1.tab;
SELECT count(*) FROM foo2.tab;
SELECT query, calls FROM pg_stat_statements WHERE query ~ 'FROM tab';
query | calls
--------------------------+-------
SELECT count(*) FROM tab | 4
(1 row)
It is still possible to use an alias in the FROM clause to split these.
This behavior is useful for relations re-created with the same name,
where queries based on such relations would be grouped in the same
PGSS entry. For permanent schemas, it should not really matter in
practice. The main benefit is for workloads that use a lot of temporary
relations, which are usually re-created with the same name continuously.
These can be a heavy source of bloat in PGSS depending on the workload.
Such entries can now be grouped together, improving the user experience.
The original idea from Christoph Berg used catalog lookups to find
temporary relations, something that the query jumble has never done, and
it could cause some performance regressions. The idea to use
RangeTblEntry.eref and the relation name, applying the same rules for
all relations, temporary and not temporary, has been proposed by Tom
Lane. The documentation additions have been suggested by Sami Imseih.
Author: Michael Paquier <michael@paquier.xyz>
Co-authored-by: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Christoph Berg <myon@debian.org>
Reviewed-by: Lukas Fittl <lukas@fittl.com>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Discussion: https://postgr.es/m/Z9iWXKGwkm8RAC93@msg.df7cb.de
A node field marked with custom_query_jumble and query_jumble_ignore
would generate some code of a custom routine. The script is changed so
as custom_query_jumble behaves like the other options in this case,
query_jumble_ignore taking priority, with no code generated.
A comment related to the code generated for node types was misplaced.
Thinkos introduced in 5ac462e2b7.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/1324036.1742945060@sss.pgh.pa.us
For import and export, use schemaname/relname rather than
regclass.
This is more natural during export, fits with the other arguments
better, and it gives better control over error handling in case we
need to downgrade more errors to warnings.
Also, use text for the argument types for schemaname, relname, and
attname so that casts to "name" are not required.
Author: Corey Huinker <corey.huinker@gmail.com>
Discussion: https://postgr.es/m/CADkLM=ceOSsx_=oe73QQ-BxUFR2Cwqum7-UP_fPe22DBY0NerA@mail.gmail.com
Currently, createForeignKeyCheckTriggers() takes a Relation type as
its first argument, but it doesn't use that argument directly.
Instead, it fetches the relation OID by calling RelationGetRelid().
Therefore, it would be more consistent with other functions (e.g.,
createForeignKeyCheckTriggers()) to pass the relation OID directly
instead of the whole Relation.
Author: Amul Sul <amul.sul@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/CAAJ_b962c5AcYW9KUt_R_ER5qs3fUGbe4az-SP-vuwPS-w-AGA@mail.gmail.com
Split ATExecAlterConstraintInternal() into two functions:
ATExecAlterConstrDeferrability() and
ATExecAlterConstrInheritability(). This simplifies the code and
avoids unnecessary confusion caused by recursive code, which isn't
needed for ATExecAlterConstrInheritability().
(This also takes over the changes in commit 64224a834c, as the new
AlterConstrDeferrabilityRecurse() is essentially the old
ATExecAlterChildConstr().)
Author: Amul Sul <amul.sul@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/CAAJ_b962c5AcYW9KUt_R_ER5qs3fUGbe4az-SP-vuwPS-w-AGA@mail.gmail.com
Small fixes for commit f4e53e10b6: Add missing calls to
InvokeObjectPostAlterHook() and also CacheInvalidateRelcache(). The
former change could have a user-visible effect. The latter omission
might have caused other bugs, but it is not clear whether one actually
existed. With these changes, the code is now more consistent with
similar ALTER CONSTRAINT variants, especially the ones that set the
deferrability.
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/CAF1DzPVfOW6Kk=7SSh7LbneQDJWh=PbJrEC_Wkzc24tHOyQWGg@mail.gmail.com
The network (inet) support functions currently only supported a
hardcoded btree operator family. With the generalized compare type
facility, we can generalize this to support any operator family from
any index type that supports the required operators.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Co-authored-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
This option gives the possibility for query jumble to define a custom
routine for the field of a Node, extending support for
custom_query_jumble as a node field attribute. When dealing with
complex node structures, this can be simpler than having to enforce a
custom function across a full node.
Custom functions need to be defined in queryjumblefuncs.c, named as
_jumble${node}_${field}(), and use in input the JumbleState, the node
and its field. The field is not really required if we have the Node,
but it makes custom implementations somewhat easier to think about. The
code generated by gen_node_support.pl uses a macro called
JUMBLE_CUSTOM(), hiding the internals of the logic inside
queryjumblefuncs.c.
This will be used by an upcoming patch manipulating adding a custom
routine into a field of RangeTblEntry, but this facility can become
useful in more cases.
Reviewed-by: Christoph Berg <myon@debian.org>
Discussion: https://postgr.es/m/Z9y43-dRvb4EtxQ0@paquier.xyz
Reduces memory required for hash aggregation by avoiding an allocation
and a pointer in the TupleHashEntryData structure. That structure is
used for all buckets, whether occupied or not, so the savings is
substantial.
Discussion: https://postgr.es/m/AApHDvpN4v3t_sdz4dvrv1Fx_ZPw=twSnxuTEytRYP7LFz5K9A@mail.gmail.com
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Allows an "extra" argument that allocates extra memory at the end of
the MinimalTuple. This is important for callers that need to store
additional data, but do not want to perform an additional allocation.
Suggested-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAApHDvppeqw2pNM-+ahBOJwq2QmC0hOAGsmCpC89QVmEoOvsdg@mail.gmail.com
The entries aren't freed until the entire hash table is destroyed, so
use the Bump allocator to improve allocation speed, avoid wasting
space on the chunk header, and avoid wasting space due to the
power-of-two allocations.
Discussion: https://postgr.es/m/CAApHDvqv1aNB4cM36FzRwivXrEvBO_LsG_eQ3nqDXTjECaatOQ@mail.gmail.com
Reviewed-by: David Rowley
Until now max_files_per_process=N limited each backend to open N files in
total (minus a safety factor), even if there were already more files opened in
postmaster and inherited by backends. Change max_files_per_process to control
how many additional files each process is allowed to open.
The main motivation for this is the patch to add io_method=io_uring, which
needs to open one file for each backend. Without this patch, even if
RLIMIT_NOFILE is high enough, postmaster will fail in set_max_safe_fds() if
started with a high max_connections. The cause of the failure is that, until
now, set_max_safe_fds() subtracted the already open files from
max_files_per_process.
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/w6uiicyou7hzq47mbyejubtcyb2rngkkf45fk4q7inue5kfbeo@bbfad3qyubvs
Discussion: https://postgr.es/m/CAGECzQQh6VSy3KG4pN1d=h9J=D1rStFCMR+t7yh_Kwj-g87aLQ@mail.gmail.com
The bitmap heap scan skip fetch optimization skips fetching the heap
block when a page is set all-visible in the visibility map and no
columns from the table are needed to satisfy the query.
2b73a8cd33 and c3953226a0 changed the control flow of bitmap heap scan
to use the read stream API. The read stream API returns buffers
containing blocks to the user. To make this work with the skip fetch
optimization, we keep a count of the empty tuples we need to emit for
all the blocks skipped and only emit the empty tuples after processing
the next block fetched from the heap or at the end of the scan.
It's incorrect to recheck NULL tuples, so we must set `recheck` to false
before yielding control back to BitmapHeapNext(). This was done before
emitting any remaining empty tuples at the end of the scan but not for
empty tuples emitted during the scan. This meant that if a page fetched
from the heap did require recheck and set `recheck` to true and then we
emitted empty tuples for subsequent blocks, we would get wrong results.
Fix this by always setting `recheck` to false before emitting empty
tuples.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Tested-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/496f7acd-881c-4df3-9bd3-8f8534dfec26%40gmail.com
Introduce a new conflict type, multiple_unique_conflicts, to handle cases
where an incoming row during logical replication violates multiple UNIQUE
constraints.
Previously, the apply worker detected and reported only the first
encountered key conflict (insert_exists/update_exists), causing repeated
failures as each constraint violation needs to be handled one by one
making the process slow and error-prone.
With this patch, the apply worker checks all unique constraints upfront
once the first key conflict is detected and reports
multiple_unique_conflicts if multiple violations exist. This allows users
to resolve all conflicts at once by deleting all conflicting tuples rather
than dealing with them individually or skipping the transaction.
In the future, this will also allow us to specify different resolution
handlers for such a conflict type.
Add the stats for this conflict type in pg_stat_subscription_stats.
Author: Nisha Moond <nisha.moond412@gmail.com>
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Discussion: https://postgr.es/m/CABdArM7FW-_dnthGkg2s0fy1HhUB8C3ELA0gZX1kkbs1ZZoV3Q@mail.gmail.com
This field can be optionally set in a PlannedStmt through the planner
hook, giving extensions the possibility to assign an identifier related
to a computed plan. The backend is changed to report it in the backend
entry of a process running (including the extended query protocol), with
semantics and APIs to set or get it similar to what is used for the
existing query ID (introduced in the backend via 4f0b0966c8). The plan
ID is reset at the same timing as the query ID. Currently, this
information is not added to the system view pg_stat_activity; extensions
can access it through PgBackendStatus.
Some patches have been proposed to provide some features in the planning
area, where a plan identifier is used as a key to know the plan involved
(for statistics, plan storage and manipulations, etc.), and the point of
this commit is to provide an anchor in the backend that extensions can
rely on for future work. The reset of the plan identifier is
controlled by core and follows the same pattern as the query identifier
added in 4f0b0966c8.
The contents of this commit are extracted from a larger set proposed
originally by Lukas Fittl, that Sami Imseih has proposed as an
independent change, with a few tweaks sprinkled by me.
Author: Lukas Fittl <lukas@fittl.com>
Author: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAP53Pkyow59ajFMHGpmb1BK9WHDypaWtUsS_5DoYUEfsa_Hktg@mail.gmail.com
Discussion: https://postgr.es/m/CAA5RZ0vyWd4r35uUBUmhngv8XqeiJUkJDDKkLf5LCoWxv-t_pw@mail.gmail.com
During hot standby, ExpireAllKnownAssignedTransactionIds() and
ExpireOldKnownAssignedTransactionIds() functions mark old transactions
as no-longer running, but they failed to update xactCompletionCount
and latestCompletedXid. AFAICS it would not lead to incorrect query
results, because those functions effectively turn in-progress
transactions into aborted transactions and an MVCC snapshot considers
both as "not visible". But it could surprise GetSnapshotDataReuse()
and trigger the "TransactionIdPrecedesOrEquals(TransactionXmin,
RecentXmin))" assertion in it, if the apparent xmin in a backend would
move backwards. We saw this happen when GetCatalogSnapshot() would
reuse an older catalog snapshot, when GetTransactionSnapshot() had
already advanced TransactionXmin.
The bug goes back all the way to commit 623a9ba79b in v14 that
introduced the snapshot reuse mechanism, but it started to happen more
frequently with commit 952365cded which removed a
GetTransactionSnapshot() call from backend startup. That made it more
likely for ExpireOldKnownAssignedTransactionIds() to be called between
GetCatalogSnapshot() and the first GetTransactionSnapshot() in a
backend.
Andres Freund first spotted this assertion failure on buildfarm member
'skink'. Reproduction and analysis by Tomas Vondra.
Backpatch-through: 14
Discussion: https://www.postgresql.org/message-id/oey246mcw43cy4qw2hqjmurbd62lfdpcuxyqiu7botx3typpax%40h7o7mfg5zmdj
Add a new scheduling heuristic: don't end the ongoing primitive index
scan immediately (at the point where _bt_advance_array_keys notices that
the next set of matching tuples must be on a later page) if the primscan
already managed to step right/left from its first leaf page. Schedule a
recheck against the next sibling leaf page's finaltup instead.
The new heuristic tends to avoid scenarios where the top-level scan
repeatedly starts and ends primitive index scans that each read only one
leaf page from a group of neighboring leaf pages. Affected top-level
scans will now tend to step forward (or backward) through the index
instead, without wasting cycles on descending the index anew.
The recheck mechanism isn't exactly new. But up until now it has only
been used to deal with edge cases involving high key finaltups with one
or more truncated -inf attributes that _bt_advance_array_keys deemed
"provisionally satisfied" (satisfied for the purposes of allowing the
scan to step onto the next page, subject to recheck once on that page).
The mechanism was added by commit 5bf748b8, which invented the general
concept of primitive scan scheduling. It was later enhanced by commit
79fa7b3b, which taught it about cases involving -inf attributes that
satisfy inequality scan keys required in the opposite-to-scan direction
only (arguably, they should have been covered by the earliest version).
Now the recheck mechanism can be applied based on scan-level heuristics,
which have nothing to do with truncated high keys. Now rechecks might
be performed by _bt_readpage when scanning in _either_ scan direction.
The theory behind the new heuristic is that any primitive scan that
makes it past its first leaf page is one that is already likely to have
arrays whose key values match index tuples that are closely clustered
together in the index. The rules that determine whether we ever get
past the first page are still conservative (that'll still only happen
when pstate.finaltup strongly suggests that it's the right thing to do).
Surviving past the first leaf page is a strong signal in itself.
Preparation for an upcoming patch that will add skip scan optimizations
to nbtree. That'll work by adding skip arrays, which behave similarly
to SAOP arrays, but generate their elements procedurally and on-demand.
Note that this commit isn't specifically concerned with skip arrays; the
scheduling logic doesn't (and won't) condition anything on whether the
scan uses skip arrays, SAOP arrays, or some combination of the two
(which seems like a good general principle for _bt_advance_array_keys).
While the problems that this commit ameliorates are more likely with
skip arrays (at least in practice), SAOP arrays (or those with very
dense, contiguous array elements) are also affected.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/CAH2-Wzkz0wPe6+02kr+hC+JJNKfGtjGTzpG3CFVTQmKwWNrXNw@mail.gmail.com
Like 69273b818b did for GiST vacuuming, make SP-GiST vacuum use the
read stream API for vacuuming physically contiguous index pages.
Concurrent insertions may cause SP-GiST index tuples to be redirected.
While vacuuming, these are added to a pending list which is later
processed to ensure no dead tuples are left behind. Pages containing
such tuples are still read by directly calling ReadBuffer() and do not
use the read stream API.
Author: Andrey M. Borodin <x4mmm@yandex-team.ru>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/37432403-8657-403B-9CDF-5A642BECDD81%40yandex-team.ru
This code must have missed a memo about the backend type description
being supplied automatically these days, and was duplicating that
information.
Before: "io worker io worker: N"
After: "io worker N"
This commit introduces a new GUC option max_active_replication_origins
to control the maximum number of active replication
origins. Previously, this was controlled by
'max_replication_slots'. Having a separate GUC option provides better
flexibility for setting up subscribers, as they may not require
replication slots (for cascading replication) but always require
replication origins.
Author: Euler Taveira <euler@eulerto.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Discussion: https://postgr.es/m/b81db436-8262-4575-b7c4-bc0c1551000b@app.fastmail.com
Make genbki.pl emit some boilerplate comments identifying the
sections of the pg_*_d.h files that it generates. This is in
hopes of making them slightly more readable, in case people
look at those files and not the pg_*.h/pg_*.dat originals.
Discussion: https://postgr.es/m/1134562.1742507765@sss.pgh.pa.us
Like c5c239e26e did for btree vacuuming, make GiST vacuum use the
read stream API for sequentially processed pages.
Because it is possible for concurrent insertions to relocate unprocessed
index entries to already vacuumed pages, GiST vacuum must backtrack and
reprocess those pages. These pages are still read with explicit
ReadBuffer() calls.
Author: Andrey M. Borodin <x4mmm@yandex-team.ru>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/EFEBED92-18D1-4C0F-A4EB-CD47072EF071%40yandex-team.ru
c5c239e26e made btree vacuum use the read stream API. Though it used
functions declared in read_stream.h, it relied on transitively including
it. Explicitly include that file. Also remove an extraneous newline and
decrease the scope of one of the local variables in btvacuumscan().
Btree vacuum processes all index pages in physical order. Now it uses
the read stream API to get the next buffer instead of explicitly
invoking ReadBuffer().
It is possible for concurrent insertions to cause page splits during
index vacuuming. This can lead to index entries that have yet to be
vacuumed being moved to pages that have already been vacuumed. Btree
vacuum code handles this by backtracking to reprocess those pages. So,
while sequentially encountered pages are now read through the
read stream API, backtracked pages are still read with explicit
ReadBuffer() calls.
Author: Andrey Borodin <x4mmm@yandex-team.ru>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Discussion: https://postgr.es/m/flat/CAAKRu_bW1UOyup%3DjdFw%2BkOF9bCaAm%3D9UpiyZtbPMn8n_vnP%2Big%40mail.gmail.com#3b3a84132fc683b3ee5b40bc4c2ea2a5
All TupleDescAttr() calls in tablecmds.c that aren't in loops across all
attributes use AttrNumber-style indexes (1-based); there was only one
place in ATRewriteTable that was stashing 0-based indexes in a list for
later processing. Switch that to use attnums for consistency.
Author: jian he <jian.universality@gmail.com>
Discussion: https://postgr.es/m/CACJufxEoYA5ScUr2=CmA1xcpaS_1ixneDbEkVU77X1ctGxY2mA@mail.gmail.com
StartReadBuffers() reports a short read when it finds a cached block
that ends a range needing I/O by updating the caller's *nblocks. It
doesn't want to have to unpin the trailing hit that it knows the caller
wants, so the v17 version used sleight of hand in the name of
simplicity: it included it in *nblocks as if it were part of the I/O,
but internally tracked the shorter real I/O size in io_buffers_len (now
removed).
This API change "forwards" the delimiting buffer to the next call. It's
still pinned, and still stored in the caller's array, but *nblocks no
longer includes stray buffers that are not really part of the operation.
The expectation is that the caller still wants the rest of the blocks
and will call again starting from that point, and now it can pass the
already pinned buffer back in (or choose not to and release it).
The change is needed for the coming asynchronous I/O version's larger
version of the problem: by definition it must move BM_IO_IN_PROGRESS
negotiation from WaitReadBuffers() to StartReadBuffers(), but it might
already have many buffers pinned before it discovers a need to split an
I/O. (The current synchronous I/O version hides that detail from
callers by looping over smaller reads if required to make all covered
buffers valid in WaitReadBuffers(), so it looks like one operation but
it might occasionally be several under the covers.)
Aside from avoiding unnecessary pin traffic, this will also be important
for later work on out-of-order streams: you can't prioritize data that
is already available right now if that fact is hidden from you.
The new API is natural for read_stream.c (see ed0b87ca). After a short
read it leaves forwarded buffers where they fell in its circular queue
for the continuing call to pick up.
Single-block StartReadBuffer() and traditional ReadBuffer() share code
but are not affected by the change. They don't do multi-block I/O.
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier versions)
Discussion: https://postgr.es/m/CA%2BhUKGK_%3D4CVmMHvsHjOVrK6t4F%3DLBpFzsrr3R%2BaJYN8kcTfWg%40mail.gmail.com
In preparation for a follow-up change to the buffer manager, teach
read_stream.c to manage buffers "forwarded" from one StartReadBuffers()
call to the next after a short read. This involves a small amount of
extra book-keeping, and opens the way for lower levels to split I/O
operations without having to drop pins, as required for efficient
handling of various edge cases.
Concretely, the "buffers" argument will change from an out parameter to
an in/out parameter. Buffer queue elements must be initialized on first
use and cleared after they're consumed, but forwarded buffers are left
where they fall ahead of the current pending read in the queue, ready
for use by the operation that continues where a short read left off.
The stream also needs to count them for pin limit management and release
them on reset/early end.
Tested-by: Andres Freund <andres@anarazel.de> (earlier versions)
Discussion: https://postgr.es/m/CA%2BhUKGK_%3D4CVmMHvsHjOVrK6t4F%3DLBpFzsrr3R%2BaJYN8kcTfWg%40mail.gmail.com
This removes a needless special case for Memoize's FORMAT TEXT EXPLAIN
output.
ExplainPropertyText() outputs the same thing in text mode as the
special-case code was doing, so removing the special-case code results in
the same EXPLAIN output, just with less code.
It seems like a good idea to fix this to help prevent future changes in
this area from copying the same pattern.
Author: Ilia Evdokimov <ilya.evdokimov@tantorlabs.com>
Reported-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/88a71bcd-0b5c-4d0b-8107-757e96f402d5@tantorlabs.com
Previously we would have the following inaccuracies when a backend tried to
read in a buffer, but that buffer was read in concurrently by another backend:
- the read IO was double-counted in the global buffer access stats (pgBufferUsage)
- the buffer hit was not accounted for in:
- global buffer access statistics
- pg_stat_io
- relation level IO stats
- vacuum cost balancing
While trying to read in a buffer that is concurrently read in by another
backend is not a common occurrence, it's also not that rare, e.g. due to
concurrent sequential scans on the same relation. This scenario has become
more likely in PG 17, due to the introducing of read streams, which can pin
multiple buffers before calling StartBufferIO() for all the buffers.
This behaviour has historically grown, but there doesn't seem to be any reason
to continue with the wrong accounting.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_Zk-B08AzPsO-6680LUHLOCGaNJYofaxTFseLa=OepV1g@mail.gmail.com
We need to hold interrupts across most of the smgr.c/md.c functions, as
otherwise interrupt processing, e.g. due to a < ERROR elog/ereport, can
trigger procsignal processing, which in turn can trigger smgrreleaseall(). As
the relevant code is not reentrant, we quickly end up in a bad situation.
The only reason we haven't noticed this before is that there is only one
non-error ereport called in affected routines, in register_dirty_segments(),
and that one is extremely rarely reached. If one enables fd.c's FDDEBUG it's
easy to reproduce crashes.
It seems better to put the HOLD_INTERRUPTS()/RESUME_INTERRUPTS() in smgr.c,
instead of trying to push them down to md.c where possible: For one, every
smgr implementation would be vulnerable, for another, a good bit of smgr.c
code itself is affected too.
Eventually we might want a more targeted solution, allowing e.g. a networked
smgr implementation to be interrupted, but many other, more complicated,
problems would need to be fixed for that to be viable (e.g. smgr.c is often
called with interrupts already held).
One could argue this should be backpatched, but the existing < ERROR
elog/ereports that can be reached with unmodified sources are unlikely to be
reached. On balance the risk of backpatching seems higher than the gain - at
least for now.
Reviewed-by: Noah Misch <noah@leadboat.com>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/3vae7l5ozvqtxmd7rr7zaeq3qkuipz365u3rtim5t5wdkr6f4g@vkgf2fogjirl
Commit c65bc2e1d1 made it possible for
loadable modules to add EXPLAIN options. Normally, any necessary
validation can be performed by the hook function passed to
RegisterExtensionExplainOption, but if a loadable module wants to sanity
check options against each other, that needs to be done after the entire
options list has been processed. So, add an additional hook for that
purpose.
Author: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: http://postgr.es/m/CAA5RZ0vOcJF91O2e5AQN+V6guMNLMhJx83dxALf-iUZ-hLGO_Q@mail.gmail.com
This new parameter works just like the storage parameter of the
same name: if set to true (which is the default), autovacuum and
VACUUM attempt to truncate any empty pages at the end of the table.
It is primarily intended to help users avoid locking issues on hot
standbys. The setting can be overridden with the storage parameter
or VACUUM's TRUNCATE option.
Since there's presently no way to determine whether a Boolean
storage parameter is explicitly set or has just picked up the
default value, this commit also introduces an isset_offset member
to relopt_parse_elt.
Suggested-by: Will Storey <will@summercat.com>
Author: Nathan Bossart <nathandbossart@gmail.com>
Co-authored-by: Gurjeet Singh <gurjeet@singh.im>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Robert Treat <rob@xzilla.net>
Discussion: https://postgr.es/m/Z2DE4lDX4tHqNGZt%40dev.null
The comment explained that ALTER TABLE ADD CONSTRAINT USING INDEX is
only supported with a btree index. (This is not being changed.) The
reason is to keep upgrades robust, as explained there. The other part
of the comment, that btree is the only unique index kind anyway, is
somewhat less true as we're trying to enable unique indexes other than
btree, and it's irrelevant to this check. There is a check for
indisunique earlier already. So just remove this part of the comment.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
The new GUC extension_control_path specifies a path to look for
extension control files. The default value is $system, which looks in
the compiled-in location, as before.
The path search uses the same code and works in the same way as
dynamic_library_path.
Some use cases of this are: (1) testing extensions during package
builds, (2) installing extensions outside security-restricted
containers like Python.app (on macOS), (3) adding extensions to
PostgreSQL running in a Kubernetes environment using operators such as
CloudNativePG without having to rebuild the base image for each new
extension.
There is also a tweak in Makefile.global so that it is possible to
install extensions using PGXS into an different directory than the
default, using 'make install prefix=/else/where'. This previously
only worked when specifying the subdirectories, like 'make install
datadir=/else/where/share pkglibdir=/else/where/lib', for purely
implementation reasons. (Of course, without the path feature,
installing elsewhere was rarely useful.)
Author: Peter Eisentraut <peter@eisentraut.org>
Co-authored-by: Matheus Alcantara <matheusssilv97@gmail.com>
Reviewed-by: David E. Wheeler <david@justatheory.com>
Reviewed-by: Gabriele Bartolini <gabriele.bartolini@enterprisedb.com>
Reviewed-by: Marco Nenciarini <marco.nenciarini@enterprisedb.com>
Reviewed-by: Niccolò Fei <niccolo.fei@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E7C7BFFB-8857-48D4-A71F-88B359FADCFD@justatheory.com
Commit cbc127917e introduced tracking of unpruned relids to avoid
processing pruned relations, and changed ExecInitModifyTable() to
initialize only unpruned result relations. As a result, MERGE
statements that prune all target partitions can now lead to crashes
or incorrect behavior during execution.
The crash occurs because some executor code paths rely on
ModifyTableState.resultRelInfo[0] being present and initialized,
even when no result relations remain after pruning. For example,
ExecMerge() and ExecMergeNotMatched() use the first resultRelInfo
to determine the appropriate action. Similarly,
ExecInitPartitionInfo() assumes that at least one result relation
exists.
To preserve these assumptions, ExecInitModifyTable() now includes the
first result relation in the initialized result relation list if all
result relations for that ModifyTable were pruned. To enable that,
ExecDoInitialPruning() ensures the first relation is locked if it was
pruned and locking is necessary.
To support this exception to the pruning logic, PlannedStmt now
includes a list of RT indexes identifying the first result relation
of each ModifyTable node in the plan. This allows
ExecDoInitialPruning() to check whether each such relation was
pruned and, if so, lock it if necessary.
Bug: #18830
Reported-by: Robins Tharakan <tharakan@gmail.com>
Diagnozed-by: Tender Wang <tndrwang@gmail.com>
Diagnozed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Co-authored-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Discussion: https://postgr.es/m/18830-1f31ea1dc930d444%40postgresql.org
The default of 128kB is unchanged, but the upper limit is changed from
32 blocks to 128 blocks, unless the operating system's IOV_MAX is too
low. Some other RDBMSes seem to cap their multi-block buffer pool I/O
around this number, and it seems useful to allow experimentation.
The concrete change is to our definition of PG_IOV_MAX, which provides
the maximum for io_combine_limit and io_max_combine_limit. It also
affects a couple of other places that work with arrays of struct iovec
or smaller objects on the stack, so we still don't want to use the
system IOV_MAX directly without a clamp: it is not under our control and
likely to be 1024. 128 seems acceptable for our current usage.
For Windows, we can't use real scatter/gather yet, so we continue to
define our own IOV_MAX value of 16 and emulate preadv()/pwritev() with
loops. Someone would need to research the trade-offs of raising that
number.
NB if trying to see this working: you might temporarily need to hack
BAS_BULKREAD to be bigger, since otherwise the obvious way of "a very
big SELECT" is limited by that for now.
Suggested-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CA%2BhUKG%2B2T9p-%2BzM6Eeou-RAJjTML6eit1qn26f9twznX59qtCA%40mail.gmail.com
The existing io_combine_limit can be changed by users. The new
io_max_combine_limit is fixed at server startup time, and functions as a
silent clamp on the user setting. That in itself is probably quite
useful, but the primary motivation is:
aio_init.c allocates shared memory for all asynchronous IOs including
some per-block data, and we didn't want to waste memory you'd never used
by assuming they could be up to PG_IOV_MAX. This commit already halves
the size of 'AioHandleIov' and 'AioHandleData'. A follow-up commit can
now expand PG_IOV_MAX without affecting that.
Since our GUC system doesn't support dependencies or cross-checks
between GUCs, the user-settable one now assigns a "raw" value to
io_combine_limit_guc, and the lower of io_combine_limit_guc and
io_max_combine_limit is maintained in io_combine_limit.
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier version)
Discussion: https://postgr.es/m/CA%2BhUKG%2B2T9p-%2BzM6Eeou-RAJjTML6eit1qn26f9twznX59qtCA%40mail.gmail.com
Autovacuum launchers perform no WAL IO reads, but pgstat_tracks_io_op()
was tracking them as an allowed combination for the "init" and "normal"
contexts.
This caused the "read", "read_bytes" and "read_time" attributes of
pg_stat_io to show zeros for the autovacuum launcher rather than NULL.
NULL means that a combination of IO object, IO context and IO operation
has no meaning for a backend type. Zero is the same as telling that a
combination is relevant, and that WAL reads are possible in an
autovacuum launcher, but it is not relevant.
Copy-pasto introduced in a051e71e28.
Author: Ranier Vilela <ranier.vf@gmail.com>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/CAEudQAopEMAPiUqE7BvDV+x2fUPmKmb9RrsaoDR+hhQzLKg4PQ@mail.gmail.com
bbf668d66f lowered the minimum value of maintenance_work_mem to
64kB. However, in parallel vacuum cases, since the initial underlying
DSA size is 256kB, it attempts to perform a cycle of index vacuuming
and table vacuuming with an empty TID store, resulting in an assertion
failure.
This commit ensures that at least one page is processed before index
vacuuming and table vacuuming begins.
Backpatch to 17, where the minimum maintenance_work_mem value was
lowered.
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAD21AoCEAmbkkXSKbj4dB+5pJDRL4ZHxrCiLBgES_g_g8mVi1Q@mail.gmail.com
Backpatch-through: 17
This commit changes the backend stats code so as we rely on a single
boolean rather than a repeated check based on pg_memory_is_all_zeros()
in the code, making it cheaper should PgStat_PendingIO get bigger in
size.
The frequency of backend stats reports is not a bottleneck, but there is
no reason to not make that cheaper, and the logic is simple as the only
entry points updating backend IO stats are pgstat_count_backend_io_op()
and pgstat_count_backend_io_op_time().
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Xuneng Zhou <xunengzhou@gmail.com>
Discussion: https://postgr.es/m/Z8WYf1jyy4MwOveQ@ip-10-97-1-34.eu-west-3.compute.internal
pg_stat_statements produces multiple entries for queries like
SELECT something FROM table WHERE col IN (1, 2, 3, ...)
depending on the number of parameters, because every element of
ArrayExpr is individually jumbled. Most of the time that's undesirable,
especially if the list becomes too large.
Fix this by introducing a new GUC query_id_squash_values which modifies
the node jumbling code to only consider the first and last element of a
list of constants, rather than each list element individually. This
affects both the query_id generated by query jumbling, as well as
pg_stat_statements query normalization so that it suppresses printing of
the individual elements of such a list.
The default value is off, meaning the previous behavior is maintained.
Author: Dmitry Dolgov <9erthalion6@gmail.com>
Reviewed-by: Sergey Dudoladov (mysterious, off-list)
Reviewed-by: David Geier <geidav.pg@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Sutou Kouhei <kou@clear-code.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Marcos Pegoraro <marcos@f10.com.br>
Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Zhihong Yu <zyu@yugabyte.com>
Tested-by: Yasuo Honda <yasuo.honda@gmail.com>
Tested-by: Sergei Kornilov <sk@zsrv.org>
Tested-by: Maciek Sakrejda <m.sakrejda@gmail.com>
Tested-by: Chengxi Sun <sunchengxi@highgo.com>
Tested-by: Jakub Wartak <jakub.wartak@enterprisedb.com>
Discussion: https://postgr.es/m/CA+q6zcWtUbT_Sxj0V6HY6EZ89uv5wuG5aefpe_9n0Jr3VwntFg@mail.gmail.com
The previous commit introduced the infrastructure to start io_workers. This
commit actually makes the workers execute IOs.
IO workers consume IOs from a shared memory submission queue, run traditional
synchronous system calls, and perform the shared completion handling
immediately. Client code submits most requests by pushing IOs into the
submission queue, and waits (if necessary) using condition variables. Some
IOs cannot be performed in another process due to lack of infrastructure for
reopening the file, and must processed synchronously by the client code when
submitted.
For now the default io_method is changed to "worker". We should re-evaluate
that around beta1, we might want to be careful and set the default to "sync"
for 18.
Reviewed-by: Noah Misch <noah@leadboat.com>
Co-authored-by: Thomas Munro <thomas.munro@gmail.com>
Co-authored-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
Discussion: https://postgr.es/m/20210223100344.llw5an2aklengrmn@alap3.anarazel.de
Discussion: https://postgr.es/m/stj36ea6yyhoxtqkhpieia2z4krnam7qyetc57rfezgk4zgapf@gcnactj4z56m
This commit contains the basic, system-wide, infrastructure for
io_method=worker. It does not yet actually execute IO, this commit just
provides the infrastructure for running IO workers, kept separate for easier
review.
The number of IO workers can be adjusted with a PGC_SIGHUP GUC. Eventually
we'd like to make the number of workers dynamically scale up/down based on the
current "IO load".
To allow the number of IO workers to be increased without a restart, we need
to reserve PGPROC entries for the workers unconditionally. This has been
judged to be worth the cost. If it turns out to be problematic, we can
introduce a PGC_POSTMASTER GUC to control the maximum number.
As io workers might be needed during shutdown, e.g. for AIO during the
shutdown checkpoint, a new PMState phase is added. IO workers are shut down
after the shutdown checkpoint has been performed and walsender/archiver have
shut down, but before the checkpointer itself shuts down. See also
87a6690cc6.
Updates PGSTAT_FILE_FORMAT_ID due to the addition of a new BackendType.
Reviewed-by: Noah Misch <noah@leadboat.com>
Co-authored-by: Thomas Munro <thomas.munro@gmail.com>
Co-authored-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
Discussion: https://postgr.es/m/20210223100344.llw5an2aklengrmn@alap3.anarazel.de
Discussion: https://postgr.es/m/stj36ea6yyhoxtqkhpieia2z4krnam7qyetc57rfezgk4zgapf@gcnactj4z56m
Since many clients default to the X25519 curve in the TLS handshake,
the fact that the server by defualt doesn't support it cause an extra
roundtrip for each TLS connection. By adding multiple curves, which
is supported since 3d1ef3a15c, we can reduce the risk of extra
roundtrips.
Author: Daniel Gustafsson <daniel@yesql.se>
Co-authored-by: Jacob Champion <jacob.champion@enterprisedb.com>
Reported-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Jacob Champion <jacob.champion@enterprisedb.com>
Discussion: https://postgr.es/m/20240616234612.6cslu7nqexquvwj7@awork3.anarazel.de
Specifically, add a per-node hook that is called after the per-node
information has been displayed but before we display children, and a
per-query hook that is called after existing query-level information
is printed. This assumes that extension-added information should
always go at the end rather than the beginning or the middle, but
that seems like an acceptable limitation for simplicity. It also
assumes that extensions will only want to add information, not remove
or reformat existing details; those also seem like acceptable
restrictions, at least for now.
If multiple EXPLAIN extensions are used, the order in which any
additional details are printed is likely to depend on the order in
which the modules are loaded. That seems OK, since the user may
have opinions about the order in which output should appear, and the
extension author can't really know whether their stuff is more or
less important to a particular user than some other extension.
Discussion: http://postgr.es/m/CA+TgmoYSzg58hPuBmei46o8D3SKX+SZoO4K_aGQGwiRzvRApLg@mail.gmail.com
Reviewed-by: Srinath Reddy <srinath2133@gmail.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Since its introduction in fc34b0d9de, the default
maintenance_io_concurrency has been larger than the default
effective_io_concurrency. maintenance_io_concurrency primarily
controlled prefetching done on behalf of the whole system, for
operations like recovery. Therefore it makes sense for it to have a
value equal to or greater than effective_io_concurrency, which controls
I/O concurrency for reading a relation in a bitmap heap scan.
ff79b5b2ab increased effective_io_concurrency to 16, so we'll increase
maintenance_io_concurrency as well. For now, though, we'll keep the
defaults of effective_io_concurrency and maintenance_io_concurrency
equal to one another (16).
On fast, high IOPs systems, significantly higher values of
maintenance_io_concurrency are observably beneficial [1]. However, such
values would flood low IOPs systems and increase overall system I/O
latency.
It is worth mentioning that since 9256822608 and c3e775e608,
maintenance_io_concurrency also controls the I/O concurrency of each
vacuum worker. Since many autovacuum workers may be simultaneously
issuing I/Os, we want to keep maintenance_io_concurrency appropriately
conservative.
[1] https://postgr.es/m/c5d52837-6256-0556-ac8c-d6d3d558820a%40enterprisedb.com
Suggested-by: Jakub Wartak <jakub.wartak@enterprisedb.com>
Discussion: https://postgr.es/m/CAKZiRmxdHQaU%2B2Zpe6d%3Dx%3D0vigJ1sfWwwVYLJAf%3Dud_wQ_VcUw%40mail.gmail.com
Modules can use RegisterExtensionExplainOption to register new
EXPLAIN options, and GetExplainExtensionId, GetExplainExtensionState,
and SetExplainExtensionState to store related state inside the
ExplainState object.
Since this substantially increases the amount of code that needs
to handle ExplainState-related tasks, move a few bits of existing
code to a new file explain_state.c and add the rest of this
infrastructure there.
See the comments at the top of explain_state.c for further
explanation of how this mechanism works.
This does not yet provide a way for such such options to do anything
useful. The intention is that we'll add hooks for that purpose in a
separate commit.
Discussion: http://postgr.es/m/CA+TgmoYSzg58hPuBmei46o8D3SKX+SZoO4K_aGQGwiRzvRApLg@mail.gmail.com
Reviewed-by: Srinath Reddy <srinath2133@gmail.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
We were rejecting non-btree indexes in some cases owing to the
inability to determine the equality operators for other index AMs;
that problem no longer exists, because we can look up the equality
operator using COMPARE_EQ.
Stop rejecting these indexes, but instead rely on all unique indexes
having equality operators. Unique indexes must have equality
operators.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
We were rejecting non-btree indexes in some cases owing to the
inability to determine the equality operators for other index AMs;
that problem no longer exists, because we can look up the equality
operator using COMPARE_EQ. The problem of not knowing the strategy
number for equality in other index AMs is already resolved.
Stop rejecting the indexes upfront, and instead reject any for which
the equality operator lookup fails.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
Add get_opfamily_method() and get_opfamily_member_for_cmptype() in
lsyscache.c. No callers yet, but we'll add some soon. This is part
of generalizing some parts of the code away from having btree
hardcoded and use CompareType instead.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
The main motivations to use AIO in PostgreSQL are:
a) Reduce the time spent waiting for IO by issuing IO sufficiently early.
In a few places we have approximated this using posix_fadvise() based
prefetching, but that is fairly limited (no completion feedback, double the
syscalls, only works with buffered IO, only works on some OSs).
b) Allow to use Direct-I/O (DIO).
DIO can offload most of the work for IO to hardware and thus increase
throughput / decrease CPU utilization, as well as reduce latency. While we
have gained the ability to configure DIO in d4e71df6, it is not yet usable
for real world workloads, as every IO is executed synchronously.
For portability, the new AIO infrastructure allows to implement AIO using
different methods. The choice of the AIO method is controlled by the new
io_method GUC. As of this commit, the only implemented method is "sync",
i.e. AIO is not actually executed asynchronously. The "sync" method exists to
allow to bypass most of the new code initially.
Subsequent commits will introduce additional IO methods, including a
cross-platform method implemented using worker processes and a linux specific
method using io_uring.
To allow different parts of postgres to use AIO, the core AIO infrastructure
does not need to know what kind of files it is operating on. The necessary
behavioral differences for different files are abstracted as "AIO
Targets". One example target would be smgr. For boring portability reasons,
all targets currently need to be added to an array in aio_target.c. This
commit does not implement any AIO targets, just the infrastructure for
them. The smgr target will be added in a later commit.
Completion (and other events) of IOs for one type of file (i.e. one AIO
target) need to be reacted to differently, based on the IO operation and the
callsite. This is made possible by callbacks that can be registered on
IOs. E.g. an smgr read into a local buffer does not need to update the
corresponding BufferDesc (as there is none), but a read into shared buffers
does. This commit does not contain any callbacks, they will be added in
subsequent commits.
For now the AIO infrastructure only understands READV and WRITEV operations,
but it is expected that more operations will be added. E.g. fsync/fdatasync,
flush_range and network operations like send/recv.
As of this commit, nothing uses the AIO infrastructure. Later commits will add
an smgr target, md.c and bufmgr.c callbacks and then finally use AIO for
read_stream.c IO, which, in one fell swoop, will convert all read stream users
to AIO.
The goal is to use AIO in many more places. There are patches to use AIO for
checkpointer and bgwriter that are reasonably close to being ready. There also
are prototypes to use it for WAL, relation extension, backend writes and many
more. Those prototypes were important to ensure the design of the AIO
subsystem is not too limiting (e.g. WAL writes need to happen in critical
sections, which influenced a lot of the design).
A future commit will add an AIO README explaining the AIO architecture and how
to use the AIO subsystem. The README is added later, as it references details
only added in later commits.
Many many more people than the folks named below have contributed with
feedback, work on semi-independent patches etc. E.g. various folks have
contributed patches to use the read stream infrastructure (added by Thomas in
b5a9b18cd0) in more places. Similarly, a *lot* of folks have contributed to
the CI infrastructure, which I had started to work on to make adding AIO
feasible.
Some of the work by contributors has gone into the "v1" prototype of AIO,
which heavily influenced the current design of the AIO subsystem. None of the
code from that directly survives, but without the prototype, the current
version of the AIO infrastructure would not exist.
Similarly, the reviewers below have not necessarily looked at the current
design or the whole infrastructure, but have provided very valuable input. I
am to blame for problems, not they.
Author: Andres Freund <andres@anarazel.de>
Co-authored-by: Thomas Munro <thomas.munro@gmail.com>
Co-authored-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Co-authored-by: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Noah Misch <noah@leadboat.com>
Reviewed-by: Jakub Wartak <jakub.wartak@enterprisedb.com>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Dmitry Dolgov <9erthalion6@gmail.com>
Reviewed-by: Antonin Houska <ah@cybertec.at>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
Discussion: https://postgr.es/m/20210223100344.llw5an2aklengrmn@alap3.anarazel.de
Discussion: https://postgr.es/m/stj36ea6yyhoxtqkhpieia2z4krnam7qyetc57rfezgk4zgapf@gcnactj4z56m
This commit just does the minimal wiring up of the AIO subsystem, added in the
next commit, to the rest of the system. The next commit contains more details
about motivation and architecture.
This commit is kept separate to make it easier to review, separating the
changes across the tree, from the implementation of the new subsystem.
We discussed squashing this commit with the main commit before merging AIO,
but there has been a mild preference for keeping it separate.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
This reverts commit b860848232, that was added as a prerequisite for
the support of pgstats data flush across checkpoints, linking a pgstats
file to a specific checkpoint redo LSN.
As reported, this is proving to be currently problematic when going
through a pg_upgrade, that does direct manipulations of the control file
in the new cluster. The LSN stored in the pgstats file is not able to
cope with any changes done in the control file by pg_upgrade yet,
causing the pgstats file to be discarded when starting the new cluster
after overriding its redo LSN (one is a `pg_resetwal -l` where the new
cluster's start LSN is bumped by a hardcoded value of 8 segments, see
copy_xact_xlog_xid).
The least painful path going forward is likely going to be a refactor of
the pgstats code so as it is possible to read and write some of its data
with some routines in src/common/, so as pg_upgrade or pg_resetwal are
able to update its data. The main point is that we are going to need a
LSN in the stats file should we make it written at checkpoint time and
not only as part of a shutdown sequence. It is too late to dive into
these details for v18, so let's revert the change, and let's try to
figure out all the details in the next release cycle. The pgstats file
is currently only written as part of a shutdown sequence, and its
contents are still lost on crash, same as older releases.
Bump PGSTAT_FILE_FORMAT_ID.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/2563883.1741826489@sss.pgh.pa.us
To initiate IO on a shared buffer we have StartBufferIO(). For temporary table
buffers no similar function exists - likely because the code for that
currently is very simple due to the lack of concurrency.
However, the upcoming AIO support will make it possible to re-encounter a
local buffer, while the buffer already is the target of IO. In that case we
need to wait for already in-progress IO to complete. This commit makes it
easier to add the necessary code, by introducing StartLocalBufferIO().
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_b9anbWzEs5AAF9WCvcEVmgz-1AkHSQ-CLLy-p7WHzvFw@mail.gmail.com
Previously we had two paths implementing writing out temporary table
buffers. For shared buffers, the logic for that is centralized in
FlushBuffer(). Introduce FlushLocalBuffer() to do the same for local buffers.
Besides being a nice cleanup on its own, it also makes an upcoming change
slightly easier.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_b9anbWzEs5AAF9WCvcEVmgz-1AkHSQ-CLLy-p7WHzvFw@mail.gmail.com
Previously TerminateLocalBufferIO() was open-coded in multiple places, which
doesn't seem like a great idea. While TerminateLocalBufferIO() currently is
rather simple, an upcoming patch requires additional code to be added to
TerminateLocalBufferIO(), making this modification particularly worthwhile.
For some reason FlushRelationBuffers() previously cleared BM_JUST_DIRTIED,
even though that's never set for temporary buffers. This is not carried over
as part of this change.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_b9anbWzEs5AAF9WCvcEVmgz-1AkHSQ-CLLy-p7WHzvFw@mail.gmail.com
Previously, there were three copies of this code, two of them
identical. There's no good reason for that.
This change is nice on its own, but the main motivation is the AIO patchset,
which needs to add extra checks the deduplicated code, which of course is
easier if there is only one version.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_b9anbWzEs5AAF9WCvcEVmgz-1AkHSQ-CLLy-p7WHzvFw@mail.gmail.com
If PinLocalBuffer() were to modify the buf_state, the buf_state in
GetLocalVictimBuffer() would be out of date. Currently that does not happen,
as PinLocalBuffer() only modifies the buf_state if adjust_usagecount=true and
GetLocalVictimBuffer() passes false.
However, it's easy to make this not the case anymore - it cost me a few hours
to debug the consequences.
The minimal fix would be to just refetch the buf_state after after calling
PinLocalBuffer(), but the same danger exists in later parts of the
function. Instead, declare buf_state in the narrower scopes and re-read the
state in conditional branches. Besides being safer, it also fits well with
an upcoming set of cleanup patches that move the contents of the conditional
branches in GetLocalVictimBuffer() into helper functions.
I "broke" this in 794f259447.
Arguably this should be backpatched, but as the relevant functions are not
exported and there is no actual misbehaviour, I chose to not backpatch, at
least for now.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_b9anbWzEs5AAF9WCvcEVmgz-1AkHSQ-CLLy-p7WHzvFw@mail.gmail.com
After pushing the bitmap iterator into table-AM specific code (as part
of making bitmap heap scan use the read stream API in 2b73a8cd33),
scan_bitmap_next_block() no longer returns the current block number.
Since scan_bitmap_next_block() isn't returning any relevant information
to bitmap table scan code, it makes more sense to get rid of it.
Now, bitmap table scan code only calls table_scan_bitmap_next_tuple(),
and the heap AM implementation of scan_bitmap_next_block() is a local
helper in heapam_handler.c.
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/flat/CAAKRu_ZwCwWFeL_H3ia26bP2e7HiKLWt0ZmGXPVwPO6uXq0vaA%40mail.gmail.com
Make Bitmap Heap Scan use the read stream API instead of invoking
ReadBuffer() for each block indicated by the bitmap.
The read stream API handles prefetching, so remove all of the explicit
prefetching from bitmap heap scan code.
Now, heap table AM implements a read stream callback which uses the
bitmap iterator to return the next required block to the read stream
code.
Tomas Vondra conducted extensive regression testing of this feature.
Andres Freund, Thomas Munro, and I analyzed regressions and Thomas Munro
patched the read stream API.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Tested-by: Tomas Vondra <tomas@vondra.me>
Tested-by: Andres Freund <andres@anarazel.de>
Tested-by: Thomas Munro <thomas.munro@gmail.com>
Tested-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/flat/CAAKRu_ZwCwWFeL_H3ia26bP2e7HiKLWt0ZmGXPVwPO6uXq0vaA%40mail.gmail.com
Remove the TBMIterateResult member from the TBMPrivateIterator and
TBMSharedIterator and make tbm_[shared|private_]iterate() take a
TBMIterateResult as a parameter.
This allows tidbitmap API users to manage multiple TBMIterateResults per
scan. This is required for bitmap heap scan to use the read stream API,
with which there may be multiple I/Os in flight at once, each one with a
TBMIterateResult.
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/d4bb26c9-fe07-439e-ac53-c0e244387e01%40vondra.me
Make the distance control heuristics simpler and more aggressive in
preparation for asynchronous I/O.
The v17 version of read_stream.c made a conservative choice to limit the
look-ahead distance when streaming sequential blocks, because it
couldn't benefit very much from looking ahead further yet. It had a
three-behavior model where only random I/O would rapidly increase the
look-ahead distance, to support read-ahead advice. Sequential I/O would
move it towards the io_combine_limit setting, just enough to build one
full-sized synchronous I/O at a time, and then expect kernel read-ahead
to avoid I/O stalls.
That already left I/O performance on the table with advice-based I/O
concurrency, since sequential blocks could be followed by random jumps,
eg with the proposed streaming Bitmap Heap Scan patch.
It is time to delete the cautious middle option and adjust the distance
based on recent I/O needs only, since asynchronous reads will need to be
started ahead of time whether random or sequential. It is still limited
by io_combine_limit, *_io_concurrency, buffer availability and
strategy ring size, as before.
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier version)
Tested-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKGK_%3D4CVmMHvsHjOVrK6t4F%3DLBpFzsrr3R%2BaJYN8kcTfWg%40mail.gmail.com
read_stream.c tries not to issue read-ahead advice when it thinks the
kernel's own read-ahead should be active, ie when using buffered I/O and
reading sequential blocks. It previously gave up too easily, and issued
advice only for the first read of up to io_combine_limit blocks in a
larger range of sequential blocks after random jump. The following read
could suffer an avoidable I/O stall.
Fix, by continuing to issue advice until the corresponding preadv()
calls catch up with the start of the region we're currently issuing
advice for, if ever. That's when the kernel actually sees the
sequential pattern. Advice is now disabled only when the stream is
entirely sequential as far as we can see in the look-ahead window, or
in other words, when a sequential region is larger than we can cover
with the current io_concurrency and io_combine_limit settings.
While refactoring the advice control logic, also get rid of the
"suppress_advice" argument that was passed around between functions to
skip useless posix_fadvise() calls immediately followed by preadv().
read_stream_start_pending_read() can figure that out, so let's
concentrate knowledge of advice heuristics in fewer places (our goal
being to make advice-based I/O concurrency a legacy mode soon).
The problem cases were revealed by Tomas Vondra's extensive regression
testing with many different disk access patterns using Melanie
Plageman's streaming Bitmap Heap Scan patch, in a battle against the
venerable always-issue-advice-and-always-one-block-at-a-time code.
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier version)
Reported-by: Melanie Plageman <melanieplageman@gmail.com>
Reported-by: Tomas Vondra <tomas@vondra.me>
Reported-by: Andres Freund <andres@anarazel.de>
Tested-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKGK_%3D4CVmMHvsHjOVrK6t4F%3DLBpFzsrr3R%2BaJYN8kcTfWg%40mail.gmail.com
Discussion: https://postgr.es/m/CA%2BhUKGJ3HSWciQCz8ekP1Zn7N213RfA4nbuotQawfpq23%2Bw-5Q%40mail.gmail.com
This commit introduces a new GUC, log_lock_failure, which controls whether
a detailed log message is produced when a lock acquisition fails. Currently,
it only supports logging lock failures caused by SELECT ... NOWAIT.
The log message includes information about all processes holding or
waiting for the lock that couldn't be acquired, helping users analyze and
diagnose the causes of lock failures.
Currently, this option does not log failures from SELECT ... SKIP LOCKED,
as that could generate excessive log messages if many locks are skipped,
causing unnecessary noise.
This mechanism can be extended in the future to support for logging
lock failures from other commands, such as LOCK TABLE ... NOWAIT.
Author: Yuki Seino <seinoyu@oss.nttdata.com>
Co-authored-by: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Jelte Fennema-Nio <postgres@jeltef.nl>
Discussion: https://postgr.es/m/411280a186cc26ef7034e0f2dfe54131@oss.nttdata.com
This commit improves efficiency in FastPathTransferRelationLocks()
and GetLockConflicts(), which iterate over PGPROCs to search for
fast-path locks.
Previously, these functions recalculated the fast-path group during
every loop iteration, even though it remained constant. This update
optimizes the process by calculating the group once and reusing it
throughout the loop.
The functions also now skip empty fast-path groups, avoiding
unnecessary scans of their slots. Additionally, groups belonging to
inactive backends (with pid=0) are always empty, so checking
the group is sufficient to bypass these backends, further enhancing
performance.
Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: https://postgr.es/m/07d5fd6a-71f1-4ce8-8602-4cc6883f4bd1@oss.nttdata.com
PrepareSortSupportFromIndexRel() was accepting btree strategy numbers
purely for the purpose of comparing it later against btree strategies
to determine if the sort direction was forward or reverse. Change
that. Instead, pass a bool directly, to indicate the same without an
unfortunate assumption that a strategy number refers specifically to a
btree strategy. (This is similar in spirit to commits 0d2aa4d493 and
c594f1ad2ba.)
(This could arguably be simplfied further by having the callers fill
in ssup_reverse directly. But this way, it preserves consistency by
having all PrepareSortSupport*() variants be responsible for filling
in ssup_reverse.)
Moreover, remove the hardcoded check against BTREE_AM_OID, and check
against amcanorder instead, which is the actual requirement.
Co-authored-by: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
It doesn't actually work, even with allow_system_table_mods turned on:
the ALTER TABLE operation is rejected by ATSimplePermissions(), so even
the error message we're adding in this commit is unreachable.
Add a test case for it.
Author: Nikolay Shaplov <dhyan@nataraj.su>
Discussion: https://postgr.es/m/1913854.tdWV9SEqCh@thinkpad-pgpro
To avoid pinning too much of the buffer pool at once, read_stream.c
previously used LimitAdditionalPins(). The coding was naive, and only
considered the available buffers at stream construction time.
This commit checks before each StartReadBuffers() call with
GetAdditionalPinLimit(). The result might change over time due to pins
acquired outside this stream by the same backend. No extra CPU cycles
are added to the all-buffered fast-path code, but the I/O-starting path
now considers the up-to-date remaining buffer limit.
In practice it was quite difficult to exceed limits and cause any real
problems in v17, so no back-patch for now, but proposed changes will
make it easier.
Per code review from Andres, in the course of testing his AIO patches.
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier versions)
Discussion: https://postgr.es/m/CA%2BhUKGK_%3D4CVmMHvsHjOVrK6t4F%3DLBpFzsrr3R%2BaJYN8kcTfWg%40mail.gmail.com
Previously the support functions assumed that the caller needed one pin
to make progress, and could optionally use some more, allowing enough
for every connection to do the same. Add a couple more functions for
callers that want to know:
* what the maximum possible number could be, irrespective of currently
held pins, for space planning purposes
* how many additional pins they could acquire right now, without the
special case allowing one pin, for callers that already hold pins and
could already make progress even if no extra pins are available
The pin limit logic began in commit 31966b15. This refactoring is
better suited to read_stream.c, which will be adjusted to respect the
remaining limit as it changes over time in a follow-up commit. It also
computes MaxProportionalPins up front, to avoid performing divisions
whenever a caller needs to check the balance.
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier versions)
Discussion: https://postgr.es/m/CA%2BhUKGK_%3D4CVmMHvsHjOVrK6t4F%3DLBpFzsrr3R%2BaJYN8kcTfWg%40mail.gmail.com
The problem is that ALTER SUBSCRIPTION ... SET PUBLICATION ... will lead
to restarting of apply worker and after the restart, the apply worker will
use the existing slot and replication origin corresponding to the
subscription. Now, it is possible that before the restart, the origin has
not been updated, and the WAL start location points to a location before
where PUBLICATION pointed to by SET PUBLICATION doesn't exist, and that
can lead to an error like: "ERROR: publication "pub1" does not exist".
Once this error occurs, apply worker will never be able to proceed and
will always return the same error.
We decided to skip loading the publication if the publication does not
exist. The publication is loaded later and updates the relation entry when
the publication gets created.
We decided not to backpatch this as this is a behaviour change, and we don't
see field reports. This problem has been found by intermittent buildfarm
failures.
Author: vignesh C <vignesh21@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/flat/CALDaNm0-n8FGAorM%2BbTxkzn%2BAOUyx5%3DL_XmnvOP6T24%2B-NcBKg%40mail.gmail.com
Discussion: https://postgr.es/m/CAA4eK1+T-ETXeRM4DHWzGxBpKafLCp__5bPA_QZfFQp7-0wj4Q@mail.gmail.com
If the given input_type yields valid results from both
get_element_type and get_array_type, initArrayResultAny believed the
former and treated the input as an array type. However this is
inconsistent with what get_promoted_array_type does, leading to
situations where the output of an ARRAY() subquery is labeled with
the wrong type: it's labeled as oidvector[] but is really a 2-D
array of OID. That at least results in strange output, and can
result in crashes if further processing such as unnest() is applied.
AFAIK this is only possible with the int2vector and oidvector
types, which are special-cased to be treated mostly as true arrays
even though they aren't quite.
Fix by switching the logic to match get_promoted_array_type by
testing get_array_type not get_element_type, and remove an Assert
thereby made pointless. (We need not introduce a symmetrical
check for get_element_type in the other if-branch, because
initArrayResultArr will check it.) This restores the behavior
that existed before bac27394a introduced initArrayResultAny:
the output really is int2vector[] or oidvector[].
Comparable confusion exists when an input of an ARRAY[] construct
is int2vector or oidvector: transformArrayExpr decides it's dealing
with a multidimensional array constructor, and we end up with
something that's a multidimensional OID array but is alleged to be
of type oidvector. I have not found a crashing case here, but it's
easy to demonstrate totally-wrong results. Adjust that code so
that what you get is an oidvector[] instead, for consistency with
ARRAY() subqueries. (This change also makes these types work like
domains-over-arrays in this context, which seems correct.)
Bug: #18840
Reported-by: yang lei <ylshiyu@126.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18840-fbc9505f066e50d6@postgresql.org
Backpatch-through: 13
We can make the output look a bit better by aligning each lock's
definition, so add some padding space to achieve that. This change
makes no practical difference, but casual onlookers will be less
distracted by (lack of) whitespace.
Author: Gurjeet Singh <gurjeet@singh.im>
Discussion: https://postgr.es/m/CABwTF4VxfwDtRV-H22_XK4XeDogaV-Vaobu+af5U=8ZAZn9ZZQ@mail.gmail.com
We want to support a "noreturn" decoration on more compilers besides
just GCC-compatible ones, but for that we need to move the decoration
in front of the function declaration instead of either behind it or
wherever, which is the current style afforded by GCC-style attributes.
Also rename the macro to "pg_noreturn" to be similar to the C11
standard "noreturn".
pg_noreturn is now supported on all compilers that support C11 (using
_Noreturn), as well as GCC-compatible ones (using __attribute__, as
before), as well as MSVC (using __declspec). (When PostgreSQL
requires C11, the latter two variants can be dropped.)
Now, all supported compilers effectively support pg_noreturn, so the
extra code for !HAVE_PG_ATTRIBUTE_NORETURN can be dropped.
This also fixes a possible problem if third-party code includes
stdnoreturn.h, because then the current definition of
#define pg_attribute_noreturn() __attribute__((noreturn))
would cause an error.
Note that the C standard does not support a noreturn attribute on
function pointer types. So we have to drop these here. There are
only two instances at this time, so it's not a big loss. In one case,
we can make up for it by adding the pg_noreturn to a wrapper function
and adding a pg_unreachable(), in the other case, the latter was
already done before.
Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/flat/pxr5b3z7jmkpenssra5zroxi7qzzp6eswuggokw64axmdixpnk@zbwxuq7gbbcw
When pulling up a subquery, if the subquery's target list items are
used in grouping set columns, we need to wrap them in PlaceHolderVars.
This ensures that expressions retain their separate identity so that
they will match grouping set columns when appropriate.
In 90947674f, we decided to wrap subquery outputs that are non-var
expressions in PlaceHolderVars. This prevents const-simplification
from merging them into the surrounding expressions after subquery
pullup, which could otherwise lead to failing to match those
subexpressions to grouping set columns, with the effect that they'd
not go to null when expected.
However, that left some loose ends. If the subquery's target list
contains two or more identical Var expressions, we can still fail to
match the Var expression to the expected grouping set expression.
This is not related to const-simplification, but rather to how we
match expressions to lower target items in setrefs.c.
For sort/group expressions, we use ressortgroupref matching, which
works well. For other expressions, we primarily rely on comparing the
expressions to determine if they are the same. Therefore, we need a
way to prevent setrefs.c from matching the expression to some other
identical ones.
To fix, wrap all subquery outputs in PlaceHolderVars if the parent
query uses grouping sets, ensuring that they preserve their separate
identity throughout the whole planning process.
Reported-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Discussion: https://postgr.es/m/CAMbWs4-meSahaanKskpBn0KKxdHAXC1_EJCVWHxEodqirrGJnw@mail.gmail.com
In pull_up_simple_subquery and pull_up_constant_function, there is
code that sets wrap_non_vars to true when dealing with an appendrel
member. The goal is to wrap subquery outputs that are not simple Vars
in PlaceHolderVars, ensuring that what we pull up doesn't get merged
into a surrounding expression during later processing, which could
cause it to fail to match the expression actually available from the
appendrel.
However, this is unnecessary. When pulling up an appendrel child
subquery, the only part of the upper query that could reference the
appendrel child yet is the translated_vars list of the associated
AppendRelInfo that we just made for this child. Furthermore, we do
not want to force use of PHVs in the AppendRelInfo, as there is no
outer join between. In fact, perform_pullup_replace_vars always sets
wrap_non_vars to false before performing pullup_replace_vars on the
AppendRelInfo.
This patch simply removes the code that sets wrap_non_vars to true for
UNION ALL subqueries.
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Discussion: https://postgr.es/m/CAMbWs4-VXDEi1v+hZYLxpOv0riJxHsCkCH1f46tLnhonEAyGCQ@mail.gmail.com
On Publication rename, we need to only invalidate the RelationSyncCache
entries corresponding to relations that are part of the publication being
renamed.
As part of this patch, we introduce a new invalidation message to
invalidate the cache maintained by the logical decoding output plugin. We
can't use existing relcache invalidation for this purpose, as that would
unnecessarily cause relcache invalidations in other backends.
This will improve performance by building fewer relation cache entries
during logical replication.
Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Author: Shlok Kyal <shlok.kyal.oss@gmail.com>
Reviewed-by: Hou Zhijie <houzj.fnst@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/OSCPR01MB14966C09AA201EFFA706576A7F5C92@OSCPR01MB14966.jpnprd01.prod.outlook.com
In a couple of places, read_stream.c assumed that io_combine_limit would
be stable during the lifetime of a stream. That is not true in at least
one unusual case: streams held by CURSORs where you could change the GUC
between FETCH commands, with unpredictable results.
Fix, by storing stream->io_combine_limit and referring only to that
after construction. This mirrors the treatment of the other important
setting {effective,maintenance}_io_concurrency, which is stored in
stream->max_ios.
One of the cases was the queue overflow space, which was sized for
io_combine_limit and could be overrun if the GUC was increased. Since
that coding was a little hard to follow, also introduce a variable for
better readability instead of open-coding the arithmetic. Doing so
revealed an off-by-one thinko while clamping max_pinned_buffers to
INT16_MAX, though that wasn't a live bug due to the current limits on
GUC values.
Back-patch to 17.
Discussion: https://postgr.es/m/CA%2BhUKG%2B2T9p-%2BzM6Eeou-RAJjTML6eit1qn26f9twznX59qtCA%40mail.gmail.com
Commit 3c152a27b0 mistakenly repeated JSONTYPE_JSON in a condition,
omitting JSONTYPE_CAST. As a result, datum_to_jsonb_internal() failed
to reject inputs that were casts (e.g., from an enum to json as in the
example below) when used as keys in JSON constructors.
This led to a crash in cases like:
SELECT JSON_OBJECT('happy'::mood: '123'::jsonb);
where 'happy'::mood is implicitly cast to json. The missing check
meant such casted values weren’t properly rejected as invalid
(non-scalar) JSON keys.
Reported-by: Maciek Sakrejda <maciek@pganalyze.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Maciek Sakrejda <maciek@pganalyze.com>
Discussion: https://postgr.es/m/CADXhmgTJtJZK9A3Na_ry+Xrq-ghjcejBRhcRMzWZvbd__QdgJA@mail.gmail.com
Backpatch-through: 17
There used to be bespoken pools for these structs to reduce the
palloc/pfree overhead, but that was ripped out a long time ago and
replaced with the generic, cheaper generational memory allocator
(commit a4ccc1cef5). The Get/Return terminology made sense with the
pools, as you "got" an object from the pool and "returned" it later,
but now it just looks weird. Rename to Alloc/Free.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/c9e43d2d-8e83-444f-b111-430377368989@iki.fi
The only caller, select_best_grantor(), can instead use
pg_popcount64(). This isn't performance-critical code, but we
might as well use the centralized implementation. While at it, add
some test coverage for this part of select_best_grantor().
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/Z9GtL7Nm6hsYyJnF%40nathan
We did not wake up on interrupts while waiting on async events on an
async-capable append node. For example, if you tried to cancel the
query, nothing would happen until one of the async subplans becomes
readable. To fix, add WL_LATCH_SET to the WaitEventSet.
Backpatch down to v14 where async Append execution was introduced.
Discussion: https://www.postgresql.org/message-id/37a40570-f558-40d3-b5ea-5c2079b3b30b@iki.fi
makeWholeRowVar() has different rules for constructing a
whole-row Var depending on the kind of RTE it's representing.
This turns out to be problematic because the rewriter and planner
can convert view RTEs and set-returning-function RTEs into
subquery RTEs; so a whole-row Var made during planning might
look different from one made by the parser. In isolation this
doesn't cause any problem, but if a query contains Vars made
both ways for the same varno, there are cross-checks in the
executor that will complain. This manifests for UPDATE, DELETE,
and MERGE queries that use whole-row table references.
To fix, we need makeWholeRowVar() to produce the same result
from an inlined RTE as it would have for the original. For
an inlined view, we can use RangeTblEntry.relid to detect
that this had been a view RTE. For inlined SRFs, make a
data structure definition change akin to commit 47bb9db75,
and say that we won't clear RangeTblEntry.functions until
the end of planning. That allows makeWholeRowVar() to
repeat what it would have done with the unmodified RTE.
Reported-by: Duncan Sands <duncan.sands@deepbluecap.com>
Reported-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Diagnosed-by: Tender Wang <tndrwang@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Discussion: https://postgr.es/m/3518c50a-ab18-482f-b916-a37263622501@deepbluecap.com
Backpatch-through: 13
Add log_connections option 'setup_durations' which logs durations of
several key parts of connection establishment and backend setup.
For an incoming connection, starting from when the postmaster gets a
socket from accept() and ending when the forked child backend is first
ready for query, there are multiple steps that could each take longer
than expected due to external factors. This logging provides visibility
into authentication and fork duration as well as the end-to-end
connection establishment and backend initialization time.
To make this portable, the timings captured in the postmaster (socket
creation time, fork initiation time) are passed through the
BackendStartupData.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Jacob Champion <jacob.champion@enterprisedb.com>
Reviewed-by: Jelte Fennema-Nio <postgres@jeltef.nl>
Reviewed-by: Guillaume Lelarge <guillaume.lelarge@dalibo.com>
Discussion: https://postgr.es/m/flat/CAAKRu_b_smAHK0ZjrnL5GRxnAVWujEXQWpLXYzGbmpcZd3nLYw%40mail.gmail.com
Convert the boolean log_connections GUC into a list GUC comprised of the
connection aspects to log.
This gives users more control over the volume and kind of connection
logging.
The current log_connections options are 'receipt', 'authentication', and
'authorization'. The empty string disables all connection logging. 'all'
enables all available connection logging.
For backwards compatibility, the most common values for the
log_connections boolean are still supported (on, off, 1, 0, true, false,
yes, no). Note that previously supported substrings of on, off, true,
false, yes, and no are no longer supported.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/flat/CAAKRu_b_smAHK0ZjrnL5GRxnAVWujEXQWpLXYzGbmpcZd3nLYw%40mail.gmail.com
9a8dd2c5a6 has added an initialization to PendingBackendStats, which
has been causing compilation warnings in the buildfarm. This code does
not strictly require it as PendingBackendStats is always initialized
with memset(0), so let's remove it.
Per report from multiple buildfarm members, like ayu and batfish, via
Tom Lane.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/1870853.1741749264@sss.pgh.pa.us
The comment in GetTransactionSnapshot() said that you "should call
RegisterSnapshot or PushActiveSnapshot on the returned snap if it is
to be used very long". That felt too unclear to me. Make the comment
more strongly worded.
To enforce that rule and to catch potential bugs where a snapshot
might get invalidated while it's still in use, add an assertion to
HeapTupleSatisfiesMVCC() to check that the snapshot is registered or
pushed to active stack. No new bugs were found by this, but it seems
like good future-proofing. It's not a great place for the check;
HeapTupleSatisfiesMVCC() is in fact safe to call with an unregistered
snapshot, and the assertion won't catch other unsafe uses. But it goes
a long way in practice.
Fix a few cases that were playing fast and loose with that and just
assumed that the snapshot cannot be invalidated during a scan. Those
assumptions were not wrong, but they're not performance critical, so
let's drop the excuses and just register the snapshot. These were
false positives found by the new assertion.
Discussion: https://www.postgresql.org/message-id/7c56f180-b9e1-481e-8c1d-efa63de3ecbb@iki.fi
Previously, pg_logicalinspect functions were too trusting of their
input and blindly passed it to SnapBuildRestoreSnapshot(). If the
input pointed to a directory, the server could a PANIC error while
attempting to fsync_fname() with isdir=false on a directory.
This commit adds validation checks for input filenames and passes the
LSN extracted from the filename to SnapBuildRestoreSnapshot() instead
of the filename itself. It also adds regression tests for various
input patterns and permission checks.
Bug: #18828
Reported-by: Robins Tharakan <tharakan@gmail.com>
Co-authored-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Co-authored-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/18828-0f4701c635064211@postgresql.org
Up to now we just punted on showing the window definitions used
in a plan, with window function calls represented as "OVER (?)".
To improve that, show the window definition implemented by each
WindowAgg plan node, and reference their window names in OVER.
For nameless window clauses generated by "OVER (...)", assign
unique names w1, w2, etc.
In passing, re-order the properties shown for a WindowAgg node
so that the Run Condition (if any) appears after the Window
property and before the Filter (if any). This seems more
sensible since the Run Condition is associated with the Window
and acts before the Filter.
Thanks to David G. Johnston and Álvaro Herrera for design
suggestions.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/144530.1741469955@sss.pgh.pa.us
Make nbtree's "1/3 of a page limit" BTMaxItemSize function-like macro
(which accepts a "page" argument) into an object-like macro that can be
used from code that doesn't have convenient access to an nbtree page.
Preparation for an upcoming patch that adds skip scan to nbtree.
Parallel index scans that use skip scan will serialize datums (not just
SAOP array subscripts) when scheduling primitive scans. BTMaxItemSize
will be used by btestimateparallelscan to determine how much DSM to
request.
Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-Wz=H_RG5weNGeUG_TkK87tRBnH9mGCQj6WpM4V4FNWKv2g@mail.gmail.com
Expose the count of index searches/index descents in EXPLAIN ANALYZE's
output for index scan/index-only scan/bitmap index scan nodes. This
information is particularly useful with scans that use ScalarArrayOp
quals, where the number of index searches can be unpredictable due to
implementation details that interact with physical index characteristics
(at least with nbtree SAOP scans, since Postgres 17 commit 5bf748b8).
The information shown also provides useful context when EXPLAIN ANALYZE
runs a plan with an index scan node that successfully applied the skip
scan optimization (set to be added to nbtree by an upcoming patch).
The instrumentation works by teaching all index AMs to increment a new
nsearches counter whenever a new index search begins. The counter is
incremented at exactly the same point that index AMs already increment
the pg_stat_*_indexes.idx_scan counter (we're counting the same event,
but at the scan level rather than the relation level). Parallel queries
have workers copy their local counter struct into shared memory when an
index scan node ends -- even when it isn't a parallel aware scan node.
An earlier version of this patch that only worked with parallel aware
scans became commit 5ead85fb (though that was quickly reverted by commit
d00107cd following "debug_parallel_query=regress" buildfarm failures).
Our approach doesn't match the approach used when tracking other index
scan related costs (e.g., "Rows Removed by Filter:"). It is comparable
to the approach used in similar cases involving costs that are only
readily accessible inside an access method, not from the executor proper
(e.g., "Heap Blocks:" output for a Bitmap Heap Scan, which was recently
enhanced to show per-worker costs by commit 5a1e6df3, using essentially
the same scheme as the one used here). It is necessary for index AMs to
have direct responsibility for maintaining the new counter, since the
counter might need to be incremented multiple times per amgettuple call
(or per amgetbitmap call). But it is also necessary for the executor
proper to manage the shared memory now used to transfer each worker's
counter struct to the leader.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Robert Haas <robertmhaas@gmail.com>
Reviewed-By: Tomas Vondra <tomas@vondra.me>
Reviewed-By: Masahiro Ikeda <ikedamsh@oss.nttdata.com>
Reviewed-By: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/CAH2-WzkRqvaqR2CTNqTZP0z6FuL4-3ED6eQB0yx38XBNj1v-4Q@mail.gmail.com
Discussion: https://postgr.es/m/CAH2-Wz=PKR6rB7qbx+Vnd7eqeB5VTcrW=iJvAsTsKbdG+kW_UA@mail.gmail.com
With improperly defined operator classes, it's possible to get a
Postgres crash because we'd try to invoke a procedure that doesn't
exist. This is because the code is being a bit too trusting that the
opclass is correctly defined. Add some ereport(ERROR)s for cases where
mandatory support procedures are not defined, transforming the crashes
into errors.
The particular case that was reported is an incomplete opclass in
PostGIS.
Backpatch all the way down to 13.
Reported-by: Tobias Wendorff <tobias.wendorff@tu-dortmund.de>
Diagnosed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/fb6d9a35-6c8e-4869-af80-0a4944a793a4@tu-dortmund.de
Many STRICT function calls will have one or two arguments, in which
case we can speed up checking for NULL input by avoiding setting up
a loop over the arguments. This adds EEOP_FUNCEXPR_STRICT_1 and the
corresponding EEOP_FUNCEXPR_STRICT_2 for functions with one and two
arguments respectively.
Author: Andres Freund <andres@anarazel.de>
Co-authored-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Andreas Karlsson <andreas@proxel.se>
Discussion: https://postgr.es/m/415721CE-7D2E-4B74-B5D9-1950083BA03E@yesql.se
Discussion: https://postgr.es/m/20191023163849.sosqbfs5yenocez3@alap3.anarazel.de
Knowing when the side-effects of an expression is the intended result
of the execution, rather than the returnvalue, is important for being
able generate more efficient JITed code. This replaces EEOP_DONE with
two new steps: EEOP_DONE_RETURN and EEOP_DONE_NO_RETURN. Expressions
which return a value should use the former step; expressions used for
their side-effects which don't return value should use the latter.
Author: Andres Freund <andres@anarazel.de>
Co-authored-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Andreas Karlsson <andreas@proxel.se>
Discussion: https://postgr.es/m/415721CE-7D2E-4B74-B5D9-1950083BA03E@yesql.se
Discussion: https://postgr.es/m/20191023163849.sosqbfs5yenocez3@alap3.anarazel.de
This change is harmless and does not affect the existing intended
operation. It is necessary for a subsequent patch operation (NOT
ENFORCED foreign keys), where we may need to change the child
constraint to enforced. In this case, we would create the necessary
triggers and queue the constraint for validation, so it is important
to remove any unnecessary constraints before proceeding.
This is a small change that could have been included in the previous
"split tryAttachPartitionForeignKey" refactoring patch (commit
1d26c2d2c4), but was kept separate to highlight the changes.
Author: Amul Sul <amul.sul@enterprisedb.com>
Reviewed-by: Alexandra Wang <alexandra.wang.oss@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAAJ_b962c5AcYW9KUt_R_ER5qs3fUGbe4az-SP-vuwPS-w-AGA%40mail.gmail.com
Split tryAttachPartitionForeignKey() into three functions:
AttachPartitionForeignKey(), RemoveInheritedConstraint(), and
DropForeignKeyConstraintTriggers(), so they can be reused in some
subsequent patches for the NOT ENFORCED feature.
Author: Amul Sul <amul.sul@enterprisedb.com>
Reviewed-by: Alexandra Wang <alexandra.wang.oss@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAAJ_b962c5AcYW9KUt_R_ER5qs3fUGbe4az-SP-vuwPS-w-AGA%40mail.gmail.com
This commit adds per-backend WAL statistics, providing the same
information as pg_stat_wal, except that it is now possible to know how
much WAL activity is happening in each backend rather than an overall
aggregate of all the activity. Like pg_stat_wal, the implementation
relies on pgWalUsage, tracking the difference of activity between two
reports to pgstats.
This data can be retrieved with a new system function called
pg_stat_get_backend_wal(), that returns one tuple based on the PID
provided in input. Like pg_stat_get_backend_io(), this is useful when
joined with pg_stat_activity to get a live picture of the WAL generated
for each running backend, showing how the activity is [un]balanced.
pgstat_flush_backend() gains a new flag value, able to control the flush
of the WAL stats.
This commit relies mostly on the infrastructure provided by
9aea73fc61, that has introduced backend statistics.
Bump catalog version. A bump of PGSTAT_FILE_FORMAT_ID is not required,
as backend stats do not persist on disk.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reviewed-by: Xuneng Zhou <xunengzhou@gmail.com>
Discussion: https://postgr.es/m/Z3zqc4o09dM/Ezyz@ip-10-97-1-34.eu-west-3.compute.internal
This fixes a thinko from commit d611f8b15. The intent was to prevent
updating the stats of the pre-existing heap if autovacuum is off,
but it also disabled updating the stats of the just-created index.
There is AFAICS no good reason to do the latter, since there could not
be any pre-existing stats to refrain from overwriting, and the zeroed
stats that are there to begin with are very unlikely to be useful.
Moreover, the change broke our cross-version upgrade tests again.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/1116282.1741374848@sss.pgh.pa.us
The function calls GetLatestSnapshot() to acquire a fresh snapshot,
makes it active, and was meant to pass it to table_tuple_lock(), but
instead called GetLatestSnapshot() again to acquire yet another
snapshot. It was harmless because the heap AM and all other known
table AMs ignore the 'snapshot' argument anyway, but let's be tidy.
In the long run, this perhaps should be redesigned so that snapshot
was not needed in the first place. The table AM API uses TID +
snapshot as the unique identifier for the row version, which is
questionable when the row came from an index scan with a Dirty
snapshot. You might lock a different row version when you use a
different snapshot in the table_tuple_lock() call (a fresh MVCC
snapshot) than in the index scan (DirtySnapshot). However, in the heap
AM and other AMs where the TID alone identifies the row version, it
doesn't matter. So for now, just fix the obvious albeit harmless bug.
This has been wrong ever since the table AM API was introduced in
commit 5db6df0c01, so backpatch to all supported versions.
Discussion: https://www.postgresql.org/message-id/83d243d6-ad8d-4307-8b51-2ee5844f6230@iki.fi
Backpatch-through: 13
Recognizing the real-life complexity where columns in the table often have
functional dependencies, PostgreSQL's estimation of the number of distinct
values over a set of columns can be underestimated (or much rarely,
overestimated) when dealing with multi-clause JOIN. In the case of hash
join, it can end up with a small number of predicted hash buckets and, as
a result, picking non-optimal merge join.
To improve the situation, we introduce one additional stage of bucket size
estimation - having two or more join clauses estimator lookup for extended
statistics and use it for multicolumn estimation. Clauses are grouped into
lists, each containing expressions referencing the same relation. The result
of the multicolumn estimation made over such a list is combined with others
according to the caller's logic. Clauses that are not estimated are returned
to the caller for further estimation.
Discussion: https://postgr.es/m/52257607-57f6-850d-399a-ec33a654457b%40postgrespro.ru
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Andy Fan <zhihui.fan1213@gmail.com>
Reviewed-by: Tomas Vondra <tomas.vondra@enterprisedb.com>
Reviewed-by: Alena Rybakina <lena.ribackina@yandex.ru>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
This change is dedicated to more active usage of IndexScan and parameterized
NestLoop paths in partitioned cases under an Append node, as it already works
with plain tables. As newly added regression tests demonstrate, it should
provide more smartness to the partitionwise technique.
With an indication of how many tuples are needed, it may be more meaningful
to use the 'fractional branch' subpaths of the Append path list, which are
more optimal for this specific number of tuples. Planning on a higher level,
if the optimizer needs all the tuples, it will choose non-fractional paths.
In the case when, during execution, Append needs to return fewer tuples than
declared by tuple_fraction, it would not be harmful to use the 'intermediate'
variant of paths. However, it will earn a considerable profit if a sensible
set of tuples is selected.
The change of the existing regression test demonstrates the positive outcome
of this feature: instead of scanning the whole table, the optimizer prefers
to use a parameterized scan, being aware of the only single tuple the join
has to produce to perform the query.
Discussion: https://www.postgresql.org/message-id/flat/CAN-LCVPxnWB39CUBTgOQ9O7Dd8DrA_tpT1EY3LNVnUuvAX1NjA%40mail.gmail.com
Author: Nikita Malakhov <hukutoc@gmail.com>
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Andy Fan <zhihuifan1213@163.com>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
It isn't clear how these should behave, so let's wait to implement them
until we are sure how to do it.
This feature was initially added by commit 89f908a6d0, so it hasn't
been released yet.
Author: Paul A. Jungwirth <pj@illuminatedcomputing.com>
Discussion: https://postgr.es/m/e773bc11-4ac1-40de-bb91-814e02f05b6d%40eisentraut.org
This doesn't work because record_recv requires the typmod that
identifies the specific record type (in our session) and
array_agg_deserialize has no convenient way to get that information.
The result is an "input of anonymous composite types is not
implemented" error.
We could probably make this work if we had to, but it does not seem
worth the trouble, given that it took this long to get a field report.
Just shut off parallelization, as though record_recv didn't exist.
Oversight in commit 16fd03e95. Back-patch to v16 where that
came in.
Reported-by: Kirill Zdornyy <kirill@dineserve.com>
Diagnosed-by: Richard Guo <guofenglinux@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/atLI5Kce2ie1zcYjU0w_kjtVaxiYbYGTihrkLDmGZQnRDD4pnXukIATaABbnIj9pUnelC4ESvCXMm4HAyHg-v61XABaKpERj0A2IXzJZM7g=@dineserve.com
Backpatch-through: 16
Per POSIX, a caller of strtol() that wishes to check for errors must
set errno to 0 beforehand. Several places in spell.c neglected that,
so that they risked delivering a false overflow error in case errno
had been ERANGE already. Given the lack of field reports, this case
may be unreachable at present --- but it's surely trouble waiting to
happen, so fix it.
Author: Jacob Brazeal <jacob.brazeal@gmail.com>
Discussion: https://postgr.es/m/CA+COZaBhsq6EromFm+knMJfzK6nTpG23zJ+K2=nfUQQXcj_xcQ@mail.gmail.com
Backpatch-through: 13
Teach parallel nbtree index scans to use an LWLock (not a spinlock) to
protect the scan's shared descriptor state.
Preparation for an upcoming patch that will add skip scan optimizations
to nbtree. That patch will create the need to occasionally allocate
memory while the scan descriptor is locked, while copying datums that
were serialized by another backend.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/CAH2-Wz=PKR6rB7qbx+Vnd7eqeB5VTcrW=iJvAsTsKbdG+kW_UA@mail.gmail.com
The callback pgstat_backend_have_pending_cb() is used as a way for
pg_stat_report() to detect if there is any pending data for backend
statistics.
It did not include a check based on pgstat_tracks_backend_bktype(), that
discards processes whose backend types do not support backend
statistics. The logic is not a problem on HEAD, as processes that do
not support backend statistics cannot touch PendingBackendStats, so the
callback would always report that there is no pending data in this case.
However, we would run into trouble once backend statistics include
portions of pending stats that are not always zeroed, like pgWalUsage.
There is no reason for pgstat_backend_have_pending_cb() to not check
for pgstat_tracks_backend_bktype(), anyway, and this pattern is safer in
the long run, so let's update the code to do so.
While on it, this commit adds a proper initialization to
PendingBackendStats.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Co-authored-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/Z8l6EMM4ImVoWRkg@ip-10-97-1-34.eu-west-3.compute.internal
Formerly we only provided the column number, but it's frequently
more useful to mention the column name. The input tupdesc often
doesn't have useful column names, but the output tupdesc usually
contains user-supplied names, so report that one.
Author: Marcos Pegoraro <marcos@f10.com.br>
Co-authored-by: jian he <jian.universality@gmail.com>
Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us>
Co-authored-by: Erik Wienhold <ewie@ewie.name>
Reviewed-by: Vladlen Popolitov <v.popolitov@postgrespro.ru>
Discussion: https://postgr.es/m/CAB-JLwanky28gjAMdnMh1CjyO1b2zLdr6UOA1-oY9G7PVL9KKQ@mail.gmail.com
Commit ce62f2f2a0 introduced calls to GetIndexAmRoutineByAmId() in
lsyscache.c functions. This call is a bit more expensive than a
simple syscache lookup. So rearrange the nesting so that we call that
one last and do the cheaper checks first.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/E1tngY6-0000UL-2n%40gemulon.postgresql.org
After more discussion about commit ce62f2f2a0, rename the index AM
property amcancrosscompare to two separate properties
amconsistentequality and amconsistentordering. Also improve the
documentation and update some comments that were previously missed.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/E1tngY6-0000UL-2n%40gemulon.postgresql.org
This allows smallint, integer, and bigint values to be cast to and
from bytea. The bytea value is the two's complement representation of
the integer, with the most significant byte first. For example:
1234::bytea -> \x000004d2
(-1234)::bytea -> \xfffffb2e
Author: Aleksander Alekseev <aleksander@timescale.com>
Reviewed-by: Joel Jacobson <joel@compiler.org>
Reviewed-by: Yugo Nagata <nagata@sraoss.co.jp>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Discussion: https://postgr.es/m/CAJ7c6TPtOp6%2BkFX5QX3fH1SVr7v65uHr-7yEJ%3DGMGQi5uhGtcA%40mail.gmail.com
We previously fixed this for binary upgrade in 71b66171d0, but a
similar problem remained when dumping statistics without data.
Fix by not opportunistically updating table stats during CREATE INDEX
when autovacuum is disabled. For stats to be stable at all, the server
needs to be aware that it should not take every opportunity to update
stats. Per discussion, autovacuum=off is a signal that the user
expects stats to be stable; though if necessary, we could create
a more specific mode in the future.
Reported-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: https://postgr.es/m/CAExHW5vf9D+8-a5_BEX3y=2y_xY9hiCxV1=C+FnxDvfprWvkng@mail.gmail.com
Discussion: https://postgr.es/m/ca81cbf6e6ea2af838df972801ad4da52640a503.camel%40j-davis.com
If a GIN index search had a lot of search keys (for example,
"jsonbcol ?| array[]" with tens of thousands of array elements),
both ginFillScanKey() and startScanKey() took O(N^2) time.
Worse, those loops were uncancelable for lack of CHECK_FOR_INTERRUPTS.
The problem in ginFillScanKey() is the brute-force search key
de-duplication done in ginFillScanEntry(). The most expedient
solution seems to be to just stop trying to de-duplicate once
there are "too many" search keys. We could imagine working harder,
say by using a sort-and-unique algorithm instead of brute force
compare-all-the-keys. But it seems unlikely to be worth the trouble.
There is no correctness issue here, since the code already allowed
duplicate keys if any extra_data is present.
The problem in startScanKey() is the loop that attempts to identify
the first non-required search key. In the submitted test case, that
vainly tests all the key positions, and each iteration takes O(N)
time. One part of that is that it's reinitializing the entryRes[]
array from scratch each time, which is entirely unnecessary given
that the triConsistentFn isn't supposed to scribble on its input.
We can easily adjust the array contents incrementally instead.
The other part of it is that the triConsistentFn may itself take
O(N) time (and does in this test case). This is all extremely
brute force: in simple cases with AND or OR semantics, we could
know without any looping whatever that all or none of the keys
are required. But GIN opclasses don't have any API for exposing
that knowledge, so at least in the short run there is little to
be done about that. Put in a CHECK_FOR_INTERRUPTS so that at
least the loop is cancelable.
These two changes together resolve the primary complaint that
the test query doesn't respond promptly to cancel interrupts.
Also, while they don't completely eliminate the O(N^2) behavior,
they do provide quite a nice speedup for mid-sized examples.
Bug: #18831
Reported-by: Niek <niek.brasa@hitachienergy.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18831-e845ac44ebc5dd36@postgresql.org
Backpatch-through: 13
On change of publication via ALTER PUBLICATION ... SET/ADD/DROP commands,
we were invalidating all the relations present in relation sync cache
maintained by pgoutput. We need to invalidate only the relation entries
that are changed as part of publication DDL.
We have ensured that the publication DDL execution generated the
invalidations required to invalidate impacted relation sync entries in
RelationSyncCache.
This improves the performance by avoiding building the cache entries for
the cases where a publication has many tables but only one of them is
dropped.
Author: Shlok Kyal <shlok.kyal.oss@gmail.com>
Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Hou Zhijie <houzj.fnst@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/OSCPR01MB14966C09AA201EFFA706576A7F5C92@OSCPR01MB14966.jpnprd01.prod.outlook.com
This commit adds two improvements related to the monitoring of WAL
writes for the WAL receiver.
First, write counts and timings are now counted in pg_stat_io for the
WAL receiver. These have been discarded from pg_stat_wal in
ff99918c62 due to performance concerns, related to the fact that we
still relied on an on-disk file for the stats back then, even with
track_wal_io_timing to avoid the overhead of the timestamp calculations.
This implementation is simpler than the original proposal as it is
possible to rely on the APIs of pgstat_io.c to do the job. Like the
fsync and read data, track_wal_io_timing needs to be enabled to track
the timings.
Second, a wait event is added around the pg_pwrite() call in charge of
the writes, using the exiting WAIT_EVENT_WAL_WRITE. This is useful as
the WAL receiver data is tracked in pg_stat_activity.
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/Z8gFnH4o3jBm5BRz@ip-10-97-1-34.eu-west-3.compute.internal
This is in preparation for splitting WaitEventSet related functions to
a separate source file. That will hide the details of WaitEventSet
from WaitLatch, so it must use an exposed function instead of
modifying WaitEventSet->exit_on_postmaster_death directly.
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/8a507fb6-df28-49d3-81a5-ede180d7f0fb@iki.fi
This reverts commit 5ead85fbc8.
This commit shows test failures with debug_parallel_query=regress. The
underlying issue needs to be debugged, so revert for now.
An additional paramater ("strip_in_arrays") is added to these functions.
It defaults to false. If true, then null array elements are removed as
well as null valued object fields. JSON that just consists of a single
null is not affected.
Author: Florents Tselai <florents.tselai@gmail.com>
Discussion: https://postgr.es/m/4BCECCD5-4F40-4313-9E98-9E16BEB0B01D@gmail.com
Expose the count of index searches/index descents in EXPLAIN ANALYZE's
output for index scan nodes. This information is particularly useful
with scans that use ScalarArrayOp quals, where the number of index scans
isn't predictable in advance (at least not with optimizations like the
one added to nbtree by Postgres 17 commit 5bf748b8). It will also be
useful when EXPLAIN ANALYZE shows details of an nbtree index scan that
uses skip scan optimizations set to be introduced by an upcoming patch.
The instrumentation works by teaching index AMs to increment a new
nsearches counter whenever a new index search begins. The counter is
incremented at exactly the same point that index AMs must already
increment the index's pg_stat_*_indexes.idx_scan counter (we're counting
the same event, but at the scan level rather than the relation level).
The new counter is stored in the scan descriptor (IndexScanDescData),
which explain.c reaches by going through the scan node's PlanState.
This approach doesn't match the approach used when tracking other index
scan specific costs (e.g., "Rows Removed by Filter:"). It is similar to
the approach used in other cases where we must track costs that are only
readily accessible inside an access method, and not from the executor
(e.g., "Heap Blocks:" output for a Bitmap Heap Scan). It is inherently
necessary to maintain a counter that can be incremented multiple times
during a single amgettuple call (or amgetbitmap call), and directly
exposing PlanState.instrument to index access methods seems unappealing.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Tomas Vondra <tomas@vondra.me>
Reviewed-By: Robert Haas <robertmhaas@gmail.com>
Reviewed-By: Masahiro Ikeda <ikedamsh@oss.nttdata.com>
Reviewed-By: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/CAH2-Wz=PKR6rB7qbx+Vnd7eqeB5VTcrW=iJvAsTsKbdG+kW_UA@mail.gmail.com
Discussion: https://postgr.es/m/CAH2-WzkRqvaqR2CTNqTZP0z6FuL4-3ED6eQB0yx38XBNj1v-4Q@mail.gmail.com
The usual pattern for handling a signal is that the signal handler
sets a flag and calls SetLatch(MyLatch), and CHECK_FOR_INTERRUPTS() or
other code that is part of a wait loop calls another function to deal
with it. The naming of the functions involved was a bit inconsistent,
however. CHECK_FOR_INTERRUPTS() calls ProcessInterrupts() to do the
heavy-lifting, but the analogous functions in aux processes were
called HandleMainLoopInterrupts(), HandleStartupProcInterrupts(),
etc. Similarly, most subroutines of ProcessInterrupts() were called
Process*(), but some were called Handle*().
To make things less confusing, rename all the functions that are part
of the overall signal/interrupt handling system but are not executed
in a signal handler to e.g. ProcessSomething(), rather than
HandleSomething(). The "Process" prefix is now consistently used in
the non-signal-handler functions, and the "Handle" prefix in functions
that are part of signal handlers, except for some completely unrelated
functions that clearly have nothing to do with signal or interrupt
handling.
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://www.postgresql.org/message-id/8a384b26-1499-41f6-be33-64b801fb98b8@iki.fi
This allows to redefine an existing non-inheritable constraint to be
inheritable, which allows to straighten up situations with NO INHERIT
constraints so that thay can become normal constraints without having to
re-verify existing data. For existing inheritance children this may
require creating additional constraints, if they don't exist already.
It also allows to do the opposite, if only for symmetry.
Author: Suraj Kharage <suraj.kharage@enterprisedb.com>
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://postgr.es/m/CAF1DzPVfOW6Kk=7SSh7LbneQDJWh=PbJrEC_Wkzc24tHOyQWGg@mail.gmail.com
The WAL receiver and WAL summarizer processes gain each one a call to
pgstat_report_wal(), to make sure that they report their WAL statistics
to pgstats, gathering data for pg_stat_io.
In the WAL receiver, the stats reports are timed with status updates sent
to the primary, that depend on wal_receiver_status_interval and
wal_receiver_timeout. This is a conservative choice, but perhaps we
could be more aggressive with the frequency of the stats reports. An
interesting historical fact is that the WAL receiver does writes and
syncs of WAL, but it has never reported its statistics to pgstats in
pg_stat_wal.
In the WAL summarizer, the stats reports are done each time the process
waits for WAL.
While on it, pg_stat_io is adjusted so as these two processes do not
report any rows when IOObject is not WAL, making the view easier to use
with less rows.
Two tests are added in TAP, checking statistics for the WAL summarizer
and the WAL receiver. Status updates in the WAL receiver are currently
possible in the recovery test 001_stream_rep.pl.
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/Z8UKZyVSHUUQJHNb@paquier.xyz
Index builds are expected to respect maintenance_work_mem, just like
other maintenance operations. For serial builds this is done simply by
flushing the buffer in ginBuildCallback() into the index. But with
parallel builds it's more complicated, because there are multiple places
that can allocate memory.
ginBuildCallbackParallel() does the same thing as ginBuildCallback(),
except that the accumulated items are written into tuplesort. Then the
entries with the same key get merged - first in the worker, then in the
leader - and the TID lists may get (arbitrarily) long. It's unlikely it
would exceed the memory limit, but it's possible. We address this by
evicting some of the data if the list gets too long.
We can't simply dump the whole in-memory TID list. The GIN index bulk
insert code expects to see TIDs in monotonic order; it may fail if the
TIDs go backwards. If the TID lists overlap, evicting the whole current
TID list would break this (a later entry might add "old" TID values into
the already-written part).
In the workers this is not an issue, because the lists never overlap.
But the leader may see overlapping lists produced by the workers.
We can however derive a safe "horizon" TID - the entries (for a given
key) are sorted by (key, first TID), which means no future list can add
values before the last "first TID" we've seen. This patch tracks the
"frozen" part of the TID list, which we know can't change by merging
additional TID lists. If needed, we can evict this part of the list.
We don't want to do this too often - the smaller lists we evict, the
more expensive it'll be to merge them in the next step (especially in
the leader). Therefore we only trim the list if we have at least 1024
frozen items, and if the whole list is at least 64kB large.
These thresholds are somewhat arbitrary and conservative. We might
calculate the values from maintenance_work_mem, but tests show that does
not really improve anything (time, compression ratio, ...). So we stick
to these conservative values to release memory faster.
Author: Tomas Vondra
Reviewed-by: Matthias van de Meent, Andy Fan, Kirill Reshke
Discussion: https://postgr.es/m/6ab4003f-a8b8-4d75-a67f-f25ad98582dc%40enterprisedb.com
This bogus error message was introduced in 2013 by commit f177cbfe67,
because of misunderstanding the processCASbits() API; at the time, no
test cases were added that would be affected by this change. Only in
ca87c415e2 was one added (along with a couple of typos), with an XXX
note that the error message was bogus. Fix the whole, add some test
cases.
Backpatch all the way back.
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/202503041822.aobpqke3igvb@alvherre.pgsql
The change improves efficiency by eliminating unnecessary copying of
CopyFormatOptions.
The coverity also complained about inefficiencies caused by
pass-by-value.
Oversight in 7717f6300 and 2e4127b6d.
Reported-by: Junwang Zhao <zhjwpku@gmail.com>
Reported-by: Tom Lane <tgl@sss.pgh.pa.us> (per reports from coverity)
Author: Sutou Kouhei <kou@clear-code.com>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/CAEG8a3L6YCpPksTQMzjD_CvwDEhW3D_t=5md9BvvdOs5k+TA=Q@mail.gmail.com
When serializing GIN tuples to tuplesorts during parallel index builds,
we can significantly reduce the amount of data by compressing the TID
lists. The GIN opclasses may produce a lot of data (depending on how
many keys are extracted from each row), and the TID compression is very
efficient and effective.
If the number of distinct keys is high, the first worker pass (reading
data from the table and writing them into a private tuplesort) may not
benefit from the compression very much. It is likely to spill data to
disk before the TID lists get long enough for the compression to help.
The second pass (writing the merged data into the shared tuplesort) is
more likely to benefit from compression.
The compression can be seen as a way to reduce the amount of disk space
needed by the parallel builds, because the data is written twice. First
into the per-worker tuplesorts, then into the shared tuplesort.
Author: Tomas Vondra
Reviewed-by: Matthias van de Meent, Andy Fan, Kirill Reshke
Discussion: https://postgr.es/m/6ab4003f-a8b8-4d75-a67f-f25ad98582dc%40enterprisedb.com
The FP_LOCK_SLOTS_PER_BACKEND macro looks like a constant, but it
depends on the max_locks_per_transaction GUC, and thus can change. This
is non-obvious and confusing, so make it look more like a function by
renaming it to FastPathLockSlotsPerBackend().
While at it, use the macro when initializing fast-path shared memory,
instead of using the formula.
Reported-by: Andres Freund
Discussion: https://postgr.es/m/ffiwtzc6vedo6wb4gbwelon5nefqg675t5c7an2ta7pcz646cg%40qwmkdb3l4ett
Commit bc971f4025 replaced the latch-setting mechanism that the
comment talked about with a condition variable. And before that,
commit 2258e76f90 moved the code so that the comment got detached from
the loop that it talked about, so move the comment closer to the loop.
demo:
CREATE TABLE gtest20a (a int PRIMARY KEY, b int GENERATED ALWAYS AS (a * 2) VIRTUAL);
ALTER TABLE gtest20a ADD COLUMN c float8 DEFAULT RANDOM() CHECK (b < 60);
ERROR: no generation expression found for column number 2 of table "pg_temp_17306"
In ATRewriteTable, the variable OIDNewHeap (if valid) corresponding
pg_attrdef default expression entry was not populated. So OIDNewHeap
cannot be used to call expand_generated_columns_in_expr or
build_generation_expression. Therefore in ATRewriteTable, we can only
use the existing relation to expand the generated expression.
Author: jian he <jian.universality@gmail.com>
Reviewed-by: Srinath Reddy <srinath2133@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CACJufxEJ%3DFoajabWXjszo_yrQeKSxdZ87KJqBW373rSbajKGAA%40mail.gmail.com
In commit b262ad440, we introduced an optimization that reduces an IS
NOT NULL qual on a column defined as NOT NULL to constant true, and an
IS NULL qual on a NOT NULL column to constant false, provided we can
prove that the input expression of the NullTest is not nullable by any
outer join. This deduction happens after we have generated multiple
clones of the same qual condition to cope with commuted-left-join
cases.
However, performing the NullTest deduction for clone clauses can be
unsafe, because we don't have a reliable way to determine if the input
expression of a NullTest is non-nullable: nullingrel bits in clone
clauses may not reflect reality, so we dare not draw conclusions from
clones about whether Vars are guaranteed not-null.
To fix, we check whether the given RestrictInfo is a clone clause in
restriction_is_always_true and restriction_is_always_false, and avoid
performing any reduction if it is.
There are several ensuing plan changes in predicate.out, and we have
to modify the tests to ensure that they continue to test what they are
intended to. Additionally, this fix causes the test case added in
f00ab1fd1 to no longer trigger the bug that commit fixed, so we also
remove that test case.
Back-patch to v17 where this bug crept in.
Reported-by: Ronald Cruz <cruz@rentec.com>
Diagnosed-by: Tom Lane <tgl@sss.pgh.pa.us>
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/f5320d3d-77af-4ce8-b9c3-4715ff33f213@rentec.com
Backpatch-through: 17
pgstat_bestart(), used post-authentication to set up a backend entry
in the PgBackendStatus array, so as its data becomes visible in
pg_stat_activity and related catalogs, has its logic divided into three
routines with this commit, called in order at different steps of the
backend initialization:
* pgstat_bestart_initial() sets up the backend entry with a minimal
amount of information, reporting it with a new BackendState called
STATE_STARTING while waiting for backend initialization and client
authentication to complete. The main benefit that this offers is
observability, so as it is possible to monitor the backend activity
during authentication. This step happens earlier than in the logic
prior to this commit. pgstat_beinit() happens earlier as well, before
authentication.
* pgstat_bestart_security() reports the SSL/GSS status of the
connection, once authentication completes. Auxiliary processes, for
example, do not need to call this step, hence it is optional. This
step is called after performing authentication, same as previously.
* pgstat_bestart_final() reports the user and database IDs, takes the
entry out of STATE_STARTING, and reports its application_name. This is
called as the last step of the three, once authentication completes.
An injection point is added, with a test checking that the "starting"
phase of a backend entry is visible in pg_stat_activity. Some follow-up
patches are planned to take advantage of this refactoring with more
information provided in backend entries during authentication (LDAP
hanging was a problem for the author, initially).
Author: Jacob Champion <jacob.champion@enterprisedb.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CAOYmi+=60deN20WDyCoHCiecgivJxr=98s7s7-C8SkXwrCfHXg@mail.gmail.com
palloc() includes an assertion checking that an alloc() implementation
never returns NULL for all MemoryContextMethods.
This commit adds a similar assertion in palloc0(). In palloc_extend(),
a different assertion is added, checking that MCXT_ALLOC_NO_OOM is set
when an alloc() routine returns NULL. These additions can be useful to
catch errors when implementing a new set of MemoryContextMethods
routines.
Author: Andreas Karlsson <andreas@proxel.se>
Discussion: https://postgr.es/m/507e8eba-2035-4a12-a777-98199a66beb8@proxel.se
Calculate the insert threshold for triggering an autovacuum of a
relation based on the number of unfrozen pages.
By only considering the unfrozen portion of the table when calculating
how many tuples to add to the insert threshold, we can trigger more
frequent vacuums of insert-heavy tables. This increases the chances of
vacuuming those pages when they still reside in shared buffers
This also increases the number of autovacuums triggered by tuples
inserted and not by wraparound risk. We prefer to freeze these pages
during insert-triggered autovacuums, as anti-wraparound vacuums are not
automatically canceled by conflicting lock requests.
We calculate the unfrozen percentage of the table using the recently
added (99f8f3fbbc) relallfrozen column of pg_class.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Greg Sabino Mullane <htamfids@gmail.com>
Reviewed-by: Robert Treat <rob@xzilla.net>
Reviewed-by: wenhui qiu <qiuwenhuifx@gmail.com>
Discussion: https://postgr.es/m/flat/CAAKRu_aj-P7YyBz_cPNwztz6ohP%2BvWis%3Diz3YcomkB3NpYA--w%40mail.gmail.com
DefineRelation was of the opinion that it could usefully pre-fill
atthasdef flags to eliminate work for StoreAttrDefault. This is not
the case, however: the tupledesc that it's filling is not the one that
InsertPgAttributeTuples will work from. The tupledesc used there is
made by RelationBuildLocalRelation, which deliberately doesn't copy
atthasdef. Moreover, if this did happen as the code thinks, it would
be wrong for the case of plain "DEFAULT NULL" clauses, since we detect
and ignore simple-null-Const defaults later on. Hence, remove the
useless code.
It also emerges that it's not really worth a special-case path in
StoreAttrDefault() for atthasdef already being set, because as far as
we can see that never happens: cases where an existing default gets
updated always do RemoveAttrDefault first, so as to clean up
possibly-no-longer-correct dependency entries. If it were the case
the code would still work, anyway.
Also remove a nearby comment made moot by 5eaa0e92e.
Author: jian he <jian.universality@gmail.com>
Discussion: https://postgr.es/m/CACJufxHFssPvkP1we7WMhPD_1kwgbG52o=kQgL+TnVoX5LOyCQ@mail.gmail.com
StoreAttrDefault() is no longer responsible for filling
attmissingval, so remove the code for that.
Get rid of RawColumnDefault.missingMode, too, as we no longer
need that to pass information around.
While here, clean up some sloppy coding in StoreAttrDefault(),
such as failure to use XXXGetDatum macros. These aren't bugs
but they're not good code either.
Reported-by: jian he <jian.universality@gmail.com>
Author: jian he <jian.universality@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CACJufxHFssPvkP1we7WMhPD_1kwgbG52o=kQgL+TnVoX5LOyCQ@mail.gmail.com
If a domain type has a default, adding a column of that type (without
any explicit DEFAULT clause) failed to install the domain's default
value in existing rows, instead leaving the new column null. This
is unexpected, and it used to work correctly before v11. The cause
is confusion in the atthasmissing mechanism about which default value
to install: we'd only consider installing an explicitly-specified
default, and then we'd decide that no table rewrite is needed.
To fix, take the responsibility for filling attmissingval out of
StoreAttrDefault, and instead put it into ATExecAddColumn's existing
logic that derives the correct value to fill the new column with.
Also, centralize the logic that determines the need for
default-related table rewriting there, instead of spreading it over
four or five places.
In the back branches, we'll leave the attmissingval-filling code
in StoreAttrDefault even though it's now dead, for fear that some
extension may be depending on that functionality to exist there.
A separate HEAD-only patch will clean up the now-useless code.
Reported-by: jian he <jian.universality@gmail.com>
Author: jian he <jian.universality@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CACJufxHFssPvkP1we7WMhPD_1kwgbG52o=kQgL+TnVoX5LOyCQ@mail.gmail.com
Backpatch-through: 13
Add relallfrozen, an estimate of the number of pages marked all-frozen
in the visibility map.
pg_class already has relallvisible, an estimate of the number of pages
in the relation marked all-visible in the visibility map. This is used
primarily for planning.
relallfrozen, together with relallvisible, is useful for estimating the
outstanding number of all-visible but not all-frozen pages in the
relation for the purposes of scheduling manual VACUUMs and tuning vacuum
freeze parameters.
A future commit will use relallfrozen to trigger more frequent vacuums
on insert-focused workloads with significant volume of frozen data.
Bump catalog version
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Robert Treat <rob@xzilla.net>
Reviewed-by: Corey Huinker <corey.huinker@gmail.com>
Reviewed-by: Greg Sabino Mullane <htamfids@gmail.com>
Discussion: https://postgr.es/m/flat/CAAKRu_aj-P7YyBz_cPNwztz6ohP%2BvWis%3Diz3YcomkB3NpYA--w%40mail.gmail.com
Allow using parallel workers to build a GIN index, similarly to BTREE
and BRIN. For large tables this may result in significant speedup when
the build is CPU-bound.
The work is divided so that each worker builds index entries on a subset
of the table, determined by the regular parallel scan used to read the
data. Each worker uses a local tuplesort to sort and merge the entries
for the same key. The TID lists do not overlap (for a given key), which
means the merge sort simply concatenates the two lists. The merged
entries are written into a shared tuplesort for the leader.
The leader needs to merge the sorted entries again, before writing them
into the index. But this way a significant part of the work happens in
the workers, and the leader is left with merging fewer large entries,
which is more efficient.
Most of the parallelism infrastructure is a simplified copy of the code
used by BTREE indexes, omitting the parts irrelevant for GIN indexes
(e.g. uniqueness checks).
Original patch by me, with reviews and substantial improvements by
Matthias van de Meent, certainly enough to make him a co-author.
Author: Tomas Vondra, Matthias van de Meent
Reviewed-by: Matthias van de Meent, Andy Fan, Kirill Reshke
Discussion: https://postgr.es/m/6ab4003f-a8b8-4d75-a67f-f25ad98582dc%40enterprisedb.com
This commit impacts the following SQL functions, authorizing the access
to the PGPROC entries of auxiliary processes when attempting to fetch or
reset backend-level pgstats entries:
- pg_stat_reset_backend_stats()
- pg_stat_get_backend_io()
This is relevant since a051e71e28 for at least the WAL summarizer, WAL
receiver and WAL writer processes, that has changed the backend
statistics to authorize these three following the addition of WAL I/O
statistics in pg_stat_io and backend statistics. The code is more
flexible with future changes written this way, adapting automatically to
any updates done in pgstat_tracks_backend_bktype().
While on it, pgstat_report_wal() gains a call to pgstat_flush_backend(),
making sure that backend I/O statistics are updated when calling this
routine. This makes the statistics report correctly for the WAL writer.
WAL receiver and WAL summarizer do not call pgstat_report_wal() yet
(spoiler: both should). It should be possible to lift some of the
existing restrictions for other auxiliary processes, as well, but this
is left as future work.
Reported-by: Rahila Syed <rahilasyed90@gmail.com>
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/CAH2L28v9BwN8_y0k6FQ591=0g2Hj_esHLGj3bP38c9nmVykoiA@mail.gmail.com
Commit 7717f63006 removed NextCopyFromRawFields() from copy.h. While
it was hoped that NextCopyFrom() could serve as an alternative,
certain use cases still require NextCopyFromRawFields(). For instance,
extensions like file_text_array_fdw, which process source data with an
unknown number of columns, rely on this function.
Per buildfarm member crake.
Reported-by: Andrew Dunstan <andrew@dunslane.net>
Reviewed-by: Andrew Dunstan <andrew@dunslane.net>
Reviewed-by: Sutou Kouhei <kou@clear-code.com>
Discussion: https://postgr.es/m/5c7e1ac8-5083-4c08-af19-cb9ade2f16ce@dunslane.net
This commit introduces a new CopyFromRoutine struct, which is a set of
callback routines to read tuples in a specific format. It also makes
COPY FROM with the existing formats (text, CSV, and binary) utilize
these format callbacks.
This change is a preliminary step towards making the COPY FROM command
extensible in terms of input formats.
Similar to 2e4127b6d2, this refactoring contributes to a performance
improvement by reducing the number of "if" branches that need to be
checked on a per-row basis when sending field representations in text
or CSV mode. The performance benchmark results showed ~5% performance
gain in text or CSV mode.
Author: Sutou Kouhei <kou@clear-code.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Tomas Vondra <tomas.vondra@enterprisedb.com>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Discussion: https://postgr.es/m/20231204.153548.2126325458835528809.kou@clear-code.com
As per a suggestion from Tom Lane, we do this by declaring "struct
ExplainState" here and refer to that rather than "ExplainState".
Also per Tom, CreateExplainSerializeDestReceiver was still defined
in explain.h in addition to explain_dr.h. Remove leftover prototype.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: http://postgr.es/m/CA+TgmoYtaad3i21V0jqua-fbr+CR0ix6uBvEX8_s6BG96abd=g@mail.gmail.com
Commit ddb17e387a introduced this
regression. Ideally, the regression tests would have caught this
mistake, but apparently they don't test with timing enabled,
presumably because that would make the output vary.
Author: Thom Brown <thom@linux.com>
Reviewed-by: Fabrízio de Royes Mello <fabriziomello@gmail.com>
Discussion: http://postgr.es/m/CAA-aLv6nq=UeiyvM7_Mxgo9TVBzs2oh46b9vfyLzuyVEz3j1-g@mail.gmail.com
This code is extracted from pg_stat_get_backend_io() in pgstatfuncs.c,
so as it can be shared with other areas that need backend pgstats
entries while having the benefits of the various sanity checks
refactored here. As per its name, this retrieves backend statistics
based on a PID, with the option of retrieving a BackendType if given in
input.
Currently, this is used for the backend-level IO statistics. The next
move would be to reuse that for the backend-level WAL statistics.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/Z3zqc4o09dM/Ezyz@ip-10-97-1-34.eu-west-3.compute.internal
This commit introduces a new CopyToRoutine struct, which is a set of
callback routines to copy tuples in a specific format. It also makes
the existing formats (text, CSV, and binary) utilize these format
callbacks.
This change is a preliminary step towards making the COPY TO command
extensible in terms of output formats.
Additionally, this refactoring contributes to a performance
improvement by reducing the number of "if" branches that need to be
checked on a per-row basis when sending field representations in text
or CSV mode. The performance benchmark results showed ~5% performance
gain in text or CSV mode.
Author: Sutou Kouhei <kou@clear-code.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Tomas Vondra <tomas.vondra@enterprisedb.com>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Discussion: https://postgr.es/m/20231204.153548.2126325458835528809.kou@clear-code.com
explain.c has grown rather large, and the code that deals with the
DestReceiver that supports the SERIALIZE option is pretty easily severable
from the rest of explain.c; hence, move it to a separate file.
Reviewed-by: Peter Geoghegan <pg@bowt.ie>
Discussion: http://postgr.es/m/CA+TgmoYutMw1Jgo8BWUmB3TqnOhsEAJiYO=rOQufF4gPLWmkLQ@mail.gmail.com
explain.c has grown rather large, so move various functions that
are principally concerned with output generation to a new source
file, explain_format.c, instead of lumping them in with everything
else that is part of explain.c
Reviewed-by: Peter Geoghegan <pg@bowt.ie>
Discussion: http://postgr.es/m/CA+TgmoYutMw1Jgo8BWUmB3TqnOhsEAJiYO=rOQufF4gPLWmkLQ@mail.gmail.com
Commit ddb17e387a attempted to avoid
confusing users by displaying digits after the decimal point only when
nloops > 1, since it's impossible to have a fraction row count after a
single iteration. However, this made the regression tests unstable since
parallal queries will have nloops>1 for all nodes below the Gather or
Gather Merge in normal cases, but if the workers don't start in time and
the leader finishes all the work, they will suddenly have nloops==1,
making it unpredictable whether the digits after the decimal point would
be displayed or not. Although 44cbba9a7f
seemed to fix the immediate failures, it may still be the case that there
are lower-probability failures elsewhere in the regression tests.
Various fixes are possible here. For example, it has previously been
proposed that we should try to display the digits after the decimal
point only if rows/nloops is an integer, but currently rows is storead
as a float so it's not theoretically an exact quantity -- precision
could be lost in extreme cases. It has also been proposed that we
should try to display the digits after the decimal point only if we're
under some sort of construct that could potentially cause looping
regardless of whether it actually does. While such ideas are not
without merit, this patch adopts the much simpler solution of always
display two decimal digits. If that approach stands up to scrutiny
from the buildfarm and human users, it spares us the trouble of doing
anything more complex; if not, we can reassess.
This commit incidentally reverts 44cbba9a7f,
which should no longer be needed.
Author: Robert Haas <robertmhaas@gmail.com>
Author: Ilia Evdokimov <ilya.evdokimov@tantorlabs.com>
Discussion: http://postgr.es/m/CA+TgmoazzVHn8sFOMFAEwoqBTDxKT45D7mvkyeHgqtoD2cn58Q@mail.gmail.com
Stop comparing access method OID values against HASH_AM_OID and
BTREE_AM_OID, and instead check the IndexAmRoutine for an index to see
if it advertises its ability to perform the necessary ordering,
hashing, or cross-type comparing functionality. A field amcanorder
already existed, this uses it more widely. Fields amcanhash and
amcancrosscompare are added for the other purposes.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
As spotted by Coverity, the calculation of ojrelid mixes signed and unsigned
types causes possible overflow and undefined behavior. Instead of trying to
fix the expression, this commit eliminates the relied local variable. The
explicit branching is used to replace the -1 value. That, in turn, requires
changing the signature of the remove_rel_from_eclass() function.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/914330.1740330169%40sss.pgh.pa.us
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Previously the internal queue of buffers was capped at max_ios * 4,
though not less than io_combine_limit, at allocation time. That was
done in the first version based on conservative theories about resource
usage and heuristics pending later work. The configured I/O depth could
not always be reached with dense random streams generated by ANALYZE,
VACUUM, the proposed Bitmap Heap Scan patch, and also sequential streams
with the proposed AIO subsystem to name some examples.
The new formula is (max_ios + 1) * io_combine_limit, enough buffers for
the full configured I/O concurrency level using the full configured I/O
combine size, plus the buffers from one finished but not yet consumed
full-sized I/O. Significantly more memory would be needed for high GUC
values if the client code requests a large per-buffer data size, but
that is discouraged (existing and proposed stream users try to keep it
under a few words, if not zero).
With this new formula, an intermediate variable could have overflowed
under maximum GUC values, so its data type is adjusted to cope.
Discussion: https://postgr.es/m/CA%2BhUKGK_%3D4CVmMHvsHjOVrK6t4F%3DLBpFzsrr3R%2BaJYN8kcTfWg%40mail.gmail.com
After commit f41d8468dd, a process could acquire and use a replication
slot that had just been invalidated, leading to failures while accessing
WAL.
To ensure that we don't accidentally start using invalid slots, we must
perform the invalidation check after acquiring the slot or under the
spinlock where we associate the slot with a particular process. We choose
the earlier method to keep the code simple.
Reported-by: Hou Zhijie <houzj.fnst@fujitsu.com>
Author: Nisha Moond <nisha.moond412@gmail.com>
Reviewed-by: Hou Zhijie <houzj.fnst@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/CABdArM7J-LbGoMPGUPiFiLOyB_TZ5+YaZb=HMES0mQqzVTn8Gg@mail.gmail.com
This commit adds to pgstatfuncs.c a new routine called
pg_stat_wal_build_tuple(), helper routine for pg_stat_get_wal(). This
is in charge of filling one tuple based on the contents of
PgStat_WalStats retrieved from pgstats.
This refactoring will be used by an upcoming patch introducing
backend-level WAL statistics, simplifying the main patch. Note that
it is not possible for stats_reset to be NULL in pg_stat_wal; backend
statistics need to be able to handle this case.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/Z3zqc4o09dM/Ezyz@ip-10-97-1-34.eu-west-3.compute.internal
9d9b9d46f3 has added spinlocks to protect the fields in ProcSignal
flags, introducing a code path in ProcSignalInit() where a spinlock
could be released twice if the pss_pid field of a ProcSignalSlot is
found as already set. Multiple spinlock releases have no effect with
most spinlock implementations, but this could cause the code to run into
issues when the spinlock is acquired concurrently by a different
process.
This sanity check on pss_pid generates a LOG that can be delayed until
after the spinlock is released as, like older versions up to v17, the
code expects the initialization of the ProcSignalSlot to happen even if
pss_pid is found incorrect. The code is changed so as the old pss_pid
is read while holding the slot's spinlock, with the LOG from the sanity
check generated after releasing the spinlock, preventing the double
release.
Author: Maksim Melnikov <m.melnikov@postgrespro.ru>
Co-authored-by: Maxim Orlov <orlovmg@gmail.com>
Reviewed-by: Andrey Borodin <x4mmm@yandex-team.ru>
Discussion: https://postgr.es/m/dca47527-2d8b-4e3b-b5a0-e2deb73371a4@postgrespro.ru
Previously we used attname for both table and index columns, but
that is problematic for indexes because their attnames are assigned
by internal rules that don't guarantee to preserve the names across
dump and reload. (This is what's causing the remaining buildfarm
failures in cross-version-upgrade tests.) Fortunately we can use
attnum instead, since there's no such thing as adding or dropping
columns in an existing index. We met this same problem previously
with ALTER INDEX ... SET STATISTICS, and solved it the same way,
cf commit 5b6d13eec.
In pg_restore_attribute_stats() itself, we accept either attnum or
attname, but the policy used by pg_dump is to always use attname
for tables and attnum for indexes.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Author: Corey Huinker <corey.huinker@gmail.com>
Discussion: https://postgr.es/m/1457469.1740419458@sss.pgh.pa.us
This new structure contains the counters and the data related to the WAL
activity statistics gathered from WalUsage, separated into its own
structure so as it can be shared across more than one Stats structure in
pg_stat.h.
This refactoring will be used by an upcoming patch introducing
backend-level WAL statistics.
Bump PGSTAT_FILE_FORMAT_ID.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/Z3zqc4o09dM/Ezyz@ip-10-97-1-34.eu-west-3.compute.internal
All the processes that generate WAL should call pgstat_report_wal() to
report all their statistics related to WAL, and this is already what
happens in the tree. Keeping pgstat_report_wal() is confusing while the
other routine is encouraged.
This routine is not required since fc415edf8c, where it was lastly
used in pgstat_report_stat() before an equivalent callback existed.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/Z71oPkJJICrRB5Ws@paquier.xyz
The original message did not mention where the checkpoint record LSN was
found, a control file or a backup_label file. A couple of LOG messages
are generated before this FATAL check is reached, providing more details
about the way recovery is set up. However, knowing this information in
this specific message is useful for debugging. This is also useful for
instances where log_min_messages is set to FATAL or more, where LOG
messages do not show up.
Author: Benoit Lobréau <benoit.lobreau@dalibo.com>
Reviewed-by: David Steele <david@pgbackrest.org>
Discussion: https://postgr.es/m/4ed10bc8-5513-4d8e-8643-8abcaa08336d@dalibo.com
This commit is a rework of 2421e9a51d, about which Andres Freund has
raised some concerns as it is valuable to have both track_io_timing and
track_wal_io_timing in some cases, as the WAL write and fsync paths can
be a major bottleneck for some workloads. Hence, it can be relevant to
not calculate the WAL timings in environments where pg_test_timing
performs poorly while capturing some IO data under track_io_timing for
the non-WAL IO paths. The opposite can be also true: it should be
possible to disable the non-WAL timings and enable the WAL timings (the
previous GUC setups allowed this possibility).
track_wal_io_timing is added back in this commit, controlling if WAL
timings should be calculated in pg_stat_io for the read, fsync and write
paths, as done previously with pg_stat_wal. pg_stat_wal previously
tracked only the sync and write parts (now removed), read stats is new
data tracked in pg_stat_io, all three are aggregated if
track_wal_io_timing is enabled. The read part matters during recovery
or if a XLogReader is used.
Extra note: more control over if the types of timings calculated in
pg_stat_io could be done with a GUC that lists pairs of (IOObject,IOOp).
Reported-by: Andres Freund <andres@anarazel.de>
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Co-authored-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/3opf2wh2oljco6ldyqf7ukabw3jijnnhno6fjb4mlu6civ5h24@fcwmhsgmlmzu
After commit f3dae2ae58, the primary purpose of separating the
pg_set_*_stats() from the pg_restore_*_stats() variants was
eliminated.
Leave pg_restore_relation_stats() and pg_restore_attribute_stats(),
which satisfy both purposes, and remove pg_set_relation_stats() and
pg_set_attribute_stats().
Reviewed-by: Corey Huinker <corey.huinker@gmail.com>
Discussion: https://postgr.es/m/1457469.1740419458@sss.pgh.pa.us
This basically mirrors the changes done in the predecessor commit. While there
isn't currently a need to get these paths in critical sections, it seems a
shame to unnecessarily allocate memory in these paths now that relpath()
doesn't allocate anymore.
Discussion: https://postgr.es/m/xeri5mla4b5syjd5a25nok5iez2kr3bm26j2qn4u7okzof2bmf@kwdh2vf7npra
For AIO, and also some other recent patches, we need the ability to call
relpath() in a critical section. Until now that was not feasible, as it
allocated memory.
The fact that relpath() allocated memory also made it awkward to use in log
messages because we had to take care to free the memory afterwards. Which we
e.g. didn't do for when zeroing out an invalid buffer.
We discussed other solutions, e.g. filling a pre-allocated buffer that's
passed to relpath(), but they all came with plenty downsides or were larger
projects. The easiest fix seems to be to make relpath() return the path by
value.
To be able to return the path by value we need to determine the maximum length
of a relation path. This patch adds a long #define that computes the exact
maximum, which is verified to be correct in a regression test.
As this change the signature of relpath(), extensions using it will need to
adapt their code. We discussed leaving a backward-compat shim in place, but
decided it's not worth it given the use of relpath() doesn't seem widespread.
Discussion: https://postgr.es/m/xeri5mla4b5syjd5a25nok5iez2kr3bm26j2qn4u7okzof2bmf@kwdh2vf7npra
The callback functions ReplaceVarsFromTargetList_callback and
pullup_replace_vars_callback are both used to replace Vars in an
expression tree that reference a particular RTE with items from a
targetlist, and they both need to expand whole-tuple references and
deal with OLD/NEW RETURNING list Vars. As a result, currently there
is significant code duplication between these two functions.
This patch introduces a new function, ReplaceVarFromTargetList, to
perform the replacement and calls it from both callback functions,
thereby eliminating code duplication.
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Jian He <jian.universality@gmail.com>
Discussion: https://postgr.es/m/CAEZATCWhr=FM4X5kCPvVs-g2XEk+ceLsNtBK_zZMkqFn9vUjsw@mail.gmail.com
Commit 83ea6c540 added support for virtual generated columns that are
computed on read. All Var nodes in the query that reference virtual
generated columns must be replaced with the corresponding generation
expressions. Currently, this replacement occurs in the rewriter.
However, this approach has several issues. If a Var referencing a
virtual generated column has any varnullingrels, those varnullingrels
need to be propagated into the generation expression. Failing to do
so can lead to "wrong varnullingrels" errors and improper outer-join
removal.
Additionally, if such a Var comes from the nullable side of an outer
join, we may need to wrap the generation expression in a
PlaceHolderVar to ensure that it is evaluated at the right place and
hence is forced to null when the outer join should do so. In certain
cases, such as when the query uses grouping sets, we also need a
PlaceHolderVar for anything that is not a simple Var to isolate
subexpressions. Failure to do so can result in incorrect results.
To fix these issues, this patch expands the virtual generated columns
in the planner rather than in the rewriter, and leverages the
pullup_replace_vars architecture to avoid code duplication. The
generation expressions will be correctly marked with nullingrel bits
and wrapped in PlaceHolderVars when needed by the pullup_replace_vars
callback function. This requires handling the OLD/NEW RETURNING list
Vars in pullup_replace_vars_callback, as it may now deal with Vars
referencing the result relation instead of a subquery.
The "wrong varnullingrels" error was reported by Alexander Lakhin.
The incorrect result issue and the improper outer-join removal issue
were reported by Richard Guo.
Author: Richard Guo <guofenglinux@gmail.com>
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
Reviewed-by: Jian He <jian.universality@gmail.com>
Discussion: https://postgr.es/m/75eb1a6f-d59f-42e6-8a78-124ee808cda7@gmail.com
This commit documents that the failover option is not copied when using
the pg_copy_logical_replication_slot function.
In passing, we modify the comments in the function clarifying the reason
for this behavior.
Reported-by: <duffieldzane@gmail.com>
Author: Hou Zhijie <houzj.fnst@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 17, where it was introduced
Discussion: https://postgr.es/m/173976850802.682632.11315364077431550250@wrigleys.postgresql.org
A non-leaf partition with a subplan that is an Append node was
omitted from PlannedStmt.unprunableRelids because it was mistakenly
included in PlannerGlobal.prunableRelids due to the way
PartitionedRelPruneInfo.leafpart_rti_map[] is constructed. This
happened when a non-leaf partition used an unflattened Append or
MergeAppend. As a result, ExecGetRangeTableRelation() reported an
error when called from CreatePartitionPruneState() to process the
partition's own PartitionPruneInfo, since it was treated as prunable
when it should not have been.
Reported-by: Alexander Lakhin <exclusion@gmail.com> (via sqlsmith)
Diagnosed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Discussion: https://postgr.es/m/74839af6-aadc-4f60-ae77-ae65f94bf607@gmail.com
When a standby replays an XLOG_PARAMETER_CHANGE record that lowers
wal_level below logical, we invalidate all logical slots in hot
standby mode. However, if this record was replayed while not in hot
standby mode, logical slots could remain valid even after promotion,
potentially causing an assertion failure during WAL record decoding.
To fix this issue, this commit adds a check for hot_standby status
when restoring a logical replication slot on standbys. This check
ensures that logical slots are invalidated when they become
incompatible due to insufficient wal_level during recovery.
Backpatch to v16 where logical decoding on standby was introduced.
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/CAD21AoABoFwGY_Rh2aeE6tEq3HkJxf0c6UeOXn4VV9v6BAQPSw%40mail.gmail.com
Backpatch-through: 16
Pages from the bitmap created by the TIDBitmap API can be exact or
lossy. The TIDBitmap API extracts the tuple offsets from exact pages
into an array for the convenience of the caller.
This was done in tbm_private|shared_iterate() right after advancing the
iterator. However, as long as tbm_private|shared_iterate() set a
reference to the PagetableEntry in the TBMIterateResult, the offset
extraction can be done later.
Waiting to extract the tuple offsets has a few benefits. For the shared
iterator case, it allows us to extract the offsets after dropping the
shared iterator state lock, reducing time spent holding a contended
lock.
Separating the iteration step and extracting the offsets later also
allows us to avoid extracting the offsets for prefetched blocks. Those
offsets were never used, so the overhead of extracting and storing them
was wasted.
The real motivation for this change, however, is that future commits
will make bitmap heap scan use the read stream API. This requires a
TBMIterateResult per issued block. By removing the array of tuple
offsets from the TBMIterateResult and only extracting the offsets when
they are used, we reduce the memory required for per buffer data
substantially.
Suggested-by: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKGLHbKP3jwJ6_%2BhnGi37Pw3BD5j2amjV3oSk7j-KyCnY7Q%40mail.gmail.com
Although they're exposed as int4 in pg_class, relpages and
relallvisible are really of type BlockNumber, that is uint32.
Correct type puns in relation_statistics_update() and remove
inappropriate range-checks. The type puns are only cosmetic
issues, but the range checks would cause failures with huge
relations.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Author: Corey Huinker <corey.huinker@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/614341.1740269035@sss.pgh.pa.us
Jacob reported that comments for LW_SHARED_MASK referenced a MAX_BACKENDS
limit of 2^23-1, but that MAX_BACKENDS is actually limited to 2^18-1. The
limit was lowered in 48354581a4, but the comment in lwlock.c wasn't updated.
Instead of just fixing the comment, it seems better to directly base the
lwlock defines on MAX_BACKENDS and add static assertions to ensure that there
is enough space. That way there's no comment that can go out of sync in the
future.
As part of that change I noticed that for some reason the high bit wasn't used
for flags, which seems somewhat odd. Redefine the flag values to start at the
highest bit.
Reported-by: Jacob Brazeal <jacob.brazeal@gmail.com>
Reviewed-by: Jacob Brazeal <jacob.brazeal@gmail.com>
Discussion: https://postgr.es/m/CA+COZaBO_s3LfALq=b+HcBHFSOEGiApVjrRacCe4VP9m7CJsNQ@mail.gmail.com
MAX_BACKENDS influences many things besides postmaster. I e.g. noticed that we
don't have static assertions ensuring BUF_REFCOUNT_MASK is big enough for
MAX_BACKENDS, adding them would require including postmaster.h in
buf_internals.h which doesn't seem right.
While at that, add MAX_BACKENDS_BITS, as that's useful in various places for
static assertions (to be added in subsequent commits).
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/wptizm4qt6yikgm2pt52xzyv6ycmqiutloyvypvmagn7xvqkce@d4xuv3mylpg4
The four following attributes are removed from pg_stat_wal:
* wal_write
* wal_sync
* wal_write_time
* wal_sync_time
a051e71e28 has added an equivalent of this information in pg_stat_io
with more granularity as this now spreads across the backend types, IO
context and IO objects. So, keeping the same information in pg_stat_wal
has little benefits.
Another benefit of this commit is the removal of PendingWalStats,
simplifying an upcoming patch to add per-backend WAL statistics, which
already support IO statistics and which have access to the write/sync
stats data of WAL.
The GUC track_wal_io_timing, that was used to enable or disable the
aggregation of the write and sync timings for WAL, is also removed.
pgstat_prepare_io_time() is simplified.
Bump catalog version.
Bump PGSTAT_FILE_FORMAT_ID, due to the update of PgStat_WalStats.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/Z7RkQ0EfYaqqjgz/@ip-10-97-1-34.eu-west-3.compute.internal
To implement AIO writes, the backend initiating writes needs to transfer the
lock ownership to the AIO subsystem, so the lock held during the write can be
released in another backend.
Other backends need to be able to "complete" an asynchronously started IO to
avoid deadlocks (consider e.g. one backend starting IO for a buffer and then
waiting for a heavyweight lock held by another relation followed by the
current holder of the heavyweight lock waiting for the IO to complete).
To that end, this commit adds LWLockDisown() and LWLockReleaseDisowned(). If
code uses LWLockDisown() it's the code's responsibility to ensure that the
lock is released in case of errors.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Discussion: https://postgr.es/m/1f6b50a7-38ef-4d87-8246-786d39f46ab9@iki.fi
Concurrently dropping either the granted role or the grantee
does not stop GRANT from completing, instead resulting in a
dangling role reference in pg_auth_members. That's relatively
harmless in the short run, but inconsistent catalog entries
are not a good thing.
This patch solves the problem by adding the granted and grantee
roles as explicit shared dependencies of the pg_auth_members entry.
That's a bit indirect, but it works because the pg_shdepend code
applies the necessary locking and rechecking.
Commit 6566133c5 previously established similar handling for
the grantor column of pg_auth_members; it's not clear why it
didn't cover the other two role OID columns.
A side-effect of this approach is that DROP OWNED BY will now drop
pg_auth_members entries that mention the target role as either the
granted or grantee role. That's clearly appropriate for the
grantee, since we'll drop its other privileges too. It doesn't
seem too far out of line for the granted role, since we're
presumably about to drop it and besides we're removing all reasons
why it'd matter to be a member of it. (One could argue that this
makes DropRole's code to auto-drop pg_auth_members entries
unnecessary, but I chose to leave it in place since perhaps some
people's workflows expect that to work without a DROP OWNED BY.)
Note to patch readers: CreateRole's first CommandCounterIncrement
call is now unconditional, because this change creates another
case in which it's needed, and it seemed to be more trouble than
it's worth to preserve that micro-optimization.
Arguably this is a bug fix, but the fact that it changes the
expected contents of pg_shdepend seems like not a great thing
to do in the stable branches, and perhaps we don't want the
change in DROP OWNED BY semantics there either. On the other
hand, I opted not to force a catversion bump in HEAD, because
the presence or absence of these entries doesn't matter for
most purposes.
Reported-by: Virender Singla <virender.cse@gmail.com>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Discussion: https://postgr.es/m/CAM6Zo8woa62ZFHtMKox6a4jb8qQ=w87R2L0K8347iE-juQL2EA@mail.gmail.com
When nloops > 1, we now display two digits after the decimal point,
rather than none. This is important because what we print is actually
planstate->instrument->ntuples / nloops, and sometimes what you want
to know is planstate->instrument->ntuples. You can estimate that by
multiplying the displayed row count by the displayed nloops value, but
the fact that the displayed value is rounded makes that inexact. It's
still inexact even if we show these two extra decimal places, but less
so. Perhaps we will agree on a way to further improve this output later,
but for now this seems better than doing nothing.
Author: Ibrar Ahmed <ibrar.ahmad@gmail.com>
Author: Ilia Evdokimov <ilya.evdokimov@tantorlabs.com>
Reviewed-by: David G. Johnston <david.g.johnston@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Greg Stark <stark@mit.edu>
Reviewed-by: Naeem Akhter <akhternaeem@gmail.com>
Reviewed-by: Hamid Akhtar <hamid.akhtar@percona.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andrei Lepikhov <a.lepikhov@postgrespro.ru>
Reviewed-by: Guillaume Lelarge <guillaume@lelarge.info>
Reviewed-by: Matheus Alcantara <matheusssilv97@gmail.com>
Reviewed-by: Alena Rybakina <a.rybakina@postgrespro.ru>
Discussion: http://postgr.es/m/603c8f070905281830g2e5419c4xad2946d149e21f9d%40mail.gmail.com
The signedness of the 'char' type in C is
implementation-dependent. For instance, 'signed char' is used by
default on x86 CPUs, while 'unsigned char' is used on aarch
CPUs. Previously, we accidentally let C implementation signedness
affect persistent data. This led to inconsistent results when
comparing char data across different platforms.
This commit introduces a new 'default_char_signedness' field in
ControlFileData to store the signedness of the 'char' type. While this
change does not encourage the use of 'char' without explicitly
specifying its signedness, this field can be used as a hint to ensure
consistent behavior for pre-v18 data files that store data sorted by
the 'char' type on disk (e.g., GIN and GiST indexes), especially in
cross-platform replication scenarios.
Newly created database clusters unconditionally set the default char
signedness to true. pg_upgrade (with an upcoming commit) changes this
flag for clusters if the source database cluster has
signedness=false. As a result, signedness=false setting will become
rare over time. If we had known about the problem during the last
development cycle that forced initdb (v8.3), we would have made all
clusters signed or all clusters unsigned. Making pg_upgrade the only
source of signedness=false will cause the population of database
clusters to converge toward that retrospective ideal.
Bump catalog version (for the catalog changes) and PG_CONTROL_VERSION
(for the additions in ControlFileData).
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/CB11ADBC-0C3F-4FE0-A678-666EE80CBB07%40amazon.com
This allows using text position search functions with nondeterministic
collations. These functions are
- position, strpos
- replace
- split_part
- string_to_array
- string_to_table
which all use common internal infrastructure.
There was previously no internal implementation of this, so it was met
with a not-supported error. This adds the internal implementation and
removes the error.
Unlike with deterministic collations, the search cannot use any
byte-by-byte optimized techniques but has to go substring by
substring. We also need to consider that the found match could have a
different length than the needle and that there could be substrings of
different length matching at a position. In most cases, we need to
find the longest such substring (greedy semantics), but this can be
configured by each caller.
Reviewed-by: Euler Taveira <euler@eulerto.com>
Discussion: https://www.postgresql.org/message-id/flat/582b2613-0900-48ca-8b0d-340c06f4d400@eisentraut.org
Previously, a WARNING was issued at the time of defining a subscription
with origin=NONE only when the publisher subscribed to the same table from
other publishers, indicating potential data origination from different
origins. However, the publisher can subscribe to the partition ancestors
or partition children of the table from other publishers, which could also
result in mixed-origin data inclusion. So, give a WARNING in those cases
as well.
Reported-by: Sergey Tatarintsev <s.tatarintsev@postgrespro.ru>
Author: Hou Zhijie <houzj.fnst@fujitsu.com>
Author: Shlok Kyal <shlok.kyal.oss@gmail.com>
Reviewed-by: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 16, where it was introduced
Discussion: https://postgr.es/m/5eda6a9c-63cf-404d-8a49-8dcb116a29f3@postgrespro.ru
The type argument wasn't actually really necessary. It was a remnant
of converting the API of the gist strategy translation from using
opclass to using opfamily+opcintype (commits c09e5a6a01,
622f678c10). For looking up the gist translation function, we used
the convention "amproclefttype = amprocrighttype = opclass's
opcintype" (see pg_amproc.h). But each operator family should only
have one translation function, and getting the right type for the
lookup is sometimes cumbersome and fragile, so this is all
unnecessarily complicated.
To simplify this, change the gist stategy support procedure to take
"any", "any" as argument. (This is arbitrary but seems intuitive.
The alternative of using InvalidOid as argument(s) upsets various DDL
commands, so it's not practical.) Then we don't need opcintype for
the lookup, and we can remove it from all the API layers introduced by
commit c09e5a6a01.
This also adds some more documentation about the correct signature of
the gist support function and adds more checks in gistvalidate().
This was previously underspecified. (It relied implicitly on
convention mentioned above.)
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
This commit implements OAUTHBEARER, RFC 7628, and OAuth 2.0 Device
Authorization Grants, RFC 8628. In order to use this there is a
new pg_hba auth method called oauth. When speaking to a OAuth-
enabled server, it looks a bit like this:
$ psql 'host=example.org oauth_issuer=... oauth_client_id=...'
Visit https://oauth.example.org/login and enter the code: FPQ2-M4BG
Device authorization is currently the only supported flow so the
OAuth issuer must support that in order for users to authenticate.
Third-party clients may however extend this and provide their own
flows. The built-in device authorization flow is currently not
supported on Windows.
In order for validation to happen server side a new framework for
plugging in OAuth validation modules is added. As validation is
implementation specific, with no default specified in the standard,
PostgreSQL does not ship with one built-in. Each pg_hba entry can
specify a specific validator or be left blank for the validator
installed as default.
This adds a requirement on libcurl for the client side support,
which is optional to build, but the server side has no additional
build requirements. In order to run the tests, Python is required
as this adds a https server written in Python. Tests are gated
behind PG_TEST_EXTRA as they open ports.
This patch has been a multi-year project with many contributors
involved with reviews and in-depth discussions: Michael Paquier,
Heikki Linnakangas, Zhihong Yu, Mahendrakar Srinivasarao, Andrey
Chudnovsky and Stephen Frost to name a few. While Jacob Champion
is the main author there have been some levels of hacking by others.
Daniel Gustafsson contributed the validation module and various bits
and pieces; Thomas Munro wrote the client side support for kqueue.
Author: Jacob Champion <jacob.champion@enterprisedb.com>
Co-authored-by: Daniel Gustafsson <daniel@yesql.se>
Co-authored-by: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Antonin Houska <ah@cybertec.at>
Reviewed-by: Kashif Zeeshan <kashi.zeeshan@gmail.com>
Discussion: https://postgr.es/m/d1b467a78e0e36ed85a09adf979d04cf124a9d4b.camel@vmware.com
Before executing a cached generic plan, AcquireExecutorLocks() in
plancache.c locks all relations in a plan's range table to ensure the
plan is safe for execution. However, this locks runtime-prunable
relations that will later be pruned during "initial" runtime pruning,
introducing unnecessary overhead.
This commit defers locking for such relations to executor startup and
ensures that if the CachedPlan is invalidated due to concurrent DDL
during this window, replanning is triggered. Deferring these locks
avoids unnecessary locking overhead for pruned partitions, resulting
in significant speedup, particularly when many partitions are pruned
during initial runtime pruning.
* Changes to locking when executing generic plans:
AcquireExecutorLocks() now locks only unprunable relations, that is,
those found in PlannedStmt.unprunableRelids (introduced in commit
cbc127917e), to avoid locking runtime-prunable partitions
unnecessarily. The remaining locks are taken by
ExecDoInitialPruning(), which acquires them only for partitions that
survive pruning.
This deferral does not affect the locks required for permission
checking in InitPlan(), which takes place before initial pruning.
ExecCheckPermissions() now includes an Assert to verify that all
relations undergoing permission checks, none of which can be in the
set of runtime-prunable relations, are properly locked.
* Plan invalidation handling:
Deferring locks introduces a window where prunable relations may be
altered by concurrent DDL, invalidating the plan. A new function,
ExecutorStartCachedPlan(), wraps ExecutorStart() to detect and handle
invalidation caused by deferred locking. If invalidation occurs,
ExecutorStartCachedPlan() updates CachedPlan using the new
UpdateCachedPlan() function and retries execution with the updated
plan. To ensure all code paths that may be affected by this handle
invalidation properly, all callers of ExecutorStart that may execute a
PlannedStmt from a CachedPlan have been updated to use
ExecutorStartCachedPlan() instead.
UpdateCachedPlan() replaces stale plans in CachedPlan.stmt_list. A new
CachedPlan.stmt_context, created as a child of CachedPlan.context,
allows freeing old PlannedStmts while preserving the CachedPlan
structure and its statement list. This ensures that loops over
statements in upstream callers of ExecutorStartCachedPlan() remain
intact.
ExecutorStart() and ExecutorStart_hook implementations now return a
boolean value indicating whether plan initialization succeeded with a
valid PlanState tree in QueryDesc.planstate, or false otherwise, in
which case QueryDesc.planstate is NULL. Hook implementations are
required to call standard_ExecutorStart() at the beginning, and if it
returns false, they should do the same without proceeding.
* Testing:
To verify these changes, the delay_execution module tests scenarios
where cached plans become invalid due to changes in prunable relations
after deferred locks.
* Note to extension authors:
ExecutorStart_hook implementations must verify plan validity after
calling standard_ExecutorStart(), as explained earlier. For example:
if (prev_ExecutorStart)
plan_valid = prev_ExecutorStart(queryDesc, eflags);
else
plan_valid = standard_ExecutorStart(queryDesc, eflags);
if (!plan_valid)
return false;
<extension-code>
return true;
Extensions accessing child relations, especially prunable partitions,
via ExecGetRangeTableRelation() must now ensure their RT indexes are
present in es_unpruned_relids (introduced in commit cbc127917e), or
they will encounter an error. This is a strict requirement after this
change, as only relations in that set are locked.
The idea of deferring some locks to executor startup, allowing locks
for prunable partitions to be skipped, was first proposed by Tom Lane.
Reviewed-by: Robert Haas <robertmhaas@gmail.com> (earlier versions)
Reviewed-by: David Rowley <dgrowleyml@gmail.com> (earlier versions)
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> (earlier versions)
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Discussion: https://postgr.es/m/CA+HiwqFGkMSge6TgC9KQzde0ohpAycLQuV7ooitEEpbKB0O_mg@mail.gmail.com
If the requested recovery timeline is not reachable, the logged
checkpoint and timeline should to be the values read from the
backup_label when it is defined. The message generated used the values
from the control file in this case, which is fine when recovering from
the control file without a backup_label, but not if there is a
backup_label.
Issue introduced in ee994272ca. v15 has introduced xlogrecovery.c and
more simplifications in this area (4a92a1c3d1, a27048cbcb), making
this change a bit simpler to think about, so backpatch only down to this
version.
Author: David Steele <david@pgbackrest.org>
Reviewed-by: Andrey M. Borodin <x4mmm@yandex-team.ru>
Reviewed-by: Benoit Lobréau <benoit.lobreau@dalibo.com>
Discussion: https://postgr.es/m/c3d617d4-1696-4aa7-8a4d-5a7d19cc5618@pgbackrest.org
Backpatch-through: 15
Since commit 29cf61ade3, table_block_relation_estimate_size() considers
fillfactor when estimating number of rows in a relation before the first
ANALYZE. The formula however did not consider tuples may be larger than
available space determined by fillfactor, ending with density 0. This
ultimately means the relation was estimated to contain a single row.
The executor however places at least one tuple per page, even with very
low fillfactor values, so the density should be at least 1. Fixed by
clamping the density estimate using clamp_row_est().
Reported by Heikki Linnakangas. Fix by me, with regression test inspired
by example provided by Heikki.
Backpatch to 17, where the issue was introduced.
Reported-by: Heikki Linnakangas
Backpatch-through: 17
Discussion: https://postgr.es/m/2bf9d973-7789-4937-a7ca-0af9fb49c71e@iki.fi
These functions should be called at most once per ResultRelInfo;
it's wasteful to do otherwise, and certainly the pattern of
opening twice and then closing twice is a bad idea. Moreover,
aminsertcleanup functions might not be prepared to be called twice,
as the just-hardened code in BRIN demonstrates.
This amounts to an API change, since such coding patterns were
safe even if wasteful before v17. Hence, apply to HEAD only.
(Extension code violating this new rule faces some risk in v17,
but we just fixed brininsertcleanup and there are probably few
other aminsertcleanup functions as yet. So the odds of breaking
usable code seem higher than the odds of doing something useful
with a back-patch.)
Bug: #18815
Reported-by: Sergey Belyashov <sergey.belyashov@gmail.com>
Discussion: https://postgr.es/m/18815-2a0407cc7f40b327@postgresql.org
Logical replication crashes if the subscriber's partitioned table
has a BRIN index. There are two independently blamable causes,
and this patch fixes both:
1. brininsertcleanup fails if called twice for the same IndexInfo,
because it half-destroys its BrinInsertState but leaves it still
linked from ii_AmCache. brininsert would also fail in that state,
so it's pretty hard to see any advantage to this coding. Fully
remove the BrinInsertState, instead, so that a new brininsert
call would create a new cache.
2. A logical replication subscriber sometimes does ExecOpenIndices
twice on the same ResultRelInfo, followed by doing ExecCloseIndices
twice; the second call reaches the brininsertcleanup bug. Quite
aside from tickling unexpected cases in aminsertcleanup methods,
this seems very wasteful, because the IndexInfos built in the
first ExecOpenIndices call are just lost during the second call,
and have to be rebuilt at possibly-nontrivial cost. We should
establish a coding rule that you don't do that.
The problematic coding is that when the target table is partitioned,
apply_handle_tuple_routing calls ExecFindPartition which does
ExecOpenIndices (and expects that ExecCleanupTupleRouting will
close the indexes again). Using the ResultRelInfo made by
ExecFindPartition, it calls apply_handle_delete_internal or
apply_handle_insert_internal, both of which think they need to do
ExecOpenIndices/ExecCloseIndices for themselves. They do in the main
non-partitioned code paths, but not here. The simplest fix is to pull
their ExecOpenIndices/ExecCloseIndices calls out and put them in the
call sites for the non-partitioned cases. (We could have refactored
apply_handle_update_internal similarly, but I did not do so today
because there's no bug there: the partitioned code path doesn't
call it.)
Also, remove the always-duplicative open/close calls within
apply_handle_tuple_routing itself.
Since brininsertcleanup and indeed the whole aminsertcleanup mechanism
are new in v17, there's no observable bug in older branches. A case
could be made for trying to avoid these duplicative open/close calls
in the older branches, but for now it seems not worth the trouble and
risk of new bugs.
Bug: #18815
Reported-by: Sergey Belyashov <sergey.belyashov@gmail.com>
Discussion: https://postgr.es/m/18815-2a0407cc7f40b327@postgresql.org
Backpatch-through: 17
Until now ExecChooseHashTableSize() considered only the size of the
in-memory hash table, and ignored the memory needed for the batch files.
Which can be a significant amount, because each batch needs two BufFiles
(each with a BLCKSZ buffer). The same issue applies to increasing the
number of batches during execution.
It's also possible to trigger a "batch explosion", e.g. due to duplicate
values or skew. We've seen reports of joins with hundreds of thousands
(or even millions) of batches, consuming gigabytes of memory, triggering
OOM errors. These cases may be fairly rare, but it's clearly possible to
hit them.
These issues can't be prevented during planning. Even if we improve
that, it does not help with execution-time batch explosion. We can
however reduce the impact and use as little memory as possible.
This patch improves the behavior by adjusting how the memory is divided
between the hash table and batch files. It may be better to use fewer
batch files, even if it means the hash table will exceed the limit.
The capacity of the hash node may be increased either by doubling he
number of batches, or doubling the size of the in-memory hash table. The
outcome is the same, but the memory usage may be very different. For low
nbatch values it's better to add batches, for high nbatch values it's
better to allow a larger hash table.
The patch considers both options, both during the initial sizing and
then during execution, to minimize how much the limit gets exceeded.
It might seem this patch is relaxing the memory limit - allowing it to
be exceeded. But that's not really the case. It has always been like
that, except the memory used by batches was ignored.
Allowing the hash table to grow may also prevent the batch explosion.
If there's a large batch that can't be split (due to hash collisions or
duplicate values), at some point the memory limit will increase enough
for the batch to fit into the hash table.
This patch was in the works for a long time. The early versions were
posted in 2019, and revived every year or two when we happened to get
the next report of OOM due to a hashjoin batch explosion. Each of those
patch versions were reviewed by a couple people. I'm mentioning only
Melanie Plageman and Robert Haas, because they reviewed the last
version, and the older patches are very different.
Reviewed-by: Melanie Plageman, Robert Haas
Discussion: https://postgr.es/m/7bed6c08-72a0-4ab9-a79c-e01fcdd0940f@vondra.me
Discussion: https://postgr.es/m/20190504003414.bulcbnge3rhwhcsh%40development
Discussion: https://postgr.es/m/20190428141901.5dsbge2ka3rxmpk6%40development
Replace the use of Constraint with a new ATAlterConstraint struct, which
allows us to pass additional information. No functionality is added by
this commit. This is necessary for future work that allows altering
constraints in other ways.
I (Álvaro) took the liberty of restructuring the code for ALTER
CONSTRAINT beyond what Amul did. The original coding before Amul's
patch was unnecessarily baroque, and this change makes things simpler
by removing one level of subroutine. Also, partly remove the assumption
that only partitioned tables are relevant (by passing sensible 'recurse'
arguments) and no longer ignore whether ONLY was specified. I say
'partly' because the current coding only walks down via the 'conparentid'
relationship, which is only used for partitioned tables; but future
patches could handle ONLY or not for other types of constraint changes
for legacy inheritance trees too.
Author: Amul Sul <sulamul@gmail.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/CAAJ_b94bfgPV-8Mw_HwSBeheVwaK9=5s+7+KbBj_NpwXQFgDGg@mail.gmail.com
This commit follows the idea of the 4767bc8ff2. If sub-query has only one
GROUP BY column, we can consider its output variable as being unique. We can
employ this fact in the statistics to make more precise estimations in the
upper query block.
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
This test uses an injection point to bypass the time overhead caused by
the idle_replication_slot_timeout GUC, which has a minimum value of one
minute.
Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Author: Nisha Moond <nisha.moond412@gmail.com>
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/CALj2ACW4aUe-_uFQOjdWCEN-xXoLGhmvRFnL8SNw_TZ5nJe+aw@mail.gmail.com
LIKE enables the creation of foreign tables based on the column
definitions, constraints and objects of the defined source relation(s).
This feature mirrors the behavior of CREATE TABLE LIKE, but ignores
the INCLUDING sub-options that do not make sense for foreign tables:
INDEXES, COMPRESSION, IDENTITY and STORAGE. The supported sub-options
are COMMENTS, CONSTRAINTS, DEFAULTS, GENERATED and STATISTICS, mapping
with the clauses already supported by the command.
Note that the restriction with LIKE in CREATE FOREIGN TABLE was added in
a0c6dfeecf.
Author: Zhang Mingli
Reviewed-by: Álvaro Herrera, Sami Imseih, Michael Paquier
Discussion: https://postgr.es/m/42d3f855-2275-4361-a42a-826172ca2dc4@Spark
This commit introduces idle_replication_slot_timeout GUC that allows
inactive slots to be invalidated at the time of checkpoint. Because
checkpoints happen checkpoint_timeout intervals, there can be some lag
between when the idle_replication_slot_timeout was exceeded and when the
slot invalidation is triggered at the next checkpoint. To avoid such lags,
users can force a checkpoint to promptly invalidate inactive slots.
Note that the idle timeout invalidation mechanism is not applicable for
slots that do not reserve WAL or for slots on the standby server that are
synced from the primary server (i.e., standby slots having 'synced' field
'true'). Synced slots are always considered to be inactive because they
don't perform logical decoding to produce changes.
The slots can become inactive for a long period if a subscriber is down
due to a system error or inaccessible because of network issues. If such a
situation persists, it might be more practical to recreate the subscriber
rather than attempt to recover the node and wait for it to catch up which
could be time-consuming.
Then, external tools could create replication slots (e.g., for migrations
or upgrades) that may fail to remove them if an error occurs, leaving
behind unused slots that take up space and resources. Manually cleaning
them up can be tedious and error-prone, and without intervention, these
lingering slots can cause unnecessary WAL retention and system bloat.
As the duration of idle_replication_slot_timeout is in minutes, any test
using that would be time-consuming. We are planning to commit a follow up
patch for tests by using the injection point framework.
Author: Nisha Moond <nisha.moond412@gmail.com>
Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Hou Zhijie <houzj.fnst@fujitsu.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/CALj2ACW4aUe-_uFQOjdWCEN-xXoLGhmvRFnL8SNw_TZ5nJe+aw@mail.gmail.com
Discussion: https://postgr.es/m/OS0PR01MB5716C131A7D80DAE8CB9E88794FC2@OS0PR01MB5716.jpnprd01.prod.outlook.com
It's been some time since we did this, partly because the upstream
snowball project hasn't formally tagged a new release since 2021.
The main motivation for doing it now is to absorb a bug fix
(their commit e322673a841d9abd69994ae8cd20e191090b6ef4), which
prevents a null pointer dereference crash if SN_create_env() gets
a malloc failure at just the wrong point. We'll patch the back
branches with only that change, but we might as well do the full
sync dance on HEAD.
Aside from a bunch of mostly-minor tweaks to existing stemmers, this
update adds a new stemmer for Estonian. It also removes the existing
stemmer for Romanian using ISO-8859-2 encoding. Upstream apparently
concluded that ISO-8859-2 doesn't provide an adequate representation
of some Romanian characters, and the UTF-8 implementation should be
used instead.
While at it, update the README's instructions for doing a sync,
which have not been adjusted during the addition of meson tooling.
Thanks to Maksim Korotkov for discovering the null-pointer
bug and submitting the fix to upstream snowball.
Reported-by: Maksim Korotkov <m.korotkov@postgrespro.ru>
Discussion: https://postgr.es/m/1d1a46-67ab1000-21-80c451@83151435
When considering a local buffer, the GetBufferDescriptor() call in
BufferGetLSNAtomic() would be retrieving a shared buffer with a bad
buffer ID. Since the code checks whether the buffer is shared before
using the retrieved BufferDesc, this issue did not lead to any
malfunction. Nonetheless this seems like trouble waiting to happen,
so fix it by ensuring that GetBufferDescriptor() is only called when
we know the buffer is shared.
Author: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Xuneng Zhou <xunengzhou@gmail.com>
Reviewed-by: Richard Guo <guofenglinux@gmail.com>
Discussion: https://postgr.es/m/CAHewXNku-o46-9cmUgyv6LkSZ25doDrWq32p=oz9kfD8ovVJMg@mail.gmail.com
Backpatch-through: 13
In try_partitionwise_join, we try to break down the join between two
partitioned relations into joins between matching partitions. To
achieve this, we iterate through each pair of partitions from the two
joining relations and create child join relations for them. To reduce
memory accumulation during each iteration, one step we take is freeing
the SpecialJoinInfos created for the child joins.
A child join's SpecialJoinInfo is a copy of the parent join's
SpecialJoinInfo, with some members being translated copies of their
counterparts in the parent. However, when freeing the bitmapset
members in a child join's SpecialJoinInfo, we failed to check whether
they were translated copies. As a result, we inadvertently freed the
members that were still in use by the parent SpecialJoinInfo, leading
to crashes when those freed members were accessed.
To fix, check if each member of the child join's SpecialJoinInfo is a
translated copy and free it only if that's the case. This requires
passing the parent join's SpecialJoinInfo as a parameter to
free_child_join_sjinfo.
Back-patch to v17 where this bug crept in.
Bug: #18806
Reported-by: 孟令彬 <m_lingbin@126.com>
Diagnosed-by: Tender Wang <tndrwang@gmail.com>
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Amit Langote <amitlangote09@gmail.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: https://postgr.es/m/18806-d70b0c9fdf63dcbf@postgresql.org
Backpatch-through: 17
This commit improves the description of a couple of GUCs, to be more
consistent with the style of their surroundings:
* array_nulls
* enable_self_join_elimination
* optimize_bounded_sort
* row_security
* synchronize_seqscans
Author: Kyotaro Horiguchi
Discussion: https://postgr.es/m/20250218.103240.1422205966404509831.horikyota.ntt@gmail.com
Move lazy_scan_heap()'s per_buffer_data variable into a tighter scope.
In lazy_scan_heap()'s phase I heap vacuuming, the read stream API
returns a pointer to the next block number to vacuum. As long as
read_stream_next_buffer() returns a valid buffer, per_buffer_data should
always be valid.
Move per_buffer_data into a tighter scope and make sure it is reset to
NULL on each iteration so that we get a core dump instead of bogus data
from a previous block if something goes wrong in the read stream API.
Suggested-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/626104.1739729538%40sss.pgh.pa.us
Builds configured with Valgrind but without assertions would fail due to
a typo in the recent change. This should be included when back-patching
2a8a0067 into v17.
The translator comments detailing what a %s inclusion refers to were
accidentally including too many address types. In practice this is
not a problem since it's not a translated string, but to minimize any
risk of confusion let's fix them anwyays. Even though this exists in
backbranches there is little use for backpatch as the translation work
has already happened there, so let's avoid the churn.
Author: Japin Li <japinli@hotmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/ME0P300MB04458DE627480614ABE639D2B6FB2@ME0P300MB0445.AUSP300.PROD.OUTLOOK.COM
The Self-Join Elimination (SJE) feature removes an inner join of a plain
table to itself in the query tree if it is proven that the join can be
replaced with a scan without impacting the query result. Self-join and
inner relation get replaced with the outer in query, equivalence classes,
and planner info structures. Also, the inner restrictlist moves to the
outer one with the removal of duplicated clauses. Thus, this optimization
reduces the length of the range table list (this especially makes sense for
partitioned relations), reduces the number of restriction clauses and,
in turn, selectivity estimations, and potentially improves total planner
prediction for the query.
This feature is dedicated to avoiding redundancy, which can appear after
pull-up transformations or the creation of an EquivalenceClass-derived clause
like the below.
SELECT * FROM t1 WHERE x IN (SELECT t3.x FROM t1 t3);
SELECT * FROM t1 WHERE EXISTS (SELECT t3.x FROM t1 t3 WHERE t3.x = t1.x);
SELECT * FROM t1,t2, t1 t3 WHERE t1.x = t2.x AND t2.x = t3.x;
In the future, we could also reduce redundancy caused by subquery pull-up
after unnecessary outer join removal in cases like the one below.
SELECT * FROM t1 WHERE x IN
(SELECT t3.x FROM t1 t3 LEFT JOIN t2 ON t2.x = t1.x);
Also, it can drastically help to join partitioned tables, removing entries
even before their expansion.
The SJE proof is based on innerrel_is_unique() machinery.
We can remove a self-join when for each outer row:
1. At most, one inner row matches the join clause;
2. Each matched inner row must be (physically) the same as the outer one;
3. Inner and outer rows have the same row mark.
In this patch, we use the next approach to identify a self-join:
1. Collect all merge-joinable join quals which look like a.x = b.x;
2. Add to the list above the baseretrictinfo of the inner table;
3. Check innerrel_is_unique() for the qual list. If it returns false, skip
this pair of joining tables;
4. Check uniqueness, proved by the baserestrictinfo clauses. To prove the
possibility of self-join elimination, the inner and outer clauses must
match exactly.
The relation replacement procedure is not trivial and is partly combined
with the one used to remove useless left joins. Tests covering this feature
were added to join.sql. Some of the existing regression tests changed due
to self-join removal logic.
Discussion: https://postgr.es/m/flat/64486b0b-0404-e39e-322d-0801154901f3%40postgrespro.ru
Author: Andrey Lepikhov <a.lepikhov@postgrespro.ru>
Author: Alexander Kuzmenkov <a.kuzmenkov@postgrespro.ru>
Co-authored-by: Alexander Korotkov <aekorotkov@gmail.com>
Co-authored-by: Alena Rybakina <lena.ribackina@yandex.ru>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Simon Riggs <simon@2ndquadrant.com>
Reviewed-by: Jonathan S. Katz <jkatz@postgresql.org>
Reviewed-by: David Rowley <david.rowley@2ndquadrant.com>
Reviewed-by: Thomas Munro <thomas.munro@enterprisedb.com>
Reviewed-by: Konstantin Knizhnik <k.knizhnik@postgrespro.ru>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Hywel Carver <hywel@skillerwhale.com>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: Ronan Dunklau <ronan.dunklau@aiven.io>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Reviewed-by: Zhihong Yu <zyu@yugabyte.com>
Reviewed-by: Greg Stark <stark@mit.edu>
Reviewed-by: Jaime Casanova <jcasanov@systemguards.com.ec>
Reviewed-by: Michał Kłeczek <michal@kleczek.org>
Reviewed-by: Alena Rybakina <lena.ribackina@yandex.ru>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
ExecInitModifyTable() forgot to trim MERGE-related lists to exclude
entries for result relations pruned during initial pruning, so fix
that.
While at it, make the function's use of the pruned resultRelations
list, rather than ModifyTable.resultRelations, more consistent.
Reported-by: Alexander Lakhin <exclusion@gmail.com> (via sqlsmith)
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Discussion: https://postgr.es/m/e72c94d9-e5f9-4753-9bc1-69d72bd54b8a@gmail.com
This commit adds the information about the number of times WAL buffers
have been full to the logs generated by VACUUM/ANALYZE (VERBOSE) and in
the logs generated by autovacuum, complementing the existing information
stored by WalUsage.
This is the last part of the backend code where the value of
wal_buffers_full can be reported, similarly to all the other fields of
WalUsage. 320545bfcf and ce5bcc4a9f have done the same for EXPLAIN
and pgss.
Author: Bertrand Drouvot
Reviewed-by: Ilia Evdokimov
Discussion: https://postgr.es/m/Z6SOha5YFFgvpwQY@ip-10-97-1-34.eu-west-3.compute.internal
wal_buffers_full has been introduced in pg_stat_wal in 8d9a935965, as
some information providing metrics for the tuning of the GUC
wal_buffers. WalUsage has been introduced before that in df3b181499.
Moving this field is proving to be beneficial for several reasons:
- This information can now be made available in more layers, providing
more granularity than just pg_stat_wal, on a per-query basis: EXPLAIN,
pgss and VACUUM/ANALYZE logs.
- A patch is under discussion to provide statistics for WAL at backend
level, and this move simplifies a bit the handling of pending
statistics. The remaining data in PgStat_PendingWalStats now relates to
write/sync counters and times, with equivalents present in pg_stat_io,
that backend statistics are able to already track. So this should cut
all the dependencies between PgStat_PendingWalStats and WAL stats at
backend level.
As of this change, wal_buffers_full only shows in pg_stat_wal.
Author: Bertrand Drouvot
Reviewed-by: Ilia Evdokimov
Discussion: https://postgr.es/m/Z6SOha5YFFgvpwQY@ip-10-97-1-34.eu-west-3.compute.internal
Allow multiple backends to initialize WAL buffers concurrently. This way
`MemSet((char *) NewPage, 0, XLOG_BLCKSZ);` can run in parallel without
taking a single LWLock in exclusive mode.
The new algorithm works as follows:
* reserve a page for initialization using XLogCtl->InitializeReserved,
* ensure the page is written out,
* once the page is initialized, try to advance XLogCtl->InitializedUpTo and
signal to waiters using XLogCtl->InitializedUpToCondVar condition
variable,
* repeat previous steps until we reserve initialization up to the target
WAL position,
* wait until concurrent initialization finishes using a
XLogCtl->InitializedUpToCondVar.
Now, multiple backends can, in parallel, concurrently reserve pages,
initialize them, and advance XLogCtl->InitializedUpTo to point to the latest
initialized page.
Author: Yura Sokolov <y.sokolov@postgrespro.ru>
Co-authored-by: Alexander Korotkov <aekorotkov@gmail.com>
Reviewed-by: Pavel Borisov <pashkin.elfe@gmail.com>
In set_append_rel_size(), we currently set rel->tuples to rel->rows
for an appendrel. Generally, rel->tuples is the raw number of tuples
in the relation and rel->rows is the estimated number of tuples after
the relation's restriction clauses have been applied. Although an
appendrel itself doesn't directly enforce any quals today, its child
relations may. Therefore, setting rel->tuples equal to rel->rows for
an appendrel isn't always appropriate.
Doing so can lead to issues in cost estimates in some cases. For
instance, when estimating the number of distinct values from an
appendrel, we would not be able to adjust the estimate based on the
restriction selectivity.
This patch addresses this by setting an appendrel's tuples to the
total number of tuples accumulated from each live child, which better
aligns with reality.
This is arguably a bug, but nobody has complained about that until
now, so no back-patch.
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Alena Rybakina <a.rybakina@postgrespro.ru>
Discussion: https://postgr.es/m/CAMbWs4_TG_+kVn6fjG-5GYzzukrNK57=g9eUo4gsrUG26OFawg@mail.gmail.com
By calling wipe_mem() on per-buffer data memory that has been released,
we are also telling Valgrind that the memory is "noaccess". We need to
set it to "undefined" before giving it to the registered callback to
fill in, when a slot is reused.
As discovered by build farm animal skink when the VACUUM streamification
patches landed (the first users of per-buffer data).
Pushing to master only for now, to clear the error on skink. It's also
possible that external code might discover the per-buffer data feature
in v17, and reasonable to expect Valgrind not to produce spurious
memcheck reports, but the back-patch is deferred until after the
imminent minor release is out of the way.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Tested-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKG%2Bg6aXpi2FEHqeLOzE%2BxYw%3DOV%2B-N5jhOEnnV%2BF0USM9xA%40mail.gmail.com
Commit bb8dff9995 added this information to the
pg_stat_progress_vacuum and pg_stat_progress_analyze system views.
This commit adds the same information to the output of VACUUM and
ANALYZE with the VERBOSE option and to the autovacuum logs.
Suggested-by: Masahiro Ikeda <ikedamsh@oss.nttdata.com>
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/ZmaXmWDL829fzAVX%40ip-10-97-1-34.eu-west-3.compute.internal
Make vacuum's third phase (its second pass over the heap), which reaps
dead items collected in the first phase and marks them as reusable, use
the read stream API. This commit adds a new read stream callback,
vacuum_reap_lp_read_stream_next(), that looks ahead in the TidStore and
returns the next block number to read for vacuum.
Author: Melanie Plageman <melanieplageman@gmail.com>
Co-authored-by: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKGKN3oy0bN_3yv8hd78a4%2BM1tJC9z7mD8%2Bf%2ByA%2BGeoFUwQ%40mail.gmail.com
Make vacuum's first phase, which prunes and freezes tuples and records
dead TIDs, use the read stream API by by converting
heap_vac_scan_next_block() to a read stream callback.
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_aLwANZpxHc0tC-6OT0OQT4TftDGkKAO5yigMUOv_Tcsw%40mail.gmail.com
The read stream API only allows one piece of extra per block state to be
passed back to the API user (per_buffer_data). lazy_scan_heap() needs
two pieces of per-buffer data: whether or not the block was all-visible
in the visibility map and whether or not it was eagerly scanned.
Convert these two pieces of information to flags so that they can be
populated by heap_vac_scan_next_block() and returned to
lazy_scan_heap(). A future commit will turn heap_vac_scan_next_block()
into the read stream callback for heap phase I vacuuming.
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_bmx33jTqATP5GKNFYwAg02a9dDtk4U_ciEjgBHZSVkOQ%40mail.gmail.com
Many GUCs accept special values like -1 or an empty string to
disable the feature, use a system default, etc. While the
documentation consistently lists these special values, the GUC
descriptions do not. Many such descriptions fail to mention the
special values, and those that do vary in phrasing and placement.
This commit aims to bring some consistency to this area by applying
the following rules:
* Special values should be listed at the end of the long
description.
* Descriptions should use numerals (e.g., "0") instead of words
(e.g., "zero").
* Special value mentions should be concise and direct (e.g., "0
disables the timeout.", "An empty string means use the operating
system setting.").
* Multiple special values should be listed in ascending order.
Of course, there are exceptions, such as
max_pred_locks_per_relation and search_path, whose special values
are too complex to include. And there are cases like
listen_addresses, where the meaning of an empty string is arguably
too obvious to include. In those cases, I've refrained from adding
special value information to the GUC description.
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: "David G. Johnston" <david.g.johnston@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/Z6aIy4aywxUZHAo6%40nathan
Commit 27cc7cd2bc accidentally placed the assertion ensuring
that the pointer isn't NULL after it had already been accessed.
Fix by moving the pointer dereferencing to after the assertion.
Backpatch to all supported branches.
Author: Dmitry Koval <d.koval@postgrespro.ru>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/1618848d-cdc7-414b-9c03-08cf4bef4408@postgrespro.ru
Backpatch-through: 13
When an UPDATE trigger referencing a new table and a DELETE trigger
referencing an old table are both present, MakeTransitionCaptureState()
returns an inconsistent result for UPDATE commands in its set of flags
and tuplestores holding the TransitionCaptureState for transition
tables.
As proved by the test added here, this issue causes a crash in v14 and
earlier versions (down to 11, actually, older versions do not support
triggers on partitioned tables) during cross-partition updates on a
partitioned table. v15 and newer versions are safe thanks to
7103ebb7aa.
This commit fixes the function so that it returns a consistent state
by using portions of the changes made in commit 7103ebb7aa for v13 and
v14. v15 and newer versions are slightly tweaked to match with the
older versions, mainly for consistency across branches.
Author: Kyotaro Horiguchi
Discussion: https://postgr.es/m/20250207.150238.968446820828052276.horikyota.ntt@gmail.com
Backpatch-through: 13
RBTXN_PREPARE flag and rbtxn_prepared macro could be misinterpreted as
either indicating the transaction type (e.g. a prepared transaction or
a normal transaction) or its currentstate (e.g. skipped or its prepare
message is sent), especially after commit 072ee847ad introduced the
RBTXN_SENT_PREPARE flag and the rbtxn_sent_prepare macro.
The RBTXN_PREPARE flag (and its corresponding macro) have been renamed
to RBTXN_IS_PREPARE to explicitly indicate the transaction
type. Therefore, this commit also adds the RBTXN_IS_PREPARE flag to
the transaction that is a prepared transaction and has been skipped,
which previously had only the RBTXN_SKIPPED_PREPARE flag.
Reviewed-by: Amit Kapila, Peter Smith
Discussion: https://postgr.es/m/CAA4eK1KgNmBsG%3D155E7QQ6TX9RoWnM4z5Z20SvsbwxSe_QXYsg%40mail.gmail.com
Previously, transaction aborts were detected concurrently only during
system catalog scans while replaying a transaction in streaming mode.
This commit adds an additional CLOG lookup to check the transaction
status, allowing the logical decoding to skip changes also when it
doesn't touch system catalogs, if the transaction is already
aborted. This optimization enhances logical decoding performance,
especially for large transactions that have already been rolled back,
as it avoids unnecessary disk or network I/O.
To avoid potential slowdowns caused by frequent CLOG lookups for small
transactions (most of which commit), the CLOG lookup is performed only
for large transactions before eviction. The performance benchmark
results showed there is not noticeable performance regression due to
CLOG lookups.
Reviewed-by: Amit Kapila, Peter Smith, Vignesh C, Ajin Cherian
Reviewed-by: Dilip Kumar, Andres Freund
Discussion: https://postgr.es/m/CAD21AoDht9Pz_DFv_R2LqBTBbO4eGrpa9Vojmt5z5sEx3XwD7A@mail.gmail.com
Currently, the save_nestlevel variable in fmgr_security_definer()
is marked volatile. While this may have been necessary when it was
used in a PG_CATCH section (as explained in the comment for PG_TRY
in elog.h), it appears to have been unnecessary since commit
82a47982f3, which removed its use in a PG_CATCH section.
Author: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/Z6xbAgXKY2L-3d5Q%40jrouhaud
Remove some (char *) casts related to uses of the pg_checksum_page()
function. These casts are useless, because everything involved
already has the right type. Moreover, these casts actually silently
discarded a const qualifier. The declaration of a higher-level
function needs to be adjusted to fix that.
Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: https://www.postgresql.org/message-id/flat/fd1fcedb-3492-4fc8-9e3e-74b97f2db6c7%40eisentraut.org
Remove (char *) casts around memory functions such as memcmp(),
memcpy(), or memset() where the cast is useless. Since these
functions don't take char * arguments anyway, these casts are at best
complicated casts to (void *), about which see commit 7f798aca1d.
Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: https://www.postgresql.org/message-id/flat/fd1fcedb-3492-4fc8-9e3e-74b97f2db6c7%40eisentraut.org
Remove (char *) casts around string functions where the arguments or
result already have the right type and the cast is useless (or worse,
potentially casts away a qualifier, but this doesn't appear to be the
case here).
Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: https://www.postgresql.org/message-id/flat/fd1fcedb-3492-4fc8-9e3e-74b97f2db6c7%40eisentraut.org
This commit adds the amount of time spent sleeping due to
cost-based delay to the pg_stat_progress_vacuum and
pg_stat_progress_analyze system views. A new configuration
parameter named track_cost_delay_timing, which is off by default,
controls whether this information is gathered. For vacuum, the
reported value includes the sleep time of any associated parallel
workers. However, parallel workers only report their sleep time
once per second to avoid overloading the leader process.
Bumps catversion.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Co-authored-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Masahiro Ikeda <ikedamsh@oss.nttdata.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: Sergei Kornilov <sk@zsrv.org>
Discussion: https://postgr.es/m/ZmaXmWDL829fzAVX%40ip-10-97-1-34.eu-west-3.compute.internal
This function is used in both vacuum and analyze code paths, and a
follow-up commit will require distinguishing between the two. This
commit forces callers to specify whether they are in a vacuum or
analyze path, but it does not use that information for anything
yet.
Author: Nathan Bossart <nathandbossart@gmail.com>
Co-authored-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/ZmaXmWDL829fzAVX%40ip-10-97-1-34.eu-west-3.compute.internal
Aggressive vacuums must scan every unfrozen tuple in order to advance
the relfrozenxid/relminmxid. Because data is often vacuumed before it is
old enough to require freezing, relations may build up a large backlog
of pages that are set all-visible but not all-frozen in the visibility
map. When an aggressive vacuum is triggered, all of these pages must be
scanned. These pages have often been evicted from shared buffers and
even from the kernel buffer cache. Thus, aggressive vacuums often incur
large amounts of extra I/O at the expense of foreground workloads.
To amortize the cost of aggressive vacuums, eagerly scan some
all-visible but not all-frozen pages during normal vacuums.
All-visible pages that are eagerly scanned and set all-frozen in the
visibility map are counted as successful eager freezes and those not
frozen are counted as failed eager freezes.
If too many eager scans fail in a row, eager scanning is temporarily
suspended until a later portion of the relation. The number of failures
tolerated is configurable globally and per table.
To effectively amortize aggressive vacuums, we cap the number of
successes as well. Capping eager freeze successes also limits the amount
of potentially wasted work if these pages are modified again before the
next aggressive vacuum. Once we reach the maximum number of blocks
successfully eager frozen, eager scanning is disabled for the remainder
of the vacuum of the relation.
Original design idea from Robert Haas, with enhancements from
Andres Freund, Tomas Vondra, and me
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Robert Treat <rob@xzilla.net>
Reviewed-by: Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/flat/CAAKRu_ZF_KCzZuOrPrOqjGVe8iRVWEAJSpzMgRQs%3D5-v84cXUg%40mail.gmail.com
"I/O" seems more descriptive than "Asynchronous Behavior", given that some of
the GUCs in the section don't relate to anything asynchronous.
Most other abbreviations in the config sections are un-abbreviated, but
"Input/Output" seems less likely to be helpful than just IO or I/O.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/x3tlw2jk5gm3r3mv47hwrshffyw7halpczkfbk3peksxds7bvc@lguk43z3bsyq
Commit 1dc5ebc90 allowed PL/pgSQL to perform in-place updates
of expanded-object variables that are being updated with
assignments like "x := f(x, ...)". However this was allowed
only for a hard-wired list of functions f(), since we need to
be sure that f() will not modify the variable if it fails.
It was always envisioned that we should make that extensible,
but at the time we didn't have a good way to do so. Since
then we've invented the idea of "support functions" to allow
attaching specialized optimization knowledge to functions,
and that is a perfect mechanism for doing this.
Hence, adjust PL/pgSQL to use a support function request instead
of hard-wired logic to decide if in-place update is safe.
Preserve the previous optimizations by creating support functions
for the three functions that were previously hard-wired.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andrey Borodin <x4mmm@yandex-team.ru>
Reviewed-by: Pavel Borisov <pashkin.elfe@gmail.com>
Discussion: https://postgr.es/m/CACxu=vJaKFNsYxooSnW1wEgsAO5u_v1XYBacfVJ14wgJV_PYeg@mail.gmail.com
Follow locking behavior of ANALYZE when importing statistics. In
particular, when importing index statistics, the table must be locked
in ShareUpdateExclusive mode. Fixes bug reportd by Jian He.
ANALYZE doesn't update statistics on partitioned indexes, and the
locking requirements are slightly different for in-place updates on
partitioned indexes versus normal indexes. To be conservative, lock
both the partitioned table and the partitioned index in
ShareUpdateExclusive mode when importing stats for a partitioned
index.
Author: Corey Huinker
Reported-by: Jian He
Reviewed-by: Michael Paquier
Discussion: https://www.postgresql.org/message-id/CACJufxGreTY7qsCV8%2BBkuv0p5SXGTScgh%3DD%2BDq6%3D%2B_%3DXTp7FWg%40mail.gmail.com
Now that we generate different SQL for temporal NO ACTION vs RESTRICT
foreign keys, we should cache their query plans with different keys.
Since the key also includes the constraint oid, this shouldn't be
necessary, but we have been seeing build farm failures that suggest we
might be sometimes using a cached NO ACTION plan to implement a RESTRICT
constraint.
Author: Paul A. Jungwirth <pj@illuminatedcomputing.com>
Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
Previously, only btrees were supported as the arbiter index for
speculative insertion because there was no way to get the equality
strategy number for other index methods. We have this now (commit
c09e5a6a01), so we can support this.
At the moment, only btree supports unique indexes, so this does not
change anything in practice, but it would allow another index method
that has amcanunique to be supported.
Co-authored-by: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
Previously, only btrees were supported as the referenced unique index
for foreign keys because there was no way to get the equality strategy
number for other index methods. We have this now (commit
c09e5a6a01), so we can support this. In fact, this is now just a
special case of the existing generalized "period" foreign key
support, since that already knows how to lookup equality strategy
numbers.
Note that this does not change the requirement that the referenced
index needs to be unique, and at the moment, only btree supports that,
so this does not change anything in practice, but it would allow
another index method that has amcanunique to be supported.
Co-authored-by: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
This adds a new variant of generated columns that are computed on read
(like a view, unlike the existing stored generated columns, which are
computed on write, like a materialized view).
The syntax for the column definition is
... GENERATED ALWAYS AS (...) VIRTUAL
and VIRTUAL is also optional. VIRTUAL is the default rather than
STORED to match various other SQL products. (The SQL standard makes
no specification about this, but it also doesn't know about VIRTUAL or
STORED.) (Also, virtual views are the default, rather than
materialized views.)
Virtual generated columns are stored in tuples as null values. (A
very early version of this patch had the ambition to not store them at
all. But so much stuff breaks or gets confused if you have tuples
where a column in the middle is completely missing. This is a
compromise, and it still saves space over being forced to use stored
generated columns. If we ever find a way to improve this, a bit of
pg_upgrade cleverness could allow for upgrades to a newer scheme.)
The capabilities and restrictions of virtual generated columns are
mostly the same as for stored generated columns. In some cases, this
patch keeps virtual generated columns more restricted than they might
technically need to be, to keep the two kinds consistent. Some of
that could maybe be relaxed later after separate careful
considerations.
Some functionality that is currently not supported, but could possibly
be added as incremental features, some easier than others:
- index on or using a virtual column
- hence also no unique constraints on virtual columns
- extended statistics on virtual columns
- foreign-key constraints on virtual columns
- not-null constraints on virtual columns (check constraints are supported)
- ALTER TABLE / DROP EXPRESSION
- virtual column cannot have domain type
- virtual columns are not supported in logical replication
The tests in generated_virtual.sql have been copied over from
generated_stored.sql with the keyword replaced. This way we can make
sure the behavior is mostly aligned, and the differences can be
visible. Some tests for currently not supported features are
currently commented out.
Reviewed-by: Jian He <jian.universality@gmail.com>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Tested-by: Shlok Kyal <shlok.kyal.oss@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/a368248e-69e4-40be-9c07-6c3b5880b0a6@eisentraut.org
This commit introduces changes to track unpruned relations explicitly,
making it possible for top-level plan nodes, such as ModifyTable and
LockRows, to avoid processing partitions pruned during initial
pruning. Scan-level nodes, such as Append and MergeAppend, already
avoid the unnecessary processing by accessing partition pruning
results directly via part_prune_index. In contrast, top-level nodes
cannot access pruning results directly and need to determine which
partitions remain unpruned.
To address this, this commit introduces a new bitmapset field,
es_unpruned_relids, which the executor uses to track the set of
unpruned relations. This field is referenced during plan
initialization to skip initializing certain nodes for pruned
partitions. It is initialized with PlannedStmt.unprunableRelids,
a new field that the planner populates with RT indexes of relations
that cannot be pruned during runtime pruning. These include relations
not subject to partition pruning and those required for execution
regardless of pruning.
PlannedStmt.unprunableRelids is computed during set_plan_refs() by
removing the RT indexes of runtime-prunable relations, identified
from PartitionPruneInfos, from the full set of relation RT indexes.
ExecDoInitialPruning() then updates es_unpruned_relids by adding
partitions that survive initial pruning.
To support this, PartitionedRelPruneInfo and PartitionedRelPruningData
now include a leafpart_rti_map[] array that maps partition indexes to
their corresponding RT indexes. The former is used in set_plan_refs()
when constructing unprunableRelids, while the latter is used in
ExecDoInitialPruning() to convert partition indexes returned by
get_matching_partitions() into RT indexes, which are then added to
es_unpruned_relids.
These changes make it possible for ModifyTable and LockRows nodes to
process only relations that remain unpruned after initial pruning.
ExecInitModifyTable() trims lists, such as resultRelations,
withCheckOptionLists, returningLists, and updateColnosLists, to
consider only unpruned partitions. It also creates ResultRelInfo
structs only for these partitions. Similarly, child RowMarks for
pruned relations are skipped.
By avoiding unnecessary initialization of structures for pruned
partitions, these changes improve the performance of updates and
deletes on partitioned tables during initial runtime pruning.
Due to ExecInitModifyTable() changes as described above, EXPLAIN on a
plan for UPDATE and DELETE that uses runtime initial pruning no longer
lists partitions pruned during initial pruning.
Reviewed-by: Robert Haas <robertmhaas@gmail.com> (earlier versions)
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CA+HiwqFGkMSge6TgC9KQzde0ohpAycLQuV7ooitEEpbKB0O_mg@mail.gmail.com
This didn't actually work: the COPY succeeds, but the FREEZE
optimization isn't applied. There doesn't seem to be an easy way
to support FREEZE on foreign tables, so let's follow the precedent
established by commit 5c9a5513a3 by raising an error early. This
is arguably a bug fix, but due to the lack of reports, the minimal
discussion on the mailing list, and the potential to break existing
scripts, I am not back-patching it for now.
Author: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Zhang Mingli <zmlpostgres@gmail.com>
Discussion: https://postgr.es/m/CAA5RZ0ujeNgKpE3OrLtR%3DeJGa5LkGMekFzQTwjgw%3DrzaLufQLQ%40mail.gmail.com
Most GUCs that accept a special value to disable the feature
mention it in their GUC description. This commit adds that
information to autovacuum_vacuum_max_threshold's description.
Oversight in commit 306dc520b9.
One way autovacuum chooses tables to vacuum is by comparing the
number of updated or deleted tuples with a value calculated using
autovacuum_vacuum_threshold and autovacuum_vacuum_scale_factor.
The threshold specifies the base value for comparison, and the
scale factor specifies the fraction of the table size to add to it.
This strategy ensures that smaller tables are vacuumed after fewer
updates/deletes than larger tables, which is reasonable in many
cases but can result in infrequent vacuums on very large tables.
This is undesirable for a couple of reasons, such as very large
tables incurring a huge amount of bloat between vacuums.
This new parameter provides a way to set a limit on the value
calculated with autovacuum_vacuum_threshold and
autovacuum_vacuum_scale_factor so that very large tables are
vacuumed more frequently. By default, it is set to 100,000,000
tuples, but it can be disabled by setting it to -1. It can also be
adjusted for individual tables by changing storage parameters.
Author: Nathan Bossart <nathandbossart@gmail.com>
Co-authored-by: Frédéric Yhuel <frederic.yhuel@dalibo.com>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: Michael Banck <mbanck@gmx.net>
Reviewed-by: Joe Conway <mail@joeconway.com>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: wenhui qiu <qiuwenhuifx@gmail.com>
Reviewed-by: Vinícius Abrahão <vinnix.bsd@gmail.com>
Reviewed-by: Robert Treat <rob@xzilla.net>
Reviewed-by: Alena Rybakina <a.rybakina@postgrespro.ru>
Discussion: https://postgr.es/m/956435f8-3b2f-47a6-8756-8c54ded61802%40dalibo.com
It is possible for the inactive_since value of an invalid replication slot
to be updated multiple times, which is unexpected behavior like during the
release of the slot or at the time of restart. This is harmless because
invalid slots are not allowed to be accessed but it is not prudent to
update invalid slots. We are planning to invalidate slots due to other
reasons like idle time and it will look odd that the slot's inactive_since
displays the recent time in this field after invalidated due to idle time.
So, this patch ensures that the inactive_since field of slots is not
updated for invalid slots.
In the passing, ensure to use the same inactive_since time for all the
slots at restart while restoring them from the disk.
Author: Nisha Moond <nisha.moond412@gmail.com>
Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: Hou Zhijie <houzj.fnst@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/CABdArM7QdifQ_MHmMA=Cc4v8+MeckkwKncm2Nn6tX9wSCQ-+iw@mail.gmail.com
This commit allows transformation of OR-clauses into SAOP's for index scans
within nested loop joins. That required the following changes.
1. Make match_orclause_to_indexcol() and group_similar_or_args() understand
const-ness in the same way as match_opclause_to_indexcol(). This
generally makes our approach more uniform.
2. Make match_join_clauses_to_index() pass OR-clauses to
match_clause_to_index().
3. Also switch match_join_clauses_to_index() to use list_append_unique_ptr()
for adding clauses to *joinorclauses. That avoids possible duplicates
when processing the same clauses with different indexes. Previously such
duplicates were elimited in match_clause_to_index(), but now
group_similar_or_args() each time generates distinct copies of grouped
OR clauses.
Discussion: https://postgr.es/m/CAPpHfdv%2BjtNwofg-p5z86jLYZUTt6tR17Wy00ta0dL%3DwHQN3ZA%40mail.gmail.com
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Alena Rybakina <a.rybakina@postgrespro.ru>
Reviewed-by: Pavel Borisov <pashkin.elfe@gmail.com>
Since d4378c0005, match_clause_to_indexcol() doesn't always return NULL
for an OR clause. This commit reflects that in the function header comment.
Reported-by: Pavel Borisov <pashkin.elfe@gmail.com>
This commit adds WAL IO stats to both pg_stat_io view and per-backend IO
statistics (pg_stat_get_backend_io()). This change is possible since
f92c854cf4, as WAL IO is not counted in blocks in some code paths
where its stats data is measured (like WAL read in xlogreader.c).
IOContext gains IOCONTEXT_INIT and IOObject IOOBJECT_WAL, with the
following combinations allowed:
- IOOBJECT_WAL/IOCONTEXT_NORMAL is used to track I/O operations done on
already-created WAL segments.
- IOOBJECT_WAL/IOCONTEXT_INIT is used for tracking I/O operations done
when initializing WAL segments.
The core changes are done in pg_stat_io.c, backend statistics inherit
them. Backend statistics and pg_stat_io are now available for the WAL
writer, the WAL receiver and the WAL summarizer processes.
I/O timing data is controlled by the GUC track_io_timing, like the
existing data of pg_stat_io for consistency. The timings related to
IOOBJECT_WAL show up if the GUC is enabled (disabled by default).
Bump pgstats file version, due to the additions in IOObject and
IOContext, impacting the amount of data written for the fixed-numbered
IO stats kind in the pgstats file.
Author: Nazir Bilal Yavuz
Reviewed-by: Bertrand Drouvot, Nitin Jadhav, Amit Kapila, Michael
Paquier, Melanie Plageman, Bharath Rupireddy
Discussion: https://postgr.es/m/CAN55FZ3AiQ+ZMxUuXnBpd0Rrh1YhwJ5FudkHg=JU0P+-W8T4Vg@mail.gmail.com
This turns GistTranslateCompareType() into a callback function of the
gist index AM instead of a standalone function. The existing callers
are changed to use IndexAmTranslateCompareType(). This then makes
that code not hardcoded toward gist.
This means in particular that the temporal keys code is now
independent of gist. Also, this generalizes commit 74edabce7a, so
other index access methods other than the previously hardcoded ones
could now work as REPLICA IDENTITY in a logical replication
subscriber.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Co-authored-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
This commit adds more documentation to pgstat_count_io_op_time() in
pgstat_io.c, explaining its internals for pgstat_count_buffer_*(),
pgBufferUsage and the contexts where these are used.
Extracted from a larger patch by the same author.
Author: Nazir Bilal Yavuz
Discussion: https://postgr.es/m/CAN55FZ3AiQ+ZMxUuXnBpd0Rrh1YhwJ5FudkHg=JU0P+-W8T4Vg@mail.gmail.com
For each Index AM, provide a mapping between operator strategies and
the system-wide generic concept of a comparison type. For example,
for btree, BTLessStrategyNumber maps to and from COMPARE_LT. Numerous
places in the planner and executor think directly in terms of btree
strategy numbers (and a few in terms of hash strategy numbers.) These
should be converted over subsequent commits to think in terms of
CompareType instead. (This commit doesn't make any use of this API
yet.)
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
logging_collector was only mentioning stderr and csvlog, and forgot
about jsonlog. Oversight in dc686681e0, that has added support for
jsonlog in log_destination.
While on it, the description in the GUC table is tweaked to be more
consistent with the documentation and postgresql.conf.sample.
Author: Umar Hayat
Reviewed-by: Ashutosh Bapat, Tom Lane
Discussion: https://postgr.es/m/CAD68Dp1K_vBYqBEukHw=1jF7e76t8aszGZTFL2ugi=H7r=a7MA@mail.gmail.com
Backpatch-through: 13
Follow up to commit 630f9a43ce. The previous name had become
confusing, because it doesn't actually translate a strategy number but
a CompareType into a strategy number. We might add the inverse at
some point, which would then probably be called something like
GistTranslateStratnum.
Reviewed-by: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
Whilst working on commit 041e8b95b I happened to notice that
parallel_vacuum_main() assigns directly to the maintenance_work_mem
GUC. This is definitely not per project conventions, so I tried to
fix it to use SetConfigOption(). But that fails with "parameter
cannot be set during a parallel operation". It doesn't seem worth
working on a cleaner answer, at least not till we have a few more
instances of similar problems. But add some commentary, just so
nobody gets the idea that this is an approved way to set a GUC.
When syslogger.c was first written, we didn't want to assume that
all platforms have 64-bit ftello. But we've been assuming that
since v13 (cf commit 799d22461), so let's use that in syslogger.c
and allow log_rotation_size to range up to INT_MAX kilobytes.
The old code effectively limited log_rotation_size to 2GB regardless
of platform. While nobody's complained, that doesn't seem too far
away from what might be thought reasonable these days.
I noticed this while searching for instances of "1024L" in connection
with commit 041e8b95b. These were the last such instances.
(We still have instances of L-suffixed literals, but most of them
are associated with wait intervals for pg_usleep or similar functions.
I don't see any urgent reason to change that.)
Consistently use "Size" (or size_t, or in some places int64 or double)
as the type for variables holding memory allocation sizes. In most
places variables' data types were fine already, but we had an ancient
habit of computing bytes from kilobytes-units GUCs with code like
"work_mem * 1024L". That risks overflow on Win64 where they did not
make "long" as wide as "size_t". We worked around that by restricting
such GUCs' ranges, so you couldn't set work_mem et al higher than 2GB
on Win64. This patch removes that restriction, after replacing such
calculations with "work_mem * (Size) 1024" or variants of that.
It should be noted that this patch was constructed by searching
outwards from the GUCs that have MAX_KILOBYTES as upper limit.
So I can't positively guarantee there are no other places doing
memory-size arithmetic in int or long variables. I do however feel
pretty confident that increasing MAX_KILOBYTES on Win64 is safe now.
Also, nothing in our code should be dealing in multiple-gigabyte
allocations without authorization from a relevant GUC, so it seems
pretty likely that this search caught everything that could be at
risk of overflow.
Author: Vladlen Popolitov <v.popolitov@postgrespro.ru>
Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/1a01f0-66ec2d80-3b-68487680@27595217
Future SASL mechanism, like OAUTHBEARER, will use this as a limit on
token messages coming from the client, so promote it to the header
file to make it available.
This patch is extracted from a larger body of work aimed at adding
support for OAUTHBEARER in libpq.
Author: Jacob Champion <jacob.champion@enterprisedb.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/CAOYmi+kJqzo6XsR9TEhvVfeVNQ-TyFM5LATypm9yoQVYk=4Wrw@mail.gmail.com
This commit builds on the prior change that moved PartitionPruneInfos
out of individual plan nodes into a list in PlannedStmt, making it
possible to initialize PartitionPruneStates without traversing the
plan tree and perform runtime initial pruning before ExecInitNode()
initializes the plan trees. These tasks are now handled in a new
routine, ExecDoInitialPruning(), which is called by InitPlan()
before calling ExecInitNode() on various plan trees.
ExecDoInitialPruning() performs the initial pruning and saves the
result -- a Bitmapset of indexes for surviving child subnodes -- in
es_part_prune_results, a list in EState.
PartitionPruneStates created for initial pruning are stored in
es_part_prune_states, another list in EState, for later use during
exec pruning. Both lists are parallel to es_part_prune_infos, which
holds the PartitionPruneInfos from PlannedStmt, enabling shared
indexing.
PartitionPruneStates initialized in ExecDoInitialPruning() now
include only the PartitionPruneContexts for initial pruning steps.
Exec pruning contexts are initialized later in
ExecInitPartitionExecPruning() when the parent plan node is
initialized, as the exec pruning step expressions depend on the parent
node's PlanState.
The existing function PartitionPruneFixSubPlanMap() has been
repurposed for this initialization to avoid duplicating a similar
loop structure for finding PartitionedRelPruningData to initialize
exec pruning contexts for. It has been renamed to
InitExecPruningContexts() to reflect its new primary responsibility.
The original logic to "fix subplan maps" remains intact but is now
encapsulated within the renamed function.
This commit removes two obsolete Asserts in partkey_datum_from_expr().
The ExprContext used for pruning expression evaluation is now
independent of the parent PlanState, making these Asserts unnecessary.
By centralizing pruning logic and decoupling it from the plan
initialization step (ExecInitNode()), this change sets the stage for
future patches that will use the result of initial pruning to
save the overhead of redundant processing for pruned partitions.
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CA+HiwqFGkMSge6TgC9KQzde0ohpAycLQuV7ooitEEpbKB0O_mg@mail.gmail.com
Once a replication slot is invalidated, it cannot be altered or used to
fetch changes. However, a process could still acquire an invalid slot and
fail later.
For example, if a process acquires a logical slot that was invalidated due
to wal_removed, it will eventually fail in CreateDecodingContext() when
attempting to access the removed WAL. Similarly, for physical replication
slots, even if the slot is invalidated and invalidation_reason is set to
wal_removed, the walsender does not currently check for invalidation when
starting physical replication. Instead, replication starts, and an error
is only reported later while trying to access WAL. Similarly, we prohibit
modifying slot properties for invalid slots but give the error for the
same after acquiring the slot.
This patch improves error handling by detecting invalid slots earlier at
the time of slot acquisition which is the first step. This also helped in
unifying different ERROR messages at different places and gave a
consistent message for invalid slots. This means that the message for
invalid slots will change to a generic message.
This will also be helpful for future patches where we are planning to
invalidate slots due to more reasons like idle_timeout because we don't
have to modify multiple places in such cases and avoid the chances of
missing out on a particular place.
Author: Nisha Moond <nisha.moond412@gmail.com>
Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/CABdArM6pBL5hPnSQ+5nEVMANcF4FCH7LQmgskXyiLY75TMnKpw@mail.gmail.com
This allows users of the cumulative statistics to drop entries in the
shared hash stats table, deleting as well local references. Callers of
this function can optionally define a callback able to filter which
entries to drop, similarly to pgstat_reset_matching_entries() with its
callback do_reset().
pgstat_drop_all_entries() is refactored so as it uses this new function.
Author: Lukas Fitti
Discussion: https://postgr.es/m/CAP53PkwuFbo3NkwZgxwNRMjMfqPEqidD-SggaoQ4ijotBVLJAA@mail.gmail.com
This change adapts these functions to the machine's address width
without depending on "long" to be the right size. (It isn't on
Win64, for example.) While it seems unlikely anyone would care
to run with a stack depth limit exceeding 2GB, this is part of a
general push to avoid using type "long" to represent memory sizes.
It's convenient to use ssize_t rather than the perhaps-more-obvious
choice of size_t/Size, because the code involved depends on working
with a signed data type. Our MAX_KILOBYTES limit already ensures
that ssize_t will be sufficient to represent the maximum value of
max_stack_depth.
Extracted from a larger patch by Vladlen, plus additional hackery
by me.
Author: Vladlen Popolitov <v.popolitov@postgrespro.ru>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/1a01f0-66ec2d80-3b-68487680@27595217
smgrDoPendingSyncs had two distinct risks of integer overflow while
deciding which way to ensure durability of a newly-created relation.
First, it accumulated the total size of all forks in a variable of
type BlockNumber (uint32). While we restrict an individual fork's
size to fit in that, I don't believe there's such a restriction on
all of them added together. Second, it proceeded to multiply the
sum by BLCKSZ, which most certainly could overflow a uint32.
(The exact expression is total_blocks * BLCKSZ / 1024. The
compiler might choose to optimize that to total_blocks * 8,
which is not at quite as much risk of overflow as a literal
reading would be, but it's still wrong.)
If an overflow did occur it could lead to a poor choice to
shove a very large relation into WAL instead of fsync'ing it.
This wouldn't be fatal, but it could be inefficient.
Change total_blocks to uint64 which should be plenty, and
rearrange the comparison calculation to be overflow-safe.
I noticed this while looking for ramifications of the proposed
change in MAX_KILOBYTES. It's not entirely clear to me why
wal_skip_threshold is limited to MAX_KILOBYTES in the
first place, but in any case this code is unsafe regardless
of the range of wal_skip_threshold.
Oversight in c6b92041d which introduced wal_skip_threshold,
so back-patch to v13.
Discussion: https://postgr.es/m/1a01f0-66ec2d80-3b-68487680@27595217
Backpatch-through: 13
Add BitmapTableScanSetup(), a helper which contains all of the code that
must be done on every scan of the table in a bitmap table scan. This
includes scanning the index, building the bitmap, and setting up the
scan descriptors.
Pushing this setup into a helper function makes BitmapHeapNext() more
readable.
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/CAN55FZ1vXu%2BZdT0_MM-i1vbTdfHHf0KR3cK6R5gs6dNNNpyrJw%40mail.gmail.com
Instead of deciding at runtime whether to read from casetest.value
or caseValue_datum, split EEOP_CASE_TESTVAL into two opcodes and
make the decision during expression compilation. Similarly for
EEOP_DOMAIN_TESTVAL. This actually results in net less code,
mainly because llvmjit_expr.c's code for handling these opcodes
gets shorter. The performance gain is doubtless negligible, but
this seems worth changing anyway on grounds of simplicity and
understandability.
Author: Andreas Karlsson <andreas@proxel.se>
Co-authored-by: Xing Guo <higuoxing@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CACpMh+AiBYAWn+D1aU7Rsy-V1tox06Cbc0H3qA7rwL5zdJ=anQ@mail.gmail.com
This moves PartitionPruneInfo from plan nodes to PlannedStmt,
simplifying traversal by centralizing all PartitionPruneInfo
structures in a single list in it, which holds all instances for the
main query and its subqueries. Instead of plan nodes (Append or
MergeAppend) storing PartitionPruneInfo pointers, they now reference
an index in this list.
A bitmapset field is added to PartitionPruneInfo to store the RT
indexes corresponding to the apprelids field in Append or MergeAppend.
This allows execution pruning logic to verify that it operates on the
correct plan node, mainly to facilitate debugging.
Duplicated code in set_append_references() and
set_mergeappend_references() is refactored into a new function,
register_pruneinfo(). This updates RT indexes by applying rtoffet
and adds PartitionPruneInfo to the global list in PlannerGlobal.
By allowing pruning to be performed without traversing the plan tree,
this change lays the groundwork for runtime initial pruning to occur
independently of plan tree initialization.
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org> (earlier version)
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CA+HiwqFGkMSge6TgC9KQzde0ohpAycLQuV7ooitEEpbKB0O_mg@mail.gmail.com
In view of the issue fixed in commit 0da39aa76, it no longer seems
like a great idea for coerce_to_domain() to offer to perform a lookup
that its caller probably should have done already. The caller should
be providing a value of the domain's base type, so it's hard to
envision a valid case where it hasn't looked up that type. After
0da39aa76 there is only one caller using the option for internal
lookup, and that one can trivially be rearranged to not do that.
So this seems more like a bug-encouraging misfeature than a useful
shortcut; let's get rid of it (in HEAD only, there's no need to
break any external callers in back branches).
Discussion: https://postgr.es/m/1865579.1738113656@sss.pgh.pa.us
If a column is omitted in an INSERT, and there's no column default,
the code in preptlist.c generates a NULL Const to be inserted.
Furthermore, if the column is of a domain type, we wrap the Const
in CoerceToDomain, so as to throw a run-time error if the domain
has a NOT NULL constraint. That's fine as far as it goes, but
there are two problems:
1. We're being sloppy about the type/typmod that the Const is
labeled with. It really should have the domain's base type/typmod,
since it's the input to CoerceToDomain not the output. This can
result in coerce_to_domain inserting a useless length-coercion
function (useless because it's being applied to a null). The
coercion would typically get const-folded away later, but it'd
be better not to create it in the first place.
2. We're not applying expression preprocessing (specifically,
eval_const_expressions) to the resulting expression tree.
The planner's primary expression-preprocessing pass already happened,
so that means the length coercion step and CoerceToDomain node miss
preprocessing altogether.
This is at the least inefficient, since it means the length coercion
and CoerceToDomain will actually be executed for each inserted row,
though they could be const-folded away in most cases. Worse, it
seems possible that missing preprocessing for the length coercion
could result in an invalid plan (for example, due to failing to
perform default-function-argument insertion). I'm not aware of
any live bug of that sort with core datatypes, and it might be
unreachable for extension types as well because of restrictions of
CREATE CAST, but I'm not entirely convinced that it's unreachable.
Hence, it seems worth back-patching the fix (although I only went
back to v14, as the patch doesn't apply cleanly at all in v13).
There are several places in the rewriter that are building null
domain constants the same way as preptlist.c. While those are
before the planner and hence don't have any reachable bug, they're
still applying a length coercion that will be const-folded away
later, uselessly wasting cycles. Hence, make a utility routine
that all of these places can call to do it right.
Making this code more careful about the typmod assigned to the
generated NULL constant has visible but cosmetic effects on some
of the plans shown in contrib/postgres_fdw's regression tests.
Discussion: https://postgr.es/m/1865579.1738113656@sss.pgh.pa.us
Backpatch-through: 14
These functions tried to check the state of the buffer's content lock
even for local buffers. Since we don't use the content lock for a
local buffer, that would lead to a "false" result from
LWLockHeldByMeInMode, which would mean a misleading "false" answer
from BufferIsExclusiveLocked (we'd rather that case always return
"true") or an assertion failure in BufferIsDirty.
The core code never applies these two functions to local buffers,
and apparently no extensions do either, since we've not heard
complaints. Still, in the name of future-proofing, let's fix
them to act as though a pinned local buffer is content-locked.
Author: Srinath Reddy <srinath2133@gmail.com>
Discussion: https://postgr.es/m/19396ef77f8.1098c4a1810508.2255483659262451647@zohocorp.com
The column added in commit e65dbc9927, pubgencols_type, was inconsistent
with the naming conventions of other columns in the pg_publication
catalog.
Author: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Discussion: https://postgr.es/m/CALDaNm1u-ufVOW-RUsXSooqzkpohxfZYy=z78fbcr_9Pq5hbCg@mail.gmail.com
This commit adds four fields to the statistics of relations, aggregating
the amount of time spent for each operation on a relation:
- total_vacuum_time, for manual vacuum.
- total_autovacuum_time, for vacuum done by the autovacuum daemon.
- total_analyze_time, for manual analyze.
- total_autoanalyze_time, for analyze done by the autovacuum daemon.
This gives users the option to derive the average time spent for these
operations with the help of the related "count" fields.
Bump catalog version (for the catalog changes) and PGSTAT_FILE_FORMAT_ID
(for the additions in PgStat_StatTabEntry).
Author: Sami Imseih
Reviewed-by: Bertrand Drouvot, Michael Paquier
Discussion: https://postgr.es/m/CAA5RZ0uVOGBYmPEeGF2d1B_67tgNjKx_bKDuL+oUftuoz+=Y1g@mail.gmail.com
A ParseState exists in ATPrepAlterColumnType() since its introduction
in 077db40fa1, and it has never relied on a query string that could be
used to point at a location in the origin string on error.
The output of some regression tests are updated, showing the error
location where applicable. Six error strings are upgraded with the
error location.
Author: Jian He
Discussion: https://postgr.es/m/CACJufxGfbPfWLjcEz33G9eW_epDW0UDi2H05i9eSTPKGJ4rxSA@mail.gmail.com
For commit b663b9436e I thought this was useless, but turns out not to
be for the case where a partitioned table has two identical foreign key
constraints which can both be matched by the same constraint in a
partition during attach. This CCI makes the match search for the second
constraint in the parent ignore the constraint in the child that has
already been matched by the first constraint in the parent.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/c599253c-1ccd-4161-80fc-c9065e037a09@gmail.com
The right mix of DDL and VACUUM could corrupt a catalog page header such
that PageIsVerified() durably fails, requiring a restore from backup.
This affects only catalogs that both have a syscache and have DDL code
that uses syscache tuples to construct updates. One of the test
permutations shows a variant not yet fixed.
This makes !TransactionIdIsValid(TM_FailureData.xmax) possible with
TM_Deleted. I think core and PGXN are indifferent to that.
Per bug #17821 from Alexander Lakhin. Back-patch to v13 (all supported
versions). The test case is v17+, since it uses INJECTION_POINT.
Discussion: https://postgr.es/m/17821-dd8c334263399284@postgresql.org
The main motivation for this change is to have a process that can serialize
stats after all other processes have terminated. Serializing stats already
happens in checkpointer, even though walsenders can be active longer.
The only reason the current shutdown sequence does not actively cause problems
is that walsender currently does not generate any stats. However, there is an
upcoming patch changing that.
Another need for this change originates in the AIO patchset, where IO
workers (which, in some edge cases, can emit stats of their own) need to run
while the shutdown checkpoint is being written.
This commit changes the shutdown sequence so checkpointer is signalled (via
SIGINT) to trigger writing the shutdown checkpoint without also causing
checkpointer to exit. Once checkpointer wrote the shutdown checkpoint it
notifies postmaster via PMSIGNAL_XLOG_IS_SHUTDOWN and waits for the
termination signal (SIGUSR2, as before). Checkpointer now is terminated after
all children, other than dead-end children and logger, have been terminated,
tracked using the new PM_WAIT_CHECKPOINTER PMState.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/kgng5nrvnlv335evmsuvpnh354rw7qyazl73kdysev2cr2v5zu@m3cfzxicm5kp
The sizeof() call should reference buffer.data, because that's the
buffer we're reading data into, not the whole PGAlignedBuffer union.
This was introduced by 44cac93464, which replaced the simple buffer
with a PGAlignedBuffer field.
It's benign, because the buffer is the largest field of the union, so
the sizes are the same. But it's easy to trip over this in a patch, so
fix and backpatch. Commit 44cac93464 went into 12, but that's EOL.
Backpatch-through: 13
Discussion: https://postgr.es/m/928bdab1-6567-449f-98c4-339cd2203b87@vondra.me
Useful for caseless matching. Similar to LOWER(), but avoids edge-case
problems with using LOWER() for caseless matching.
For collations that support it, CASEFOLD() handles characters with
more than two case variations or multi-character case variations. Some
characters may fold to uppercase. The results of case folding are also
more stable across Unicode versions than LOWER() or UPPER().
Discussion: https://postgr.es/m/a1886ddfcd8f60cb3e905c93009b646b4cfb74c5.camel%40j-davis.com
Reviewed-by: Ian Lawrence Barwick
Comments and code stated that we expect checkpointer to have been signalled in
case of immediate shutdown / fatal errors, but didn't treat archiver and
walsenders the same. That doesn't seem right.
I had started digging through the history to see where this oddity was
introduced, but it's not the fault of a single commit.
Instead treat archiver, checkpointer, and walsenders the same.
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/kgng5nrvnlv335evmsuvpnh354rw7qyazl73kdysev2cr2v5zu@m3cfzxicm5kp
This includes some behavioral changes:
- Previously PM_WAIT_XLOG_ARCHIVAL wasn't handled in HandleFatalError(), that
doesn't seem quite right.
- Previously a fatal error in PM_WAIT_XLOG_SHUTDOWN lead to jumping back to
PM_WAIT_BACKENDS, no we go to PM_WAIT_DEAD_END. Jumping backwards doesn't
seem quite right and we didn't do so when checkpointer failed to fork during
a shutdown.
- Previously a checkpointer fork failure didn't call SetQuitSignalReason(),
which would lead to quickdie() reporting
"terminating connection because of unexpected SIGQUIT signal"
which seems even worse than the PMQUIT_FOR_CRASH message. If I saw that in
the log I'd suspect somebody outside of postgres sent SIGQUITs
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/kgng5nrvnlv335evmsuvpnh354rw7qyazl73kdysev2cr2v5zu@m3cfzxicm5kp
There are two places switching to FatalError mode, behaving somewhat
differently. An upcoming commit will introduce a third. That doesn't seem seem
like a good idea.
This commit just moves the FatalError related code from HandleChildCrash()
into its own function, a subsequent commit will evolve the state machine
change to be suitable for other callers.
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/kgng5nrvnlv335evmsuvpnh354rw7qyazl73kdysev2cr2v5zu@m3cfzxicm5kp
Previously HandleChildCrash() skipped logging and signalling child exits if
already in an immediate shutdown or in FatalError state, but still
transitioned server state in response to a crash. That's redundant.
In the other place we transition to FatalError, we do take care to not do so
when already in FatalError state.
To make it easier to combine different paths for entering FatalError state,
only do so once in HandleChildCrash().
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/kgng5nrvnlv335evmsuvpnh354rw7qyazl73kdysev2cr2v5zu@m3cfzxicm5kp
The motivation for this change is that a future commit will use SIGINT for
another purpose (postmaster requesting WAL access to be shut down) and that
there no other signals that we could readily use (see code comment for the
reason why SIGTERM shouldn't be used). But it's also a tad nicer / more
efficient to use SetLatch(), as it avoids sending signals when checkpointer
already is busy.
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/kgng5nrvnlv335evmsuvpnh354rw7qyazl73kdysev2cr2v5zu@m3cfzxicm5kp
Formerly, these cases threw an error "cannot cast jsonb null to type
<whatever>". That seems less than helpful though. It's also
inconsistent with the behavior of the ->> operator, which translates
JSON null to SQL NULL, as do some other jsonb functions.
Discussion: https://postgr.es/m/3851203.1722552717@sss.pgh.pa.us
We thought that this condition was unreachable in ExitPostmaster,
but actually it's possible if you have both a misconfigured locale
setting and some other mistake that causes PostmasterMain to bail
out before reaching its own check of pthread_is_threaded_np().
Given the lack of other reports, let's not ask for bug reports if
this occurs; instead just give the same hint as in PostmasterMain.
Bug: #18783
Reported-by: anani191181515@gmail.com
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/18783-d1873b95a59b9103@postgresql.org
Discussion: https://postgr.es/m/206317.1737656533@sss.pgh.pa.us
Backpatch-through: 13
With deferred triggers, it is possible that the current role changes
between the time when the trigger is queued and the time it is
executed (for example, the triggering data modification could have
been executed in a SECURITY DEFINER function).
Up to now, deferred trigger functions would run with the current role
set to whatever was active at commit time. That does not matter for
foreign-key constraints, whose correctness doesn't depend on the
current role. But for user-written triggers, the current role
certainly can matter.
Hence, fix things so that AFTER triggers are fired under the role
that was active when they were queued, matching the behavior of
BEFORE triggers which would have actually fired at that time.
(If the trigger function is marked SECURITY DEFINER, that of course
overrides this, as it always has.)
This does not create any new security exposure: if you do DML on a
table owned by a hostile user, that user has always had various ways
to exploit your permissions, such as the aforementioned BEFORE
triggers, default expressions, etc. It might remove some security
exposure, because the old behavior could potentially expose some
other role besides the one directly modifying the table.
There was discussion of making a larger change, such as running as
the trigger's owner. However, that would break the common idiom of
capturing the value of CURRENT_USER in a trigger for auditing/logging
purposes. This change will make no difference in the typical scenario
where the current role doesn't change before commit.
Arguably this is a bug fix, but it seems too big a semantic change
to consider for back-patching.
Author: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: Joseph Koshakow <koshy44@gmail.com>
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Discussion: https://postgr.es/m/77ee784cf248e842f74588418f55c2931e47bd78.camel@cybertec.at
When scanning existing AfterTriggerSharedData records in search
of a match to the event being queued, we were examining the
records from oldest to newest. But it makes more sense to do
the opposite. The newest record is likely to be from the current
query, while the oldest is likely to be from some previous command
in the same transaction, which will likely have different details.
There aren't expected to be very many active AfterTriggerSharedData
records at once, so that this change is unlikely to make any
spectacular difference. Still, having added a nontrivially-expensive
bms_equal call to this loop yesterday, I feel a need to shave cycles
where possible.
Discussion: https://postgr.es/m/4166712.1737583961@sss.pgh.pa.us
This feature was intentionally omitted when FKs were first implemented
for partitioned tables, and had been requested a few times; the
usefulness is clear.
Validation can happen for each partition individually, which is useful
to contain the number of locks held and the duration; or it can be
executed for the partitioning hierarchy as a single command, which
validates all child constraints that haven't been validated already.
This is also useful to implement NOT ENFORCED constraints on top.
Author: Amul Sul <sulamul@gmail.com>
Discussion: https://postgr.es/m/CAAJ_b96Bp=-ZwihPPtuaNX=SrZ0U6ZsXD3+fgARO0JuKa8v2jQ@mail.gmail.com
The current boolean publish_generated_columns option only supports a
binary choice, which is insufficient for future enhancements where
generated columns can be of different types (e.g., stored or virtual). The
supported values for the publish_generated_columns option are 'none' and
'stored'.
Author: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/d718d219-dd47-4a33-bb97-56e8fc4da994@eisentraut.org
Discussion: https://postgr.es/m/B80D17B2-2C8E-4C7D-87F2-E5B4BE3C069E@gmail.com
We've long had roman-numeral output support in to_char(),
but lacked the reverse conversion. Here it is.
Author: Hunaid Sohail <hunaidpgml@gmail.com>
Reviewed-by: Maciek Sakrejda <m.sakrejda@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CAMWA6ybh4M1VQqpmnu2tfSwO+3gAPeA8YKnMHVADeB=XDEvT_A@mail.gmail.com
This patch fixes two distinct errors that both ultimately trace
to commit 71d60e2aa, which added the ats_modifiedcols field.
The more severe error is that ats_modifiedcols wasn't accounted for
in afterTriggerAddEvent's scanning loop that looks for a pre-existing
duplicate AfterTriggerSharedData. Thus, a new event could be
incorrectly matched to an AfterTriggerSharedData that has a different
value of ats_modifiedcols, resulting in the wrong tg_updatedcols
bitmap getting passed to the trigger whenever it finally gets fired.
We'd not noticed because (a) few triggers consult tg_updatedcols,
and (b) we had no tests exercising a case where such a trigger was
called as an AFTER trigger. In the test case added by this commit,
contrib/lo's trigger fails to remove a large object when expected
because (without this fix) it thinks the LO OID column hasn't changed.
The other problem was introduced by commit ce5aaea8c, which copied the
modified-columns bitmap into trigger-related storage. It made a copy
for every trigger event, whereas what we really want is to make a new
copy only when we make a new AfterTriggerSharedData entry. (We could
imagine adding extra logic to reduce the number of bitmap copies still
more, but it doesn't look worthwhile at the moment.) In a simple test
of an UPDATE of 10000000 rows with a single AFTER trigger, this thinko
roughly tripled the amount of memory consumed by the pending-triggers
data structures, from 160446744 to 480443440 bytes.
Fixing the first problem requires introducing a bms_equal() call into
afterTriggerAddEvent's scanning loop, which is slightly annoying from
a speed perspective. However, getting rid of the excessive bms_copy()
calls from the second problem balances that out; overall speed of
trigger operations is the same or slightly better, in my tests.
Discussion: https://postgr.es/m/3496294.1737501591@sss.pgh.pa.us
Backpatch-through: 13
Most were introduced in the 17 timeframe. The ones in wparser_def.c are
very old.
I also changed "JSON path expression for column \"%s\" should return
single item without wrapper" to "JSON path expression for column \"%s\"
must return single item when no wrapper is requested" to avoid
ambiguity.
Backpatch to 17.
Crickets: https://postgr.es/m/202501131819.26ors7oouafu@alvherre.pgsql
In common cases, foreign keys are defined on the toplevel partitioned
table; but if instead one is defined on a partition and references a
partitioned table, and the referencing partition is detached, we would
examine the pg_constraint row on the partition being detached, and fail
to realize that the sub-constraints must be left alone. This causes the
ALTER TABLE DETACH process to fail with
ERROR: could not find ON INSERT check triggers of foreign key constraint NNN
This is similar but not quite the same as what was fixed by
53af9491a0. This bug doesn't affect branches earlier than 15, because
the detach procedure was different there, so we only backpatch down to
15.
Fix by skipping such modifying constraints that are children of other
constraints being detached.
Author: Amul Sul <sulamul@gmail.com>
Diagnosys-by: Sami Imseih <samimseih@gmail.com>
Discussion: https://postgr.es/m/CAAJ_b97GuPh6wQPbxQS-Zpy16Oh+0aMv-w64QcGrLhCOZZ6p+g@mail.gmail.com
If a referenced UPDATE changes the temporal start/end times, shrinking
the span the row is valid, we get a false return from
ri_Check_Pk_Match(), but overlapping references may still be valid, if
their reference didn't overlap with the removed span.
We need to consider what span(s) are still provided in the referenced
table. Instead of returning that from ri_Check_Pk_Match(), we can
just look it up in the main SQL query.
Reported-by: Sam Gabrielsson <sam@movsom.se>
Author: Paul Jungwirth <pj@illuminatedcomputing.com>
Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
This commit refactors ExecScan() by moving its tuple-fetching,
filtering, and projection logic into an inline-able function,
ExecScanExtended(), defined in src/include/executor/execScan.h.
ExecScanExtended() accepts parameters for EvalPlanQual state,
qualifiers (ExprState), and projection (ProjectionInfo).
Specialized variants of the execution function of a given Scan node
(for example, ExecSeqScan() for SeqScan) can then pass const-NULL for
unused parameters. This allows the compiler to inline the logic and
eliminate unnecessary branches or checks. Each variant function thus
contains only the necessary code, optimizing execution for scans
where these features are not needed.
The variant function to be used is determined in the ExecInit*()
function of the node and assigned to the ExecProcNode function pointer
in the node's PlanState, effectively turning runtime checks and
conditional branches on the NULLness of epqstate, qual, and projInfo
into static ones, provided the compiler successfully eliminates
unnecessary checks from the inlined code of ExecScanExtended().
Currently, only ExecSeqScan() is modified to take advantage of this
inline-ability. Other Scan nodes might benefit from such specialized
variant functions but that is left as future work.
Benchmarks performed by Junwang Zhao, David Rowley and myself show up
to a 5% reduction in execution time for queries that rely heavily on
Seq Scans. The most significant improvements were observed in
scenarios where EvalPlanQual, qualifiers, and projection were not
required, but other cases also benefit from reduced runtime overhead
due to the inlining and removal of unnecessary code paths.
The idea for this patch first came from Andres Freund in an off-list
discussion. The refactoring approach implemented here is based on a
proposal by David Rowley, significantly improving upon the patch I
(amitlan) initially proposed.
Suggested-by: Andres Freund <andres@anarazel.de>
Co-authored-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Tested-by: Junwang Zhao <zhjwpku@gmail.com>
Tested-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CA+HiwqGaH-otvqW_ce-paL=96JvU4j+Xbuk+14esJNDwefdkOg@mail.gmail.com
9aea73fc61 has added support for backend statistics, relying on
PgStat_EntryRef->pending for its data pending for flush. This design
lacks in flexibility, because the pending list does some memory
allocation, making it unsuitable if incrementing counters in critical
sections.
Pending data of backend statistics is reworked so the implementation
does not depend on PgStat_EntryRef->pending anymore, relying on a static
area of memory to store the counters that are flushed when stats are
reported to the pgstats dshash. An advantage of this approach is to
allow the pending data to be manipulated in critical sections; some
patches are under discussion and require that.
The pending data is tracked by PendingBackendStats, local to
pgstat_backend.c. Two routines are introduced to allow IO statistics to
update the backend-side counters. have_static_pending_cb and
flush_static_cb are used for the flush, instead of flush_pending_cb.
Author: Bertrand Drouvot, Michael Paquier
Discussion: https://postgr.es/m/66efowskppsns35v5u2m7k4sdnl7yoz5bo64tdjwq7r5lhplrz@y7dme5xwh2r5
The two callbacks have_fixed_pending_cb and flush_fixed_cb have been
introduced in fc415edf8c to provide a way for fixed-numbered
statistics to control the flush of their data. These are renamed to
respectively have_static_pending_cb and flush_static_cb. The
restriction that these only apply to fixed-numbered stats is removed.
A follow-up patch will make use of them for backend statistics. This
stats kind is variable-numbered, and patches are under discussion to
track WAL data for IO and backend stats which cannot use
PgStat_EntryRef->pending as pending data would be touched in critical
sections, where no memory allocation can happen.
Per discussion with Andres Freund.
Author: Bertrand Drouvot
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/66efowskppsns35v5u2m7k4sdnl7yoz5bo64tdjwq7r5lhplrz@y7dme5xwh2r5
If a WaitEventSetWait() caller asks for multiple events, an already set
latch would previously prevent other events from being reported at the
same time. Now, we'll also poll the kernel for other events that would
fit in the caller's output buffer with a zero wait time. This policy
change doesn't affect callers that ask for only one event.
The main caller affected is the postmaster. If its latch is set
extremely frequently by backends launching workers and workers exiting,
we don't want it to handle only those jobs and ignore incoming client
connections.
Back-patch to 16 where the postmaster began using the API. The
fast-return policy changed here is older than that, but doesn't cause
any known problems in earlier releases.
Reported-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/Z1n5UpAiGDmFcMmd%40nathan
XLogPageRead() checks immediately for an invalid WAL record header on a
standby, to be able to handle the case of continuation records that need
to be read across two different sources. As written, the check was too
generic, applying to any target LSN. Based on an analysis by Kyotaro
Horiguchi, what really matters is to make sure that the page header is
checked when attempting to read a LSN at the boundary of a segment, to
handle the case of a continuation record that spawns across multiple
pages when dealing with multiple segments, as WAL receivers are spawned
they request WAL from the beginning of a segment. This fix has been
proposed by Kyotaro Horiguchi.
This could cause standbys to loop infinitely when dealing with a
continuation record during a timeline jump, in the case where the
contents of the record in the follow-up page are invalid.
Some regression tests are added to check such scenarios, able to
reproduce the original problem. In the test, the contents of a
continuation record are overwritten with junk zeros on its follow-up
page, and replayed on standbys. This is inspired by 039_end_of_wal.pl,
and is enough to show how standbys should react on promotion by not
being stuck. Without the fix, the test would fail with a timeout. The
test to reproduce the problem has been written by Alexander Kukushkin.
The original check has been introduced in 0668719801, for a similar
problem.
Author: Kyotaro Horiguchi, Alexander Kukushkin
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/CAFh8B=mozC+e1wGJq0H=0O65goZju+6ab5AU7DEWCSUA2OtwDg@mail.gmail.com
Backpatch-through: 13
These have been #ifdef'd out for a long time, and in fact have
been uncompilable since commit 48354581a of 2016-04-10. The
fact that nobody noticed for so long demonstrates their lack of
usefulness, so let's remove them rather than fix them.
Author: Jacob Brazeal <jacob.brazeal@gmail.com>
Discussion: https://postgr.es/m/CA+COZaB+9CN_f63PPRoVhHjYmCwwmb_9CWLxqCJdMWDqs1a-JA@mail.gmail.com
The PG_UNICODE_FAST locale uses code point sort order (fast,
memcmp-based) combined with Unicode character semantics. The character
semantics are based on Unicode full case mapping.
Full case mapping can map a single codepoint to multiple codepoints,
such as "ß" uppercasing to "SS". Additionally, it handles
context-sensitive mappings like the "final sigma", and it uses
titlecase mappings such as "Dž" when titlecasing (rather than plain
uppercase mappings).
Importantly, the uppercasing of "ß" as "SS" is specifically mentioned
by the SQL standard. In Postgres, UCS_BASIC uses plain ASCII semantics
for case mapping and pattern matching, so if we changed it to use the
PG_UNICODE_FAST locale, it would offer better compliance with the
standard. For now, though, do not change the behavior of UCS_BASIC.
Discussion: https://postgr.es/m/ddfd67928818f138f51635712529bc5e1d25e4e7.camel@j-davis.com
Discussion: https://postgr.es/m/27bb0e52-801d-4f73-a0a4-02cfdd4a9ada@eisentraut.org
Reviewed-by: Peter Eisentraut, Daniel Verite
Given a qualified refname, refnameNamespaceItem() will search for a
matching namespace item by relation OID, rather than by name. Commit
80feb727c8 broke this by adding additional namespace items for OLD and
NEW in the RETURNING list, which have the same relation OID, causing
ambiguity. Fix this by ignoring these in the search, which is correct
since they don't match the qualified relation name, and so there is no
real ambiguity.
Reported by Richard Guo.
Discussion: https://postgr.es/m/CAMbWs49MBjWYWDROJ8MZ%3DY%2B4UgRQa10wzik1tWrD5yto9eoGXg%40mail.gmail.com
Previously, hex_encode looked up each nibble of the input
separately. We now use a larger lookup table containing the two-byte
encoding of every possible input byte, resulting in a 1/3 reduction
in encoding time.
Reviewed by Tom Lane, Michael Paquier, Nathan Bossart, David Rowley
Discussion: https://postgr.es/m/CANWCAZZvXuJMgqMN4u068Yqa19CEjS31tQKZp_qFFFbgYfaXqQ%40mail.gmail.com
Remove the flex version checks from configure and meson. The cutoff
versions are all so ancient that this is no longer relevant, and what
the actual cutoff should be is a bit fuzzy.
This also removes the ancient behavior that configure would also
accept a "lex" program if it is actuall flex. This aligns the check
with meson in this respect.
For future reference, as of this commit, these are relevant flex
versions:
- The hard required minimum is flex 2.5.34 as of commit b1ef48980d,
but this has not actually been tested.
- Prior to this, the minimum enforced by configure/meson was flex
2.5.35, which is the oldest present in the buildfarm right now.
- As of commit 6fdd5d9563, the oldest version that will compile
without warnings due to flex-generated code is flex 2.5.36.
- The oldest version that probably still has some practical relevance
is flex 2.5.37, which ships with CentOS/RHEL 7.
Discussion: https://www.postgresql.org/message-id/1a204ccd-7ae6-478c-a431-407b5c48ccc6@eisentraut.org
This commit reverts 8f67f994e8 (down to v13) and c3de0f9eed (down to
v17), as these are proving to not be completely correct regarding two
aspects:
- In v17 and newer branches, c3de0f9eed38's check for epoch handling is
incorrect, and does not correctly handle frozen epochs. A logic closer
to widen_snapshot_xid() should be used. The 2PC code should try to
integrate deeper with FullTransactionIds, 5a1dfde833 being not enough.
- In v13 and newer branches, 8f67f994e8 is a workaround for the real
issue, which is that we should not attempt CLOG lookups without reaching
consistency. This exists since 728bd991c3, and this is reachable with
ProcessTwoPhaseBuffer() called by restoreTwoPhaseData() at the beginning
of recovery.
Per discussion with Noah Misch.
Discussion: https://postgr.es/m/20250116010051.f3.nmisch@google.com
Backpatch-through: 13
We should run the expression subtrees of PartitionedRelPruneInfo
structs through fix_scan_expr. Failure to do so means that
AlternativeSubPlans within those expressions won't be cleaned up
properly, resulting in "unrecognized node type" errors since v14.
It seems fairly likely that at least some of the other steps done
by fix_scan_expr are important here as well, resulting in as-yet-
undetected bugs. Therefore, I've chosen to back-patch this to
all supported branches including v13, even though the known
symptom doesn't manifest in v13.
Per bug #18778 from Alexander Lakhin.
Discussion: https://postgr.es/m/18778-24cd399df6c806af@postgresql.org
Move the several members of HeapScanDescData which are specific to
Bitmap Heap Scans into a new struct, BitmapHeapScanDescData, which
inherits from HeapScanDescData.
This reduces the size of the HeapScanDescData for other types of scans
and will allow us to add additional bitmap heap scan-specific members in
the future without fear of bloating the HeapScanDescData.
Reviewed-by: Tomas Vondra
Discussion: https://postgr.es/m/c736f6aa-8b35-4e20-9621-62c7c82e2168%40vondra.me
As written, it was triggering a compilation warning for old versions of
clang, as reported by buildfarm members ayu, batfish and demoiselle.
Forcing a cast with "unsigned int" should fix the warning.
While on it, the macro is moved to pgstat.h, closer to the declaration
of IOOp, per suggestion from Tom Lane.
Reported-by: Tom Lane
Reviewed-by: Bertrand Drouvot, Tom Lane, Nazir Bilal Yavuz
Discussion: https://postgr.es/m/1272824.1736961543@sss.pgh.pa.us
If a time zone abbreviation used in datetime input is defined in
the currently active timezone, use that definition in preference
to looking in the timezone_abbreviations list. That allows us to
correctly handle abbreviations that have different meanings in
different timezones. Also, it eliminates an inconsistency between
datetime input and datetime output: the non-ISO datestyles for
timestamptz have always printed abbreviations taken from the IANA
data, not from timezone_abbreviations. Before this fix, it was
possible to demonstrate cases where casting a timestamp to text
and back fails or changes the value significantly because of that
inconsistency.
While this change removes the ability to override the IANA data about
an abbreviation known in the current zone, it's not clear that there's
any real use-case for doing so. But it is clear that this makes life
a lot easier for dealing with abbreviations that have conflicts across
different time zones.
Also update the pg_timezone_abbrevs view to report abbreviations
that are recognized via the IANA data, and *not* report any
timezone_abbreviations entries that are thereby overridden.
Under the hood, there are now two SRFs, one that pulls the IANA
data and one that pulls timezone_abbreviations entries. They're
combined by logic in the view. This approach was useful for
debugging (since the functions can be called on their own).
While I don't intend to document the functions explicitly,
they might be useful to call directly.
Also improve DecodeTimezoneAbbrev's caching logic so that it can
cache zone abbreviations found in the IANA data. Without that,
this patch would have caused a noticeable degradation of the
runtime of timestamptz_in.
Per report from Aleksander Alekseev and additional investigation.
Discussion: https://postgr.es/m/CAJ7c6TOATjJqvhnYsui0=CO5XFMF4dvTGH+skzB--jNhqSQu5g@mail.gmail.com
With this, we have separate functions to add validation requests to
ALTER TABLE's phase 3 queue for check and foreign key constraints, which
allows reusing them in future commits -- particularly this will allow us
to perform validation of invalid foreign key constraints in partitioned
tables.
We could have let the check constraint code alone since we don't need to
reuse that for anything at this point, but it seems cleaner and more
consistent to do both at the same time.
Author: Amul Sul <sulamul@gmail.com>
Discussion: https://postgr.es/m/CAAJ_b96Bp=-ZwihPPtuaNX=SrZ0U6ZsXD3+fgARO0JuKa8v2jQ@mail.gmail.com
This allows the RETURNING list of INSERT/UPDATE/DELETE/MERGE queries
to explicitly return old and new values by using the special aliases
"old" and "new", which are automatically added to the query (if not
already defined) while parsing its RETURNING list, allowing things
like:
RETURNING old.colname, new.colname, ...
RETURNING old.*, new.*
Additionally, a new syntax is supported, allowing the names "old" and
"new" to be changed to user-supplied alias names, e.g.:
RETURNING WITH (OLD AS o, NEW AS n) o.colname, n.colname, ...
This is useful when the names "old" and "new" are already defined,
such as inside trigger functions, allowing backwards compatibility to
be maintained -- the interpretation of any existing queries that
happen to already refer to relations called "old" or "new", or use
those as aliases for other relations, is not changed.
For an INSERT, old values will generally be NULL, and for a DELETE,
new values will generally be NULL, but that may change for an INSERT
with an ON CONFLICT ... DO UPDATE clause, or if a query rewrite rule
changes the command type. Therefore, we put no restrictions on the use
of old and new in any DML queries.
Dean Rasheed, reviewed by Jian He and Jeff Davis.
Discussion: https://postgr.es/m/CAEZATCWx0J0-v=Qjc6gXzR=KtsdvAE7Ow=D=mu50AgOe+pvisQ@mail.gmail.com
This splits out a couple of subroutines from
ATExecAlterConstrRecurse(). This makes the main function a bit
smaller, and a future patch (NOT ENFORCED foreign-key constraints)
will also want to call some of the pieces separately.
Author: Amul Sul <amul.sul@enterprisedb.com>
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAAJ_b962c5AcYW9KUt_R_ER5qs3fUGbe4az-SP-vuwPS-w-AGA%40mail.gmail.com
Add more comments at the top of vacuumlazy.c on heap relation vacuuming
implementation.
Previously vacuumlazy.c only had details related to dead TID storage.
This commit adds a more general summary to help future developers
understand the heap relation vacuum design and implementation at a high
level.
Reviewed-by: Alena Rybakina, Robert Haas, Andres Freund, Bilal Yavuz
Discussion: https://postgr.es/m/flat/CAAKRu_ZF_KCzZuOrPrOqjGVe8iRVWEAJSpzMgRQs%3D5-v84cXUg%40mail.gmail.com
This enables SCRAM authentication for postgres_fdw when connecting to
a foreign server without having to store a plain-text password on user
mapping options.
This is done by saving the SCRAM ClientKey and ServeryKey from the
client authentication and using those instead of the plain-text
password for the server-side SCRAM exchange. The new foreign-server
or user-mapping option "use_scram_passthrough" enables this.
Co-authored-by: Matheus Alcantara <mths.dev@pm.me>
Co-authored-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://www.postgresql.org/message-id/flat/27b29a35-9b96-46a9-bc1a-914140869dac@gmail.com
The "does not exist" error in object_aclmask_ext() was written as
ereport(), suggesting that it is user-facing. This is problematic:
get_object_class_descr() is meant to be for internal errors only and
does not support translation.
For the has_xxx_privilege functions, the error has not been
user-facing since commit 403ac226dd. The remaining users are
pg_database_size() and pg_tablespace_size(). The call stack here is
pretty deep and this dependency is not obvious. Here we can put in an
explicit existence check with a bespoke error message early in the
function.
Then we can downgrade the error in object_aclmask_ext() to a normal
"cache lookup failed" internal error.
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://www.postgresql.org/message-id/flat/da2f8942-be6d-48d0-ac1c-a053370a6b1f@eisentraut.org
The "does not exist" errors in object_ownership() were written as
ereport(), suggesting that they are user-facing. But no code path
except one can reach this function without first checking that the
object exists. If this were actually a user-facing error message,
then there would be some problems: get_object_class_descr() is meant
to be for internal errors only and does not support translation.
The one case that can reach this without first checking the object
existence is from be_lo_unlink(). (This makes some sense since large
objects are referred to by their OID directly.) In this one case, we
can add a line of code to check the object existence explicitly,
consistent with other LO code.
For the rest, downgrade the error messages to elog()s. The new
message wordings are the same as in DropObjectById().
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://www.postgresql.org/message-id/flat/da2f8942-be6d-48d0-ac1c-a053370a6b1f@eisentraut.org
This removes all the various workarounds for avoiding compiler
warnings with Flex 2.5.35. Several recent patches have added
additional warnings that would either need to be fixed along the lines
of the existing workarounds, or we decide to no longer care about
this, which we do here.
Flex 2.5.35 is extremely outdated, and you can't even download it
anymore from any of the Flex project sites, so it's nearly impossible
to support.
After this, using Flex 2.5.35 will still work, but the generated code
will produce numerous compiler warnings.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/1a204ccd-7ae6-478c-a431-407b5c48ccc6@eisentraut.org
This changes commit 7406ab623f in that the gist strategy number
mapping support function is changed to use the CompareType enum as
input, instead of the "well-known" RT*StrategyNumber strategy numbers.
This is a bit cleaner, since you are not dealing with two sets of
strategy numbers. Also, this will enable us to subsume this system
into a more general system of using CompareType to define operator
semantics across index methods.
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
RowCompareType served as a way to describe the fundamental meaning of
an operator, notionally independent of an operator class (although so
far this was only really supported for btrees). Its original purpose
was for use inside RowCompareExpr, and it has also found some small
use outside, such as for get_op_btree_interpretation().
We want to expand this now, as a more general way to describe operator
semantics for other index access methods, including gist (to improve
GistTranslateStratnum()) and others not written yet. To avoid future
confusion, we rename the type to CompareType and the symbols from
ROWCOMPARE_XXX to COMPARE_XXX to reflect their more general purpose.
Reviewed-by: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
ca9c6a5680 consolidated most of the vacuum-related GUCs' documentation
into a new subsection. af2317652d then enforced this order in
postgresql.conf.sample. This commit reorganizes the GUC groups in
guc_tables.c/h to match the updated ordering in the docs.
Reported-by: Álvaro Herrera
Reviewed-by: Álvaro Herrera, Alena Rybakina
Discussion: https://postgr.es/m/202501132046.m4mcvxxswznu%40alvherre.pgsql
If a new catalog tuple is inserted that belongs to a catcache list
entry, and cache invalidation happens while the list entry is being
built, the list entry might miss the newly inserted tuple.
To fix, change the way we detect concurrent invalidations while a
catcache entry is being built. Keep a stack of entries that are being
built, and apply cache invalidation to those entries in addition to
the real catcache entries. This is similar to the in-progress list in
relcache.c.
Back-patch to all supported versions.
Reviewed-by: Noah Misch
Discussion: https://www.postgresql.org/message-id/2234dc98-06fe-42ed-b5db-ac17384dc880@iki.fi
This function expects an "int64" as result and stores the number of
pages to add to the index scan bitmap as an "int", multiplying its final
result by 10. For a relation large enough, this can theoretically
overflow if counting more than (INT32_MAX / 10) pages, knowing that the
number of pages is upper-bounded by MaxBlockNumber.
To avoid the overflow, this commit redefines "totalpages", used to
calculate the result, to be an "int64" rather than an "int".
Reported-by: Evgeniy Gorbanyov
Author: James Hunter
Discussion: https://www.postgresql.org/message-id/07704817-6fa0-460c-b1cf-cd18f7647041@basealt.ru
Backpatch-through: 13
Currently in pg_stat_io view, IOs are counted as blocks of size
BLCKSZ. There are two limitations with this design:
* The actual number of I/O requests sent to the kernel is lower because
I/O requests may be merged before being sent. Additionally, it gives
the impression that all I/Os are done in block size, which shadows the
benefits of merging I/O requests.
* Some patches are under work to extend pg_stat_io for the tracking of
operations that may not be linked to the block size. For example, WAL
read IOs are done in variable bytes and it is not possible to correctly
show these IOs in pg_stat_io view, and we want to keep all this data in
a single system view rather than spread it across multiple relations to
ease monitoring.
WaitReadBuffers() can now be tracked as a single read operation
worth N blocks. Same for ExtendBufferedRelShared() and
ExtendBufferedRelLocal() for extensions.
Three columns are added to pg_stat_io for reads, writes and extensions
for the byte calculations. op_bytes, which was always hardcoded to
BLCKSZ, is removed. IO backend statistics are updated to reflect these
changes.
Bump catalog version.
Author: Nazir Bilal Yavuz
Reviewed-by: Bertrand Drouvot, Melanie Plageman
Discussion: https://postgr.es/m/CAN55FZ0oqxBaaHAEsj=xFqkzE3n5P=3RA1V_igXwL-RV7QRzyw@mail.gmail.com
ca9c6a5680 consolidated most of vacuum-related GUCs' documentation into
a new subsection. It neglected, however, to reorganize
postgresql.conf.sample to match the new order. Do this now.
Reported-by: Álvaro Herrera
Discussion: https://postgr.es/m/202501110902.5banlseavz7c%40alvherre.pgsql
Commit 27a1f8d108 missed updating the max HBA option count to
account for the new option added. Fix by bumping the counter
and adjust the relevant comment to match. Backpatch down to
all supported branches like the erroneous commit.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/286764.1736697356@sss.pgh.pa.us
Backpatch-through: v13
When deparsing a JsonExpr, variable names in the PASSING clause were
not quoted. However, since they are parsed as ColLabel tokens, some
variable names require double quotes to ensure that they are properly
interpreted. Fix by using quote_identifier() in the deparsing code.
This oversight was limited to the SQL/JSON query functions
JSON_EXISTS(), JSON_QUERY(), and JSON_VALUE().
Back-patch to v17, where these functions were added.
Dean Rasheed, reviewed by Tom Lane.
Discussion: https://postgr.es/m/CAEZATCXTpAS%3DncfLNTZ7YS6O5puHeLg_SUYAit%2Bcs7wsrd9Msg%40mail.gmail.com
When deparsing an XMLTABLE() expression, XML namespace names were not
quoted. However, since they are parsed as ColLabel tokens, some names
require double quotes to ensure that they are properly interpreted.
Fix by using quote_identifier() in the deparsing code.
Back-patch to all supported versions.
Dean Rasheed, reviewed by Tom Lane.
Discussion: https://postgr.es/m/CAEZATCXTpAS%3DncfLNTZ7YS6O5puHeLg_SUYAit%2Bcs7wsrd9Msg%40mail.gmail.com
This adds support for the NOT ENFORCED/ENFORCED flag for constraints,
with support for check constraints.
The plan is to eventually support this for foreign key constraints,
where it is typically more useful.
Note that CHECK constraints do not currently support ALTER operations,
so changing the enforceability of an existing constraint isn't
possible without dropping and recreating it. This could be added
later.
Author: Amul Sul <amul.sul@enterprisedb.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: jian he <jian.universality@gmail.com>
Tested-by: Triveni N <triveni.n@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/CAAJ_b962c5AcYW9KUt_R_ER5qs3fUGbe4az-SP-vuwPS-w-AGA@mail.gmail.com
Previously, the caller needed to allocate the memory and the
TupleHashTable would store a pointer to it. That wastes space for the
palloc overhead as well as the size of the pointer itself.
Now, the TupleHashTable relies on the caller to correctly specify the
additionalsize, and allocates that amount of space. The caller can
then request a pointer into that space.
Discussion: https://postgr.es/m/b9cbf0219a9859dc8d240311643ff4362fd9602c.camel@j-davis.com
Reviewed-by: Heikki Linnakangas
6f3820f37 adjusted the assert-enabled validation of the CompactAttribute
to call a new external function to perform the validation. That commit
made it so the function was only available when building with
USE_ASSERT_CHECKING, and because TupleDescCompactAttr() is a static
inline function, the call to verify_compact_attribute() was compiled
into any extension which uses TupleDescCompactAttr(). This caused issues
for such extensions when loading the assert-enabled extension into
PostgreSQL versions without asserts enabled due to that function being
unavailable in core.
To fix this, make verify_compact_attribute() available unconditionally,
but make it do nothing unless building with USE_ASSERT_CHECKING.
Author: Andrew Kane <andrew@ankane.org>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAOdR5yHfMEMW00XGo=v1zCVUS6Huq2UehXdvKnwtXPTcZwXhmg@mail.gmail.com
The ldapscheme option was missed when inspecing the HbaLine for
assembling rows for the pg_hba_file_rules function. Backpatch
to all supported versions.
Author: Laurenz Albe <laurenz.albe@cybertec.at>
Reported-by: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Bug: 18769
Discussion: https://postgr.es/m/18769-dd8610cbc0405172@postgresql.org
Backpatch-through: v13
Oversight in commit 1bd4bc85, which made nbtree backwards scans operate
off of a copy of each page's left link as of the time of its call to
_bt_readpage.
The previous names weren't particularly clear. Future patches will add more
shutdown phases, making it even more important to have understandable shutdown
phases.
Suggested-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/d2cd8fd3-396a-4390-8f0b-74be65e72899@iki.fi
Previously many, in some cases important, signals we never logged. In other
cases the signal name was only included numerically.
As part of this, change the debug log level the signal is logged at to DEBUG3,
previously some where DEBUG2, some DEBUG4.
Also move from direct use of kill() to signal the av launcher to
signal_child(). There doesn't seem to be a reason for directly using kill().
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/kgng5nrvnlv335evmsuvpnh354rw7qyazl73kdysev2cr2v5zu@m3cfzxicm5kp
This makes logging of state changes easier - state transitions are now logged
at DEBUG1. Without that logging it was surprisingly hard to understand the
current state of the system while debugging.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/kgng5nrvnlv335evmsuvpnh354rw7qyazl73kdysev2cr2v5zu@m3cfzxicm5kp
cluster_rel() receives the OID of the relation to process, which it
opens and locks; but then its subroutine copy_table_data() also receives
the relation OID and opens it by itself. This is a bit wasteful. It's
better to have cluster_rel() receive the relation already open, and pass
it down to its subroutines as necessary; then cluster_rel closes the rel
before returning. This simplifies things.
But a better motivation to make this change is that a future command to
do logical-decoding-based "concurrent VACUUM FULL" will need to release
all locks on the relation (and possibly on the clustering index) at some
point. Since it makes little sense to keep the relation reference
without the lock, the cluster_rel() function will also close it (and
the index). With this arrangement, neither the function nor its
subroutines need open extra references, which, again, makes things simpler.
Author: Antonin Houska <ah@cybertec.at>
Discussion: https://postgr.es/m/82651.1720540558@antos
66c0185a3 gave the planner the ability to have union child queries
provide the union planner with pre-sorted input so that UNION queries
could be more efficiently implemented using Merge Append.
That commit overlooked checking that the UNION target list and the union
child target list's types all match. In some corner cases, this could
result in the planner producing sorts using the sort operator of the
top-level UNION's target list type rather than of the union child's
target list's type. The implications of this range from silently
working correctly, despite using the wrong sort operator all the way up
to a segmentation fault.
Here we fix by adjusting the planner so it makes no attempt to have the
subquery produce pre-sorted results when the data type of the UNION
target list and the types from the subquery target list don't match
exactly.
Backpatch to 17, where 66c0185a3 was introduced.
Reported-by: Jason Smith <dqetool@126.com>
Diagnosed-by: Tom Lane <tgl@sss.pgh.pa.us>
Bug: 18764
Discussion: https://postgr.es/m/18764-63ad667ea26e877a%40postgresql.org
Backpatch-through: 17
The pgstat_count_io_op() function, which counts a single I/O operation,
wraps pgstat_count_io_op_n() with a counter value of 1. The latter is
declared in pgstat.h and used nowhere in the code, so let's remove it in
favor of the former.
This change makes also the code more symmetric with
pgstat_count_io_op_time(), that already uses a similar set of arguments,
except that it counts also the I/O time. This will ease a bit the
integration of a follow-up patch that adds byte-level tracking in
pg_stat_io for some of its attributes, lifting the current restriction
based on BLCKSZ as all I/O operations are assumed to be block-based.
Author: Nazir Bilal Yavuz
Reviewed-by: Bertrand Drouvot
Discussion: https://postgr.es/m/CAN55FZ32ze812=yjyZg1QeXhKvACUM_Nu0_gyPQcUKKuVHL5xA@mail.gmail.com
This commit changes the way pending backend statistics are tracked by
moving them into a new structure called PgStat_BackendPending, removing
PgStat_BackendPendingIO. PgStat_BackendPending currently only includes
PgStat_PendingIO for the pending I/O stats.
pgstat_flush_backend() is extended with a "flags" argument to control
which parts of the stats of a backend should be flushed.
With this refactoring, it becomes easier to plug into backend statistics
more data. A patch to add information related to WAL in this stats kind
is under discussion.
Author: Bertrand Drouvot
Discussion: https://postgr.es/m/Z3zqc4o09dM/Ezyz@ip-10-97-1-34.eu-west-3.compute.internal
This error message stated the privileges required to add a member
to a group even if the user was trying to drop a member:
postgres=> alter group a drop user b;
ERROR: permission denied to alter role
DETAIL: Only roles with the ADMIN option on role "a" may add members.
Since the required privileges for both operations are the same, we
can fix this by modifying the message to mention both adding and
dropping members:
postgres=> alter group a drop user b;
ERROR: permission denied to alter role
DETAIL: Only roles with the ADMIN option on role "a" may add or drop members.
Author: ChangAo Chen
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/tencent_FAA0D00E3514AAF0BBB6322542A6094FEF05%40qq.com
Backpatch-through: 16
This function doesn't need the lockmode to be passed: it was being used
to lock the new heap, but that's bogus, because the only caller has
already obtained the appropriate lock on the new heap (which is
unimportant anyway, because the relation's creation is not yet committed
and so no other session can see it).
Noticed while reviewed Antonin Houska's patch to add VACUUM FULL
CONCURRENTLY.
The originally submitted code (using bit masking) was correct when the
number of slots was restricted to be a power of two -- but that
limitation was removed during development that led to commit
53c2a97a92, which made the bank selection code incorrect. This led to
always using a smaller number of banks than available. Change said code
to use integer modulo instead, which works correctly with an arbitrary
number of banks.
It's likely that we could improve on this to avoid runtime use of
integer division. But with this change we're, at least, not wasting
memory on unused banks, and more banks mean less contention, which is
likely to have a much higher performance impact than a single
instruction's latency.
Author: Yura Sokolov <y.sokolov@postgrespro.ru>
Reviewed-by: Andrey Borodin <x4mmm@yandex-team.ru>
Discussion: https://postgr.es/m/9444dc46-ca47-43ed-9058-89c456316306@postgrespro.ru
A named tuplestore is necessarily a transient object, so it makes
no sense to reference one in a persistent object such as a view.
We didn't previously prevent that, with the result that if you
tried you would get some weird failure about how the executor
couldn't find the tuplestore.
We can mechanize a check for this case cheaply by making dependency
extraction complain if it comes across such an RTE. This is a
plausible way of dealing with it since part of the problem is that we
have no way to make a pg_depend representation of a named tuplestore.
Report and fix by Yugo Nagata. Although this is an old problem,
it's a very weird corner case and there have been no reports from
end users. So it seems sufficient to fix it in master.
Discussion: https://postgr.es/m/20240726160714.e74d0db579f2c017e1ca0b7e@sraoss.co.jp
Commit 14e87ffa5c needlessly added support for CONSTR_NOTNULL entries
to StoreConstraints. It's dead code, so remove it.
To make the situation regarding constraint creation clearer, change
comments in heap_create_with_catalog, StoreConstraints, MergeAttributes
to explain which types of constraint are used on each.
Author: 何建 (Jian He) <jian.universality@gmail.com>
Discussion: https://postgr.es/m/CACJufxFxzqrCiUNfjJ0tQU+=nKQkQCGtGzUBude=SMOwj5VNjQ@mail.gmail.com
Move nbtree's detection of RowCompare quals that are unsatisfiable due
to having a NULL in their first row element: rather than detecting these
cases at the point where _bt_first builds its insertion scan key, do so
earlier, during preprocessing proper. This brings the RowCompare case
in line every other case involving an unsatisfiable-due-to-NULL qual.
nbtree now consistently detects such unsatisfiable quals -- even when
they happen to involve a key that isn't examined by _bt_first at all.
Affected cases thereby avoid useless full index scans that cannot
possibly return any matching rows.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/CAH2-WzmySVXst2hFrOATC-zw1Byg1XC-jYUS314=mzuqsNwk+Q@mail.gmail.com
This new structure relieves _bt_first from having separate calls to
_bt_start_array_keys for the serial case and parallel case. This saves
code, and seems clearer.
Follow-up to work from commits 4e6e375b and b5ee4e52.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/CAH2-Wz=XjUZjBjHJdhTvuH5MwoJObWGoM2RG2LyFg5WUdWyk=A@mail.gmail.com
The parameter 'rel' in lookup_var_attr_stats was once used to draw an
ERROR when ANALYZE failed to acquire sufficient data to build extended
statistics. bf2a691e0 changed the logic to raise a WARNING in the
caller instead. As a result, this parameter is no longer needed and
can be removed. Since this is a static function, we can always easily
reintroduce the parameter if it's ever needed in the future.
Author: Ilia Evdokimov
Reviewed-by: Fabrízio de Royes Mello
Discussion: https://postgr.es/m/b3880f22-5808-4206-88d4-1553a81c3440@tantorlabs.com
This commit introduces a new parameter named
autovacuum_worker_slots that controls how many autovacuum worker
slots to reserve during server startup. Modifying this new
parameter's value does require a server restart, but it should
typically be set to the upper bound of what you might realistically
need to set autovacuum_max_workers. With that new parameter in
place, autovacuum_max_workers can now be changed with a SIGHUP
(e.g., pg_ctl reload).
If autovacuum_max_workers is set higher than
autovacuum_worker_slots, a WARNING is emitted, and the server will
only start up to autovacuum_worker_slots workers at a given time.
If autovacuum_max_workers is set to a value less than the number of
currently-running autovacuum workers, the existing workers will
continue running, but no new workers will be started until the
number of running autovacuum workers drops below
autovacuum_max_workers.
Reviewed-by: Sami Imseih, Justin Pryzby, Robert Haas, Andres Freund, Yogesh Sharma
Discussion: https://postgr.es/m/20240410212344.GA1824549%40nathanxps13
Previously, this was notionally used only for the entry point of the
tree and as a convenient parent for other contexts.
For shared memory, the creator previously allocated the entry point
in this context, but attaching backends didn't have access to that,
so they just used the caller's context. For the sake of consistency,
allocate every instance of an entry point in the caller's context.
For local memory, allocate the control object in the caller's context
as well. This commit also makes the "leaf context" the notional parent
of the child contexts used for nodes, so it's a bit of a misnomer,
but a future commit will make the node contexts independent rather
than children, so leave it this way for now to avoid code churn.
The memory context parameter for RT_CREATE is now unused in the case
of shared memory, so remove it and adjust callers to match.
In passing, remove unused "context" member from struct TidStore,
which seems to have been an oversight.
Reviewed by Masahiko Sawada
Discussion: https://postgr.es/m/CANWCAZZDCo4k5oURg_pPxM6+WZ1oiG=sqgjmQiELuyP0Vtrwig@mail.gmail.com
Slightly faulty logic in the original jsonb code (commit d9134d0a35)
results in an empty top level array sorting less than a json null. We
can't change the sort order now since it would affect btree indexes over
jsonb, so document the anomaly.
Backpatch to all live branches (13 .. 17)
In master, also add a code comment noting the anomaly.
Reported-by: Yan Chengpen
Reviewed-by: Jian He
Discussion: https://postgr.es/m/OSBPR01MB45199DD8DA2D1CECD50518188E272@OSBPR01MB4519.jpnprd01.prod.outlook.com
When looking up statistical data about an expression, we do not need
to concern ourselves with the outer joins that could null the
Vars/PHVs contained in the expression. Accounting for nullingrels in
the expression could cause estimate_num_groups to count the same Var
multiple times if it's marked with different nullingrels. This is
incorrect, and could lead to "ERROR: corrupt MVNDistinct entry" when
searching for multivariate n-distinct.
Furthermore, the nullingrels could prevent us from matching an
expression to expressional index columns or to the expressions in
extended statistics, leading to inaccurate estimates.
To fix, strip out all the nullingrels from the expression before we
look up statistical data about it. There is one ensuing plan change
in the regression tests, but it looks reasonable and does not
compromise its original purpose.
This patch could result in plan changes, but it fixes an actual bug,
so back-patch to v16 where the outer-join-aware-Var infrastructure was
introduced.
Author: Richard Guo
Discussion: https://postgr.es/m/CAMbWs4-2Z4k+nFTiZe0Qbu5n8juUWenDAtMzi98bAZQtwHx0-w@mail.gmail.com
CHUNKHDRSZ was defined as 16 bytes, which was true when that code went in,
but since c6e0fe1f2, 8 is a more accurate value. Here we adjust it to use
sizeof(MemoryChunk), which is normally 8, or 16 for cassert builds.
c6e0fe1f2 first appeared in v16, so this is technically wrong in v16 up
to master, but let's apply this only to master as adjusting this does
influence the estimated number of batches in the aggregate costing code
and we don't want to cause plan instability in released versions.
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/CAApHDvpMpRQvsTqZo3FinXkgytwxwF8sCyZm83xDj-1s_hLe+w@mail.gmail.com
pgoutput caches the attribute map of a relation, that is free()'d only
when validating a RelationSyncEntry. However, this code path is not
taken when calling any of the SQL functions able to do some logical
decoding, like pg_logical_slot_{get,peek}_changes(), leaking some memory
into CacheMemoryContext on repeated calls.
To address this, a relation's attribute map is allocated in
PGOutputData's cachectx, free()'d at the end of the execution of these
SQL functions when logical decoding ends. This is available down to 15.
v13 and v14 have a similar leak, which will be dealt with later.
Reported-by: Masahiko Sawada
Author: Vignesh C
Reviewed-by: Hou Zhijie
Discussion: https://postgr.es/m/CAD21AoDkAhQVSukOfH3_reuF-j4EU0-HxMqU3dU+bSTxsqT14Q@mail.gmail.com
Discussion: https://postgr.es/m/CALDaNm1hewNAsZ_e6FF52a=9drmkRJxtEPrzCB6-9mkJyeBBqA@mail.gmail.com
Backpatch-through: 15
At the beginning of recovery, an orphaned two-phase file in an epoch
different than the one defined in the checkpoint record could not be
removed based on the assumptions that AdjustToFullTransactionId() relies
on, assuming that all files would be either from the current epoch or
from the previous epoch.
If the checkpoint epoch was 0 while the 2PC file was orphaned and in the
future, AdjustToFullTransactionId() would underflow the epoch used to
build the 2PC file path. In non-assert builds, this would create a
WARNING message referring to a 2PC file with an epoch of "FFFFFFFF" (or
UINT32_MAX), as an effect of the underflow calculation, leaving the
orphaned file around.
Some tests are added with dummy 2PC files in the past and the future,
checking that these are properly removed.
Issue introduced by 5a1dfde833, that has switched two-phase state
files to use FullTransactionIds.
Reported-by: Vitaly Davydov
Author: Michael Paquier
Reviewed-by: Vitaly Davydov
Discussion: https://postgr.es/m/13b5b6-676c3080-4d-531db900@47931709
Backpatch-through: 17
Before 728bd991c3, that has improved the support for 2PC files during
recovery, the initial logic scanning files in pg_twophase was done so as
files in the future of the transaction ID horizon were checked first,
followed by a check if a transaction ID is aborted or committed which
could involve a pg_xact lookup. After this commit, these checks have
been done in reverse order.
Files detected as in the future do not have a state that can be checked
in pg_xact, hence this caused recovery to fail abruptly should an
orphaned 2PC file in the future of the transaction ID horizon exist in
pg_twophase at the beginning of recovery.
A test is added to check for this scenario, using an empty 2PC with a
transaction ID large enough to be in the future when running the test.
This test is added in 16 and older versions for now. 17 and newer
versions are impacted by a second bug caused by the addition of the
epoch in the 2PC file names. An equivalent test will be added in these
branches in a follow-up commit, once the second set of issues reported
are fixed.
Author: Vitaly Davydov, Michael Paquier
Discussion: https://postgr.es/m/11e597-676ab680-8d-374f23c0@145466129
Backpatch-through: 13
These arrays were sized with Natts_pg_trigger (19) when they should have
been sized with Natts_pg_event_trigger (7). We'd better fix this as
it's clearly a mistake and it could become problematic if
pg_event_trigger were to gain a dozen or so more columns in the future.
No backpatch as there's no actual bug and the column count on those
tables isn't going to change in released versions.
Author: Xin Zhang <zhanghien@qq.com>
Discussion: https://postgr.es/m/tencent_05AD0FB321A414EC3661204D2102AA6EF605@qq.com
Commit 34486b609 effectively redefined isBackgroundWorker as meaning
"not a regular backend", whereas before it had the narrower
meaning of AmBackgroundWorkerProcess(). For clarity, rename the
field to isRegularBackend and invert its sense.
Discussion: https://postgr.es/m/1808397.1735156190@sss.pgh.pa.us
Cause parallel workers to not check datallowconn, rolcanlogin, and
ACL_CONNECT privileges. The leader already checked these things
(except for rolcanlogin which might have been checked for a different
role). Re-checking can accomplish little except to induce unexpected
failures in applications that might not even be aware that their query
has been parallelized. We already had the principle that parallel
workers rely on their leader to pass a valid set of authorization
information, so this change just extends that a bit further.
Also, modify the ReservedConnections, datconnlimit and rolconnlimit
logic so that these limits are only enforced against regular backends,
and only regular backends are counted while checking if the limits
were already reached. Previously, background processes that had an
assigned database or role were subject to these limits (with rather
random exclusions for autovac workers and walsenders), and the set of
existing processes that counted against each limit was quite haphazard
as well. The point of these limits, AFAICS, is to ensure the
availability of PGPROC slots for regular backends. Since all other
types of processes have their own separate pools of PGPROC slots, it
makes no sense either to enforce these limits against them or to count
them while enforcing the limit.
While edge-case failures of these sorts have been possible for a
long time, the problem got a good deal worse with commit 5a2fed911
(CVE-2024-10978), which caused parallel workers to make some of these
checks using the leader's current role where before we had used its
AuthenticatedUserId, thus allowing parallel queries to fail after
SET ROLE. The previous behavior was fairly accidental and I have
no desire to return to it.
This patch includes reverting 73c9f91a1, which was an emergency hack
to suppress these same checks in some cases. It wasn't complete,
as shown by a recent bug report from Laurenz Albe. We can also revert
fd4d93d26 and 492217301, which hacked around the same problems in one
regression test.
In passing, remove the special case for autovac workers in
CheckMyDatabase; it seems cleaner to have AutoVacWorkerMain pass
the INIT_PG_OVERRIDE_ALLOW_CONNS flag, now that that does what's
needed.
Like 5a2fed911, back-patch to supported branches (which sadly no
longer includes v12).
Discussion: https://postgr.es/m/1808397.1735156190@sss.pgh.pa.us
The need for this was missed in commit 93db6cbda, with the result
being that if we launch a slotsync worker it would consume one of
the PGPROCs in the max_connections pool. That could lead to inability
to launch the worker, or to subsequent failures of connection requests
that should have succeeded according to the configured settings.
Rather than create some one-off infrastructure to support this,
let's group the slotsync worker with the existing autovac launcher
in a new category of "special worker" processes. These are kind of
like auxiliary processes, but they cannot use that infrastructure
because they need to be able to run transactions.
For the moment, make these processes share the PGPROC freelist
used for autovac workers (which previously supplied the autovac
launcher too). This is partly to avoid an ABI change in v17,
and partly because it seems silly to have a freelist with
at most two members. This might be worth revisiting if we grow
enough workers in this category.
Tom Lane and Hou Zhijie. Back-patch to v17.
Discussion: https://postgr.es/m/1808397.1735156190@sss.pgh.pa.us
Commit aac2c9b4fd mandated such locking
and attempted to fulfill that mandate, but it missed REASSIGN OWNED.
Hence, it remained possible to lose VACUUM's inplace update of
datfrozenxid if a REASSIGN OWNED processed that database at the same
time. This didn't affect the other inplace-updated catalog, pg_class.
For pg_class, REASSIGN OWNED calls ATExecChangeOwner() instead of the
generic AlterObjectOwner_internal(), and ATExecChangeOwner() fulfills
the locking mandate.
Like in GRANT, implement this by following the locking protocol for any
catalog subject to the generic AlterObjectOwner_internal(). It would
suffice to do this for IsInplaceUpdateOid() catalogs only. Back-patch
to v13 (all supported versions).
Kirill Reshke. Reported by Alexander Kukushkin.
Discussion: https://postgr.es/m/CAFh8B=mpKjAy4Cuun-HP-f_vRzh2HSvYFG3rhVfYbfEBUhBAGg@mail.gmail.com
This adjusts slot_deform_heap_tuple() to add special-case loops to
eliminate much of the branching that was done within the body of the
main deform loop.
Previously, while looping over each attribute to deform,
slot_deform_heap_tuple() would always recheck if the given attribute was
NULL by looking at HeapTupleHasNulls() and if so, went on to check the
tuple's NULL bitmap. Since many tuples won't contain any NULLs, we can
just check HeapTupleHasNulls() once and when there are no NULLs, use a
more compact version of the deforming loop which contains no NULL checking
code at all.
The same is possible for the "slow" mode checking part of the loop. That
variable was checked several times for each attribute, once to determine
if the offset to the attribute value could be taken from the attcacheoff,
and again to check if the offset could be cached for next time.
These "slow" checks can mostly be eliminated by instead having multiple
loops. Initially, we can start in the non-slow loop and break out of
that loop if and only if we must stop caching the offset. This
eliminates branching for both slow and non-slow deforming methods. The
amount of code required for the no nulls / non-slow version is very
small. It's possible to have separate loops like this due to the fact
that once we move into slow mode, we never need to switch back into
non-slow mode for a given tuple.
We have the compiler take care of writing out the multiple required
loops by having a pg_attribute_always_inline function which gets called
various times passing in constant values for the "slow" and "hasnulls"
parameters. This allows the compiler to eliminate const-false branches
and remove comparisons for const-true ones.
This commit has shown overall query performance increases of around 5-20%
in deform-heavy OLAP-type workloads.
Author: David Rowley
Reviewed-by: Victor Yegorov
Discussion: https://postgr.es/m/CAGnEbog92Og2CpC2S8=g_HozGsWtt_3kRS1sXjLz0jKSoCNfLw@mail.gmail.com
Discussion: https://postgr.es/m/CAApHDvo9e0XG71WrefYaRv5n4xNPLK4k8LjD0mSR3c9KR2vi2Q@mail.gmail.com
Previously, if an infinite value was passed to date_trunc(), then the
same infinite value would always be returned regardless of the field
unit given by the caller. This commit updates the function so that an
error is returned when an invalid unit is passed to date_trunc() with an
infinite value.
This matches the behavior of date_trunc() with a finite value and
date_part() with an infinite value, making the handling of interval,
timestamp and timestamptz more consistent across the board for these two
functions.
Some tests are added to cover all these new failure cases, with an
unsupported unit and infinite values for the three data types. There
were no test cases in core that checked all these patterns up to now.
Author: Joseph Koshakow
Discussion: https://postgr.es/m/CAAvxfHc4084dGzEJR0_pBZkDuqbPGc5wn7gK_M0XR_kRiCdUJQ@mail.gmail.com
The totalrows parameter in compute_expr_stats is unused, so remove it.
This is a static function, so the parameter can easily be added again if
it's ever needed.
Author: Ilia Evdokimov <ilya.evdokimov@tantorlabs.ru>
Discussion: https://postgr.es/m/667b92d2-f953-4fcb-9377-3765f5b94187@tantorlabs.com
Trying to clean up the code a bit while we're working on these files
for the reentrant scanner/pure parser patches. This cleanup only
touches the code sections after the second '%%' in each file, via a
manually-supervised and locally hacked up pgindent.
Use the flex %option reentrant to make the generated scanner
reentrant and thread-safe. Note: The parser was already pure.
Simplify flex scan buffer management: Instead of constructing the
buffer from pieces and then using yy_scan_buffer(), we can just use
yy_scan_string(), which does the same thing internally. (Actually, we
use yy_scan_bytes() here because we already have the length.)
Use flex yyextra to handle context information, instead of global
variables. This complements the other changes to make the scanner
reentrant.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Andreas Karlsson <andreas@proxel.se>
Discussion: https://www.postgresql.org/message-id/flat/eb6faeac-2a8a-4b69-9189-c33c520e5b7b@eisentraut.org
Use the flex %option reentrant and the bison option %pure-parser to
make the generated scanner and parser pure, reentrant, and
thread-safe.
Make the generated scanner use palloc() etc. instead of malloc() etc.
Previously, we only used palloc() for the buffer, but flex would still
use malloc() for its internal structures. Now, all the memory is
under palloc() control.
Simplify flex scan buffer management: Instead of constructing the
buffer from pieces and then using yy_scan_buffer(), we can just use
yy_scan_string(), which does the same thing internally.
The previous code was necessary because we allocated the buffer with
palloc() and the rest of the state was handled by malloc(). But this
is no longer the case; everything is under palloc() now.
Use flex yyextra to handle context information, instead of global
variables. This complements the other changes to make the scanner
reentrant.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Andreas Karlsson <andreas@proxel.se>
Discussion: https://www.postgresql.org/message-id/flat/eb6faeac-2a8a-4b69-9189-c33c520e5b7b@eisentraut.org
Use the flex %option reentrant and the bison option %pure-parser to
make the generated scanner and parser pure, reentrant, and
thread-safe.
Make the generated scanner use palloc() etc. instead of malloc() etc.
Previously, we only used palloc() for the buffer, but flex would still
use malloc() for its internal structures. As a result, there could be
some small memory leaks in case of uncaught errors. Now, all the
memory is under palloc() control, so there are no more such issues.
Simplify flex scan buffer management: Instead of constructing the
buffer from pieces and then using yy_scan_buffer(), we can just use
yy_scan_string(), which does the same thing internally.
The previous code was necessary because we allocated the buffer with
palloc() and the rest of the state was handled by malloc(). But this
is no longer the case; everything is under palloc() now.
Use flex yyextra to handle context information, instead of global
variables. This complements the other changes to make the scanner
reentrant.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Co-authored-by: Andreas Karlsson <andreas@proxel.se>
Reviewed-by: Andreas Karlsson <andreas@proxel.se>
Discussion: https://www.postgresql.org/message-id/flat/eb6faeac-2a8a-4b69-9189-c33c520e5b7b@eisentraut.org
Per git log, the last time someone tried to do something with
pgrminclude was around 2011. Many (not all) of the "pgrminclude
ignore" annotations are of a newer date but seem to have just been
copied around during refactorings and file moves and don't seem to
reflect an actual need anymore.
There have been some parallel experiments with include-what-you-use
(IWYU) annotations, but these don't seem to correspond very strongly
to pgrminclude annotations, so there is no value in keeping the
existing ones even for that kind of thing.
So, wipe them all away. We can always add new ones in the future
based on actual needs.
Discussion: https://www.postgresql.org/message-id/flat/2d4dc7b2-cb2e-49b1-b8ca-ba5f7024f05b%40eisentraut.org
5983a4cff added CompactAttribute as an abbreviated alternative to
FormData_pg_attribute to allow more cache-friendly processing in tasks
related to TupleDescs. That commit contained some assert-only code to
check that the CompactAttribute had been populated correctly, however,
the method used to do that checking caused the TupleDesc's
CompactAttribute to be zeroed before it was repopulated and compared to
the snapshot taken before the memset call. This caused issues as the type
cache caches TupleDescs in shared memory which can be used by multiple
backend processes at the same time. There was a window of time between
the zero and repopulation of the CompactAttribute where another process
would mistakenly think that the CompactAttribute is invalid due to the
memset.
To fix this, instead of taking a snapshot of the CompactAttribute and
calling populate_compact_attribute() and comparing the snapshot to the
freshly populated TupleDesc's CompactAttribute, refactor things so we
can just populate a temporary CompactAttribute on the stack. This way
we don't touch the TupleDesc's memory.
Reported-by: Alexander Lakhin, SQLsmith
Discussion: https://postgr.es/m/ca3a256a-5d12-42db-aabe-a75a030d9fb9@gmail.com
These two platforms have a remarkably tight default limit on the
number of SysV semaphores in the system: SEMMNS is only 60
out-of-the-box. Unless manual action is taken to raise that,
we'll only be able to allocate 3 sets of 16 usable semaphores
each, leading to initdb setting max_connections to just 20.
That's problematic because the core regression tests expect
to be able to launch 20 concurrent sessions, leaving us with
no headroom. This seems to be the cause of intermittent
buildfarm failures on some machines.
While there's no getting around the fact that you'd better raise
SEMMNS for production use on these platforms, it does seem desirable
for "make check" to pass reliably without that. We can make that
happen, at least for awhile longer, with two small changes:
* Change sysv_sema.c's SEMAS_PER_SET to 19, so that we can eat up
all of the available semas not just most of them.
* Change initdb to make the smallest max_connections value it will
consider be 25 not 20.
As of HEAD this will leave us with four free semaphores (using the
default values for other relevant parameters such as max_wal_senders).
So we won't need to consider this again until we've invented five
more background processes. Maybe by then we can switch both these
platforms to some other semaphore API.
For the moment, do this only in master; there've not been field
complaints that might justify a back-patch.
Discussion: https://postgr.es/m/db2773a2-aca0-43d0-99c1-060efcd9954e@gmail.com
Reset btpo_cycleid to 0 in btree_xlog_vacuum for consistency with
_bt_delitems_vacuum (the corresponding original execution code). This
makes things neater.
There might be some performance benefit to being consistent like this.
When btvacuumpage doesn't call _bt_delitems_vacuum, it can still
proactively reset btpo_cycleid to 0 via a separate hint-like update
mechanism (it does so whenever it sees that it isn't already set to 0).
And so it's possible that being consistent about resetting btpo_cycleid
like this will save work later on, after standby promotion: subsequent
VACUUMs won't need to clear btpo_cycleid using the hint-like update
mechanism as often as they otherwise would.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Andrey Borodin <x4mmm@yandex-team.ru>
Discussion: https://postgr.es/m/CAH2-Wz=+LDFxn9NZyEsCo8ifcyKt6+n-VLyygySEHgMz+oynqw@mail.gmail.com
A historic snapshot should only be used for catalog access, not
general queries. We never call GetTransactionSnapshot() during logical
decoding, which is good because it wouldn't be very sensible, so the
code to deal with that was unreachable and untested. Turn it into an
error, to avoid doing that in the future either.
Discussion: https://www.postgresql.org/message-id/a868fe78-ddb4-4b0a-9b96-873d91d93cfd@iki.fi
In get_database_list() and get_subscription_list(), the
GetTransactionSnapshot() call is not required because the catalog
table scans use the catalog snapshot, which is held until the end of
the scan. See table_beginscan_catalog(), which calls
RegisterSnapshot(GetCatalogSnapshot(relid)).
In InitPostgres, it's a little less obvious that it's not required,
but still true I believe. All the catalog lookups in InitPostgres()
also use the catalog snapshot, and the looked up values are copied
while still holding the snapshot.
Furthermore, as the removed FIXME comments said, calling
GetTransactionSnapshot() didn't really prevent MyProc->xmin from being
reset anyway.
Discussion: https://www.postgresql.org/message-id/7c56f180-b9e1-481e-8c1d-efa63de3ecbb@iki.fi
Jian He reported the src/include/utility/tcop.h one and the remainder
were found by using a script to look for src/* and check that we have a
filename or directory of that name.
In passing, fix some out-date comments.
Reported-by: Jian He <jian.universality@gmail.com>
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/CACJufxGoE3H-7VgO02=PrR4SNuVWDVbfTyUnwO0HvS-Lxurnog@mail.gmail.com
Library unloading has never been supported with its code removed in
ab02d702ef, and there were some comments still mentioning that it was
a possible operation.
ChangAo has noticed the incorrect references in dfmgr.c, while I have
noticed the other ones while scanning the rest of the tree for similar
mistakes.
Author: ChangAo Chen, Michael Paquier
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/tencent_1D09840A1632D406A610C8C4E2491D74DB0A@qq.com
GetSnapshotData() set TransactionXmin = MyProc->xmin, but when
SnapshotResetXmin() advanced MyProc->xmin, it did not advance
TransactionXmin correspondingly. That meant that TransactionXmin could
be older than MyProc->xmin, and XIDs between than TransactionXmin and
the real MyProc->xmin could be vacuumed away. One known consequence is
in pg_subtrans lookups: we might try to look up the status of an XID
that was already truncated away.
Back-patch to all supported versions.
Reviewed-by: Andres Freund
Discussion: https://www.postgresql.org/message-id/d27a046d-a1e4-47d1-a95c-fbabe41debb4@iki.fi
Here we convert CompactAttribute.attalign from a char, which is directly
derived from pg_attribute.attalign into a uint8, which stores the number
of bytes to align the column's value by in the tuple.
This allows tuple deformation and tuple size calculations to move away
from using the inefficient att_align_nominal() macro, which manually
checks each TYPALIGN_* char to translate that into the alignment bytes
for the given type. Effectively, this commit changes those to TYPEALIGN
calls, which are branchless and only perform some simple arithmetic with
some bit-twiddling.
The removed branches were often mispredicted by CPUs, especially so in
real-world tables which often contain a mishmash of different types
with different alignment requirements.
Author: David Rowley
Reviewed-by: Andres Freund, Victor Yegorov
Discussion: https://postgr.es/m/CAApHDvrBztXP3yx=NKNmo3xwFAFhEdyPnvrDg3=M0RhDs+4vYw@mail.gmail.com
This used to say "nsubxcnt isn't decreased when subtransactions
abort", but there's no variable called nsubxcnt. Commit 8548ddc61b
changed it to "subxcnt", among other typo fixes, but that was wrong
too: the comment actually talks about txn->nsubtxns. That's the field
that's incremented but never decremented and is used for the
allocation earlier in the function.
RelationTruncate() does three things, while holding an
AccessExclusiveLock and preventing checkpoints:
1. Logs the truncation.
2. Drops buffers, even if they're dirty.
3. Truncates some number of files.
Step 2 could previously be canceled if it had to wait for I/O, and step
3 could and still can fail in file APIs. All orderings of these
operations have data corruption hazards if interrupted, so we can't give
up until the whole operation is done. When dirty pages were discarded
but the corresponding blocks were left on disk due to ERROR, old page
versions could come back from disk, reviving deleted data (see
pgsql-bugs #18146 and several like it). When primary and standby were
allowed to disagree on relation size, standbys could panic (see
pgsql-bugs #18426) or revive data unknown to visibility management on
the primary (theorized).
Changes:
* WAL is now unconditionally flushed first
* smgrtruncate() is now called in a critical section, preventing
interrupts and causing PANIC on file API failure
* smgrtruncate() has a new parameter for existing fork sizes,
because it can't call smgrnblocks() itself inside a critical section
The changes apply to RelationTruncate(), smgr_redo() and
pg_truncate_visibility_map(). That last is also brought up to date with
other evolutions of the truncation protocol.
The VACUUM FileTruncate() failure mode had been discussed in older
reports than the ones referenced below, with independent analysis from
many people, but earlier theories on how to fix it were too complicated
to back-patch. The more recently invented cancellation bug was
diagnosed by Alexander Lakhin. Other corruption scenarios were spotted
by me while iterating on this patch and earlier commit 75818b3a.
Back-patch to all supported releases.
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reported-by: rootcause000@gmail.com
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/18146-04e908c662113ad5%40postgresql.org
Discussion: https://postgr.es/m/18426-2d18da6586f152d6%40postgresql.org
The new compact_attrs array stores a few select fields from
FormData_pg_attribute in a more compact way, using only 16 bytes per
column instead of the 104 bytes that FormData_pg_attribute uses. Using
CompactAttribute allows performance-critical operations such as tuple
deformation to be performed without looking at the FormData_pg_attribute
element in TupleDesc which means fewer cacheline accesses.
For some workloads, tuple deformation can be the most CPU intensive part
of processing the query. Some testing with 16 columns on a table
where the first column is variable length showed around a 10% increase in
transactions per second for an OLAP type query performing aggregation on
the 16th column. However, in certain cases, the increases were much
higher, up to ~25% on one AMD Zen4 machine.
This also makes pg_attribute.attcacheoff redundant. A follow-on commit
will remove it, thus shrinking the FormData_pg_attribute struct by 4
bytes.
Author: David Rowley
Reviewed-by: Andres Freund, Victor Yegorov
Discussion: https://postgr.es/m/CAApHDvrBztXP3yx=NKNmo3xwFAFhEdyPnvrDg3=M0RhDs+4vYw@mail.gmail.com
b7493e1ab3 removed leftover mentions of XLOG_HEAP2_FREEZE_PAGE records
from comments but neglected to remove one mention of FREEZE_PAGE.
Reported off-list by Alexander Lakhin
It was reasonable to preserve the old API of BuildTupleHashTable()
in the back branches, but in HEAD we should actively discourage use
of that version. There are no remaining callers in core, so just
get rid of it. Then rename BuildTupleHashTableExt() back to
BuildTupleHashTable().
While at it, fix up the miserably-poorly-maintained header comment
for BuildTupleHashTable[Ext]. It looks like more than one patch in
this area has had the opinion that updating comments is beneath them.
Discussion: https://postgr.es/m/538343.1734646986@sss.pgh.pa.us
Append, MergeAppend, and RecursiveUnion can all use the support
functions added in commit 276279295. The first two can report a
fixed result slot type if all their children return the same fixed
slot type. That does nothing for the append step itself, but might
allow optimizations in the parent plan node. RecursiveUnion can
optimize tuple hash table operations in the same way as SetOp now
does.
Patch by me; thanks to Richard Guo and David Rowley for review.
Discussion: https://postgr.es/m/1850138.1731549611@sss.pgh.pa.us
Remove the code for inserting flag columns in the inputs of a SetOp.
That was the only reason why there would be resjunk columns in a
set-operations plan tree, so we can get rid of some code that
supported that, too.
Get rid of choose_hashed_setop() in favor of building Paths for
the hashed and sorted alternatives, and letting them fight it out
within add_path().
Remove set_operation_ordered_results_useful(), which was giving wrong
answers due to examining the wrong ancestor node: we need to examine
the immediate SetOperationStmt parent not the topmost node. Instead
make each caller of recurse_set_operations() pass down the relevant
parent node. (This thinko seems to have led only to wasted planning
cycles and possibly-inferior plans, not wrong query answers. Perhaps
we should back-patch it, but I'm not doing so right now.)
Teach generate_nonunion_paths() to consider pre-sorted inputs for
sorted SetOps, rather than always generating a Sort node.
Patch by me; thanks to Richard Guo and David Rowley for review.
Discussion: https://postgr.es/m/1850138.1731549611@sss.pgh.pa.us
The original design for set operations involved appending the two
input relations into one and adding a flag column that allows
distinguishing which side each row came from. Then the SetOp node
pries them apart again based on the flag. This is bizarre. The
only apparent reason to do it is that when sorting, we'd only need
one Sort node not two. But since sorting is at least O(N log N),
sorting all the data is actually worse than sorting each side
separately --- plus, we have no chance of taking advantage of
presorted input. On top of that, adding the flag column frequently
requires an additional projection step that adds cycles, and then
the Append node isn't free either. Let's get rid of all of that
and make the SetOp node have two separate children, using the
existing outerPlan/innerPlan infrastructure.
This initial patch re-implements nodeSetop.c and does a bare minimum
of work on the planner side to generate correctly-shaped plans.
In particular, I've tried not to change the cost estimates here,
so that the visible changes in the regression test results will only
involve removal of useless projection steps and not any changes in
whether to use sorted vs hashed mode.
For SORTED mode, we combine successive identical tuples from each
input into groups, and then merge-join the groups. The tuple
comparisons now use SortSupport instead of simple equality, but
the group-formation part should involve roughly the same number of
tuple comparisons as before. The cross-comparisons between left and
right groups probably add to that, but I'm not sure to quantify how
many more comparisons we might need.
For HASHED mode, nodeSetop's logic is almost the same as before,
just refactored into two separate loops instead of one loop that
has an assumption that it will see all the left-hand inputs first.
In both modes, I added early-exit logic to not bother reading the
right-hand relation if the left-hand input is empty, since neither
INTERSECT nor EXCEPT modes can produce any output if the left input
is empty. This could have been done before in the hashed mode, but
not in sorted mode. Sorted mode can also stop as soon as it exhausts
the left input; any remaining right-hand tuples cannot have matches.
Also, this patch adds some infrastructure for detecting whether
child plan nodes all output the same type of tuple table slot.
If they do, the hash table logic can use slightly more efficient
code based on assuming that that's the input slot type it will see.
We'll make use of that infrastructure in other plan node types later.
Patch by me; thanks to Richard Guo and David Rowley for review.
Discussion: https://postgr.es/m/1850138.1731549611@sss.pgh.pa.us
1a0da347a7 replaced Bitmap Table Scan's separate private and
shared bitmap iterators with a unified iterator. It accidentally set up
the prefetch iterator twice for non-parallel bitmap table scans. Remove
the extra set up call to tbm_begin_iterate().
1a0da347a7 replaced Bitmap Table Scan's individual private and
shared iterators with a unified iterator. It neglected, however, to
check if the iterator had already been cleaned up before doing so on
rescan. Add this check both on rescan and end scan to be safe.
Reported-by: Richard Guo
Author: Richard Guo
Discussion: https://postgr.es/m/CAMbWs48nrhcLY1kcd-u9oD%2B6yiS631F_8Fx8ZGsO-BYDwH%2Bbyw%40mail.gmail.com
Consistently reset so->scanBehind at the beginning of nbtree array
advancement, even during sktrig_required=false calls (calls where array
advancement is triggered by an unsatisfied non-required array scan key).
Otherwise, it's possible for queries to fail to return all relevant
tuples to the scan given a low-order required scan key that was
previously deemed "satisfied" by a truncated high key attribute value.
This only happened at the point where a later non-required array scan
key needed to be "advanced" once on the next leaf page (that is, once
the right sibling of the truncated high key page was reached).
The underlying issue was that later code within _bt_advance_array_keys
assumed that the so->scanBehind flag must have been set using the
current page's high key (not the previous page's high key). Any later
successful recheck call to _bt_check_compare would therefore spuriously
be prevented from making _bt_advance_array_keys return true, based on
the faulty belief that the truncated attribute must be from the scan's
current tuple (i.e. the non-pivot tuple at the start of the next page).
_bt_advance_array_keys would return false for the tuple, ultimately
resulting in _bt_checkkeys failing to return a matching tuple.
Oversight in commit 5bf748b8, which enhanced nbtree ScalarArrayOp
execution.
Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-WzkJKncfqyAUTeuB5GgRhT1vhsWO2q11dbZNqKmvjopP_g@mail.gmail.com
Backpatch: 17-, where commit 5bf748b8 first appears.
Use the flex %option reentrant and the bison option %pure-parser to
make the generated scanner and parser pure, reentrant, and
thread-safe.
Make the generated scanner use palloc() etc. instead of malloc() etc.
For the bootstrap scanner and parser, reentrancy and memory management
aren't that important, but we make this change here anyway so that all
the scanners and parsers in the backend use a similar set of options
and APIs.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Andreas Karlsson <andreas@proxel.se>
Discussion: https://www.postgresql.org/message-id/flat/eb6faeac-2a8a-4b69-9189-c33c520e5b7b@eisentraut.org
This adds a new variable-numbered statistics kind in pgstats, where the
object ID key of the stats entries is based on the proc number of the
backends. This acts as an upper-bound for the number of stats entries
that can exist at once. The entries are created when a backend starts
after authentication succeeds, and are removed when the backend exits,
making the stats entry exist for as long as their backend is up and
running. These are not written to the pgstats file at shutdown (note
that write_to_file is disabled, as a safety measure).
Currently, these stats include only information about the I/O generated
by a backend, using the same layer as pg_stat_io, except that it is now
possible to know how much activity is happening in each backend rather
than an overall aggregate of all the activity. A function called
pg_stat_get_backend_io() is added to access this data depending on the
PID of a backend. The existing structure could be expanded in the
future to add more information about other statistics related to
backends, depending on requirements or ideas.
Auxiliary processes are not included in this set of statistics. These
are less interesting to have than normal backends as they have dedicated
entries in pg_stat_io, and stats kinds of their own.
This commit includes also pg_stat_reset_backend_stats(), function able
to reset all the stats associated to a single backend.
Bump catalog version and PGSTAT_FILE_FORMAT_ID.
Author: Bertrand Drouvot
Reviewed-by: Álvaro Herrera, Kyotaro Horiguchi, Michael Paquier, Nazir
Bilal Yavuz
Discussion: https://postgr.es/m/ZtXR+CtkEVVE/LHF@ip-10-97-1-34.eu-west-3.compute.internal
This commit adds pg_stat_io_build_tuples(), a helper routine for
pg_stat_get_io(), that fills its result tuplestore based on the contents
of PgStat_BktypeIO. This will be used in a follow-up commit that uses
the same structures as pg_stat_io for reporting, including the same
object types and contexts, but for a different statistics kind.
Author: Bertrand Drouvot, Michael Paquier
Discussion: https://postgr.es/m/ZtXR+CtkEVVE/LHF@ip-10-97-1-34.eu-west-3.compute.internal
8f4ee9626 fixed an old Assert failure that could happen when the slot
type used to look up the hash table for BuildTupleHashTableExt() users
wasn't a TTSOpsMinimalTuple slot. The fix for that in the back branches
had to be to pass the TupleTableSlotOps as NULL, however in master,
since we have the inputOps parameter as was added by d96d1d515, we can
pass that down instead.
At least one caller uses a fixed slot that's always TTSOpsVirtual, so
passing down inputOps for these cases allows ExecBuildGroupingEqual() to
skip adding the EEOP_INNER_FETCHSOME ExprEvalStep.
This should increase the performance of hashed subplans very slightly.
Author: Tom Lane, David Rowley
Discussion: https://postgr.es/m/2543667.1734483723@sss.pgh.pa.us
If the non-recursive part of a recursive CTE ended up using
TTSOpsBufferHeapTuple as the table slot type, then a duplicate value
could cause an Assert failure in CheckOpSlotCompatibility() when
checking the hash table for the duplicate value. The expected slot type
for the deform step was TTSOpsMinimalTuple so the Assert failed when the
TTSOpsBufferHeapTuple slot was used.
This is a long-standing bug which we likely didn't notice because it
seems much more likely that the non-recursive term would have required
projection and used a TTSOpsVirtual slot, which CheckOpSlotCompatibility
is ok with.
There doesn't seem to be any harm done here other than the Assert
failure. Both TTSOpsMinimalTuple and TTSOpsBufferHeapTuple slot types
require tuple deformation, so the EEOP_*_FETCHSOME ExprState step would
have properly existed in the ExprState.
The solution is to pass NULL for the ExecBuildGroupingEqual's 'lops'
parameter. This means the ExprState's EEOP_*_FETCHSOME step won't
expect a fixed slot type. This makes CheckOpSlotCompatibility() happy as
no checking is performed when the ExprEvalStep is not expecting a fixed
slot type.
Reported-by: Richard Guo
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/CAMbWs4-8U9q2LAtf8+ghV11zeUReA3AmrYkxzBEv0vKnDxwkKA@mail.gmail.com
Backpatch-through: 13, all supported versions
f83d709760 merged the separate XLOG_HEAP2_FREEZE_PAGE records into a
new combined prune, freeze, and vacuum record with opcode
XLOG_HEAP2_PRUNE_VACUUM_SCAN. Remove the last few references to
XLOG_HEAP2_FREEZE_PAGE records which were accidentally left behind.
Reported-by: Tomas Vondra
Reviewed-by: Robert Haas
Discussion: https://postgr.es/m/CA%2BTgmoY1tYff-1CEn8kYt5FsOrynTbtr%3DUZw%3D7mTC1Hv1HpeBQ%40mail.gmail.com
With the repurposing of TBMIterator as an interface for both parallel
and serial iteration through TIDBitmaps in commit 7f9d4187e7,
bitmap table scans may now use it.
Modify bitmap table scan code to use the TBMIterator. This requires
moving around a bit of code, so a few variables are initialized
elsewhere.
Author: Melanie Plageman
Reviewed-by: Tomas Vondra
Discussion: https://postgr.es/m/c736f6aa-8b35-4e20-9621-62c7c82e2168%40vondra.me
Add and use TBMPrivateIterator, which replaces the current TBMIterator
for serial use cases, and repurpose TBMIterator to be a unified
interface for both the serial ("private") and parallel ("shared") TID
Bitmap iterator interfaces. This encapsulation simplifies call sites for
callers supporting both parallel and serial TID Bitmap access.
TBMIterator is not yet used in this commit.
Author: Melanie Plageman
Reviewed-by: Tomas Vondra, Heikki Linnakangas
Discussion: https://postgr.es/m/063e4eb4-32d9-439e-a0b1-75565a9835a8%40iki.fi
HeapScanDescData.rs_cindex and rs_ntuples can't be less than 0. All scan
types using the heap scan descriptor expect these values to be >= 0.
Make that expectation clear by making rs_cindex and rs_ntuples unsigned.
Also remove the test in heapam_scan_bitmap_next_tuple() that checks if
rs_cindex < 0. This was never true, but now that rs_cindex is unsigned,
it makes even less sense.
While we are at it, initialize both rs_cindex and rs_ntuples to 0 in
initscan().
Author: Melanie Plageman
Reviewed-by: Dilip Kumar
Discussion: https://postgr.es/m/CAAKRu_ZxF8cDCM_BFi_L-t%3DRjdCZYP1usd1Gd45mjHfZxm0nZw%40mail.gmail.com
0f5738202 adjusted the execGrouping.c code so it made use of ExprStates to
generate hash values. That commit made a wrong assumption that the slot
type to pass to ExecBuildHash32FromAttrs() is always &TTSOpsMinimalTuple.
That's not the case as the slot type depends on the slot type passed to
LookupTupleHashEntry(), which for nodeRecursiveunion.c, could be any of
the current slot types.
Here we fix this by adding a new parameter to BuildTupleHashTableExt()
to allow the slot type to be passed in. In the case of nodeSubplan.c
and nodeAgg.c the slot type is always &TTSOpsVirtual, so for both of
those cases, it's beneficial to pass the known slot type as that allows
ExecBuildHash32FromAttrs() to skip adding the tuple deform step to the
resulting ExprState. Another possible fix would have been to have
ExecBuildHash32FromAttrs() set "fetch.kind" to NULL so that
ExecComputeSlotInfo() always determines the EEOP_INNER_FETCHSOME is
required, however, that option isn't favorable as slows down aggregation
and hashed subplan evaluation due to the extra (needless) deform step.
Thanks to Nathan Bossart for bisecting to find the offending commit
based on Paul's report.
Reported-by: Paul Ramsey <pramsey@cleverelephant.ca>
Discussion: https://postgr.es/m/99F064C1-B3EB-4BE7-97D2-D2A0AA487A71@cleverelephant.ca
If a dshash table grows very large (e.g., the dshash table for
cumulative statistics when there are millions of tables), resizing
it may fail with an error like:
ERROR: invalid DSA memory alloc request size 1073741824
To fix, permit dshash resizing to allocate more than 1 GB by
providing the DSA_ALLOC_HUGE flag.
Reported-by: Andreas Scherbaum
Author: Matthias van de Meent
Reviewed-by: Cédric Villemain, Michael Paquier, Andres Freund
Discussion: https://postgr.es/m/80a12d59-0d5e-4c54-866c-e69cd6536471%40pgug.de
Backpatch-through: 13
There's no need for set_simple_column_names() to compute unique
column names for join RTEs, because a finished plan tree will
not contain any join alias Vars that we could need names for.
Its other, internal callers will not pass it any join RTEs
anyway, so the upshot is we can just skip join RTEs here.
Aside from getting rid of a klugy against-its-documentation use of
set_relation_column_names, this can speed up EXPLAIN substantially
when considering many-join queries, because the upper join RTEs
tend to have a lot of columns.
Sami Imseih, with cosmetic changes by me
Discussion: https://postgr.es/m/CAA5RZ0th3q-0p1pri58z9grG8r8azmEBa8o1rtkwhLmJg_cH+g@mail.gmail.com
Rename frozen_pages to new_frozen_tuple_pages in LVRelState, the struct
used for tracking state during vacuuming of a heap relation.
frozen_pages sounds like it tracks pages set all-frozen. That is a
misnomer. It only includes pages with at least one newly frozen tuple.
It also includes pages that are not all-frozen.
Author: Melanie Plageman
Reviewed-by: Andres Freund, Masahiko Sawada, Nitin Jadhav, Bilal Yavuz
Discussion: https://postgr.es/m/ctdjzroezaxmiyah3gwbwm67defsrwj2b5fpfs4ku6msfpxeia%40mwjyqlhwr2wu
Formerly we skipped this in bootstrap/check mode and in single-user
mode. That's bad in check mode because it may allow accepting a
value of max_connections that doesn't actually work: on platforms
where semaphores consume file descriptors, there may not be enough
free FDs left over to satisfy fd.c, causing postmaster start to
fail. It's also not great in single-user mode, because fd.c will
operate with just the minimum allowable value of max_safe_fds,
resulting in excess file open/close overhead if anything moderately
complicated is done in single-user mode. (There may be some penalty
for bootstrap mode too, though probably not much.)
Discussion: https://postgr.es/m/2081982.1734393311@sss.pgh.pa.us
Previously we did this in PostmasterMain() and InitPostmasterChild(),
which meant that stack depth checking was disabled in non-postmaster
server processes, for instance in single-user mode. That seems like
a fairly bad idea, since there's no a-priori restriction on the
complexity of queries we will run in single-user mode. Moreover, this
led to not having quite the same stack depth limit in all processes,
which likely has no real-world effect but it offends my inner neatnik.
Setting the depth in main() guarantees that check_stack_depth() is
armed and has a consistent interpretation of stack depth in all forms
of server processes.
While at it, move the code associated with checking the stack depth
out of tcop/postgres.c (which was never a great home for it) into
a new file src/backend/utils/misc/stack_depth.c.
Discussion: https://postgr.es/m/2081982.1734393311@sss.pgh.pa.us
Commit b437571714 allowed parallel builds for BRIN, but left behind
two comments claiming only btree indexes support parallel builds.
Reported by Egor Rogov, along with similar issues in SGML docs.
Backpatch to 17, where parallel builds for BRIN were introduced.
Reported-by: Egor Rogov
Backpatch-through: 17
Discussion: https://postgr.es/m/114e2d5d-125e-07d8-94aa-5ad175fb7443@postgrespro.ru
lowerstr() and lowerstr_with_len() in ts_locale.c do the same thing as
str_tolower() that the rest of the system uses, except that the former
don't use the common locale provider framework but instead use the
global libc locale settings.
This patch replaces uses of lowerstr*() with str_tolower(...,
DEFAULT_COLLATION_OID). For instances that use a libc locale
globally, this will result in exactly the same behavior. For
instances that use other locale providers, you now get consistent
behavior and are no longer dependent on the libc locale settings (for
this case; there are others).
Most uses of these functions are for processing dictionary and
configuration files. In those cases, using the default collation
seems appropriate. At least we don't have a more specific collation
available. But the code in contrib/pg_trgm should really depend on
the collation of the columns being processed. This is not done here,
this can be done in a separate patch.
(You can probably construct some edge cases where this change would
create some locale-related upgrade incompatibility, for example if
before you used a combination of ICU and a differently-behaving libc
locale. We can document this in the release notes, but I don't think
there is anything more we can do about this.)
Reviewed-by: Jeff Davis <pgsql@j-davis.com>
Discussion: https://www.postgresql.org/message-id/flat/653f3b84-fc87-45a7-9a0c-bfb4fcab3e7d%40eisentraut.org
These do the same thing as the standard isdigit(), isspace(), and
isprint() but with multibyte and encoding support. But all the
callers are only interested in analyzing single-byte ASCII characters.
So this extra layer is overkill and we can replace the uses with the
standard functions.
All the t_is*() functions in ts_locale.c are under scrutiny because
they don't use the common locale provider framework but instead use
the global libc locale settings. For the functions being touched by
this patch, we don't need all that anyway, as mentioned above, so the
simplest solution is to just remove them. The few remaining t_is*()
functions will need a different treatment in a separate patch.
pg_trgm has some compile-time options with macros such as
KEEPONLYALNUM. These are not documented, and the non-default variant
is not supported by any test cases. As part of this undertaking, I'm
removing the non-default variant, as it is in the way of cleanup. So
in this case, the not-KEEPONLYALNUM code path is gone.
Reviewed-by: Jeff Davis <pgsql@j-davis.com>
Discussion: https://www.postgresql.org/message-id/flat/653f3b84-fc87-45a7-9a0c-bfb4fcab3e7d%40eisentraut.org
When pulling up a subquery that is under an outer join, if the
subquery's target list contains a strict expression that uses a
subquery variable, it's okay to pull up the expression without
wrapping it in a PlaceHolderVar: if the subquery variable is forced to
NULL by the outer join, the expression result will come out as NULL
too.
If the strict expression does not contain any subquery variables, the
current code always wraps it in a PlaceHolderVar. While this is not
incorrect, the analysis could be tighter: if the strict expression
contains any variables of rels that are under the same lowest nulling
outer join as the subquery, we can also avoid wrapping it. This is
safe because if the subquery variable is forced to NULL by the outer
join, the variables of rels that are under the same lowest nulling
outer join will also be forced to NULL, resulting in the expression
evaluating to NULL as well. Therefore, it's not necessary to force
the expression to be evaluated below the outer join. It could be
beneficial to get rid of such PHVs because they could imply lateral
dependencies, which force us to resort to nestloop joins.
This patch checks if the lateral references in the strict expression
contain any variables of rels under the same lowest nulling outer join
as the subquery, and avoids wrapping the expression in that case.
This is fundamentally a generalization of the optimizations for bare
Vars and PHVs introduced in commit f64ec81a8.
No backpatch as this could result in plan changes.
Author: Richard Guo
Discussion: https://postgr.es/m/CAMbWs4_ENtfRdLaM_bXAxiKRYO7DmwDBDG4_2=VTDi0mJP-jAw@mail.gmail.com
The following commands gain some information about the error position in
the query, should they fail when looking at the type used:
- CREATE TYPE (LIKE)
- CREATE TABLE OF
Both are related to typenameType() where the type name lookup is done.
These calls gain the ParseState that already exists in these paths.
Author: Kirill Reshke, Jian He
Reviewed-by: Álvaro Herrera, Michael Paquier
Discussion: https://postgr.es/m/CALdSSPhqfvKbDwqJaY=yEePi_aq61GmMpW88i6ZH7CMG_2Z4Cg@mail.gmail.com
Create API entry points pg_strlower(), etc., that work with any
provider and give the caller control over the destination
buffer. Then, move provider-specific logic into pg_locale_builtin.c,
pg_locale_icu.c, and pg_locale_libc.c as appropriate.
Discussion: https://postgr.es/m/7aa46d77b377428058403723440862d12a8a129a.camel@j-davis.com
This is simply done by pushing down the ParseState available in
ProcessUtility() to DefineDomain(), giving more information about the
position of an error when running a CREATE DOMAIN query.
Most of the queries impacted by this change have been added previously
in 0172b4c944.
Author: Kirill Reshke, Jian He
Reviewed-by: Álvaro Herrera, Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/CALdSSPhqfvKbDwqJaY=yEePi_aq61GmMpW88i6ZH7CMG_2Z4Cg@mail.gmail.com
I went through the buildfarm's reports of "warning: variable 'foo'
might be clobbered by 'longjmp' or 'vfork' [-Wclobbered]". As usual,
none of them are live problems according to my understanding of the
effects of setjmp/longjmp, to wit that local variables might revert
to their values as of PG_TRY entry, due to being kept in registers.
But I did happen to notice that XmlTableGetValue's "cstr" variable
doesn't need to be declared outside the PG_TRY block at all (thus
giving further proof that the -Wclobbered warning has little
connection to real problems). We might as well move it inside,
and "cur" too, in hopes of eliminating one of the bogus warnings.
POSIX says that the global variable environ shouldn't be declared in a
header, and that you have to declare it yourself. MinGW declares it in
<stdlib.h> with some macrology that messes up our declarations. Visual
Studio doesn't warn (there are clues that it may also declare it, but if
so, apparently compatibly). Suppress our declarations, on MinGW only.
This clears the last warnings on CI's optional MinGW task, and hopefully
on build farm animal fairywren too.
Like 1319997d, no back-patch for now as it's not known to be breaking
anything, and my humble goal is just to keep the MinGW build clean going
forward.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> (earlier version)
Discussion: https://postgr.es/m/CA%2BhUKGJLMh%2B6W5E4M_jSFb43gnrA_-Q6-%2BBf3HkBXyGfRFcBsQ%40mail.gmail.com
Commits 7bb3102c and 3eb77eba removed the only user of the
EXTENSION_DONT_CHECK_SIZE flag, which had previously been required to
checkpoint truncated relations. Since 7bb3102c, segments have been
opened directly for synchronization without calling _mdfd_getseg(), so
it doesn't need a mode that tolerates non-final short segments. Remove
the redundant flag and associated comments.
Reported-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/nyj4k7yur5t27rtygvx2i2lrlp6rqfvvhoiiwx4fznynksf2et%404hj2sp42alpe
This reverts commit 562bee0fc1.
We received a report from the field about this change in behavior,
so it seems best to revert this commit and to add proper
multibyte-aware truncation as a follow-up exercise.
Fixes bug #18711.
Reported-by: Adam Rauch
Reviewed-by: Tom Lane, Bertrand Drouvot, Bruce Momjian, Thomas Munro
Discussion: https://postgr.es/m/18711-7503ee3e449d2c47%40postgresql.org
Backpatch-through: 17
d4c3a156c added support that when the GROUP BY contained all of the
columns belonging to a relation's PRIMARY KEY, all other columns
belonging to that relation would be removed from the GROUP BY clause.
That's possible because all other columns are functionally dependent on
the PRIMARY KEY and those columns alone ensure the groups are distinct.
Here we expand on that optimization and allow it to work for any unique
indexes on the table rather than just the PRIMARY KEY index. This
normally requires that all columns in the index are defined with NOT NULL,
however, we can relax that requirement when the index is defined with
NULLS NOT DISTINCT.
When there are multiple suitable indexes to allow columns to be removed,
we prefer the index with the least number of columns as this allows us
to remove the highest number of GROUP BY columns. One day, we may want to
revisit that decision as it may make more sense to use the narrower set of
columns in terms of the width of the data types and stored/queried data.
This also adjusts the code to make use of RelOptInfo.indexlist rather
than looking up the catalog tables.
In passing, add another short-circuit path to allow bailing out earlier
in cases where it's certainly not possible to remove redundant GROUP BY
columns. This early exit is now cheaper to do than when this code was
originally written as 00b41463c made it cheaper to check for empty
Bitmapsets.
Patch originally by Zhang Mingli and later worked on by jian he, but after
I (David) worked on it, there was very little of the original left.
Author: Zhang Mingli, jian he, David Rowley
Reviewed-by: jian he, Andrei Lepikhov
Discussion: https://postgr.es/m/327990c8-b9b2-4b0c-bffb-462249f82de0%40Spark
Traditionally, remove_useless_groupby_columns() was called during
grouping_planner() directly after the call to preprocess_groupclause().
While in many ways, it made sense to populate the field and remove the
functionally dependent columns from processed_groupClause at the same
time, it's just that doing so had the disadvantage that
remove_useless_groupby_columns() was being called before the RelOptInfos
were populated for the relations mentioned in the query. Not having
RelOptInfos available meant we needed to manually query the catalog tables
to get the required details about the primary key constraint for the
table.
Here we move the remove_useless_groupby_columns() call to
query_planner() and put it directly after the RelOptInfos are populated.
This is fine to do as processed_groupClause still isn't final at this
point as it can still be modified inside standard_qp_callback() by
make_pathkeys_for_sortclauses_extended().
This commit is just a refactor and simply moves
remove_useless_groupby_columns() into initsplan.c. A planned follow-up
commit will adjust that function so it uses RelOptInfo instead of doing
catalog lookups and also teach it how to use unique indexes as proofs to
expand the cases where we can remove functionally dependent columns from
the GROUP BY.
Reviewed-by: Andrei Lepikhov, jian he
Discussion: https://postgr.es/m/CAApHDvqLezKwoEBBQd0dp4Y9MDkFBDbny0f3SzEeqOFoU7Z5+A@mail.gmail.com
This commit introduces the uuidv7() SQL function, which generates UUID
version 7 as specified in RFC 9652. UUIDv7 combines a Unix timestamp
in milliseconds and random bits, offering both uniqueness and
sortability.
In our implementation, the 12-bit sub-millisecond timestamp fraction
is stored immediately after the timestamp, in the space referred to as
"rand_a" in the RFC. This ensures additional monotonicity within a
millisecond. The rand_a bits also function as a counter. We select a
sub-millisecond timestamp so that it monotonically increases for
generated UUIDs within the same backend, even when the system clock
goes backward or when generating UUIDs at very high
frequency. Therefore, the monotonicity of generated UUIDs is ensured
within the same backend.
This commit also expands the uuid_extract_timestamp() function to
support UUID version 7.
Additionally, an alias uuidv4() is added for the existing
gen_random_uuid() SQL function to maintain consistency.
Bump catalog version.
Author: Andrey Borodin
Reviewed-by: Sergey Prokhorenko, Przemysław Sztoch, Nikolay Samokhvalov
Reviewed-by: Peter Eisentraut, Jelte Fennema-Nio, Aleksander Alekseev
Reviewed-by: Masahiko Sawada, Lukas Fittl, Michael Paquier, Japin Li
Reviewed-by: Marcos Pegoraro, Junwang Zhao, Stepan Neretin
Reviewed-by: Daniel Vérité
Discussion: https://postgr.es/m/CAAhFRxitJv%3DyoGnXUgeLB_O%2BM7J2BJAmb5jqAT9gZ3bij3uLDA%40mail.gmail.com
There are a few places in this file that use memset() and memcmp()
to determine whether a section of memory is all zeros. This commit
modifies them to use pg_memory_is_all_zeros() instead. These
aren't expected to be hot code paths, but this may optimize them a
bit. Plus, this allows us to remove some variables that were only
needed for the memset() and memcmp().
Author: Bertrand Drouvot
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/Z1hNubHfvMxlW6eu%40ip-10-97-1-34.eu-west-3.compute.internal
The topic of turning EXPLAIN's BUFFERS option on with the ANALYZE option
has come up a few times over the past few years. In many ways, doing this
seems like a good idea as it may be more obvious to users why a given
query is running more slowly than they might expect. Also, from my own
(David's) personal experience, I've seen users posting to the mailing
lists with two identical plans, one slow and one fast asking why their
query is sometimes slow. In many cases, this is due to additional reads.
Having BUFFERS on by default may help reduce some of these questions, and
if not, make it more obvious to the user before they post, or save a
round-trip to the mailing list when additional I/O effort is the cause of
the slowness.
The general consensus is that we want BUFFERS on by default with
ANALYZE. However, there were more than zero concerns raised with doing
so. The primary reason against is the additional verbosity, making it
harder to read large plans. Another concern was that buffer information
isn't always useful so may not make sense to have it on by default.
It's currently December, so let's commit this to see if anyone comes
forward with a strong objection against making this change. We have over
half a year remaining in the v18 cycle where we could still easily consider
reverting this if someone were to come forward with a convincing enough
reason as to why doing this is a bad idea.
There were two patches independently submitted to achieve this goal, one
by me and the other by Guillaume. This commit is a mix of both of these
patches with some additional work done by me to adjust various
additional places in the documentation which include EXPLAIN ANALYZE
output.
Author: Guillaume Lelarge, David Rowley
Reviewed-by: Robert Haas, Greg Sabino Mullane, Michael Christofides
Discussion: https://postgr.es/m/CANNMO++W7MM8T0KyXN3ZheXXt-uLVM3aEtZd+WNfZ=obxffUiA@mail.gmail.com
This speeds up obtaining hash values for GROUP BY and hashed SubPlans by
using the ExprState support for hashing, thus allowing JIT compilation for
obtaining hash values for these operations.
This, even without JIT compilation, has been shown to improve Hash
Aggregate performance in some cases by around 15% and hashed NOT IN
queries in one case by over 30%, however, real-world cases are likely to
see smaller gains as the test cases used were purposefully designed to
have high hashing overheads by keeping the hash table small to prevent
additional memory overheads that would be a factor when working with large
hash tables.
In passing, fix a hypothetical bug in ExecBuildHash32Expr() so that the
initial value is stored directly in the ExprState's result field if
there are no expressions to hash. None of the current users of this
function use an initial value, so the bug is only hypothetical.
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Discussion: https://postgr.es/m/CAApHDvpYSO3kc9UryMevWqthTBrxgfd9djiAjKHMPUSQeX9vdQ@mail.gmail.com
Hashing of a single Var is a very common operation for ExprState to
perform. Here we add dedicated ExecJust* functions which helps speed up
Hash Joins by removing the interpretation overhead in ExecInterpExpr().
This change currently only affects Hash Joins on a single column. Hash
Joins with multiple join keys or an expression still run through
ExecInterpExpr().
Some testing has shown up to 10% query performance increases on recent AMD
hardware and nearly 7% increase on an Apple M2 for a query performing a
hash join with a large number of lookups on a small hash table.
This change was extracted from a larger patch which adjusts GROUP BY /
hashed subplans / hashed set operations to use ExprState hashing.
Discussion: https://postgr.es/m/CAApHDvr8Zc0ZgzVoCZLdHGOFNhiJeQ6vrUcS9V7N23zMWQb-eA@mail.gmail.com
Robert Haas expressed concern about whether commit 3eea7a0c9 exposed
the parallel-execution machinery to a case it isn't tested for, namely
a second non-parallel execution of a plan after a parallel execution.
Investigation shows that that can't happen because of pquery.c's
manipulation of the scan direction, but it sure wasn't obvious to
start with. Add some commentary about that.
Discussion: https://postgr.es/m/CA+TgmoagyKQy=HFw+wLo0AKTYWHui+iKswZ8Jnqqd-cFby-WVg@mail.gmail.com
Since commit 97550c0711, these failed with
"PANIC: proc_exit() called in child process" due to uninitialized or
stale MyProcPid. That was reachable if close() failed in
ClosePostmasterPorts() or setlocale(category, "C") failed, both
unlikely. Back-patch to v13 (all supported versions).
Discussion: https://postgr.es/m/20241208034614.45.nmisch@google.com
A WITHOUT OVERLAPS primary key or unique constraint is accepted as a
REPLICA IDENTITY, since it guarantees uniqueness. But subscribers
applying logical decoding messages would fail because there was not
support for looking up the equals operator for a gist index. This
fixes that: For GiST indexes we can use the stratnum GiST support
function.
Reviewed-by: Paul Jungwirth <pj@illuminatedcomputing.com>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
IsIndexUsableForReplicaIdentityFull() described a number of conditions
that a suitable index has to fulfill. But not all of these were
actually checked in the code. Instead, it appeared to rely on
get_equal_strategy_number() to filter out any indexes that are not
btree or hash. As we look to generalize index AM capabilities, this
would possibly break if we added additional support in
get_equal_strategy_number(). Instead, write out code to check for the
required capabilities explicitly. This shouldn't change any behaviors
at the moment.
Reviewed-by: Paul Jungwirth <pj@illuminatedcomputing.com>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
get_equal_strategy_number_for_am() gets the equal strategy number for
an AM. This currently only supports btree and hash. In the more
general case, this also depends on the operator class (see for example
GistTranslateStratnum()). To support that, replace this function with
get_equal_strategy_number() that takes an opclass and derives it from
there. (This function already existed before as a static function, so
the signature is kept for simplicity.)
This patch is only a refactoring, it doesn't add support for other
index AMs such as gist. This will be done separately.
Reviewed-by: Paul Jungwirth <pj@illuminatedcomputing.com>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
This "shouldn't happen", except right now it can with a temporal gist
index (to be fixed soon), because of missing gist support in
get_equal_strategy_number(). But right now, the error is not caught
right away, but instead you get the subsequent error about a "missing
operator 0". This makes the error more accurate.
Author: Paul Jungwirth <pj@illuminatedcomputing.com>
Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
The GUC assign and check hooks used "assign_timezone_abbreviations",
which was incorrect.
Issue noticed while browsing this area of the code, introduced in
0a20ff54f5.
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/Z1eV6Y8yk77GZhZI@paquier.xyz
Backpatch-through: 16
Follow-up commit to a9d58bfe8a. Backpatch down to v16 where
this was added in order to keep the code consistent for future
backpatches.
Author: Tofig Aliev <t.aliev@postgrespro.ru>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/bba4313fdde9db46db279f96f3b748b1@postgrespro.ru
Backpatch-through: 16
This commit makes use of the overflow-aware routines in int.h to
fix a variety of reported overflow bugs in the date and timestamp
code. It seems unlikely that this fixes all such bugs in this
area, but since the problems seem limited to cases that are far
beyond any realistic usage, I'm not going to worry too much. Note
that for one bug, I've chosen to simply add a comment about the
overflow hazard because fixing it would require quite a bit of code
restructuring that doesn't seem worth the risk.
Since this is a bug fix, it could be back-patched, but given the
risk of conflicts with the new routines in int.h and the overall
risk/reward ratio of this patch, I've opted not to do so for now.
Fixes bug #18585 (except for the one case that's just commented).
Reported-by: Alexander Lakhin
Author: Matthew Kim, Nathan Bossart
Reviewed-by: Joseph Koshakow, Jian He
Discussion: https://postgr.es/m/31ad2cd1-db94-bdb3-f91a-65ffdb4bef95%40gmail.com
Discussion: https://postgr.es/m/18585-db646741dd649abd%40postgresql.org
Our parallel-mode code only works when we are executing a query
in full, so ExecutePlan must disable parallel mode when it is
asked to do partial execution. The previous logic for this
involved passing down a flag (variously named execute_once or
run_once) from callers of ExecutorRun or PortalRun. This is
overcomplicated, and unsurprisingly some of the callers didn't
get it right, since it requires keeping state that not all of
them have handy; not to mention that the requirements for it were
undocumented. That led to assertion failures in some corner
cases. The only state we really need for this is the existing
QueryDesc.already_executed flag, so let's just put all the
responsibility in ExecutePlan. (It could have been done in
ExecutorRun too, leading to a slightly shorter patch -- but if
there's ever more than one caller of ExecutePlan, it seems better
to have this logic in the subroutine than the callers.)
This makes those ExecutorRun/PortalRun parameters unnecessary.
In master it seems okay to just remove them, returning the
API for those functions to what it was before parallelism.
Such an API break is clearly not okay in stable branches,
but for them we can just leave the parameters in place after
documenting that they do nothing.
Per report from Yugo Nagata, who also reviewed and tested
this patch. Back-patch to all supported branches.
Discussion: https://postgr.es/m/20241206062549.710dc01cf91224809dd6c0e1@sraoss.co.jp
Remove the 'whenTaken' and 'lsn' fields from SnapshotData. After the
removal of the "snapshot too old" feature, they were never set to a
non-zero value.
This largely reverts commit 3e2f3c2e42, which added the
OldestActiveSnapshot tracking, and the init_toast_snapshot()
function. That was only required for setting the 'whenTaken' and 'lsn'
fields. SnapshotToast is now a constant again, like SnapshotSelf and
SnapshotAny. I kept a thin get_toast_snapshot() wrapper around
SnapshotToast though, to check that you have a registered or active
snapshot. That's still a useful sanity check.
Reviewed-by: Nathan Bossart, Andres Freund, Tom Lane
Discussion: https://www.postgresql.org/message-id/cd4b4f8c-e63a-41c0-95f6-6e6cd9b83f6d@iki.fi
When pulling up a lateral subquery that is under an outer join, the
current code always wraps a Var or PHV in the subquery's targetlist
into a new PlaceHolderVar if it is a lateral reference to something
outside the subquery. This is necessary when the Var/PHV references
the non-nullable side of the outer join from the nullable side: we
need to ensure that it is evaluated at the right place and hence is
forced to null when the outer join should do so. However, if the
referenced rel is under the same lowest nulling outer join, we can
actually omit the wrapping. That's safe because if the subquery
variable is forced to NULL by the outer join, the lateral reference
variable will come out as NULL too. It could be beneficial to get rid
of such PHVs because they imply lateral dependencies, which force us
to resort to nestloop joins.
This patch leverages the newly introduced nullingrel_info to check if
the nullingrels of the subquery RTE are a subset of those of the
laterally referenced rel, in order to determine if the referenced rel
is under the same lowest nulling outer join.
No backpatch as this could result in plan changes.
Author: Richard Guo
Reviewed-by: James Coleman, Dmitry Dolgov, Andrei Lepikhov
Discussion: https://postgr.es/m/CAMbWs48uk6C7Z9m_FNT8_21CMCk68hrgAsz=z6zpP1PNZMkeoQ@mail.gmail.com
When resetting a HashJoin node for rescans, if it is a single-batch
join and there are no parameter changes for the inner subnode, we can
just reuse the existing hash table without rebuilding it. However,
for join types that depend on the inner-tuple match flags in the hash
table, we need to reset these match flags to avoid incorrect results.
This applies to right, right-anti, right-semi, and full joins.
When I introduced "Right Semi Join" plan shapes in aa86129e1, I failed
to reset the match flags in the hash table for right-semi joins in
rescans. This oversight has been shown to produce incorrect results.
This patch fixes it.
Author: Richard Guo
Discussion: https://postgr.es/m/CAMbWs4-nQF9io2WL2SkD0eXvfPdyBc9Q=hRwfQHCGV2usa0jyA@mail.gmail.com
The pgoutput module caches publication names in a list and frees it upon
invalidation. However, the code forgot to free the actual publication
names within the list elements, as publication names are pstrdup()'d in
GetPublication(). This would cause memory to leak in
CacheMemoryContext, bloating it over time as this context is not
cleaned.
This is a problem for WAL senders running for a long time, as an
accumulation of invalidation requests would bloat its cache memory
usage. A second case, where this leak is easier to see, involves a
backend calling SQL functions like pg_logical_slot_{get,peek}_changes()
which create a new decoding context with each execution. More
publications create more bloat.
To address this, this commit adds a new memory context within the
logical decoding context and resets it each time the publication names
cache is invalidated, based on a suggestion from Amit Kapila. This
ensures that the lifespan of the publication names aligns with that of
the logical decoding context.
This solution changes PGOutputData, which is fine for HEAD but it could
cause an ABI breakage in stable branches as the structure size would
change, so these are left out for now.
Analyzed-by: Michael Paquier, Jeff Davis
Author: Zhijie Hou
Reviewed-by: Michael Paquier, Masahiko Sawada, Euler Taveira
Discussion: https://postgr.es/m/Z0khf9EVMVLOc_YY@paquier.xyz
pgstat_write_statsfile() discards any entries marked as dropped from
being written to the stats file at shutdown, and also included an
assertion based on the same condition.
The intention of the assertion is to track that no pgstats entries
should be left around as terminating backends should drop any entries
they still hold references on before the stats file is written by the
checkpointer, and it not worth taking down the server in this case if
there is a bug making that possible.
Let's improve the comment of this area to document clearly what's
intended.
Based on a discussion with Bertrand Drouvot and Anton A. Melnikov.
Author: Bertrand Drouvot
Discussion: https://postgr.es/m/a13e8cdf-b97a-4ecb-8f42-aaa367974e29@postgrespro.ru
Backpatch-through: 15
The error detail message "Replica identity consists of an unpublished
generated column." implies that the entire replica identity is made up of
an unpublished generated column which may not be the case.
Reported-by: Peter Smith
Author: Shlok Kyal
Reviewed-by: Peter Smith, Amit Kapila
Discussion: https://postgr.es/m/CAHut+PuwMhKx0PhOA4APhJTLoBGNykbeCQpr_CuwGT-SkswG5w@mail.gmail.com
818119afcc has introduced the "generation" concept in pgstats entries,
incremented a counter when a pgstats entry is reinitialized, but it did
not count on the fact that backends still holding local references to
such entries need to be refreshed if the cache age is outdated. The
previous logic only updated local references when an entry was dropped,
but it needs also to consider entries that are reinitialized.
This matters for replication slot stats (as well as custom pgstats kinds
in 18~), where concurrent drops and creates of a slot could cause
incorrect stats to be locally referenced. This would lead to an
assertion failure at shutdown when writing out the stats file, as the
backend holding an outdated local reference would not be able to drop
during its shutdown sequence the stats entry that should be dropped, as
the last process holding a reference to the stats entry. The
checkpointer was then complaining about such an entry late in the
shutdown sequence, after the shutdown checkpoint is finished with the
control file updated, causing the stats file to not be generated. In
non-assert builds, the entry would just be skipped with the stats file
written.
Note that only logical replication slots use statistics.
A test case based on TAP is added to test_decoding, where a persistent
connection peeking at a slot's data is kept with concurrent drops and
creates of the same slot. This is based on the isolation test case that
Anton has sent. As it requires a node shutdown with a check to make
sure that the stats file is written with this specific sequence of
events, TAP is used instead.
Reported-by: Anton A. Melnikov
Reviewed-by: Bertrand Drouvot
Discussion: https://postgr.es/m/56bf8ff9-dd8c-47b2-872a-748ede82af99@postgrespro.ru
Backpatch-through: 15
When short-circuiting WindowAgg node evaluation on the top-level
WindowAgg node using quals on monotonic window functions, because the
WindowAgg run condition can mean there's no need to evaluate subsequent
window function results in the same partition once the run condition
becomes false, it was possible that the executor would use stale results
from the previous invocation of the window function in some cases.
A fix for this was partially done by a5832722, but that commit only
fixed the issue for non-top-level WindowAgg nodes. I mistakenly thought
that the top-level WindowAgg didn't have this issue, but Jayesh's example
case clearly shows that's incorrect. At the time, I also thought that
this only affected 32-bit systems as all window functions which then
supported run conditions returned BIGINT, however, that's wrong as
ExecProject is still called and that could cause evaluation of any other
window function belonging to the same WindowAgg node, one of which may
return a byref type.
The only queries affected by this are WindowAggs with a "Run Condition"
which contains at least one window function with a byref result type,
such as lead() or lag() on a byref column. The window clause must also
contain a PARTITION BY clause (without a PARTITION BY, execution of the
WindowAgg stops immediately when the run condition becomes false and
there's no risk of using the stale results).
Reported-by: Jayesh Dehankar
Discussion: https://postgr.es/m/193261e2c4d.3dd3cd7c1842.871636075166132237@zohocorp.com
Backpatch-through: 15, where WindowAgg run conditions were added
Usually an entry in pg_amop or pg_amproc does not need a dependency on
its amoplefttype/amoprighttype/amproclefttype/amprocrighttype types,
because there is an indirect dependency via the argument types of its
referenced operator or procedure, or via the opclass it belongs to.
However, for some support procedures in some index AMs, the argument
types of the support procedure might not mention the column data type
at all. Also, the amop/amproc entry might be treated as "loose" in
the opfamily, in which case it lacks a dependency on any particular
opclass; or it might be a cross-type entry having a reference to a
datatype that is not its opclass' opcintype.
The upshot of all this is that there are cases where a datatype can
be dropped while leaving behind amop/amproc entries that mention it,
because there is no path in pg_depend showing that those entries
depend on that type. Such entries are harmless in normal activity,
because they won't get used, but they cause problems for maintenance
actions such as dropping the operator family. They also cause pg_dump
to produce bogus output. The previous commit put a band-aid on the
DROP OPERATOR FAMILY failure, but a real fix is needed.
To fix, add pg_depend entries showing that a pg_amop/pg_amproc entry
depends on its lefttype/righttype. To avoid bloating pg_depend too
much, skip this if the referenced operator or function has that type
as an input type. (I did not bother with considering the possible
indirect dependency via the opclass' opcintype; at least in the
reported case, that wouldn't help anyway.)
Probably, the reason this has escaped notice for so long is that
add-on datatypes and relevant opclasses/opfamilies are usually
packaged as extensions nowadays, so that there's no way to drop
a type without dropping the referencing opclasses/opfamilies too.
Still, in the absence of pg_depend entries there's nothing that
constrains DROP EXTENSION to drop the opfamily entries before the
datatype, so it seems possible for a DROP failure to occur anyway.
The specific case that was reported doesn't fail in v13, because
v13 prefers to attach the support procedure to the opclass not the
opfamily. But it's surely possible to construct other edge cases
that do fail in v13, so patch that too.
Per report from Yoran Heling. Back-patch to all supported branches.
Discussion: https://postgr.es/m/Z1MVCOh1hprjK5Sf@gmai021
Yoran Heling reported a case where a data type could be dropped
while references to its OID remain behind in pg_amproc. This
causes getObjectDescription to fail, which blocks dropping the
operator family (since our DROP code likes to construct descriptions
of everything it's dropping). The proper fix for this requires
adding more pg_depend entries. But to allow DROP to go through with
already-corrupt catalogs, tweak getObjectDescription to print "???"
for the type instead of failing when it processes such an entry.
I changed the logic for pg_amop similarly, for consistency,
although it is not known that the problem can manifest in pg_amop.
Per report from Yoran Heling. Back-patch to all supported
branches (although the problem may be unreachable in v13).
Discussion: https://postgr.es/m/Z1MVCOh1hprjK5Sf@gmai021
These format codes produce or consume strings of digits, so they
should be labeled with is_digit = true, but they were not.
This has effect in only one place, where is_next_separator()
is checked to see if the preceding format code should slurp up
all the available digits. Thus, with a format such as '...SSFF3'
with remaining input '12345', the 'SS' code would consume all
five digits (and then complain about seconds being out of range)
when it should eat only two digits.
Per report from Nick Davies. This bug goes back to d589f9446
where the FFn codes were introduced, so back-patch to v13.
Discussion: https://postgr.es/m/AM8PR08MB6356AC979252CFEA78B56678B6312@AM8PR08MB6356.eurprd08.prod.outlook.com
Before this patch, misplacing a special must-be-first option for
dispatching to a subprogram (e.g., postgres -D . --single) would
fail with an error like
FATAL: --single requires a value
This patch adjusts this error to more accurately complain that the
special option wasn't listed first. The aforementioned error
message now looks like
FATAL: --single must be first argument
The dispatch option parsing code has been refactored for use
wherever ParseLongOption() is called. Beyond the obvious advantage
of avoiding code duplication, this should prevent similar problems
when new dispatch options are added. Note that we assume that none
of the dispatch option names match another valid command-line
argument, such as the name of a configuration parameter.
Ideally, we'd remove this must-be-first requirement for these
options, but after some investigation, we decided that wasn't worth
the added complexity and behavior changes.
Author: Nathan Bossart, Greg Sabino Mullane
Reviewed-by: Greg Sabino Mullane, Peter Eisentraut, Álvaro Herrera, Tom Lane
Discussion: https://postgr.es/m/CAKAnmmJkZtZAiSryho%3DgYpbvC7H-HNjEDAh16F3SoC9LPu8rqQ%40mail.gmail.com
parallel_vacuum_reset_dead_items used a local variable to hold a
pointer from the passed vacrel, purely as a shorthand. This pointer
was later freed and a new allocation was made and stored to the
struct. Then the local pointer was mistakenly referenced again.
This apparently happened not to break anything since the freed chunk
would have been put on the context's freelist, so it was accidentally
the same pointer anyway, in which case the DSA handle was correctly
updated. The minimal fix is to change two places so they access
dead_items through the vacrel. This coding style is a maintenance
hazard, so while at it get rid of most other similar usages, which
were inconsistently used anyway.
Analysis and patch by Vallimaharajan G, with further defensive coding
by me
Backpath to v17, when TidStore came in
Discussion: https://postgr.es/m/1936493cc38.68cb2ef27266.7456585136086197135@zohocorp.com
Ensure stored generated columns that are part of REPLICA IDENTITY must be
published explicitly for UPDATE and DELETE operations to be published. We
can publish generated columns by listing them in the column list or by
enabling the publish_generated_columns option.
This commit changes the behavior of the test added in commit adedf54e65 by
giving an ERROR for the UPDATE operation in such cases. There is no way to
trigger the bug reported in commit adedf54e65 but we didn't remove the
corresponding code change because it is still relevant when replicating
changes from a publisher with version less than 18.
We decided not to backpatch this behavior change to avoid the risk of
breaking existing output plugins that may be sending generated columns by
default although we are not aware of any such plugin. Also, we didn't see
any reports related to this on STABLE branches which is another reason not
to backpatch this change.
Author: Shlok Kyal, Hou Zhijie
Reviewed-by: Vignesh C, Amit Kapila
Discussion: https://postgr.es/m/CANhcyEVw4V2Awe2AB6i0E5AJLNdASShGfdBLbUd1XtWDboymCA@mail.gmail.com
The validate_sync_standby_slots subroutine requires an LWLock, so it
cannot run in processes without PGPROC; skip it there to avoid a crash.
This replaces the current test for ReplicationSlotCtl being not null,
which appears to be a solution for the same problem but less general.
I also rewrote a related comment that mentioned ReplicationSlotCtl in
StandbySlotsHaveCaughtup.
This code came in with commit bf279ddd1c28; backpatch to 17.
Reported-by: Gabriele Bartolini <gabriele.bartolini@enterprisedb.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Zhijie Hou <houzj.fnst@fujitsu.com>
Discussion: https://postgr.es/m/202411281216.sutbxtr6idnn@alvherre.pgsql
Stuff like
CREATE DOMAIN foo AS int CONSTRAINT cc GENERATED ALWAYS AS (2) STORED
is not supported for domains, but the parser allows it, because it's
the same syntax as for table constraints. But CreateDomain() did not
explicitly handle all ConstrType values, so the above would get an
internal error like
ERROR: unrecognized constraint subtype: 4
Fix that by providing a user-facing error message for all ConstrType
values. Also, remove the switch default case, so future additions to
ConstrType are caught.
Reported-by: Jian He <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/CACJufxF8fmM=Dbm4pDFuV_nKGz2-No0k4YifhrF3-rjXTWJM3w@mail.gmail.com
Commit 811af9786b introduced palloc() calls into systable_beginscan()
and systable_beginscan_ordered(). But there was no pfree(), as is the
usual style.
It turns out that an ANALYZE of a partitioned table can invoke many
thousand system table index scans, and this memory is not cleaned up
until the end of the command, so this can temporarily leak quite a bit
of memory. Maybe there are improvements to be made at a higher level
about this, but for now, insert a couple of corresponding pfree()
calls to fix this particular issue.
Reported-by: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://www.postgresql.org/message-id/Z0XTfIq5xUtbkiIh@pryzbyj2023
The new compact_attrs array stores a few select fields from
FormData_pg_attribute in a more compact way, using only 16 bytes per
column instead of the 104 bytes that FormData_pg_attribute uses. Using
CompactAttribute allows performance-critical operations such as tuple
deformation to be performed without looking at the FormData_pg_attribute
element in TupleDesc which means fewer cacheline accesses. With this
change, NAMEDATALEN could be increased with a much smaller negative impact
on performance.
For some workloads, tuple deformation can be the most CPU intensive part
of processing the query. Some testing with 16 columns on a table
where the first column is variable length showed around a 10% increase in
transactions per second for an OLAP type query performing aggregation on
the 16th column. However, in certain cases, the increases were much
higher, up to ~25% on one AMD Zen4 machine.
This also makes pg_attribute.attcacheoff redundant. A follow-on commit
will remove it, thus shrinking the FormData_pg_attribute struct by 4
bytes.
Author: David Rowley
Discussion: https://postgr.es/m/CAApHDvrBztXP3yx=NKNmo3xwFAFhEdyPnvrDg3=M0RhDs+4vYw@mail.gmail.com
Reviewed-by: Andres Freund, Victor Yegorov
Previously, it set only DELAY_CHKPT_COMPLETE. That was important,
because it meant that if the XLOG_SMGR_TRUNCATE record preceded a
XLOG_CHECKPOINT_ONLINE record in the WAL, then the truncation would also
happen on disk before the XLOG_CHECKPOINT_ONLINE record was
written.
However, it didn't guarantee that the sync request for the truncation
was processed before the XLOG_CHECKPOINT_ONLINE record was written. By
setting DELAY_CHKPT_START, we guarantee that if an XLOG_SMGR_TRUNCATE
record is written to WAL before the redo pointer of a concurrent
checkpoint, the sync request queued by that operation must be processed
by that checkpoint, rather than being left for the following one.
This is a refinement of commit 412ad7a556. Back-patch to all supported
releases, like that commit.
Author: Robert Haas <robertmhaas@gmail.com>
Reported-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKG%2B-2rjGZC2kwqr2NMLBcEBp4uf59QT1advbWYF_uc%2B0Aw%40mail.gmail.com
MD5 has been considered to be unsuitable for use as a cryptographic
hash algorithm for some time. Furthermore, MD5 password hashes in
PostgreSQL are vulnerable to pass-the-hash attacks, i.e., knowing
the username and hashed password is sufficient to authenticate.
The SCRAM-SHA-256 method added in v10 is not subject to these
problems and is considered to be superior to MD5.
This commit marks MD5 password support in PostgreSQL as deprecated
and to be removed in a future release. The documentation now
contains several deprecation notices, and CREATE ROLE and ALTER
ROLE now emit deprecation warnings when setting MD5 passwords. The
warnings can be disabled by setting the md5_password_warnings
parameter to "off".
Reviewed-by: Greg Sabino Mullane, Jim Nasby
Discussion: https://postgr.es/m/ZwbfpJJol7lDWajL%40nathan
According to the SQL standard, if the referential action RESTRICT is
triggered, it has its own error code. We previously didn't use that,
we just used the error code for foreign key violation. But RESTRICT
is not necessarily an actual foreign key violation. The foreign key
might still be satisfied in theory afterwards, but the RESTRICT
setting prevents the action even then. So it's a separate kind of
error condition.
Discussion: https://www.postgresql.org/message-id/ea5b2777-266a-46fa-852f-6fca6ec480ad@eisentraut.org
As I'd feared, commit 5c9d8636d was still a few bricks shy of a load.
We can't just leave pulled-up lateral-reference Vars with no new
nullingrels: we have to carefully compute what subset of the
to-be-replaced Var's nullingrels apply to them, else we still get
"wrong varnullingrels" errors. This is a bit tedious, but it looks
like we can use the nullingrel data this patch computes for other
purposes, enabling better optimization. We don't want to inject
unnecessary plan changes into stable branches though, so leave that
idea for a later HEAD-only patch.
Patch by me, but thanks to Richard Guo for devising a test case that
broke 5c9d8636d, and for preliminary investigation about how to fix
it. As before, back-patch to v16.
Discussion: https://postgr.es/m/E1tGn4j-0003zi-MP@gemulon.postgresql.org
Some lines were indented by an inconsistent number of spaces. While
we're here, also fix some code that used the newline after left
parenthesis style, which is obsolete.
There is no point in transforming OR-clauses into SAOP's if the target index
doesn't support SAOP scans anyway. This commit adds corresponding checks
to match_orclause_to_indexcol() and group_similar_or_args(). The first check
fixes the actual bug, while the second just saves some cycles.
Reported-by: Alexander Lakhin
Discussion: https://postgr.es/m/8174de69-9e1a-0827-0e81-ef97f56a5939%40gmail.com
Author: Alena Rybakina
Reviewed-by: Ranier Vilela, Alexander Korotkov, Andrei Lepikhov
If we are pulling up a subquery that's under an outer join, and
the subquery's target list contains a strict expression that uses
both a subquery variable and a lateral-reference variable, it's okay
to pull up the expression without wrapping it in a PlaceHolderVar.
That's safe because if the subquery variable is forced to NULL
by the outer join, the expression result will come out as NULL too,
so we don't have to force that outcome by evaluating the expression
below the outer join. It'd be correct to wrap in a PHV, but that can
lead to very significantly worse plans, since we'd then have to use
a nestloop plan to pass down the lateral reference to where the
expression will be evaluated.
However, when we do that, we should not mark the lateral reference
variable as being nulled by the outer join, because it isn't after
we pull up the expression in this way. So the marking logic added
by cb8e50a4a was incorrect in this detail, leading to "wrong
varnullingrels" errors from the consistency-checking logic in
setrefs.c. It seems to be sufficient to just not mark lateral
references at all in this case. (I have a nagging feeling that more
complexity may be needed in cases where there are several levels of
outer join, but some attempts to break it with that didn't succeed.)
Per report from Bertrand Mamasam. Back-patch to v16, as the previous
patch was.
Discussion: https://postgr.es/m/CACZ67_UA_EVrqiFXJu9XK50baEpH=ofEPJswa2kFxg6xuSw-ww@mail.gmail.com
The C standard says that sizeof(bool) is implementation-defined, but we
know of no current systems where it is not 1. The last known systems
seem to have been Apple macOS/PowerPC 10.5 and Microsoft Visual C++ 4,
both long defunct.
PostgreSQL has always required sizeof(bool) == 1 for the definition of
bool that it used, but previously it would define its own type if the
system-provided bool had a different size. That was liable to cause
memory layout problems when interacting with system and third-party
libraries on (by now hypothetical) computers with wider _Bool, and now
C23 has introduced a new problem by making bool a built-in datatype
(like C++), so the fallback code doesn't even compile. We could
probably work around that, but then we'd be writing new untested code
for a computer that doesn't exist.
Instead, delete the unreachable and C23-uncompilable fallback code, and
let existing static assertions fail if the system-provided bool is too
wide. If we ever get a problem report from a real system, then it will
be time to figure out what to do about it in a way that also works on
modern compilers.
Note on C++: Previously we avoided including <stdbool.h> or trying to
define a new bool type in headers that might be included by C++ code.
These days we might as well just include <stdbool.h> unconditionally:
it should be visible to C++11 but do nothing, just as in C23. We
already include <stdint.h> without C++ guards in c.h, and that falls
under the same C99-compatibility section of the C++11 standard as
<stdbool.h>, so let's remove the guards here too.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/3198438.1731895163%40sss.pgh.pa.us
They were all missing punctuation, one was missing initial capital.
Per our message style guidelines.
No backpatch, to avoid breaking existing translations.
Commit ccd38024bc, which introduced the pg_signal_autovacuum_worker
role, added a call to pgstat_get_beentry_by_proc_number() for the
purpose of determining whether the process is an autovacuum worker.
This function calls pgstat_read_current_status(), which can be
fairly expensive and may return cached, out-of-date information.
Since we just need to look up the target backend's BackendType, and
we already know its ProcNumber, we can instead inspect the
BackendStatusArray directly, which is much less expensive and
possibly more up-to-date. There are some caveats with this
approach (which are documented in the code), but it's still
substantially better than before.
Reported-by: Andres Freund
Reviewed-by: Andres Freund
Discussion: https://postgr.es/m/ujenaa2uabzfkwxwmfifawzdozh3ljr7geozlhftsuosgm7n7q%40g3utqqyyosb6
Emitting each variable separately is unnecessarily verbose / hard to skim
over. Emit the whole thing in one ereport() to address that.
Also remove program name and function reference from the message. The former
doesn't seem particularly helpful and the latter is provided by the elog.c
infrastructure these days.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/leouteo5ozcrux3fepuhtbp6c56tbfd4naxeokidbx7m75cabz@hhw6g4urlowt
Historically we tolerated the absence of various C runtime library
features for the benefit of the MinGW tool chain, because it used
ancient msvcrt.dll for a long period of time. It now uses ucrt by
default (like Windows 10+, Visual Studio 2015+), and that's the only
configuration we're testing.
In practice, we effectively required ucrt already in PostgreSQL 17, when
commit 8d9a9f03 required _create_locale etc, first available in
msvcr120.dll (Visual Studio 2013, the last of the pre-ucrt series of
runtimes), and for MinGW users that practically meant ucrt because it
was difficult or impossible to use msvcr120.dll. That may even not have
been the first such case, but old MinGW configurations had already
dropped off our testing radar so we weren't paying much attention.
This commit formalizes the requirement. It also removes a couple of
obsolete comments that discussed msvcrt.dll limitations, and some tests
of !defined(_MSC_VER) to imply msvcrt.dll. There are many more
anachronisms, but it'll take some time to figure out how to remove them
all. APIs affected relate to locales, UTF-8, threads, large files and
more.
Thanks to Peter Eisentraut for the documentation change. It's not
really necessary to talk about ucrt explicitly in such a short section,
since it's the default for MinGW-w64 and MSYS2. It's enough to prune
references and broken links to much older tools.
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/d9e7731c-ca1b-477c-9298-fa51e135574a%40eisentraut.org
This allows for example using LIKE with case-insensitive collations.
There was previously no internal implementation of this, so it was met
with a not-supported error. This adds the internal implementation and
removes the error. The implementation follows the specification of
the SQL standard for this.
Unlike with deterministic collations, the LIKE matching cannot go
character by character but has to go substring by substring. For
example, if we are matching against LIKE 'foo%bar', we can't start by
looking for an 'f', then an 'o', but instead with have to find
something that matches 'foo'. This is because the collation could
consider substrings of different lengths to be equal. This is all
internal to MatchText() in like_match.c.
The changes in GenericMatchText() in like.c just pass through the
locale information to MatchText(), which was previously not needed.
This matches exactly Generic_Text_IC_like() below.
ILIKE is not affected. (It's unclear whether ILIKE makes sense under
nondeterministic collations.)
This also updates match_pattern_prefix() in like_support.c to support
optimizing the case of an exact pattern with nondeterministic
collations. This was already alluded to in the previous code.
(includes documentation examples from Daniel Vérité and test cases
from Paul A Jungwirth)
Reviewed-by: Jian He <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/700d2e86-bf75-4607-9cf2-f5b7802f6e88@eisentraut.org
Currently, logical replication produces a generic error message when
targeting a subscriber-side table column that is either missing or
generated. The error message can be misleading for generated columns.
This patch introduces a specific error message to clarify the issue when
generated columns are involved.
Author: Shubham Khanna
Reviewed-by: Peter Smith, Vignesh C, Amit Kapila
Discussion: https://postgr.es/m/CAHv8RjJBvYtqU7OAofBizOmQOK2Q8h+w9v2_cQWxT_gO7er3Aw@mail.gmail.com
When using a pipeline, a transaction starts from the first command and
is committed with a Sync message or when the pipeline ends.
Functions like IsInTransactionBlock() or PreventInTransactionBlock()
were already able to understand a pipeline as being in a transaction
block, but it was not the case of CheckTransactionBlock(). This
function is called for example to generate a WARNING for SET LOCAL,
complaining that it is used outside of a transaction block.
The current state of the code caused multiple problems, like:
- SET LOCAL executed at any stage of a pipeline issued a WARNING, even
if the command was at least second in line where the pipeline is in a
transaction state.
- LOCK TABLE failed when invoked at any step of a pipeline, even if it
should be able to work within a transaction block.
The pipeline protocol assumes that the first command of a pipeline is
not part of a transaction block, and that any follow-up commands is
considered as within a transaction block.
This commit changes the backend so as an implicit transaction block is
started each time the first Execute message of a pipeline has finished
processing, with this implicit transaction block ended once a sync is
processed. The checks based on XACT_FLAGS_PIPELINING in the routines
checking if we are in a transaction block are not necessary: it is
enough to rely on the existing ones.
Some tests are added to pgbench, that can be backpatched down to v17
when \syncpipeline is involved and down to v14 where \startpipeline and
\endpipeline are available. This is unfortunately limited regarding the
error patterns that can be checked, but it provides coverage for various
pipeline combinations to check if these succeed or fail. These tests
are able to capture the case of SET LOCAL's WARNING. The author has
proposed a different feature to improve the coverage by adding similar
meta-commands to psql where error messages could be checked, something
more useful for the cases where commands cannot be used in transaction
blocks, like REINDEX CONCURRENTLY or VACUUM. This is considered as
future work for v18~.
Author: Anthonin Bonnefoy
Reviewed-by: Jelte Fennema-Nio, Michael Paquier
Discussion: https://postgr.es/m/CAO6_XqrWO8uNBQrSu5r6jh+vTGi5Oiyk4y8yXDORdE2jbzw8xw@mail.gmail.com
Backpatch-through: 13
The error messages in CreateWaitEventSet() made it hard to know whether the
syscall or AcquireExternalFD() failed. This is particularly relevant because
AcquireExternalFD() imposes a lower limit than what would cause syscalls fail
with EMFILE.
I did not change the message in libpqsrv_connect_prepare(), which is the one
other use of AcquireExternalFD() in our codebase, as the error message already
is less ambiguous.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/xjjx7r4xa7beixuu4qtkdhnwdbchrrpo3gaeb3jsbinvvdiat5@cwjw55mna5of
Most came in during the 17 cycle, so backpatch there. Some
(particularly reorderbuffer.h) are very old, but backpatching doesn't
seem useful.
Like commits c9d2977519, c4f113e8fe.
The function get_param_path_clause_serials() is used to get the set of
pushed-down clauses enforced within a parameterized Path. Since we
don't currently support parameterized MergeAppend paths, and it
doesn't look like that is going to change anytime soon (as explained
in the comments for generate_orderedappend_paths), we don't need to
consider MergeAppendPath in this function.
This change won't make any measurable difference in performance; it's
just for clarity's sake.
Author: Richard Guo
Reviewed-by: Andrei Lepikhov
Discussion: https://postgr.es/m/CAMbWs4_Puie4DQ2ODvjQB_3CxYkUODnrJm8jn_ObMAcrjYNW7Q@mail.gmail.com
The ordering of DISTINCT items is semantically insignificant, so we
can reorder them as needed. In fact, in the parser, we absorb the
sorting semantics of the sortClause as much as possible into the
distinctClause, ensuring that one clause is a prefix of the other.
This can help avoid a possible need to re-sort.
In this commit, we attempt to adjust the DISTINCT keys to match the
input path's pathkeys. This can likewise help avoid re-sorting, or
allow us to use incremental-sort to save efforts.
For DISTINCT ON expressions, the parser already ensures that they
match the initial ORDER BY expressions. When reordering the DISTINCT
keys, we must ensure that the resulting pathkey list matches the
initial distinctClause pathkeys.
This introduces a new GUC, enable_distinct_reordering, which allows
the optimization to be disabled if needed.
Author: Richard Guo
Reviewed-by: Andrei Lepikhov
Discussion: https://postgr.es/m/CAMbWs48dR26cCcX0f=8bja2JKQPcU64136kHk=xekHT9xschiQ@mail.gmail.com
If passed a read-write expanded object pointer, the EEOP_NULLIF
code would hand that same pointer to the equality function
and then (unless equality was reported) also return the same
pointer as its value. This is no good, because a function that
receives a read-write expanded object pointer is fully entitled
to scribble on or even delete the object, thus corrupting the
NULLIF output. (This problem is likely unobservable with the
equality functions provided in core Postgres, but it's easy to
demonstrate with one coded in plpgsql.)
To fix, make sure the pointer passed to the equality function
is read-only. We can still return the original read-write
pointer as the NULLIF result, allowing optimization of later
operations.
Per bug #18722 from Alexander Lakhin. This has been wrong
since we invented expanded objects, so back-patch to all
supported branches.
Discussion: https://postgr.es/m/18722-fd9e645448cc78b4@postgresql.org
This WARNING appeared because SearchSysCacheLocked1() read
cc_relisshared before catcache initialization, when the field is false
unconditionally. On the basis of reading false there, it constructed a
locktag as though pg_tablespace weren't relisshared. Only shared
catalogs could be affected, and only GRANT TABLESPACE was affected in
practice. SearchSysCacheLocked1() callers use one other shared-relation
syscache, DATABASEOID. DATABASEOID is initialized by the end of
CheckMyDatabase(), making the problem unreachable for pg_database.
Back-patch to v13 (all supported versions). This has no known impact
before v16, where ExecGrant_common() first appeared. Earlier branches
avoid trouble by having a separate ExecGrant_Tablespace() that doesn't
use LOCKTAG_TUPLE. However, leaving this unfixed in v15 could ensnare a
future back-patch of a SearchSysCacheLocked1() call.
Reported by Aya Iwata.
Discussion: https://postgr.es/m/OS7PR01MB11964507B5548245A7EE54E70EA212@OS7PR01MB11964.jpnprd01.prod.outlook.com
When optimizer generates bitmap paths, it considers breaking OR-clause
arguments one-by-one. But now, a group of similar OR-clauses can be
transformed into SAOP during index matching. So, bitmap paths should
keep up.
This commit teaches bitmap paths generation machinery to group similar
OR-clauses into dedicated RestrictInfos. Those RestrictInfos are considered
both to match index as a whole (as SAOP), or to match as a set of individual
OR-clause argument one-by-one (the old way).
Therefore, bitmap path generation will takes advantage of OR-clauses to SAOP's
transformation. The old way of handling them is also considered. So, there
shouldn't be planning regression.
Discussion: https://postgr.es/m/CAPpHfdu5iQOjF93vGbjidsQkhHvY2NSm29duENYH_cbhC6x%2BMg%40mail.gmail.com
Author: Alexander Korotkov, Andrey Lepikhov
Reviewed-by: Alena Rybakina, Andrei Lepikhov, Jian he, Robert Haas
Reviewed-by: Peter Geoghegan
This commit makes match_clause_to_indexcol() match
"(indexkey op C1) OR (indexkey op C2) ... (indexkey op CN)" expression
to the index while transforming it into "indexkey op ANY(ARRAY[C1, C2, ...])"
(ScalarArrayOpExpr node).
This transformation allows handling long OR-clauses with single IndexScan
avoiding diving them into a slower BitmapOr.
We currently restrict Ci to be either Const or Param to apply this
transformation only when it's clearly beneficial. However, in the future,
we might switch to a liberal understanding of constants, as it is in other
cases.
Discussion: https://postgr.es/m/567ED6CA.2040504%40sigaev.ru
Author: Alena Rybakina, Andrey Lepikhov, Alexander Korotkov
Reviewed-by: Peter Geoghegan, Ranier Vilela, Alexander Korotkov, Robert Haas
Reviewed-by: Jian He, Tom Lane, Nikolay Shaplov
Like INT64_FORMAT and UINT64_FORMAT, these macros produce format
strings for 64-bit integers. However, INT64_HEX_FORMAT and
UINT64_HEX_FORMAT generate the output in hexadecimal instead of
decimal. Besides introducing these macros, this commit makes use
of them in several places. This was originally intended to be part
of commit 5d6187d2a2, but I left it out because I felt there was a
nonzero chance that back-patching these new macros into c.h could
cause problems with third-party code. We tend to be less cautious
with such changes in new major versions.
Note that UINT64_HEX_FORMAT was originally added in commit
ee1b30f128, but it was placed in test_radixtree.c, so it wasn't
widely available. This commit moves UINT64_HEX_FORMAT to c.h.
Discussion: https://postgr.es/m/ZwQvtUbPKaaRQezd%40nathan
If a user started a bulk write operation on a fork with existing data
to append data in bulk, the bulk_write machinery would zero out all
previously written pages up to the last page written by the new
bulk_write operation.
This is not an issue for PostgreSQL itself, because we never use the
bulk_write facility on a non-empty fork. But there are use cases where
it makes sense. TimescaleDB extension is known to do that to merge
partitions, for example.
Backpatch to v17, where the bulk_write machinery was introduced.
Author: Matthias van de Meent <boekewurm+postgres@gmail.com>
Reported-By: Erik Nordström <erik@timescale.com>
Reviewed-by: Erik Nordström <erik@timescale.com>
Discussion: https://www.postgresql.org/message-id/CACAa4VJ%2BQY4pY7M0ECq29uGkrOygikYtao1UG9yCDFosxaps9g@mail.gmail.com
This new field controls if entries of a stats kind should be written or
not to the on-disk pgstats file when shutting down an instance. This
affects both fixed and variable-numbered kinds.
This is useful for custom statistics by itself, and a patch is under
discussion to add a new builtin stats kind where the write of the stats
is not necessary. All the built-in stats kinds, as well as the two
custom stats kinds in the test module injection_points, set this flag to
"true" for now, so as stats entries are written to the on-disk pgstats
file.
Author: Bertrand Drouvot
Reviewed-by: Nazir Bilal Yavuz
Discussion: https://postgr.es/m/Zz7T47nHwYgeYwOe@ip-10-97-1-34.eu-west-3.compute.internal
Apparently this information has been outdated since first committed,
because we adopted a different implementation during development per
reviews and this detail was not updated in the README.
This has been wrong since commit 0ac5ad5134 introduced the file in
2013. Backpatch to all live branches.
Reported-by: Will Mortensen <will@extrahop.com>
Discussion: https://postgr.es/m/CAMpnoC6yEQ=c0Rdq-J7uRedrP7Zo9UMp6VZyP23QMT68n06cvA@mail.gmail.com
RelationSyncCache, the hash table in charge of tracking the relation
schemas sent through pgoutput, was forgetting to free the TupleDesc
associated to the two slots used to store the new and old tuples,
causing some memory to be leaked each time a relation is invalidated
when the slots of an existing relation entry are cleaned up.
This is rather hard to notice as the bloat is pretty minimal, but a
long-running WAL sender would be in trouble over time depending on the
workload. sysbench has proved to be pretty good at showing the problem,
coupled with some memory monitoring of the WAL sender.
Issue introduced in 52e4f0cd47, that has added row filters for tables
logically replicated.
Author: Boyu Yang
Reviewed-by: Michael Paquier, Hou Zhijie
Discussion: https://postgr.es/m/DM3PR84MB3442E14B340E553313B5C816E3252@DM3PR84MB3442.NAMPRD84.PROD.OUTLOOK.COM
Backpatch-through: 15
Spell out how a = key associated with a SAOP array renders a > key
against the same index column redundant at the relevant point inside
_bt_preprocess_keys.
Follow-up to commit 5bf748b8.
Ordinarily transformSetOperationTree will collect all UNION/
INTERSECT/EXCEPT steps into the setOperations tree of the topmost
Query, so that leaf queries do not contain any setOperations.
However, it cannot thus flatten a subquery that also contains
WITH, ORDER BY, FOR UPDATE, or LIMIT. I (tgl) forgot that in
commit 07b4c48b6 and wrote an assertion in rule deparsing that
a leaf's setOperations would always be empty.
If it were nonempty then we would want to parenthesize the subquery
to ensure that the output represents the setop nesting correctly
(e.g. UNION below INTERSECT had better get parenthesized). So
rather than just removing the faulty Assert, let's change it into
an additional case to check to decide whether to add parens. We
don't expect that the additional case will ever fire, but it's
cheap insurance.
Man Zeng and Tom Lane
Discussion: https://postgr.es/m/tencent_7ABF9B1F23B0C77606FC5FE3@qq.com
Commit 4ac2a9bece introduced the REJECT_LIMIT option for the COPY
command. This commit extends the support for this option to file_fdw.
As well as REJECT_LIMIT option for COPY, this option limits
the maximum number of erroneous rows that can be skipped.
If the number of data type conversion errors exceeds this limit,
accessing the file_fdw foreign table will fail with an error,
even when on_error = 'ignore' is specified.
Since the CREATE/ALTER FOREIGN TABLE commands require foreign
table options to be single-quoted, this commit updates
defGetCopyRejectLimitOption() to handle also string value for them,
in addition to int64 value for COPY command option.
Author: Atsushi Torikoshi
Reviewed-by: Fujii Masao, Yugo Nagata, Kirill Reshke
Discussion: https://postgr.es/m/bab68a9fc502b12693f0755b6f35f327@oss.nttdata.com
In the dim past we figured it was okay to ignore collations
when combining UNION set-operation nodes into a single N-way
UNION operation. I believe that was fine at the time, but
it stopped being fine when we added nondeterministic collations:
the semantics of distinct-ness are affected by those. v17 made
it even less fine by allowing per-child sorting operations to
be merged via MergeAppend, although I think we accidentally
avoided any live bug from that.
Add a check that collations match before deciding that two
UNION nodes are equivalent. I also failed to resist the
temptation to comment plan_union_children() a little better.
Back-patch to all supported branches (v13 now), since they
all have nondeterministic collations.
Discussion: https://postgr.es/m/3605568.1731970579@sss.pgh.pa.us
Previously, database object statistics manipulation functions like
pg_set_relation_stats() reported unclear error and hint messages
when executed during recovery. These messages were "internal",
making it difficult for users to understand the issue:
ERROR: cannot acquire lock mode ShareUpdateExclusiveLock on database objects while recovery is in progress
HINT: Only RowExclusiveLock or less can be acquired on database objects during recovery.
This commit updates the error handling so that, if these functions
are called during recovery, they produce clearer messages:
ERROR: recovery is in progress
HINT: Statistics cannot be modified during recovery.
The related documentation has also been updated to explicitly
clarify that these functions are not available during recovery.
Author: Fujii Masao
Reviewed-by: Heikki Linnakangas, Maxim Orlov
Discussion: https://postgr.es/m/6d313829-5f56-4a28-ae4b-bd01bf1ae791@oss.nttdata.com
Relying on pg_memory_is_all_zeros(), which would apply SIMD instructions
when dealing with an aligned page, is proving to be at least three times
faster than the original size_t-based comparisons when checking if a
BLCKSZ page is full of zeros. Note that PageIsVerifiedExtended() is
called each time a page is read from disk, and making it faster is a
good thing.
Author: Bertrand Drouvot
Discussion: https://postgr.es/m/CAApHDvq7P-JgFhgtxUPqhavG-qSDVUhyWaEX9M8_MNorFEijZA@mail.gmail.com
After commit 5a2fed911a, the catalog state
resulting from these commands ceased to affect sessions. Restore the
longstanding behavior, which is like beginning the session with a SET
ROLE command. If cherry-picking the CVE-2024-10978 fixes, default to
including this, too. (This fixes an unintended side effect of fixing
CVE-2024-10978.) Back-patch to v12, like that commit. The release team
decided to include v12, despite the original intent to halt v12 commits
earlier this week.
Tom Lane and Noah Misch. Reported by Etienne LAFARGE.
Discussion: https://postgr.es/m/CADOZwSb0UsEr4_UTFXC5k7=fyyK8uKXekucd+-uuGjJsGBfxgw@mail.gmail.com
Previously LogicalIncreaseRestartDecodingForSlot() accidentally
accepted any LSN as the candidate_lsn and candidate_valid after the
restart_lsn of the replication slot was updated, so it potentially
caused the restart_lsn to move backwards.
A scenario where this could happen in logical replication is: after a
logical replication restart, based on previous candidate_lsn and
candidate_valid values in memory, the restart_lsn advances upon
receiving a subscriber acknowledgment. Then, logical decoding restarts
from an older point, setting candidate_lsn and candidate_valid based
on an old RUNNING_XACTS record. Subsequent subscriber acknowledgments
then update the restart_lsn to an LSN older than the current value.
In the reported case, after WAL files were removed by a checkpoint,
the retreated restart_lsn prevented logical replication from
restarting due to missing WAL segments.
This change essentially modifies the 'if' condition to 'else if'
condition within the function. The previous code had an asymmetry in
this regard compared to LogicalIncreaseXminForSlot(), which does
almost the same thing for different fields.
The WAL removal issue was reported by Hubert Depesz Lubaczewski.
Backpatch to all supported versions, since the bug exists since 9.4
where logical decoding was introduced.
Reviewed-by: Tomas Vondra, Ashutosh Bapat, Amit Kapila
Discussion: https://postgr.es/m/Yz2hivgyjS1RfMKs%40depesz.com
Discussion: https://postgr.es/m/85fff40e-148b-4e86-b921-b4b846289132%40vondra.me
Backpatch-through: 13
In commit 08c0d6ad6 which introduced "rainbow" arcs in regex NFAs,
I didn't think terribly hard about what to do when creating the color
complement of a rainbow arc. Clearly, the complement cannot match any
characters, and I took the easy way out by just not building any arcs
at all in the complement arc set. That mostly works, but Nikolay
Shaplov found a case where it doesn't: if we decide to delete that
sub-NFA later because it's inside a "{0}" quantifier, delsub()
suffered an assertion failure. That's because delsub() relies on
the target sub-NFA being fully connected. That was always true
before, and the best fix seems to be to restore that property.
Hence, invent a new arc type CANTMATCH that can be generated in
place of an empty color complement, and drop it again later when we
start NFA optimization. (At that point we don't need to do delsub()
any more, and besides there are other cases where NFA optimization can
lead to disconnected subgraphs.)
It appears that this bug has no consequences in a non-assert-enabled
build: there will be some transiently leaked NFA states/arcs, but
they'll get cleaned up eventually. Still, we don't like assertion
failures, so back-patch to v14 where rainbow arcs were introduced.
Per bug #18708 from Nikolay Shaplov.
Discussion: https://postgr.es/m/18708-f94f2599c9d2c005@postgresql.org
Allowing foreign keys where the referenced and the referencing columns
have collations with different notions of equality is problematic.
This can only happen when using nondeterministic collations, for
example, if the referencing column is case-insensitive and the
referenced column is not, or vice versa. It does not happen if both
collations are deterministic.
To show one example:
CREATE COLLATION case_insensitive (provider = icu, deterministic = false, locale = 'und-u-ks-level2');
CREATE TABLE pktable (x text COLLATE "C" PRIMARY KEY);
CREATE TABLE fktable (x text COLLATE case_insensitive REFERENCES pktable ON UPDATE CASCADE ON DELETE CASCADE);
INSERT INTO pktable VALUES ('A'), ('a');
INSERT INTO fktable VALUES ('A');
BEGIN; DELETE FROM pktable WHERE x = 'a'; TABLE fktable; ROLLBACK;
BEGIN; DELETE FROM pktable WHERE x = 'A'; TABLE fktable; ROLLBACK;
Both of these DELETE statements delete the one row from fktable. So
this means that one row from fktable references two rows in pktable,
which should not happen. (That's why a primary key or unique
constraint is required on pktable.)
When nondeterministic collations were implemented, the SQL standard
available to yours truly said that referential integrity checks should
be performed with the collation of the referenced column, and so
that's how we implemented it. But this turned out to be a mistake in
the SQL standard, for the same reasons as above, that was later
(SQL:2016) fixed to require both collations to be the same. So that's
what we are aiming for here.
We don't have to be quite so strict. We can allow different
collations if they are both deterministic. This is also good for
backward compatibility.
So the new rule is that the collations either have to be the same or
both deterministic. Or in other words, if one of them is
nondeterministic, then both have to be the same.
Users upgrading from before that have affected setups will need to
make changes to their schemas (i.e., change one or both collations in
affected foreign-key relationships) before the upgrade will succeed.
Some of the nice test cases for the previous situation in
collate.icu.utf8.sql are now obsolete. They are changed to just check
the error checking of the new rule. Note that collate.sql already
contained a test for foreign keys with different deterministic
collations.
A bunch of code in ri_triggers.c that added a COLLATE clause to
enforce the referenced column's collation can be removed, because both
columns now have to have the same notion of equality, so it doesn't
matter which one to use.
Reported-by: Paul Jungwirth <pj@illuminatedcomputing.com>
Reviewed-by: Jian He <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/78d824e0-b21e-480d-a252-e4b84bc2c24b@illuminatedcomputing.com
Refactor objectNamesToOids() to use get_object_address() internally if
possible. Not only does this save a lot of code, it also allows us to
use the object locking provided by get_object_address() for
GRANT/REVOKE. There was previously a code comment that complained
about the lack of locking in objectNamesToOids(), which is now fixed.
The check in ExecGrant_Type_check() is obsolete because
get_object_address_type() already does the same check.
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/bf72b82c-124d-4efa-a484-bb928e9494e4@eisentraut.org
In EEOP_BOOL_AND_STEP* and EEOP_BOOL_OR_STEP*, we emitted pointlesss
store instructions to store to resnull/resvalue values that were just
loaded from the same fields in the previous instructions. They will
surely get optimized away by LLVM if any optimizations are enabled,
but it's better to not emit them in the first place. In
EEOP_BOOL_NOT_STEP, similar story with resnull.
In EEOP_NULLIF, when it returns NULL, there was also a redundant store
to resvalue just after storing a 0 to it. The value of resvalue
doesn't matter when resnull is set, so in fact even storing the 0 is
unnecessary, but I kept that because we tend to do that for general
tidiness.
Author: Xing Guo <higuoxing@gmail.com>
Reviewed-by: Andreas Karlsson <andreas@proxel.se>
Discussion: https://www.postgresql.org/message-id/CACpMh%2BC%3Dg13WdvzLRSponsVWGgxwDSMzQWM4Gz0heOyaA0-N6g@mail.gmail.com
Some places declared a Relation before calling get_object_address()
only to assert that the relation is NULL after the call.
The new assertion allows passing NULL as the relation argument at
those places making the code cleaner and easier to understand.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://www.postgresql.org/message-id/ZzG34eNrT83W/Orz@ip-10-97-1-34.eu-west-3.compute.internal
This fixes a set of race conditions with cumulative statistics where a
shared stats entry could be dropped while it should still be valid in
the event when it is reused: an entry may refer to a different object
but requires the same hash key. This can happen with various stats
kinds, like:
- Replication slots that compute internally an index number, for
different slot names.
- Stats kinds that use an OID in the object key, where a wraparound
causes the same key to be used if an OID is used for the same object.
- As of PostgreSQL 18, custom pgstats kinds could also be an issue,
depending on their implementation.
This issue is fixed by introducing a counter called "generation" in the
shared entries via PgStatShared_HashEntry, initialized at 0 when an
entry is created and incremented when the same entry is reused, to avoid
concurrent issues on drop because of other backends still holding a
reference to it. This "generation" is copied to the local copy that a
backend holds when looking at an object, then cross-checked with the
shared entry to make sure that the entry is not dropped even if its
"refcount" justifies that if it has been reused.
This problem could show up when a backend shuts down and needs to
discard any entries it still holds, causing statistics to be removed
when they should not, or even an assertion failure. Another report
involved a failure in a standby after an OID wraparound, where the
startup process would FATAL on a "can only drop stats once", stopping
recovery abruptly. The buildfarm has been sporadically complaining
about the problem, as well, but the window is hard to reach with the
in-core tests.
Note that the issue can be reproduced easily by adding a sleep before
dshash_find() in pgstat_release_entry_ref() to enlarge the problematic
window while repeating test_decoding's isolation test oldest_xmin a
couple of times, for example, as pointed out by Alexander Lakhin.
Reported-by: Alexander Lakhin, Peter Smith
Author: Kyotaro Horiguchi, Michael Paquier
Reviewed-by: Bertrand Drouvot
Discussion: https://postgr.es/m/CAA4eK1KxuMVyAryz_Vk5yq3ejgKYcL6F45Hj9ZnMNBS-g+PuZg@mail.gmail.com
Discussion: https://postgr.es/m/17947-b9554521ad963c9c@postgresql.org
Backpatch-through: 15
Previously, only backends, autovacuum workers, and background workers
had an entry in the PMChildFlags array. With this commit, all
postmaster child processes, including all the aux processes, have an
entry. Dead-end backends still don't get an entry, though, and other
processes that don't touch shared memory will never mark their
PMChildFlags entry as active.
We now maintain separate freelists for different kinds of child
processes. That ensures that there are always slots available for
autovacuum and background workers. Previously, pre-authentication
backends could prevent autovacuum or background workers from starting
up, by using up all the slots.
The code to manage the slots in the postmaster process is in a new
pmchild.c source file. Because postmaster.c is just so large.
Assigning pmsignal slot numbers is now pmchild.c's responsibility.
This replaces the PMChildInUse array in pmsignal.c.
Some of the comments in postmaster.c still talked about the "stats
process", but that was removed in commit 5891c7a8ed. Fix those while
we're at it.
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/a102f15f-eac4-4ff2-af02-f9ff209ec66f@iki.fi
Previously, the postmaster would never try to kill dead-end child
processes, even if there were no other processes left. A dead-end
backend will eventually exit, when authentication_timeout expires, but
if a dead-end backend is the only thing that's preventing the server
from shutting down, it seems better to kill it immediately. It's
particularly important, if there was a bug in the early startup code
that prevented a dead-end child from timing out and exiting normally.
Includes a test for that case where a dead-end backend previously
prevented the server from shutting down.
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/a102f15f-eac4-4ff2-af02-f9ff209ec66f@iki.fi
This makes it easier to add precondition assertions. We now assert that
the last call to _bt_readpage succeeded, and that the current item index
is within the bounds of the currPos items array.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Masahiro Ikeda <ikedamsh@oss.nttdata.com>
Discussion: https://postgr.es/m/CAH2-WznFkEs9K1PtNruti5JjawY-dwj+gkaEh_k1ZE+1xLLGkA@mail.gmail.com
InjectionPointEntry->name was described as a hash key, which was fine
when introduced in d86d20f0ba, but it is not now.
Oversight in 86db52a506, that has changed the way injection points are
stored in shared memory from a hash table to an array.
Backpatch-through: 17
Multiple buildfarm animals warn that a newly added Assert() is
impossible to fail; remove it to avoid the noise. While at it, use
direct assignment to obtain the value we need, avoiding an unnecessary
memcpy().
(I decided to remove the "pfree" call for the detoasted short-datum;
because this is only used for DDL, it's not problematic to leak such a
small allocation.)
Noted by Tom Lane about 14e87ffa5c.
Discussion: https://postgr.es/m/3649828.1731083171@sss.pgh.pa.us
The current code calls array_eq() and does not provide FmgrInfo. This commit
provides initialization of FmgrInfo and uses C collation as the safe option
for text comparison because we don't know anything about the semantics of
opclass options.
Backpatch to 13, where opclass options were introduced.
Reported-by: Nicolas Maus
Discussion: https://postgr.es/m/18692-72ea398df3ec6712%40postgresql.org
Backpatch-through: 13
Commit 5a2fed911 had an unexpected side-effect: the parallel worker
launched for the new test case would fail if it couldn't use a
superuser-reserved connection slot. The reason that test failed
while all our pre-existing ones worked is that the connection
privilege tests in InitPostgres had been based on the superuserness
of the leader's AuthenticatedUserId, but after the rearrangements
of 5a2fed911 we were testing the superuserness of CurrentUserId,
which the new test case deliberately made to be a non-superuser.
This all seems very accidental and probably not the behavior we really
want, but a security patch is no time to be redesigning things.
Pending some discussion about desirable semantics, hack it so that
InitPostgres continues to pay attention to the superuserness of
AuthenticatedUserId when starting a parallel worker.
Nathan Bossart and Tom Lane, per buildfarm member sawshark.
Security: CVE-2024-10978
The SQL spec mandates that SET SESSION AUTHORIZATION implies
SET ROLE NONE. We tried to implement that within the lowest-level
functions that manipulate these settings, but that was a bad idea.
In particular, guc.c assumes that it doesn't matter in what order
it applies GUC variable updates, but that was not the case for these
two variables. This problem, compounded by some hackish attempts to
work around it, led to some security-grade issues:
* Rolling back a transaction that had done SET SESSION AUTHORIZATION
would revert to SET ROLE NONE, even if that had not been the previous
state, so that the effective user ID might now be different from what
it had been.
* The same for SET SESSION AUTHORIZATION in a function SET clause.
* If a parallel worker inspected current_setting('role'), it saw
"none" even when it should see something else.
Also, although the parallel worker startup code intended to cope
with the current role's pg_authid row having disappeared, its
implementation of that was incomplete so it would still fail.
Fix by fully separating the miscinit.c functions that assign
session_authorization from those that assign role. To implement the
spec's requirement, teach set_config_option itself to perform "SET
ROLE NONE" when it sets session_authorization. (This is undoubtedly
ugly, but the alternatives seem worse. In particular, there's no way
to do it within assign_session_authorization without incompatible
changes in the API for GUC assign hooks.) Also, improve
ParallelWorkerMain to directly set all the relevant user-ID variables
instead of relying on some of them to get set indirectly. That
allows us to survive not finding the pg_authid row during worker
startup.
In v16 and earlier, this includes back-patching 9987a7bf3 which
fixed a violation of GUC coding rules: SetSessionAuthorization
is not an appropriate place to be throwing errors from.
Security: CVE-2024-10978
If a CTE, subquery, sublink, security invoker view, or coercion
projection references a table with row-level security policies, we
neglected to mark the plan as potentially dependent on which role
is executing it. This could lead to later executions in the same
session returning or hiding rows that should have been hidden or
returned instead.
Reported-by: Wolfgang Walther
Reviewed-by: Noah Misch
Security: CVE-2024-10976
Backpatch-through: 12
Two attributes are added to pg_stat_database:
* parallel_workers_to_launch, counting the total number of parallel
workers that were planned to be launched.
* parallel_workers_launched, counting the total number of parallel
workers actually launched.
The ratio of both fields can provide hints that there are not enough
slots available when launching parallel workers, also useful when
pg_stat_statements is not deployed on an instance (i.e. cf54a2c002).
This commit relies on de3a2ea3b2, that has added two fields to EState,
that get incremented when executing Gather or GatherMerge nodes.
A test is added in select_parallel, where parallel workers are spawned.
Bump catalog version.
Author: Benoit Lobréau
Discussion: https://postgr.es/m/783bc7f7-659a-42fa-99dd-ee0565644e25@dalibo.com
When _bt_readnextpage is called with our nbtree parallel scan already
seized (i.e. when it is directly called by _bt_first), we never expect a
prior call to _bt_readpage for lastcurrblkno to already indicate that
the scan should end -- the _bt_first caller's blkno must always be read.
After all, the "prior" _bt_readpage call (the call for lastcurrblkno)
probably took place in some other backend (and it might not even have
finished by the time our backend reaches _bt_first/_bt_readnextpage).
Add a documenting assertion to the path where _bt_readnextpage ends the
parallel scan based on information about lastcurrblkno from so->currPos.
Assert that the most recent _bt_readpage call that set so->currPos is in
fact lastcurrblkno's _bt_readpage call.
Follow-up to bugfix commit b5ee4e52.
Commit ac04aa84a put the shutoff for this into the planner, which is
not ideal because it doesn't prevent us from re-using a previously
made parallel plan. Revert the planner change and instead put the
shutoff into InitializeParallelDSM, modeling it on the existing code
there for recovering from failure to allocate a DSM segment.
However, that code path is mostly untested, and testing a bit harder
showed there's at least one bug: ExecHashJoinReInitializeDSM is not
prepared for us to have skipped doing parallel DSM setup. I also
thought the Assert in ReinitializeParallelWorkers is pretty
ill-advised, and replaced it with a silent Min() operation.
The existing test case added by ac04aa84a serves fine to test this
version of the fix, so no change needed there.
Patch by me, but thanks to Noah Misch for the core idea that we
could shut off worker creation when !INTERRUPTS_CAN_BE_PROCESSED.
Back-patch to v12, as ac04aa84a was.
Discussion: https://postgr.es/m/CAC-SaSzHUKT=vZJ8MPxYdC_URPfax+yoA1hKTcF4ROz_Q6z0_Q@mail.gmail.com
Commit 1bd4bc85, which refactored nbtree sibling link traversal, made
_bt_parallel_seize reset the scan's currPos so that things were
consistent with the state of a serial backend moving between pages.
This overlooked the fact that _bt_readnextpage relied on the existing
currPos state to decide when to end the scan -- even though it came from
before the scan was seized. As a result of all this, parallel nbtree
scans could needlessly behave like full index scans.
To fix, teach _bt_readnextpage to explicitly allow the use of an already
read page's so->currPos when deciding whether to end the scan -- even
during parallel index scans (allow it consistently now). This requires
moving _bt_readnextpage's seizure of the scan to earlier in its loop.
That way _bt_readnextpage either deals with the true so->currPos state,
or an initialized-by-_bt_parallel_seize currPos state set from when the
scan was seized. Now _bt_steppage (the most important _bt_readnextpage
caller) takes the same uniform approach to setting up its call using
details taken from so->currPos -- regardless of whether the scan happens
to be parallel or serial.
The new loop structure in _bt_readnextpage is prone to getting confused
by P_NONE blknos set when the rightmost or leftmost page was reached.
We could avoid that by adding an explicit check, but that would be ugly.
Avoid this problem by teaching _bt_parallel_seize to end the parallel
scan instead of returning a P_NONE next block/blkno. Doing things this
way was arguably a missed opportunity for commit 1bd4bc85. It allows us
to remove a similar "blkno == P_NONE" check from _bt_first.
Oversight in commit 1bd4bc85, which refactored sibling link traversal
(as part of optimizing nbtree backward scan locking).
Author: Peter Geoghegan <pg@bowt.ie>
Reported-By: Masahiro Ikeda <ikedamsh@oss.nttdata.com>
Diagnosed-By: Masahiro Ikeda <ikedamsh@oss.nttdata.com>
Reviewed-By: Masahiro Ikeda <ikedamsh@oss.nttdata.com>
Discussion: https://postgr.es/m/f8efb9c0f8d1a71b44fd7f8e42e49c25@oss.nttdata.com
We now create contype='n' pg_constraint rows for not-null constraints on
user tables. Only one such constraint is allowed for a column.
We propagate these constraints to other tables during operations such as
adding inheritance relationships, creating and attaching partitions and
creating tables LIKE other tables. These related constraints mostly
follow the well-known rules of conislocal and coninhcount that we have
for CHECK constraints, with some adaptations: for example, as opposed to
CHECK constraints, we don't match not-null ones by name when descending
a hierarchy to alter or remove it, instead matching by the name of the
column that they apply to. This means we don't require the constraint
names to be identical across a hierarchy.
The inheritance status of these constraints can be controlled: now we
can be sure that if a parent table has one, then all children will have
it as well. They can optionally be marked NO INHERIT, and then children
are free not to have one. (There's currently no support for altering a
NO INHERIT constraint into inheriting down the hierarchy, but that's a
desirable future feature.)
This also opens the door for having these constraints be marked NOT
VALID, as well as allowing UNIQUE+NOT NULL to be used for functional
dependency determination, as envisioned by commit e49ae8d3bc. It's
likely possible to allow DEFERRABLE constraints as followup work, as
well.
psql shows these constraints in \d+, though we may want to reconsider if
this turns out to be too noisy. Earlier versions of this patch hid
constraints that were on the same columns of the primary key, but I'm
not sure that that's very useful. If clutter is a problem, we might be
better off inventing a new \d++ command and not showing the constraints
in \d+.
For now, we omit these constraints on system catalog columns, because
they're unlikely to achieve anything.
The main difference to the previous attempt at this (b0e96f3119) is
that we now require that such a constraint always exists when a primary
key is in the column; we didn't require this previously which had a
number of unpalatable consequences. With this requirement, the code is
easier to reason about. For example:
- We no longer have "throwaway constraints" during pg_dump. We needed
those for the case where a table had a PK without a not-null
underneath, to prevent a slow scan of the data during restore of the
PK creation, which was particularly problematic for pg_upgrade.
- We no longer have to cope with attnotnull being set spuriously in
case a primary key is dropped indirectly (e.g., via DROP COLUMN).
Some bits of code in this patch were authored by Jian He.
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Author: Bernd Helmle <mailings@oopsware.de>
Reviewed-by: 何建 (jian he) <jian.universality@gmail.com>
Reviewed-by: 王刚 (Tender Wang) <tndrwang@gmail.com>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Discussion: https://postgr.es/m/202408310358.sdhumtyuy2ht@alvherre.pgsql
If the collation of any join key column doesn’t match the collation of
the corresponding partition key, partitionwise joins can yield incorrect
results. For example, rows that would match under the join key collation
might be located in different partitions due to the partitioning
collation. In such cases, a partitionwise join would yield different
results from a non-partitionwise join, so disallow it in such cases.
Reported-by: Tender Wang <tndrwang@gmail.com>
Author: Jian He <jian.universality@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Discussion: https://postgr.es/m/CAHewXNno_HKiQ6PqyLYfuqDtwp7KKHZiH1J7Pqyz0nr+PS2Dwg@mail.gmail.com
Backpatch-through: 12
If the collation of any grouping column doesn’t match the collation of
the corresponding partition key, partitionwise grouping can yield
incorrect results. For example, rows that would be grouped under the
grouping collation may end up in different partitions under the
partitioning collation. In such cases, full partitionwise grouping
would produce results that differ from those without partitionwise
grouping, so disallowed that.
Partial partitionwise aggregation is still allowed, as the Finalize
step reconciles partition-level aggregates with grouping requirements
across all partitions, ensuring that the final output remains
consistent.
This commit also fixes group_by_has_partkey() by ensuring the
RelabelType node is stripped from grouping expressions when matching
them to partition key expressions to avoid false mismatches.
Bug: #18568
Reported-by: Webbo Han <1105066510@qq.com>
Author: Webbo Han <1105066510@qq.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Aleksander Alekseev <aleksander@timescale.com>
Reviewed-by: Jian He <jian.universality@gmail.com>
Discussion: https://postgr.es/m/18568-2a9afb6b9f7e6ed3@postgresql.org
Discussion: https://postgr.es/m/tencent_9D9103CDA420C07768349CC1DFF88465F90A@qq.com
Discussion: https://postgr.es/m/CAHewXNno_HKiQ6PqyLYfuqDtwp7KKHZiH1J7Pqyz0nr+PS2Dwg@mail.gmail.com
Backpatch-through: 12
When we generate multiple clones of the same qual condition to cope
with outer join identity 3, we need to ensure that all the clones get
the same serial number. To achieve this, we reset the
root->last_rinfo_serial counter each time we produce RestrictInfo(s)
from the qual list (see deconstruct_distribute_oj_quals). This
approach works only if we ensure that we are not changing the qual
list in any way that'd affect the number of RestrictInfos built from
it.
However, with b262ad440, an IS NULL qual on a NOT NULL column might
result in an additional constant-FALSE RestrictInfo. And different
versions of the same qual clause can lead to different conclusions
about whether it can be reduced to constant-FALSE. This would affect
the number of RestrictInfos built from the qual list for different
versions, causing inconsistent RestrictInfo serial numbers across
multiple clones of the same qual. This inconsistency can confuse
users of these serial numbers, such as rebuild_joinclause_attr_needed,
and lead to planner errors such as "ERROR: variable not found in
subplan target lists".
To fix, reset the root->last_rinfo_serial counter after generating the
additional constant-FALSE RestrictInfo.
Back-patch to v17 where the issue crept in. In v17, I failed to make
a test case that would expose this bug, so no test case for v17.
Author: Richard Guo
Discussion: https://postgr.es/m/CAMbWs4-B6kafn+LmPuh-TYFwFyEm-vVj3Qqv7Yo-69CEv14rRg@mail.gmail.com
This patch builds on the work done in commit 745217a051 by enabling the
replication of generated columns alongside regular column changes through
a new publication parameter: publish_generated_columns.
Example usage:
CREATE PUBLICATION pub1 FOR TABLE tab_gencol WITH (publish_generated_columns = true);
The column list takes precedence. If the generated columns are specified
in the column list, they will be replicated even if
'publish_generated_columns' is set to false. Conversely, if generated
columns are not included in the column list (assuming the user specifies a
column list), they will not be replicated even if
'publish_generated_columns' is true.
Author: Vignesh C, Shubham Khanna
Reviewed-by: Peter Smith, Amit Kapila, Hayato Kuroda, Shlok Kyal, Ajin Cherian, Hou Zhijie, Masahiko Sawada
Discussion: https://postgr.es/m/B80D17B2-2C8E-4C7D-87F2-E5B4BE3C069E@gmail.com
The low variable has not been used since it was added in d168b66682
and can be safely removed. The variable is present in the Sedgewick
paper "Analysis of Shellsort and Related Algorithms" as a parameter
to the shellsort function, but our implementation does not use it.
Remove to improve readability of the code.
Author: Koki Nakamura <btnakamurakoukil@oss.nttdata.com>
Discussion: https://postgr.es/m/8aeb7b3eda53ca4c65fbacf8f43628fb@oss.nttdata.com
This is difficult to maintain accurately, and it was probably already
somewhat incorrect, especially in the sql_drop and table_rewrite
categories.
The prior section already documented which DDL commands are *not*
supported (which was also slightly outdated), so let's expand that a
bit and just rely on that instead of listing out each command in full
detail.
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Jian He <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CACJufxE_UAuxcM08BW5oVsg34v0cFWoEt8yBa5xSAoKLmL6LTQ%40mail.gmail.com
Supply a new memory manager for RuntimeDyld, to avoid crashes in
generated code caused by memory placement that can overflow a 32 bit
data type. This is a drop-in replacement for the
llvm::SectionMemoryManager class in the LLVM library, with Michael
Smith's proposed fix from
https://www.github.com/llvm/llvm-project/pull/71968.
We hereby slurp it into our own source tree, after moving into a new
namespace llvm::backport and making some minor adjustments so that it
can be compiled with older LLVM versions as far back as 12. It's harder
to make it work on even older LLVM versions, but it doesn't seem likely
that people are really using them so that is not investigated for now.
The problem could also be addressed by switching to JITLink instead of
RuntimeDyld, and that is the LLVM project's recommended solution as
the latter is about to be deprecated. We'll have to do that soon enough
anyway, and then when the LLVM version support window advances far
enough in a few years we'll be able to delete this code. Unfortunately
that wouldn't be enough for PostgreSQL today: in most relevant versions
of LLVM, JITLink is missing or incomplete.
Several other projects have already back-ported this fix into their fork
of LLVM, which is a vote of confidence despite the lack of commit into
LLVM as of today. We don't have our own copy of LLVM so we can't do
exactly what they've done; instead we have a copy of the whole patched
class so we can pass an instance of it to RuntimeDyld.
The LLVM project hasn't chosen to commit the fix yet, and even if it
did, it wouldn't be back-ported into the releases of LLVM that most of
our users care about, so there is not much point in waiting any longer
for that. If they make further changes and commit it to LLVM 19 or 20,
we'll still need this for older versions, but we may want to
resynchronize our copy and update some comments.
The changes that we've had to make to our copy can be seen by diffing
our SectionMemoryManager.{h,cpp} files against the ones in the tree of
the pull request. Per the LLVM project's license requirements, a copy
is in SectionMemoryManager.LICENSE.
This should fix the spate of crash reports we've been receiving lately
from users on large memory ARM systems.
Back-patch to all supported releases.
Co-authored-by: Thomas Munro <thomas.munro@gmail.com>
Co-authored-by: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com>
Reviewed-by: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se> (license aspects)
Reported-by: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com>
Discussion: https://postgr.es/m/CAO6_Xqr63qj%3DSx7HY6ZiiQ6R_JbX%2B-p6sTPwDYwTWZjUmjsYBg%40mail.gmail.com
adf97c156 gave ExprStates the ability to hash expressions and return a
single hash value. That commit supports seeding the hash value with an
initial value to have that blended into the final hash value.
Here we fix a hypothetical bug where if there are zero expressions to
hash, the initial value is stored in the wrong location. The existing
code stored the initial value in an intermediate location expecting that
when the expressions were hashed that those steps would store the final
hash value in the ExprState.resvalue field. However, that wouldn't happen
when there are zero expressions to hash. The correct thing to do instead
is to have a special case for zero expressions and when we hit that case,
store the initial value directly in the ExprState.resvalue. The reason
that this is a hypothetical bug is that no code currently calls
ExecBuildHash32Expr passing a non-zero initial value.
Discussion: https://postgr.es/m/CAApHDvpMAL_zxbMRr1LOex3O7Y7R7ZN2i8iUFLQhqQiJMAg3qw@mail.gmail.com
PgStat_HashKey is currently initialized in a way that could result in
random data if the structure has any padding bytes. The structure
has no padding bytes currently, fortunately, but it could become a
problem should the structure change at some point in the future.
The code is changed to use some memset(0) so as any padding would be
handled properly, as it would be surprising to see random failures in
the pgstats entry lookups. PgStat_HashKey is a structure internal to
pgstats, and an ABI change could be possible in the scope of a bug fix,
so backpatch down to 15 where this has been introduced.
Author: Bertrand Drouvot
Reviewed-by: Jelte Fennema-Nio, Michael Paquier
Discussion: https://postgr.es/m/Zyb7RW1y9dVfO0UH@ip-10-97-1-34.eu-west-3.compute.internal
Backpatch-through: 15
_bt_first doesn't necessarily hold onto a buffer pin on success exit.
Fix header comments that claimed that we'll always hold onto a pin.
Oversight in commit 2ed5b87f96.
Remove a local variable that was used to avoid overwriting strat_total
with the = operator strategy when a >= operator strategy key was already
included in the initial positioning/insertion scan keys by _bt_first
(for backwards scans it would have to be a <= key that was included).
_bt_first's strat_total local variable now simply tracks the operator
strategy of the final scan key that was included in the scan's insertion
scan key (barring the case where the !used_all_subkeys row compare path
adjusts strat_total in its own way).
_bt_first already treated >= keys (or <= keys) as = keys for initial
positioning purposes. There is no good reason to remember that that was
what happened; no later _bt_first step cares about the distinction.
Note, in particular, that the insertion scan key's 'nextkey' and
'backward' fields will be initialized the same way regardless.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CAH2-Wz=PKR6rB7qbx+Vnd7eqeB5VTcrW=iJvAsTsKbdG+kW_UA@mail.gmail.com
Split ProcSleep into two functions: JoinWaitQueue and ProcSleep.
JoinWaitQueue is called while holding the partition lock, and inserts
the current process to the wait queue, while ProcSleep() does the
actual sleeping. ProcSleep() is now called without holding the
partition lock, and it no longer re-acquires the partition lock before
returning. That makes the wakeup a little cheaper. Once upon a time,
re-acquiring the partition lock was needed to prevent a signal handler
from longjmping out at a bad time, but these days our signal handlers
just set flags, and longjmping can only happen at points where we
explicitly run CHECK_FOR_INTERRUPTS().
If JoinWaitQueue detects an "early deadlock" before even joining the
wait queue, it returns without changing the shared lock entry, leaving
the cleanup of the shared lock entry to the caller. This makes the
handling of an early deadlock the same as the dontWait=true case.
One small user-visible side-effect of this refactoring is that we now
only set the 'ps' title to say "waiting" when we actually enter the
sleep, not when the lock is skipped because dontWait=true, or when a
deadlock is detected early before entering the sleep.
This eliminates the 'lockAwaited' global variable in proc.c, which was
largely redundant with 'awaitedLock' in lock.c
Note: Updating the local lock table is now the caller's responsibility.
JoinWaitQueue and ProcSleep are now only responsible for modifying the
shared state. Seems a little nicer that way.
Based on Thomas Munro's earlier patch and observation that ProcSleep
doesn't really need to re-acquire the partition lock.
Reviewed-by: Maxim Orlov
Discussion: https://www.postgresql.org/message-id/7c2090cd-a72a-4e34-afaa-6dd2ef31440e@iki.fi
Previously, ProcSleep()'s caller was responsible for setting
MyProc->heldLocks, and we had comments to remind about that. But it
seems simpler to make ProcSleep() itself responsible for it.
ProcSleep() already set the other info about the lock its waiting for
(waitLock, waitProcLock and waitLockMode), so it is natural for it to
set heldLocks too.
Reviewed-by: Maxim Orlov
Discussion: https://www.postgresql.org/message-id/7c2090cd-a72a-4e34-afaa-6dd2ef31440e@iki.fi
_bt_endpoint is a helper function for _bt_first that's called whenever
no useful insertion scan key can be used, and we need to lock and read
either the leftmost or rightmost leaf page in the index. Simplify and
document its preconditions, relieving its _bt_first caller from having
to end the parallel scan when it returns false.
Also stop unnecessarily invalidating the current scan position in nearby
code in both _bt_first and _bt_endpoint. This seems to have been
copy-pasted from _bt_readnextpage, where invalidating the scan's current
position really is necessary.
Follow-up to the refactoring work in commit 1bd4bc85.
A CacheInvalidateHeapTuple* callee might call
CatalogCacheInitializeCache(), which needs a relcache entry. Acquiring
a valid relcache entry might scan pg_class. Hence, to prevent
undetected LWLock self-deadlock, CacheInvalidateHeapTuple* callers must
not hold BUFFER_LOCK_EXCLUSIVE on buffers of pg_class. Move the
CacheInvalidateHeapTupleInplace() before the BUFFER_LOCK_EXCLUSIVE. No
back-patch, since I've reverted commit
243e9b40f1 from non-master branches.
Reported by Alexander Lakhin. Reviewed by Alexander Lakhin.
Discussion: https://postgr.es/m/10ec0bc3-5933-1189-6bb8-5dec4114558e@gmail.com
Commit a07e03fd8f enlarged the work done
here under the pg_class heap buffer lock. Two preexisting actions are
best done before holding that lock. Both RelationGetNumberOfBlocks()
and visibilitymap_count() do I/O, and the latter might exclusive-lock a
visibility map buffer. Moving these reduces contention and risk of
undetected LWLock deadlock. Back-patch to v12, like that commit.
Discussion: https://postgr.es/m/20241031200139.b4@rfd.leadboat.com
Instead of talking about setting latches, which is a pretty low-level
mechanism, emphasize that they wake up other processes.
This is in preparation for replacing Latches with a new abstraction.
That's still work in progress, but this seems a little tidier anyway,
so let's get this refactoring out of the way already.
Discussion: https://www.postgresql.org/message-id/391abe21-413e-4d91-a650-b663af49500c%40iki.fi
After a closer lookup, this makes the all-zero check of the page more
expensive, so let's remove the new function call in bufpage.c. The
maths of the check were also incorrect, checking that the page was full
of zeros only for the first 1kB.
This brings back the code to the state it was at 49d6c7d8da.
Per discussion with David Rowley and Bertrand Drouvot.
Discussion: https://postgr.es/m/CAApHDvrXzPAr3FxoBuB7b3D-okNoNA2jxLun1rW8Yw5wkbqusw@mail.gmail.com
This new function tests if a memory region starting at a given location
for a defined length is made only of zeroes. This unifies in a single
path the all-zero checks that were happening in a couple of places of
the backend code:
- For pgstats entries of relation, checkpointer and bgwriter, where
some "all_zeroes" variables were previously used with memcpy().
- For all-zero buffer pages in PageIsVerifiedExtended().
This new function uses the same forward scan as the check for all-zero
buffer pages, applying it to the three pgstats paths mentioned above.
Author: Bertrand Drouvot
Reviewed-by: Peter Eisentraut, Heikki Linnakangas, Peter Smith
Discussion: https://postgr.es/m/ZupUDDyf1hHI4ibn@ip-10-97-1-34.eu-west-3.compute.internal
This function takes in input an array, and reverses the position of all
its elements. This operation only affects the first dimension of the
array, like array_shuffle().
The implementation structure is inspired by array_shuffle(), with a
subroutine called array_reverse_n() that may come in handy in the
future, should more functions able to reverse portions of arrays be
introduced.
Bump catalog version.
Author: Aleksander Alekseev
Reviewed-by: Ashutosh Bapat, Tom Lane, Vladlen Popolitov
Discussion: https://postgr.es/m/CAJ7c6TMpeO_ke+QGOaAx9xdJuxa7r=49-anMh3G5476e3CX1CA@mail.gmail.com
This patch responds to a comment that I (tgl) made in the
discussion leading up to 774171c4f, that really all errors
occurring during raw parsing should provide error cursors.
Syntax errors reported by Bison will have one, and most of
the handwritten ereport's in gram.y already provide one,
but there were a few stragglers.
(It is not claimed that this handles every failure reachable
during raw parsing --- out-of-memory is an obvious exception.
But this makes a good start on cases that are likely to occur.)
While we're at it, clean up the reported positions for errors
associated with LIMIT/OFFSET clauses. Previously we were
relying on applying exprLocation() to the contained expressions,
but that leads to slightly odd cursor placement, e.g.
regression=# (select * from foo limit 10) limit 10;
ERROR: multiple LIMIT clauses not allowed
LINE 1: (select * from foo limit 10) limit 10;
^
We can afford to keep a little more state in the transient
SelectLimit structs in order to make that better.
Jian He and Tom Lane (extracted from a larger patch by Jian,
with some additional work by me)
Discussion: https://postgr.es/m/CACJufxEmONE3P2En=jopZy1m=cCCUs65M4+1o52MW5og9oaUPA@mail.gmail.com
This allows an error cursor to be supplied for a bunch of
bad-function-definition errors that previously lacked one,
or that cheated a bit by pointing at the contained type name
when the error isn't really about that.
Bump catversion from an abundance of caution --- I don't think
this node type can actually appear in stored views/rules, but
better safe than sorry.
Jian He and Tom Lane (extracted from a larger patch by Jian,
with some additional work by me)
Discussion: https://postgr.es/m/CACJufxEmONE3P2En=jopZy1m=cCCUs65M4+1o52MW5og9oaUPA@mail.gmail.com
Buildfarm member 'prion', which is configured with
-DRELCACHE_FORCE_RELEASE -DCATCACHE_FORCE_RELEASE, failed with errors
like this:
ERROR: could not read blocks 0..0 in file "global/2672": read only 0 of 8192 bytes
while running a parallel test group that includes VACUUM FULL on some
catalog tables among other things. I was not able to reproduce that
just by running the tests with -DRELCACHE_FORCE_RELEASE
-DCATCACHE_FORCE_RELEASE, even though 'prion' hit it on first run
after commit 2b9b8ebbf8, so there might be something else that makes
it more susceptible to the race. However, I was able to reproduce it
by adding another test to the same test group that runs "vacuum full
pg_database" repeatedly.
The problem is that RelationReloadIndexInfo() no longer calls
RelationInitPhysicalAddr() on a nailed, shared index, when an
invalidation happens early during backend startup, before the critical
relcaches have been built. Before commit 2b9b8ebbf8, that was done by
RelationReloadNailed(), but it went missing from that path. Add it
back as an explicit step.
Broken by commit 2b9b8ebbf8, which refactored these functions.
Discussion: https://www.postgresql.org/message-id/db876575-8f5b-4193-a538-df7e1f92d47a%40iki.fi
The old RelationClearRelation function did different things depending
on the arguments and circumstances. It could:
a) remove the relation completely from relcache (rebuild == false),
b) mark the entry as invalid (rebuild == true, but not in xact), or
c) rebuild the entry (rebuild == true).
Different callers used it for different purposes, and often assumed a
particular behavior, which was confusing. Split it into three
different functions, one for each of the above actions (one of them,
RelationInvalidateRelation, was already added in commit e6cd857726).
Move the responsibility of choosing the action and calling the right
function to the callers.
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/9c9e8908-7b3e-4ce7-85a8-00c0e165a3d6%40iki.fi
RelationClearRelation(rebuild == true) calls RelationReloadIndexInfo()
for indexes. We can rely on that in RelationIdGetRelation(), instead
of calling RelationReloadIndexInfo() directly. That simplifies the
code a little.
In the passing, add a comment in RelationBuildLocalRelation()
explaining why it doesn't call RelationInitIndexAccessInfo(). It's
because at index creation, it's called before the pg_index row has
been created. That's also the reason that RelationClearRelation()
still needs a special case to go through the full-blown rebuild if the
index support information in the relcache entry hasn't been populated
yet.
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/9c9e8908-7b3e-4ce7-85a8-00c0e165a3d6%40iki.fi
Follow-up to bugfix commit 763d65ae. Technically this new assertion is
redundant with the assertion recently added to _bt_readpage by that same
commit, but it seems like a good idea to have both.
The new assertion makes it clear that we expect to call _bt_readnextpage
when there's another primitive index scan scheduled, though only when
needed as the final step of ending the current primitive scan.
Strictly speaking, we only need to make sure to leave the scan's array
keys in their final positions (final for the current scan direction) to
handle SAOP array exhaustion because btgettuple might only return a
subset of the items for the final page (final for the current scan
direction), before the scan changes direction. While it's typical for
so->currPos to be invalidated shortly after the scan's arrays are first
exhausted, and while so->currPos invalidation does obviate the need to
leave the scan's arrays in any particular state, we can't rely on any of
that actually happening when handling array exhaustion. Adjust comments
to make all of that a lot clearer.
Oversight in commit 5bf748b8, which enhanced nbtree ScalarArrayOp
execution.
A bug in nbtree's handling of primitive index scan scheduling could lead
to wrong answers when a scrollable cursor was used with an index scan
that had a SAOP index qual. Wrong answers were only possible when the
scan direction changed after a primitive scan was scheduled, but before
_bt_next was asked to fetch the next tuple in line (i.e. for things to
break, _bt_next had to be denied the opportunity to step off the page in
the same direction as the one used when the primscan was scheduled).
Furthermore, the issue only occurred when the page in question happened
to be the first page to be visited by the entire top-level scan; the
issue hinged upon the cursor backing up to the absolute beginning of the
key space that it returns tuples from (fetching in the opposite scan
direction across a "primitive scan boundary" always worked correctly).
To fix, make _bt_next unset the "needs primitive index scan" flag when
it detects that the current scan direction is not the one that was used
by _bt_readpage back when the primitive scan in question was scheduled.
This fixes the cases that are known to be faulty, and also seems like a
good idea on general robustness grounds.
Affected scrollable cursor cases now avoid a spurious primitive index
scan when they fetch backwards to the absolute start of the key space to
be visited by their cursor. Fetching backwards now only returns those
tuples at the start of the scan, as expected. It'll also be okay to
once again fetch forwards from the start at that point, since the scan
will be left in a state that's exactly consistent with the state it was
in before any tuples were ever fetched, as expected.
Oversight in commit 5bf748b8, which enhanced nbtree ScalarArrayOp
execution.
Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-Wznv49bFsE2jkt4GuZ0tU2C91dEST=50egzjY2FeOcHL4Q@mail.gmail.com
Backpatch: 17-, where commit 5bf748b8 first appears.
* In DetachPartitionFinalize() we were applying a tuple conversion map
to tuples that didn't need one, which can lead to erratic behavior if
a partitioned table has a partition with a different column order, as
reported by Alexander Lakhin. This was introduced by 53af9491a0.
Don't do that. Also, modify a recently added test case to exercise
this.
* The same function as well as CloneFkReferenced() were acquiring
AccessShareLock on a partition, only to have CreateTrigger() later
acquire ShareRowExclusiveLock on it. This can lead to deadlock by
lock escalation, unnecessarily. Avoid that by acquiring the stronger
lock to begin with. This probably dates back to branch 12, but I have
never seen a report of this being a problem in the field.
* Innocuous but wasteful: also introduced by 53af9491a0, we were
reading a pg_constraint tuple from syscache that we don't need, as
reported by Tender Wang. Don't.
Backpatch to 15.
Discussion: https://postgr.es/m/461e9c26-2076-8224-e119-84998b6a784e@gmail.com
This commit allows logical replication to publish and replicate generated
columns when explicitly listed in the column list. We also ensured that
the generated columns were copied during the initial tablesync when they
were published.
We will allow to replicate generated columns even when they are not
specified in the column list (via a new publication option) in a separate
commit.
The motivation of this work is to allow replication for cases where the
client doesn't have generated columns. For example, the case where one is
trying to replicate data from Postgres to the non-Postgres database.
Author: Shubham Khanna, Vignesh C, Hou Zhijie
Reviewed-by: Peter Smith, Hayato Kuroda, Shlok Kyal, Amit Kapila
Discussion: https://postgr.es/m/B80D17B2-2C8E-4C7D-87F2-E5B4BE3C069E@gmail.com
Commit a07e03fd8f changed inplace updates
to wait for heap_update() commands like GRANT TABLE and GRANT DATABASE.
By keeping the pin during that wait, a sequence of autovacuum workers
and an uncommitted GRANT starved one foreground LockBufferForCleanup()
for six minutes, on buildfarm member sarus. Prevent, at the cost of a
bit of complexity. Back-patch to v12, like the earlier commit. That
commit and heap_inplace_lock() have not yet appeared in any release.
Discussion: https://postgr.es/m/20241026184936.ae.nmisch@google.com
A pg_depend entry between a partitioned table and its table access
method was missing when using CREATE TABLE .. USING with an unpinned
access method. DROP ACCESS METHOD could be used, while it should be
blocked if CASCADE is not specified, even if there was a partitioned
table that depends on the table access method. pg_class.relam would
then hold an orphaned OID value still pointing to the AM dropped.
The problem is fixed by adding a dependency between the partitioned
table and its table access method if set when the relation is created.
A test checking the contents of pg_depend in this case is added.
Issue introduced in 374c7a2290, that has added support for CREATE
TABLE .. USING for partitioned tables.
Reviewed-by: Alexander Lakhin
Discussion: https://postgr.es/m/18674-1ef01eceec278fab@postgresql.org
Backpatch-through: 17
I assumed that all index_drop() callers set an active snapshot
beforehand, but that is evidently not true. One counterexample is
autovacuum, which doesn't set an active snapshot when cleaning up
orphan temp indexes. To fix, unconditionally push an active
snapshot before updating pg_index in index_drop().
Oversight in commit b52adbad46.
Reported-by: Masahiko Sawada
Reviewed-by: Stepan Neretin, Masahiko Sawada
Discussion: https://postgr.es/m/CAD21AoBgF9etQrXbN9or_YHsmBRJHHNUEkhHp9rGK9CyQv5aTQ%40mail.gmail.com
Revert commit 924e03917 in favor of adding code to convert \r\n to \n
explicitly, on Windows only. The idea of letting text mode do the
work fails for a couple of reasons:
* Per Microsoft documentation, text mode also causes control-Z to be
interpreted as end-of-file. While it may be unlikely that extension
scripts contain control-Z, we've historically allowed it, and breaking
the case doesn't seem wise.
* Apparently, on some Windows configurations, "r" mode is interpreted
as binary not text mode. We could force it with "rt" but that would
be inconsistent with our code elsewhere, and it would still require
Windows-specific coding.
Thanks to Alexander Lakhin for investigation.
Discussion: https://postgr.es/m/79284195-4993-7b00-f6df-8db28ca60fa3@gmail.com
Tweak some code comments for clarity, and relocate some local variable
declarations to the scope where they're actually used.
Follow-up to recent commit 1bd4bc85.
Previously the default value of streaming option for a subscription was
'off'. The parallel option indicates that the changes in large
transactions (greater than logical_decoding_work_mem) are to be applied
directly via one of the parallel apply workers, if available.
The parallel mode was introduced in 16, but we refrain from enabling it by
default to avoid seeing any unpleasant behavior in the existing
applications. However we haven't found any such report yet, so this is a
good time to enable it by default.
Reported-by: Vignesh C
Author: Hayato Kuroda, Masahiko Sawada, Peter Smith, Amit Kapila
Discussion: https://postgr.es/m/CALDaNm1=MedhW23NuoePJTmonwsMSp80ddsw+sEJs0GUMC_kqQ@mail.gmail.com
Some utility statements contain queries that can be planned and
executed: CREATE TABLE AS and DECLARE CURSOR. This commit adds query ID
computation for the inner queries executed by these two utility
commands, with and without EXPLAIN. This change leads to four new
callers of JumbleQuery() and post_parse_analyze_hook() so as extensions
can decide what to do with this new data.
Previously, extensions relying on the query ID, like pg_stat_statements,
were not able to track these nested queries as the query_id was 0.
For pg_stat_statements, this commit leads to additions under !toplevel
when pg_stat_statements.track is set to "all", as shown in its
regression tests. The output of EXPLAIN for these two utilities gains a
"Query Identifier" if compute_query_id is enabled.
Author: Anthonin Bonnefoy
Reviewed-by: Michael Paquier, Jian He
Discussion: https://postgr.es/m/CAO6_XqqM6S9bQ2qd=75W+yKATwoazxSNhv5sjW06fjGAtHbTUA@mail.gmail.com
This change affects only Windows, where it should cause DOS-style
newlines (\r\n) to be converted to plain \n during script loading.
This eliminates one potential discrepancy in the behavior of
extension script files between Windows and non-Windows. While
there's a small chance that this might cause undesirable behavior
changes for some extensions, it can also be argued that this may
remove behavioral surprises for others. An example is that in
the buildfarm, we are getting different results for the tests
added by commit 774171c4f depending on whether our git tree has
been checked out with Unix or DOS newlines.
The choice to use binary mode goes all the way back to our invention
of extensions in commit d9572c4e3. However, I suspect it was not
thought through carefully but was just a side-effect of the ready
availability of an almost-suitable function read_binary_file().
On balance, changing to text mode seems like a better answer than
other ways in which we might fix the inconsistent test results.
Discussion: https://postgr.es/m/2480333.1729784872@sss.pgh.pa.us
Move all responsibility for indicating a block is exhuasted into
table_scan_bitmap_next_tuple() and advance the main iterator in
heap-specific code. This flow control makes more sense and is a step
toward using the read stream API for bitmap heap scans.
Previously, table_scan_bitmap_next_block() returned false to indicate
table_scan_bitmap_next_tuple() should not be called for the tuples on
the page. This happened both when 1) there were no visible tuples on the
page and 2) when the block returned by the iterator was past the end of
the table. BitmapHeapNext() (generic bitmap table scan code) handled the
case when the bitmap was exhausted.
It makes more sense for table_scan_bitmap_next_tuple() to return false
when there are no visible tuples on the page and
table_scan_bitmap_next_block() to return false when the bitmap is
exhausted or there are no more blocks in the table.
As part of this new design, TBMIterateResults are no longer used as a
flow control mechanism in BitmapHeapNext(), so we removed
table_scan_bitmap_next_tuple's TBMIterateResult parameter.
Note that the prefetch iterator is still saved in the
BitmapHeapScanState node and advanced in generic bitmap table scan code.
This is because 1) it was not necessary to change the prefetch iterator
location to change the flow control in BitmapHeapNext() 2) modifying
prefetch iterator management requires several more steps better split
over multiple commits and 3) the prefetch iterator will be removed once
the read stream API is used.
Author: Melanie Plageman
Reviewed-by: Tomas Vondra, Andres Freund, Heikki Linnakangas, Mark Dilger
Discussion: https://postgr.es/m/063e4eb4-32d9-439e-a0b1-75565a9835a8%40iki.fi
Increment the lossy and exact page counters for EXPLAIN of bitmap heap
scans in heapam_scan_bitmap_next_block(). Note that other table AMs will
need to do this as well
Pushing the counters into heapam_scan_bitmap_next_block() is required to
be able to use the read stream API for bitmap heap scans. The bitmap
iterator must be advanced from inside the read stream callback, so
TBMIterateResults cannot be used as a flow control mechanism in
BitmapHeapNext().
Author: Melanie Plageman
Reviewed-by: Tomas Vondra, Heikki Linnakangas
Discussion: https://postgr.es/m/063e4eb4-32d9-439e-a0b1-75565a9835a8%40iki.fi
A buffer lock won't stop a reader having already checked tuple
visibility. If a vac_update_datfrozenid() and then a crash happened
during inplace update of a relfrozenxid value, datfrozenxid could
overtake relfrozenxid. That could lead to "could not access status of
transaction" errors. Back-patch to v12 (all supported versions). In
v14 and earlier, this also back-patches the assertion removal from
commit 7fcf2faf9c.
Discussion: https://postgr.es/m/20240620012908.92.nmisch@google.com
The inplace update survives ROLLBACK. The inval didn't, so another
backend's DDL could then update the row without incorporating the
inplace update. In the test this fixes, a mix of CREATE INDEX and ALTER
TABLE resulted in a table with an index, yet relhasindex=f. That is a
source of index corruption. Back-patch to v12 (all supported versions).
The back branch versions don't change WAL, because those branches just
added end-of-recovery SIResetAll(). All branches change the ABI of
extern function PrepareToInvalidateCacheTuple(). No PGXN extension
calls that, and there's no apparent use case in extensions.
Reviewed by Nitin Motiani and (in earlier versions) Andres Freund.
Discussion: https://postgr.es/m/20240523000548.58.nmisch@google.com
The existing get_publications_str() is renamed to GetPublicationsStr()
and is moved to pg_subscription.c, so as it is possible to reuse it at
two locations of the tablesync code where the same logic was duplicated.
fetch_remote_table_info() was doing two List->StringInfo conversions
when dealing with a server of version 15 or newer. The conversion
happens only once now.
This refactoring leads to less code overall.
Author: Peter Smith
Reviewed-by: Michael Paquier, Masahiko Sawada
Discussion: https://postgr.es/m/CAHut+PtJMk4bKXqtpvqVy9ckknCgK9P6=FeG8zHF=6+Em_Snpw@mail.gmail.com
For an EXISTS subquery, the only thing that matters is whether it
returns zero or more than zero rows. Therefore, we remove certain SQL
features that won't affect that, among them the GROUP BY clauses.
After we drop the groupClause, we'd better remove the RTE_GROUP RTE
and clear the hasGroupRTE flag, as they depend on the groupClause.
Failing to do so could result in a bogus RTE_GROUP entry in the parent
query, leading to an assertion failure on the hasGroupRTE flag.
Reported-by: David Rowley
Author: Richard Guo
Discussion: https://postgr.es/m/CAApHDvp2_yht8uPLyWO-kVGWZhYvx5zjGfSrg4fBQ9fsC13V0g@mail.gmail.com
Similar to the pg_set_*_stats() functions, except with a variadic
signature that's designed to be more future-proof. Additionally, most
problems are reported as WARNINGs rather than ERRORs, allowing most
stats to be restored even if some cannot.
These functions are intended to be called from pg_dump to avoid the
need to run ANALYZE after an upgrade.
Author: Corey Huinker
Discussion: https://postgr.es/m/CADkLM=eErgzn7ECDpwFcptJKOk9SxZEk5Pot4d94eVTZsvj3gw@mail.gmail.com
Reunite RestorePendingSyncs() with RestoreRelationMap(). If
RelationInitPhysicalAddr() ran after RestoreRelationMap() but before
RestorePendingSyncs(), the relcache entry could cause RelationNeedsWAL()
to return true erroneously. Trouble required commands of the current
transaction to include REINDEX or CLUSTER of a system catalog. The
parallel leader correctly derived RelationNeedsWAL()==false from the new
relfilenumber, but the worker saw RelationNeedsWAL()==true. Worker
MarkBufferDirtyHint() then wrote unwanted WAL. Recovery of that
unwanted WAL could lose tuples like the system could before commit
c6b92041d3 introduced this tracking.
RestorePendingSyncs() and RestoreRelationMap() were adjacent till commit
126ec0bc76, so no back-patch for now.
Reviewed by Tom Lane.
Discussion: https://postgr.es/m/20241019232815.c6.nmisch@google.com
Previously, GetLockStatusData() checked all slots for every backend
to gather fast-path lock data, which could be inefficient. This commit
refactors it by skipping backends with PID=0 (since they don't hold
fast-path locks) and skipping groups with no registered fast-path locks,
improving efficiency.
This refactoring is particularly beneficial, for example when
max_connections and max_locks_per_transaction are set high,
as it reduces unnecessary checks across numerous slots.
Author: Fujii Masao
Reviewed-by: Bertrand Drouvot
Discussion: https://postgr.es/m/a0a00c44-31e9-4c67-9846-fb9636213ac9@oss.nttdata.com
The ssl_ciphers GUC can only set cipher suites for TLSv1.2, and lower,
connections. For TLSv1.3 connections a different OpenSSL API must be
used. This adds a new GUC, ssl_tls13_ciphers, which can be used to
configure a colon separated list of cipher suites to support when
performing a TLSv1.3 handshake.
Original patch by Erica Zhang with additional hacking by me.
Author: Erica Zhang <ericazhangy2021@qq.com>
Author: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Jacob Champion <jacob.champion@enterprisedb.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Jelte Fennema-Nio <postgres@jeltef.nl>
Discussion: https://postgr.es/m/tencent_063F89FA72CCF2E48A0DF5338841988E9809@qq.com
The ssl_ecdh_curve GUC only accepts a single value, but the TLS
handshake can list multiple curves in the groups extension (the
extension has been renamed to contain more than elliptic curves).
This changes the GUC to accept a colon-separated list of curves.
This commit also renames the GUC to ssl_groups to match the new
nomenclature for the TLS extension.
Original patch by Erica Zhang with additional hacking by me.
Author: Erica Zhang <ericazhangy2021@qq.com>
Author: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Jacob Champion <jacob.champion@enterprisedb.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Jelte Fennema-Nio <postgres@jeltef.nl>
Discussion: https://postgr.es/m/tencent_063F89FA72CCF2E48A0DF5338841988E9809@qq.com
This argument allow skipping throwing an error. Instead, the result status
can be obtained using pg_wal_replay_wait_status() function.
Catversion is bumped.
Reported-by: Michael Paquier
Discussion: https://postgr.es/m/ZtUF17gF0pNpwZDI%40paquier.xyz
Reviewed-by: Pavel Borisov
Currently, WaitForLSNReplay() immediately throws an error if waiting for LSN
replay is not successful. This commit teaches WaitForLSNReplay() to return
the result of waiting, while making pg_wal_replay_wait() responsible for
throwing an appropriate error.
This is preparation to adding 'no_error' argument to pg_wal_replay_wait() and
new function pg_wal_replay_wait_status(), which returns the last wait result
status.
Additionally, we stop distinguishing situations when we find our instance to
be not in a recovery state before entering the waiting loop and inside
the waiting loop. Standby promotion may happen at any moment, even between
issuing a procedure call statement and pg_wal_replay_wait() doing a first
check of recovery status. Thus, there is no pointing distinguishing these
situations.
Also, since we may exit the waiting loop and see our instance not in recovery
without throwing an error, we need to deleteLSNWaiter() in that case. We do
this unconditionally for the sake of simplicity, even if standby was already
promoted after reaching the target LSN, the startup process surely already
deleted us.
Reported-by: Michael Paquier
Discussion: https://postgr.es/m/ZtUF17gF0pNpwZDI%40paquier.xyz
Reviewed-by: Michael Paquier, Pavel Borisov
3c5db1d6b implemented the pg_wal_replay_wait() stored procedure. Due to
the patch development history, the implementation resided in
src/backend/commands/waitlsn.c (src/include/commands/waitlsn.h for headers).
014f9f34d moved pg_wal_replay_wait() itself to
src/backend/access/transam/xlogfuncs.c near to the WAL-manipulation functions.
But most of the implementation stayed in place.
The code in src/backend/commands/waitlsn.c has nothing to do with commands,
but is related to WAL. So, this commit moves this code into
src/backend/access/transam/xlogwait.c (src/include/access/xlogwait.h for
headers).
Reported-by: Peter Eisentraut
Discussion: https://postgr.es/m/18c0fa64-0475-415e-a1bd-665d922c5201%40eisentraut.org
Reviewed-by: Pavel Borisov
Currently, when a single relcache entry gets invalidated,
TypeCacheRelCallback() has to loop over all type cache entries to find
appropriate typentry to invalidate. Unfortunately, using the syscache here
is impossible, because this callback could be called outside a transaction
and this makes impossible catalog lookups. This is why present commit
introduces RelIdToTypeIdCacheHash to map relation OID to its composite type
OID.
We are keeping RelIdToTypeIdCacheHash entry while corresponding type cache
entry have something to clean. Therefore, RelIdToTypeIdCacheHash shouldn't
get bloat in the case of temporary tables flood.
There are many places in lookup_type_cache() where syscache invalidation,
user interruption, or even error could occur. In order to handle this, we
keep an array of in-progress type cache entries. In the case of
lookup_type_cache() interruption this array is processed to keep
RelIdToTypeIdCacheHash in a consistent state.
Discussion: https://postgr.es/m/5812a6e5-68ae-4d84-9d85-b443176966a1%40sigaev.ru
Author: Teodor Sigaev
Reviewed-by: Aleksander Alekseev, Tom Lane, Michael Paquier, Roman Zharkov
Reviewed-by: Andrei Lepikhov, Pavel Borisov, Jian He, Alexander Lakhin
Reviewed-by: Artur Zakirov
Previously, a Query generated through the transform phase would have
unset stmt_location, tracking the starting point of a query string.
Extensions relying on the statement location to extract its relevant
parts in the source text string would fallback to use the whole
statement instead, leading to confusing results like in
pg_stat_statements for queries relying on nested queries, like:
- EXPLAIN, with top-level and nested query using the same query string,
and a query ID coming from the nested query when the non-top-level
entry.
- Multi-statements, with only partial portions of queries being
normalized.
- COPY TO with a query, SELECT or DMLs.
This patch improves things by keeping track of the statement locations
and propagate it to Query during transform, allowing PGSS to only show
the relevant part of the query for nested query. This leads to less
bloat in entries for non-top-level entries, as queries can now be
grouped within the same (toplevel, queryid) duos in pg_stat_statements.
The result gives a stricter one-one mapping between query IDs and its
query strings.
The regression tests introduced in 45e0ba30fc produce differences
reflecting the new logic.
Author: Anthonin Bonnefoy
Reviewed-by: Michael Paquier, Jian He
Discussion: https://postgr.es/m/CAO6_XqqM6S9bQ2qd=75W+yKATwoazxSNhv5sjW06fjGAtHbTUA@mail.gmail.com
Some buildfarm members complained about an always-true test in the
SOFT_ERROR_OCCURRED macro. Fix by reading the field directly rather
than using the macro.
Reported-by: Tom Lane
Discussion: https://postgr.es/m/2144895.1729653514@sss.pgh.pa.us
The proposed OAUTHBEARER SASL mechanism will need to allow larger
messages in the exchange, since tokens are sent directly by the
client. Move this limit into the pg_be_sasl_mech struct so that
it can be changed per-mechanism.
Author: Jacob Champion <jacob.champion@enterprisedb.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/CAOYmi+nqX_5=Se0W0Ynrr55Fha3CMzwv_R9P3rkpHb=1kG7ZTQ@mail.gmail.com
Enable manipulation of attribute statistics. Only superficial
validation is performed, so it's possible to add nonsense, and it's up
to the planner (or other users of statistics) to behave reasonably in
that case.
Bump catalog version.
Author: Corey Huinker
Discussion: https://postgr.es/m/CADkLM=eErgzn7ECDpwFcptJKOk9SxZEk5Pot4d94eVTZsvj3gw@mail.gmail.com
Previously, CREATE/ALTER EXTENSION gave basically no useful
context about errors reported while executing script files.
I think the idea was that you could run the same commands
manually to see the error, but that's often quite inconvenient.
Let's improve that.
If we get an error during raw parsing, we won't have a current
statement identified by a RawStmt node, but we should always get
a syntax error position. Show the portion of the script from
the last semicolon-newline before the error position to the first
one after it. There are cases where this might show only a
fragment of a statement, but that should be uncommon, and it
seems better than showing the whole script file.
Without an error cursor, if we have gotten past raw parsing (which
we probably have), we can report just the current SQL statement as
an item of error context.
In any case also report the script file name as error context,
since it might not be entirely obvious which of a series of
update scripts failed. We can also show an approximate script
line number in case whatever we printed of the query isn't
sufficiently identifiable.
The error-context code path is already exercised by some
test_extensions test cases, but add tests for the syntax-error
path.
Discussion: https://postgr.es/m/ZvV1ClhnbJLCz7Sm@msg.df7cb.de
Up to now, the parser's reporting of a statement's stmt_location
included any preceding whitespace or comments. This isn't really
desirable but was done to avoid accounting honestly for nonterminals
that reduce to empty. It causes problems for pg_stat_statements,
which partially compensates by manually stripping whitespace, but
is not bright enough to strip /*-style comments. There will be
more problems with an upcoming patch to improve reporting of errors
in extension scripts, so it's time to do something about this.
The thing we have to do to make it work right is to adjust
YYLLOC_DEFAULT to scan the inputs of each production to find the
first one that has a valid location (i.e., did not reduce to
empty). In theory this adds a little bit of per-reduction overhead,
but in practice it's negligible. I checked by measuring the time
to run raw_parser() on the contents of information_schema.sql, and
there was basically no change.
Having done that, we can rely on any nonterminal that didn't reduce
to completely empty to have a correct starting location, and we don't
need the kluges the stmtmulti production formerly used.
This should have a side benefit of allowing parse error reports to
include an error position in some cases where they formerly failed to
do so, due to trying to report the position of an empty nonterminal.
I did not go looking for an example though. The one previously known
case where that could happen (OptSchemaEltList) no longer needs the
kluge it had; but I rather doubt that that was the only case.
Discussion: https://postgr.es/m/ZvV1ClhnbJLCz7Sm@msg.df7cb.de
... to fix bugs when the referenced table is partitioned.
The catalog representation we chose for foreign keys connecting
partitioned tables (in commit f56f8f8da6) is inconvenient, in the
sense that a standalone table has a different way to represent the
constraint when referencing a partitioned table, than when the same
table becomes a partition (and vice versa). Because of this, we need to
create additional catalog rows on detach (pg_constraint and pg_trigger),
and remove them on attach. We were doing some of those things, but not
all of them, leading to missing catalog rows in certain cases.
The worst problem seems to be that we are missing action triggers after
detaching a partition, which means that you could update/delete rows
from the referenced partitioned table that still had referencing rows on
that table, the server failing to throw the required errors.
!!!
Note that this means existing databases with FKs that reference
partitioned tables might have rows that break relational integrity, on
tables that were once partitions on the referencing side of the FK.
Another possible problem is that trying to reattach a table
that had been detached would fail indicating that internal triggers
cannot be found, which from the user's point of view is nonsensical.
In branches 15 and above, we fix this by creating a new helper function
addFkConstraint() which is in charge of creating a standalone
pg_constraint row, and repurposing addFkRecurseReferencing() and
addFkRecurseReferenced() so that they're only the recursive routine for
each side of the FK, and they call addFkConstraint() to create
pg_constraint at each partitioning level and add the necessary triggers.
These new routines can be used during partition creation, partition
attach and detach, and foreign key creation. This reduces redundant
code and simplifies the flow.
In branches 14 and 13, we have a much simpler fix that consists on
simply removing the constraint on detach. The reason is that those
branches are missing commit f4566345cf, which reworked the way this
works in a way that we didn't consider back-patchable at the time.
We opted to leave branch 12 alone, because it's different from branch 13
enough that the fix doesn't apply; and because it is going in EOL mode
very soon, patching it now might be worse since there's no way to undo
the damage if it goes wrong.
Existing databases might need to be repaired.
In the future we might want to rethink the catalog representation to
avoid this problem, but for now the code seems to do what's required to
make the constraints operate correctly.
Co-authored-by: Jehan-Guillaume de Rorthais <jgdr@dalibo.com>
Co-authored-by: Tender Wang <tndrwang@gmail.com>
Co-authored-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Reported-by: Guillaume Lelarge <guillaume@lelarge.info>
Reported-by: Jehan-Guillaume de Rorthais <jgdr@dalibo.com>
Reported-by: Thomas Baehler (SBB CFF FFS) <thomas.baehler2@sbb.ch>
Discussion: https://postgr.es/m/20230420144344.40744130@karst
Discussion: https://postgr.es/m/20230705233028.2f554f73@karst
Discussion: https://postgr.es/m/GVAP278MB02787E7134FD691861635A8BC9032@GVAP278MB0278.CHEP278.PROD.OUTLOOK.COM
Discussion: https://postgr.es/m/18541-628a61bc267cd2d3@postgresql.org
If the query is rewritten into a NOTIFY command by a DO INSTEAD
rule, we'd get an assertion failure, or in non-assert builds
issue a rather confusing error message. Improve that.
Also fix a longstanding grammar mistake in a nearby error message.
Per bug #18664 from Alexander Lakhin. Back-patch to all supported
branches.
Tender Wang and Tom Lane
Discussion: https://postgr.es/m/18664-ffd0ebc2386598df@postgresql.org
The finished transaction list can contain XIDs that are older than the
serializable global xmin. It's a short-lived state;
ClearOldPredicateLocks() removes any such transactions from the list,
and it's called whenever the global xmin advances. But if another
backend calls SummarizeOldestCommittedSxact() in that window, it will
call SerialAdd() on an XID that's older than the global xmin, or if
there are no more transactions running, when global xmin is
invalid. That trips the assertion in SerialAdd().
Fixes bug #18658 reported by Andrew Bille. Thanks to Alexander Lakhin
for analysis. Backpatch to all versions.
Discussion: https://www.postgresql.org/message-id/18658-7dab125ec688c70b%40postgresql.org
The decision in b6e1157e7 to ignore raw_expr when evaluating a
JsonValueExpr was incorrect. While its value is not ultimately
used (since formatted_expr's value is), failing to initialize it
can lead to problems, for instance, when the expression tree in
raw_expr contains Aggref nodes, which must be initialized to
ensure the parent Agg node works correctly.
Also, optimize eval_const_expressions_mutator()'s handling of
JsonValueExpr a bit. Currently, when formatted_expr cannot be folded
into a constant, we end up processing it twice -- once directly in
eval_const_expressions_mutator() and again recursively via
ece_generic_processing(). This recursive processing is required to
handle raw_expr. To avoid the redundant processing of formatted_expr,
we now process raw_expr directly in eval_const_expressions_mutator().
Finally, update the comment of JsonValueExpr to describe the roles of
raw_expr and formatted_expr more clearly.
Bug: #18657
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Diagnosed-by: Fabio R. Sluzala <fabio3rs@gmail.com>
Diagnosed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18657-1b90ccce2b16bdb8@postgresql.org
Backpatch-through: 16
Make nbtree backwards scans optimistically access the next page to be
read to the left by following a prevPage block number that's now stashed
in currPos when the leaf page is first read. This approach matches the
one taken during forward scans, which follow a symmetric nextPage block
number from currPos. We stash both a prevPage and a nextPage, since the
scan direction might change (when fetching from a scrollable cursor).
Backwards scans will no longer need to lock the same page twice, except
in rare cases where the scan detects a concurrent page split (or page
deletion). Testing has shown this optimization to be particularly
effective during parallel index-only backwards scans: ~12% reductions in
query execution time are quite possible.
We're much better off being optimistic; concurrent left sibling page
splits are rare in general. It's possible that we'll need to lock more
pages than the pessimistic approach would have, but only when there are
_multiple_ concurrent splits of the left sibling page we now start at.
If there's just a single concurrent left sibling page split, the new
approach to scanning backwards will at least break even relative to the
old one (we'll acquire the same number of leaf page locks as before).
The optimization from this commit has long been contemplated by comments
added by commit 2ed5b87f96, which changed the rules for locking/pinning
during nbtree index scans. The approach that that commit introduced to
leaf level link traversal when scanning forwards is now more or less
applied all the time, regardless of the direction we're scanning in.
Following uniform conventions around sibling link traversal is simpler.
The only real remaining difference between our forward and backwards
handling is that our backwards handling must still detect and recover
from any concurrent left sibling splits (and concurrent page deletions),
as documented in the nbtree README. That is structured as a single,
isolated extra step that takes place in _bt_readnextpage.
Also use this opportunity to further simplify the functions that deal
with reading pages and traversing sibling links on the leaf level, and
to document their preconditions and postconditions (with respect to
things like buffer locks, buffer pins, and seizing the parallel scan).
This enhancement completely supersedes the one recently added by commit
3f44959f.
Author: Matthias van de Meent <boekewurm+postgres@gmail.com>
Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAEze2WgpBGRgTTxTWVPXc9+PB6fc1a7t+VyGXHzfnrFXcQVxnA@mail.gmail.com
Discussion: https://postgr.es/m/CAH2-WzkBTuFv7W2+84jJT8mWZLXVL0GHq2hMUTn6c9Vw=eYrCw@mail.gmail.com
The previous code (from commit 5d2e1cc117) did not detect end of
string correctly, so it would fail to error out if fewer than the
expected number of fields were present, which could then later lead to
a crash when NULL string pointers are accessed.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reported-by: Ranier Vilela <ranier.vf@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/79692bf9-17d3-41e6-b9c9-fc8c3944222a@eisentraut.org
Commit 3bf3ab8c56 initially introduced support for unlogged
materialized views, but this was later disallowed by commit 3223b25ff7.
Additionally, commit d25f519107 added more code for handling
unlogged materialized views. This commit cleans up all unused
code related to them.
If unlogged materialized views had been supported in any official
release, psql would need to retain code to handle them for compatibility
with older servers. However, since they were never included in
an official release, this code is no longer necessary.
Author: Pixian Shi
Reviewed-by: Yugo Nagata, Fujii Masao
Discussion: https://postgr.es/m/CAAccyYKRZ=OvAvgowiSH+OELbStLP=p2Ht=R3CgT=OaNSH5DAA@mail.gmail.com
After repartitioning the inner side of a hash join that would have
exceeded the allowed size, we check if all the tuples from a parent
partition moved to one child partition. That is evidence that it
contains duplicate keys and later attempts to repartition will also
fail, so we should give up trying to limit memory (for lack of a better
fallback strategy).
A thinko prevented the check from working correctly in partition 0 (the
one that is partially loaded into memory already). After
repartitioning, we should check for extreme skew if the *parent*
partition's space_exhausted flag was set, not the child partition's.
The consequence was repeated futile repartitioning until per-partition
data exceeded various limits including "ERROR: invalid DSA memory alloc
request size 1811939328", OS allocation failure, or temporary disk space
errors. (We could also do something about some of those symptoms, but
that's material for separate patches.)
This problem only became likely when PostgreSQL 16 introduced support
for Parallel Hash Right/Full Join, allowing NULL keys into the hash
table. Repartitioning always leaves NULL in partition 0, no matter how
many times you do it, because the hash value is all zero bits. That's
unlikely for other hashed values, but they might still have caused
wasted extra effort before giving up.
Back-patch to all supported releases.
Reported-by: Craig Milhiser <craig@milhiser.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Discussion: https://postgr.es/m/CA%2BwnhO1OfgXbmXgC4fv_uu%3DOxcDQuHvfoQ4k0DFeB0Qqd-X-rQ%40mail.gmail.com
Instead of using Node *, we can use an incomplete struct. That way,
everything has the correct type and fewer casts are required. This
technique is already used elsewhere in node type definitions.
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/637eeea8-5663-460b-a114-39572c0f6c6e%40eisentraut.org
adf97c156 made it so ExprStates could support hashing and changed Hash
Join to use that instead of manually extracting Datums from tuples and
hashing them one column at a time.
When hashing multiple columns or expressions, the code added in that
commit stored the intermediate hash value in the ExprState's resvalue
field. That was a mistake as steps may be injected into the ExprState
between each hashing step that look at or overwrite the stored
intermediate hash value. EEOP_PARAM_SET is an example of such a step.
Here we fix this by adding a new dedicated field for storing
intermediate hash values and adjust the code so that all apart from the
final hashing step store their result in the intermediate field.
In passing, rename a variable so that it's more aligned to the
surrounding code and also so a few lines stay within the 80 char margin.
Reported-by: Andres Freund
Reviewed-by: Alena Rybakina <a.rybakina@postgrespro.ru>
Discussion: https://postgr.es/m/CAApHDvqo9eenEFXND5zZ9JxO_k4eTA4jKMGxSyjdTrsmYvnmZw@mail.gmail.com
This commit adds missing checks for COPY FORCE_NOT_NULL and FORCE_NULL
when applied to all columns via "*". These options now correctly
require CSV mode and are disallowed in COPY TO, making their behavior
consistent with FORCE_QUOTE.
Some regression tests are added to verify the correct behavior for the
all-columns case, including FORCE_QUOTE, which was not tested.
Backpatch down to 17, where support for the all-column grammar with
FORCE_NOT_NULL and FORCE_NULL has been added.
Author: Joel Jacobson
Reviewed-by: Zhang Mingli
Discussion: https://postgr.es/m/65030d1d-5f90-4fa4-92eb-f5f50389858e@app.fastmail.com
Backpatch-through: 17
Commit 2dc1deaea turns out to have been still a brick shy of a load,
because CALL statements executing within a plpgsql exception block
could still pass the wrong snapshot to stable functions within the
CALL's argument list. That happened because standard_ProcessUtility
forces isAtomicContext to true if IsTransactionBlock is true, which
it always will be inside a subtransaction. Then ExecuteCallStmt
would think it does not need to push a new snapshot --- but
_SPI_execute_plan didn't do so either, since it thought it was in
nonatomic mode.
The best fix for this seems to be for _SPI_execute_plan to operate
in atomic execution mode if IsSubTransaction() is true, even when the
SPI context as a whole is non-atomic. This makes _SPI_execute_plan
have the same rules about when non-atomic execution is allowed as
_SPI_commit/_SPI_rollback have about when COMMIT/ROLLBACK are allowed,
which seems appropriately symmetric. (If anyone ever tries to allow
COMMIT/ROLLBACK inside a subtransaction, this would all need to be
rethought ... but I'm unconvinced that such a thing could be logically
consistent at all.)
For further consistency, also check IsSubTransaction() in
SPI_inside_nonatomic_context. That does not matter for its
one present-day caller StartTransaction, which can't be reached
inside a subtransaction. But if any other callers ever arise,
they'd presumably want this definition.
Per bug #18656 from Alexander Alehin. Back-patch to all
supported branches, like previous fixes in this area.
Discussion: https://postgr.es/m/18656-cade1780866ef66c@postgresql.org
Commit a4ccc1cef introduced the Generation Context and modified the
logical decoding process to use a Generation Context with a fixed
block size of 8MB for storing tuple data decoded during logical
decoding (i.e., rb->tup_context). Several reports have indicated that
the logical decoding process can be terminated due to
out-of-memory (OOM) situations caused by excessive memory usage in
rb->tup_context.
This issue can occur when decoding a workload involving several
concurrent transactions, including a long-running transaction that
modifies tuples. By design, the Generation Context does not free a
memory block until all chunks within that block are
released. Consequently, if tuples modified by the long-running
transaction are stored across multiple memory blocks, these blocks
remain allocated until the long-running transaction completes, leading
to substantial memory fragmentation. The memory usage during logical
decoding, tracked by rb->size, does not account for memory
fragmentation, resulting in potentially much higher memory consumption
than the value of the logical_decoding_work_mem parameter.
Various improvement strategies were discussed in the relevant
thread. This change reduces the block size of the Generation Context
used in rb->tup_context from 8MB to 8kB. This modification
significantly decreases the likelihood of substantial memory
fragmentation occurring and is relatively straightforward to
backport. Performance testing across multiple platforms has confirmed
that this change will not introduce any performance degradation that
would impact actual operation.
Backport to all supported branches.
Reported-by: Alex Richman, Michael Guissine, Avi Weinberg
Reviewed-by: Amit Kapila, Fujii Masao, David Rowley
Tested-by: Hayato Kuroda, Shlok Kyal
Discussion: https://postgr.es/m/CAD21AoBTY1LATZUmvSXEssvq07qDZufV4AF-OHh9VD2pC0VY2A%40mail.gmail.com
Backpatch-through: 12
Commit 5bf748b8 taught nbtree ScalarArrayOp index scans to decide when
and how to start the next primitive index scan based on physical index
characteristics. This included rules for deciding whether to start a
new primitive index scan (or whether to move onto the right sibling leaf
page instead) that specifically consider truncated lower-order columns
(-inf columns) from leaf page high keys.
These omitted columns were treated as satisfying the scan's required
scan keys, though only for scan keys marked required in the current scan
direction (forward). Scan keys that didn't get this behavior (those
marked required in the backwards direction only) usually didn't give the
scan reasonable cause to reposition itself to a later leaf page (via
another descent of the index in _bt_first), but _bt_advance_array_keys
would nevertheless always give up by forcing another call to _bt_first.
_bt_advance_array_keys was unwilling to allow the scan to continue onto
the next leaf page, to reconsider whether we really should start another
primitive scan based on the details of the sibling page's tuples. This
didn't match its behavior with similar cases involving keys required in
the current scan direction (forward), which seems unprincipled. It led
to an excessive number of primitive scans/index descents for queries
with a higher-order = array scan key (with dense, contiguous values)
mixed with a lower-order required > or >= scan key.
Bring > and >= strategy scan keys in line with other required scan key
types: treat truncated -inf scan keys as having satisfied scan keys
required in either scan direction (forwards and backwards alike) during
array advancement. That way affected scans can continue to the right
sibling leaf page. Advancement must now schedule an explicit recheck of
the right sibling page's high key in cases involving > or >= scan keys.
The recheck gives the scan a way to back out and start another primitive
index scan (we can't just rely on _bt_checkkeys with > or >= scan keys).
This work can be considered a stand alone optimization on top of the
work from commit 5bf748b8. But it was written in preparation for an
upcoming patch that will add skip scan to nbtree. In practice scans
that use "skip arrays" will tend to be much more sensitive to any
implementation deficiencies in this area.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CAH2-Wz=9A_UtM7HzUThSkQ+BcrQsQZuNhWOvQWK06PRkEp=SKQ@mail.gmail.com
Two near-identical copies of clause_sides_match_join() existed in
joinpath.c and analyzejoins.c. Deduplicate this by moving the function
into restrictinfo.h.
It isn't quite clear that keeping the inline property of this function
is worthwhile, but this commit is just an exercise in code
deduplication. More effort would be required to determine if the inline
property is worth keeping.
Author: James Hunter <james.hunter.pg@gmail.com>
Discussion: https://postgr.es/m/CAJVSvF7Nm_9kgMLOch4c-5fbh3MYg%3D9BdnDx3Dv7Fcb64zr64Q%40mail.gmail.com
This module provides SQL functions that allow to inspect logical
decoding components.
It currently allows to inspect the contents of serialized logical
snapshots of a running database cluster, which is useful for debugging
or educational purposes.
Author: Bertrand Drouvot
Reviewed-by: Amit Kapila, Shveta Malik, Peter Smith, Peter Eisentraut
Reviewed-by: David G. Johnston
Discussion: https://postgr.es/m/ZscuZ92uGh3wm4tW%40ip-10-97-1-34.eu-west-3.compute.internal
This commit moves the definitions of the SnapBuild and SnapBuildOnDisk
structs, related to logical snapshots, to the snapshot_internal.h
file. This change allows external tools, such as
pg_logicalinspect (with an upcoming patch), to access and utilize the
contents of logical snapshots.
Author: Bertrand Drouvot
Reviewed-by: Amit Kapila, Shveta Malik, Peter Smith
Discussion: https://postgr.es/m/ZscuZ92uGh3wm4tW%40ip-10-97-1-34.eu-west-3.compute.internal
The MergeJoin struct was tracking "mergeStrategies", which were an
array of btree strategy numbers, purely for the purpose of comparing
it later against btree strategies to determine if the scan direction
was forward or reverse. Change that. Instead, track
"mergeReversals", an array of bool, to indicate the same without an
unfortunate assumption that a strategy number refers specifically to a
btree strategy.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
Functions make_pathkey_from_sortop() and transformWindowDefinitions(),
which receive a SortGroupClause, were determining the sort order
(ascending vs. descending) by comparing that structure's operator
strategy to BTLessStrategyNumber, but could just as easily have gotten
it from the SortGroupClause object, if it had such a field, so add
one. This reduces the number of places that hardcode the assumption
that the strategy refers specifically to a btree strategy, rather than
some other index AM's operators.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
max_parallel_maintenance_workers has been introduced in 9da0cc3528,
and used a hardcoded limit of 1024 rather than this variable.
max_parallel_workers and max_parallel_workers_per_gather already used
MAX_PARALLEL_WORKER_LIMIT (1024) as their upper-bound since
6599c9ac33.
Author: Matthias van de Meent
Reviewed-by: Zhang Mingli
Discussion: https://postgr.es/m/CAEze2WiCiJD+8Wig_wGPyn4vgdPjbnYXy2Rw+9KYi6izTMuP=w@mail.gmail.com
find_computable_ec_member() had the wrong mental model of what
its primary caller prepare_sort_from_pathkeys() would do with
the selected EquivalenceClass member expression. We will not
compute the EC expression in a plan node atop the one returning
the passed-in targetlist; rather, the EC expression will be
computed as an additional column of that targetlist. So any
Var or quasi-Var used in the given tlist is also available to the
EC expression. In simple cases this makes no difference because
the given tlist is just a list of Vars or quasi-Vars --- but if
we are considering an appendrel member produced by flattening
a UNION ALL, the tlist may contain expressions, resulting in
failure to match and a "could not find pathkey item to sort"
error.
To fix, we can flatten both the tlist and the EC members with
pull_var_clause(), and then just check for subset-ness, so
that the code is actually shorter than before.
While this bug is quite old, the present patch only works back to
v13. We could possibly make it work in v12 by back-patching parts
of 375398244. On the whole though I don't like the risk/reward
ratio of that idea. v12's final release is next month, meaning
there would be no chance to correct matters if the patch causes a
regression. Since this failure has escaped notice for 14 years,
it's likely nobody will hit it in the field with v12.
Per bug #18652 from Alexander Lakhin.
Andrei Lepikhov and Tom Lane
Discussion: https://postgr.es/m/18652-deaa782ebcca85d1@postgresql.org
A missed check for the builtin collation provider could result in
falling through to call isalpha().
This does not appear to have practical consequences because it only
happens for characters in the ASCII range. Regardless, the builtin
provider should not be calling libc functions, so backpatch.
Discussion: https://postgr.es/m/1bd5a0a5192f82c22ee7527e825b18ab0028b2c7.camel@j-davis.com
Backpatch-through: 17
PostgreSQL has for a long time mixed two BIO implementations, which can
lead to subtle bugs and inconsistencies. This cleans up our BIO by just
just setting up the methods we need. This patch does not introduce any
functionality changes.
The following methods are no longer defined due to not being needed:
- gets: Not used by libssl
- puts: Not used by libssl
- create: Sets up state not used by libpq
- destroy: Not used since libpq use BIO_NOCLOSE, if it was used it close
the socket from underneath libpq
- callback_ctrl: Not implemented by sockets
The following methods are defined for our BIO:
- read: Used for reading arbitrary length data from the BIO. No change
in functionality from the previous implementation.
- write: Used for writing arbitrary length data to the BIO. No change
in functionality from the previous implementation.
- ctrl: Used for processing ctrl messages in the BIO (similar to ioctl).
The only ctrl message which matters is BIO_CTRL_FLUSH used for
writing out buffered data (or signal EOF and that no more data
will be written). BIO_CTRL_FLUSH is mandatory to implement and
is implemented as a no-op since there is no intermediate buffer
to flush.
BIO_CTRL_EOF is the out-of-band method for signalling EOF to
read_ex based BIO's. Our BIO is not read_ex based but someone
could accidentally call BIO_CTRL_EOF on us so implement mainly
for completeness sake.
As the implementation is no longer related to BIO_s_socket or calling
SSL_set_fd, methods have been renamed to reference the PGconn and Port
types instead.
This also reverts back to using BIO_set_data, with our fallback, as a small
optimization as BIO_set_app_data require the ex_data mechanism in OpenSSL.
Author: David Benjamin <davidben@google.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/CAF8qwaCZ97AZWXtg_y359SpOHe+HdJ+p0poLCpJYSUxL-8Eo8A@mail.gmail.com
This function returns the name, size, and last modification time of
each regular file in pg_wal/summaries. This allows administrators
to grant privileges to view the contents of this directory without
granting privileges on pg_ls_dir(), which allows listing the
contents of many other directories. This commit also gives the
pg_monitor predefined role EXECUTE privileges on the new
pg_ls_summariesdir() function.
Bumps catversion.
Author: Yushi Ogiwara
Reviewed-by: Michael Paquier, Fujii Masao
Discussion: https://postgr.es/m/a0a3af15a9b9daa107739eb45aa9a9bc%40oss.nttdata.com
c01743aa4 added EXPLAIN output to display the plan node's disabled_node
count whenever that count is above 0. Seemingly, there weren't many
people who liked that output as each parent of a disabled node would
also have a "Disabled Nodes" output due to the way disabled_nodes is
accumulated towards the root plan node. It was often hard and sometimes
impossible to figure out which nodes were disabled from looking at
EXPLAIN. You might think it would be possible to manually add up the
numbers from the "Disabled Nodes" output of a given node's children to
figure out if that node has a higher disabled_nodes count than its
children, but that wouldn't have worked for Append and Merge Append nodes
if some disabled child nodes were run-time pruned during init plan. Those
children are not displayed in EXPLAIN.
Here we attempt to improve this output by only showing "Disabled: true"
against only the nodes which are explicitly disabled themselves. That
seems to be the output that's desired by the most people who voiced
their opinion. This is done by summing up the disabled_nodes of the
given node's children and checking if that number is less than the
disabled_nodes of the current node.
This commit also fixes a bug in make_sort() which was neglecting to set
the Sort's disabled_nodes field. This should have copied what was done
in cost_sort(), but it hadn't been updated. With the new output, the
choice to not maintain that field properly was clearly wrong as the
disabled-ness of the node was attributed to the Sort's parent instead.
Reviewed-by: Laurenz Albe, Alena Rybakina
Discussion: https://postgr.es/m/9e4ad616bebb103ec2084bf6f724cfc739e7fabb.camel@cybertec.at
Commit 90189eefc1 narrowed pg_attribute.attinhcount and
pg_constraint.coninhcount from 32 to 16 bits, but kept other related
structs with 32-bit wide fields: ColumnDef and CookedConstraint contain
an int 'inhcount' field which is itself checked for overflow on
increments, but there's no check that the values aren't above INT16_MAX
before assigning to the catalog columns. This means that a creative
user can get a inconsistent table definition and override some
protections.
Fix it by changing those other structs to also use int16.
Also, modernize style by using pg_add_s16_overflow for overflow testing
instead of checking for negative values.
We also have Constraint.inhcount, which is here removed completely.
This was added by commit b0e96f3119 and not removed by its revert at
6f8bb7c1e9. It is not needed by the upcoming not-null constraints
patch.
This is mostly academic, so we agreed not to backpatch to avoid ABI
problems.
Bump catversion because of the changes to parse nodes.
Co-authored-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Co-authored-by: 何建 (jian he) <jian.universality@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/202410081611.up4iyofb5ie7@alvherre.pgsql
Commit 9391f7152 added a "PlannerInfo *root" parameter to
estimate_array_length, but failed to consider the possibility that
NULL would be passed for that, leading to a null pointer dereference.
We could rectify the particular case shown in the bug report by fixing
simplify_function/inline_function to pass through the root pointer.
However, as long as eval_const_expressions is documented to accept
NULL for root, similar hazards would remain. For now, let's just do
the narrow fix of hardening estimate_array_length to not crash.
Its behavior with NULL root will be the same as it was before
9391f7152, so this is not too awful.
Per report from Fredrik Widlert (via Paul Ramsey). Back-patch to v17
where 9391f7152 came in.
Discussion: https://postgr.es/m/518339E7-173E-45EC-A0FF-9A4A62AA4F40@cleverelephant.ca
The name extracted from the record of the GUC tables is applied to more
internal places of guc.c. This change has the advantage to simplify
parse_and_validate_value(), where the "name" was only used in elog
messages, while it was required to match with the name from the GUC
record.
pg_parameter_aclcheck() now passes the name of the GUC from its record
in two places rather than the caller's argument. The value given to
this function goes through convert_GUC_name_for_parameter_acl() that
does a simple ASCII downcasing.
Few GUCs mix character casing in core; one test is added for one of
these code paths with "IntervalStyle".
Author: Peter Smith, Michael Paquier
Discussion: https://postgr.es/m/ZwNh4vkc2NHJHnND@paquier.xyz
In some cases, we may want to transfer a HAVING clause into WHERE in
hopes of eliminating tuples before aggregation instead of after.
Previously, we couldn't do this if there were any nonempty grouping
sets, because we didn't have a way to tell if the HAVING clause
referenced any columns that were nullable by the grouping sets, and
moving such a clause into WHERE could potentially change the results.
Now, with expressions marked nullable by grouping sets with the RT
index of the RTE_GROUP RTE, it is much easier to identify those
clauses that reference any nullable-by-grouping-sets columns: we just
need to check if the RT index of the RTE_GROUP RTE is present in the
clause. For other HAVING clauses, they can be safely pushed down.
Author: Richard Guo
Discussion: https://postgr.es/m/CAMbWs4-NpzPgtKU=hgnvyn+J-GanxQCjrUi7piNzZ=upiCV=2Q@mail.gmail.com
For a mergejoin, if the given outer path or inner path is not already
well enough ordered, we need to do an explicit sort. Currently, we
only consider explicit full sort and do not account for incremental
sort.
In this patch, for the outer path of a mergejoin, we choose to use
explicit incremental sort if it is enabled and there are presorted
keys. For the inner path, though, we cannot use incremental sort
because it does not support mark/restore at present.
The rationale is based on the assumption that incremental sort is
always faster than full sort when there are presorted keys, a premise
that has been applied in various parts of the code. In addition, the
current cost model tends to favor incremental sort as being cheaper
than full sort in the presence of presorted keys, making it reasonable
not to consider full sort in such cases.
It could be argued that what if a mergejoin with an incremental sort
as the outer path is selected as the inner path of another mergejoin.
However, this should not be a problem, because mergejoin itself does
not support mark/restore either, and we will add a Material node on
top of it anyway in this case (see final_cost_mergejoin).
There is one ensuing plan change in the regression tests, and we have
to modify that test case to ensure that it continues to test what it
is intended to.
No backpatch as this could result in plan changes.
Author: Richard Guo
Reviewed-by: David Rowley, Tomas Vondra
Discussion: https://postgr.es/m/CAMbWs49x425QrX7h=Ux05WEnt8GS757H-jOP3_xsX5t1FoUsZw@mail.gmail.com
These fields can be set by executor nodes to record how many parallel
workers were planned to be launched and how many of them have been
actually launched within the number initially planned. This data is
able to give an approximation of the parallel worker draught a system
is facing, making easier the tuning of related configuration parameters.
These fields will be used by some follow-up patches to populate other
parts of the system with their data.
Author: Guillaume Lelarge, Benoit Lobréau
Discussion: https://postgr.es/m/783bc7f7-659a-42fa-99dd-ee0565644e25@dalibo.com
Discussion: https://postgr.es/m/CAECtzeWtTGOK0UgKXdDGpfTVSa5bd_VbUt6K6xn8P7X+_dZqKw@mail.gmail.com
AIO will need a resource owner to do IO. Right now we create a resowner
on-demand during basebackup, and we could do the same for AIO. But it seems
easier to just always create an aux process resowner.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/1f6b50a7-38ef-4d87-8246-786d39f46ab9@iki.fi
With real AIO it doesn't make sense to cross segment boundaries with one
IO. Add smgrmaxcombine() to allow upper layers to query which buffers can be
merged.
We could continue to cross segment boundaries when not using AIO, but it
doesn't really make sense, because md.c will never be able to perform the read
across the segment boundary in one system call. Which means we'll mark more
buffers as undergoing IO than really makes sense - if another backend desires
to read the same blocks, it'll be blocked longer than necessary. So it seems
better to just never cross the boundary.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/1f6b50a7-38ef-4d87-8246-786d39f46ab9@iki.fi
As pg_flush_data() doesn't do anything with fsync disabled, there's no point
in tracking the buffer for writeback. Arguably the better fix would be to
change pg_flush_data() to flush data even with fsync off, but that's a
behavioral change, whereas this is just a small optimization.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/1f6b50a7-38ef-4d87-8246-786d39f46ab9@iki.fi
This seems nicer than having to duplicate the logic between
InitProcess() and ProcKill() for which child processes have a
PMChildFlags slot.
Move the MarkPostmasterChildActive() call earlier in InitProcess(),
out of the section protected by the spinlock.
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/a102f15f-eac4-4ff2-af02-f9ff209ec66f@iki.fi
Commit 9e2d870119 placed the check for binary mode and on_error
before default values were inserted, which was not ideal.
This commit moves the check to a more appropriate position
after default values are set.
Additionally, the comment incorrectly mentioned two checks before
inserting defaults, when there are actually three. This commit corrects
that comment.
Author: Atsushi Torikoshi
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/8830518a-28ac-43a2-8a11-1676d9a3cdf8@oss.nttdata.com
Previously, when ON_ERROR was set to 'ignore', the COPY command
would skip all rows with data type conversion errors, with no way to
limit the number of skipped rows before failing.
This commit introduces the REJECT_LIMIT option, allowing users to
specify the maximum number of erroneous rows that can be skipped.
If more rows encounter data type conversion errors than allowed by
REJECT_LIMIT, the COPY command will fail with an error, even when
ON_ERROR = 'ignore'.
Author: Atsushi Torikoshi
Reviewed-by: Junwang Zhao, Kirill Reshke, jian he, Fujii Masao
Discussion: https://postgr.es/m/63f99327aa6b404cc951217fa3e61fe4@oss.nttdata.com
Several places treat MyStartTime as a "long", which is only 32 bits
wide on some platforms. In reality, MyStartTime is a pg_time_t,
i.e., a signed 64-bit integer. This will lead to interesting bugs
on the aforementioned systems in 2038 when signed 32-bit integers
are no longer sufficient to store Unix time (e.g., "pg_ctl start"
hanging). To fix, ensure that MyStartTime is handled as a 64-bit
value everywhere. (Of course, users will need to ensure that
time_t is 64 bits wide on their system, too.)
Co-authored-by: Max Johnson
Discussion: https://postgr.es/m/CO1PR07MB905262E8AC270FAAACED66008D682%40CO1PR07MB9052.namprd07.prod.outlook.com
Backpatch-through: 12
Commit 6aa44060a3 removed pg_authid's TOAST table because the only
varlena column is rolpassword, which cannot be de-TOASTed during
authentication because we haven't selected a database yet and
cannot read pg_class. Since that change, attempts to set password
hashes that require out-of-line storage will fail with a "row is
too big" error. This error message might be confusing to users.
This commit places a limit on the length of password hashes so that
attempts to set long password hashes will fail with a more
user-friendly error. The chosen limit of 512 bytes should be
sufficient to avoid "row is too big" errors independent of BLCKSZ,
but it should also be lenient enough for all reasonable use-cases
(or at least all the use-cases we could imagine).
Reviewed-by: Tom Lane, Jonathan Katz, Michael Paquier, Jacob Champion
Discussion: https://postgr.es/m/89e8649c-eb74-db25-7945-6d6b23992394%40gmail.com
During logical decoding of in-progress transactions, we perform the toast
table scan while fetching the default toast value for an attribute. We
forgot to initialize the flag during this scan to indicate that the system
table scan is in progress. We need this flag to ensure that during logical
decoding we never directly access the tableam or heap APIs because we check
for concurrent aborts only in systable_* APIs.
Reported-by: Alexander Lakhin
Author: Takeshi Ideriha, Hou Zhijie
Reviewed-by: Amit Kapila, Hou Zhijie
Backpatch-through: 14
Discussion: https://postgr.es/m/18641-6687273b7f15269d@postgresql.org
This GUC is written as camel-case in most of the documentation and the
GUC table (but not postgresql.conf.sample), and two error messages
hardcoded it with lower case characters. Let's use a style more
consistent.
Most of the noise comes from the regression tests, updated to reflect
the GUC name in these error messages.
Author: Peter Smith
Reviewed-by: Peter Eisentraut, Álvaro Herrera
Discussion: https://postgr.es/m/CAHut+Pv-kSN8SkxSdoHano_wPubqcg5789ejhCDZAcLFceBR-w@mail.gmail.com
pg_cursor() supposed that any Portal it finds in the hash table must
have sourceText set up, but there's an edge case where that is not so.
A newly-created Portal has sourceText = NULL, and that doesn't change
until PortalDefineQuery is called. In SPI_cursor_open_internal,
we perform GetCachedPlan between CreatePortal and PortalDefineQuery,
and it's possible for user-defined code to execute during that
planning and cause a fetch from the pg_cursors view, resulting in a
null-pointer-dereference crash. (It looks like the same could happen
in exec_bind_message, but I've not tried to provoke a failure there.)
I considered trying to fix this by setting sourceText sooner, but
there may be instances of this same calling pattern in extensions,
and we couldn't be sure they'd get the memo promptly. It seems
better to redefine pg_cursor as not showing Portals that have
not yet had PortalDefineQuery called on them, which we can do by
just skipping them if sourceText is still NULL.
(Before a1c692358, pg_cursor would instead return a row with NULL
in the statement column. We could revert to that behavior but it
doesn't really seem like a better definition, especially since our
documentation doesn't suggest that the column could be NULL.)
Per report from PetSerAl. Back-patch to all supported branches.
Discussion: https://postgr.es/m/CAKygsHTBXLXjwV43kpZa+Cs+XTiaeeJiZdL4cPBm9f4MTdw7wg@mail.gmail.com
When instantiating an existing partitioned index for a new child
partition, we use generateClonedIndexStmt to build a suitable
IndexStmt to pass to DefineIndex. However, when DefineIndex needs
to recurse to instantiate a newly created partitioned index on an
existing child partition, it was doing copyObject on the given
IndexStmt and then applying a bunch of ad-hoc fixups. This has
a number of problems, primarily that it implies fresh lookups of
referenced objects such as opclasses and collations. Since commit
2af07e2f7 caused DefineIndex to restrict search_path internally, those
lookups could fail or deliver different results than the original one.
We can avoid those problems and save a few dozen lines of code by
using generateClonedIndexStmt in this code path too.
Another thing this fixes is incorrect propagation of parent-index
comments to child indexes (because the copyObject approach copies
the idxcomment field while generateClonedIndexStmt doesn't). I had
noticed this in connection with commit c01eb619a, but not run the
problem to ground.
I'm tempted to back-patch this further than v17, but the only thing
it's known to fix in older branches is the comment issue, which is
pretty minor and doesn't seem worth the risk of introducing new
issues in stable branches. (If anyone does care about that,
clearing idxcomment in the copied IndexStmt would be a safer fix.)
Per bug #18637 from usamoi. Back-patch to v17 where the search_path
change came in.
Discussion: https://postgr.es/m/18637-f51e314546e3ba2a@postgresql.org
Commit bf03cfd1 started scanning all available BCP 47 locale names on
Windows. This caused an abort/crash in the Windows runtime library if
the default locale name contained non-ASCII characters, because of our
use of the setlocale() save/restore pattern with "char" strings. After
switching to another locale with a different encoding, the saved name
could no longer be understood, and setlocale() would abort.
"Turkish_Türkiye.1254" is the example from recent reports, but there are
other examples of countries and languages with non-ASCII characters in
their names, and they appear in Windows' (old style) locale names.
To defend against this:
1. In initdb, reject non-ASCII locale names given explicity on the
command line, or returned by the operating system environment with
setlocale(..., ""), or "canonicalized" by the operating system when we
set it.
2. In initdb only, perform the save-and-restore with Windows'
non-standard wchar_t variant of setlocale(), so that it is not subject
to round trip failures stemming from char string encoding confusion.
3. In the backend, we don't have to worry about the save-and-restore
problem because we have already vetted the defaults, so we just have to
make sure that CREATE DATABASE also rejects non-ASCII names in any new
databases. SET lc_XXX doesn't suffer from the problem, but the ban
applies to it too because it uses check_locale(). CREATE COLLATION
doesn't suffer from the problem either, but it doesn't use
check_locale() so it is not included in the new ban for now, to minimize
the change.
Anyone who encounters the new error message should either create a new
duplicated locale with an ASCII-only name using Windows Locale Builder,
or consider using BCP 47 names like "tr-TR". Users already couldn't
initialize a cluster with "Turkish_Türkiye.1254" on PostgreSQL 16+, but
the new failure mode is an error message that explains why, instead of a
crash.
Back-patch to 16, where bf03cfd1 landed. Older versions are affected
in theory too, but only 16 and later are causing crash reports.
Reviewed-by: Andrew Dunstan <andrew@dunslane.net> (the idea, not the patch)
Reported-by: Haifang Wang (Centific Technologies Inc) <v-haiwang@microsoft.com>
Discussion: https://postgr.es/m/PH8PR21MB3902F334A3174C54058F792CE5182%40PH8PR21MB3902.namprd21.prod.outlook.com
In the PostgreSQL C type naming schema, the type PageData should be
what the pointer of type Page points to. But in this case it's
actually an unrelated type local to generic_xlog.c. Rename that to a
more specific name. This makes room to possible add a PageData type
with the mentioned meaning, but this is not done here.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://www.postgresql.org/message-id/flat/001d457e-c118-4219-8132-e1846c2ae3c9%40eisentraut.org
Formerly there were two internal functions in numeric.c to perform
numeric division, div_var() and div_var_fast(). div_var() performed
division exactly to a specified rscale using Knuth's long division
algorithm, while div_var_fast() used the algorithm from the "FM"
library, which approximates each quotient digit using floating-point
arithmetic, and computes a truncated quotient with DIV_GUARD_DIGITS
extra digits. div_var_fast() could be many times faster than
div_var(), but did not guarantee correct results in all cases, and was
therefore only suitable for use in transcendental functions, where
small errors are acceptable.
This commit merges div_var() and div_var_fast() together into a single
function with an extra "exact" boolean parameter, which can be set to
false if the caller is OK with an approximate result. The new function
uses the faster algorithm from the "FM" library, except that when
"exact" is true, it does not truncate the computation with
DIV_GUARD_DIGITS extra digits, but instead performs the full-precision
computation, subtracting off complete multiples of the divisor for
each quotient digit. However, it is able to retain most of the
performance benefits of div_var_fast(), by delaying the propagation of
carries, allowing the inner loop to be auto-vectorized.
Since this may still lead to an inaccurate result, when "exact" is
true, it then inspects the remainder and uses that to adjust the
quotient, if necessary, to make it correct. In practice, the quotient
rarely needs to be adjusted, and never by more than one in the final
digit, though it's difficult to prove that, so the code allows for
larger adjustments, just in case.
In addition, use base-NBASE^2 arithmetic and a 64-bit dividend array,
similar to mul_var(), so that the number of iterations of the outer
loop is roughly halved. Together with the faster algorithm, this makes
div_var() up to around 20 times as fast as the old Knuth algorithm
when "exact" is true, and up to 2 or 3 times as fast as the old
div_var_fast() function when "exact" is false.
Dean Rasheed, reviewed by Joel Jacobson.
Discussion: https://postgr.es/m/CAEZATCVHR10BPDJSANh0u2+Sg6atO3mD0G+CjKDNRMD-C8hKzQ@mail.gmail.com
This assertion has been added by 24f5205948, but Alexander Lakhin has
proved that the ExecutorRun() one can be broken by using a PL function
that manipulates compute_query_id and track_activities, while the ones
in ExecutorFinish() and ExecutorEnd() could be triggered when cleaning
up portals at the beginning of a new query execution.
Discussion: https://postgr.es/m/b37d8e6c-e83d-e157-8865-1b2460a6aef2@gmail.com
If a MERGE command contains WHEN NOT MATCHED BY SOURCE actions, the
source relation appears on the outer side of the join. Thus, any Vars
referring to the source in the merge join condition, actions, and
RETURNING list should be marked as nullable by the join, since they
are used in the ModifyTable node above the join. Note that this only
applies to the copy of join condition used in the executor to
distinguish MATCHED from NOT MATCHED BY SOURCE cases. Vars in the
original join condition, inside the join node itself, should not be
marked.
Failure to correctly mark these Vars led to a "wrong varnullingrels"
error in the final stage of query planning, in some circumstances. We
happened to get away without this in all previous tests, since they
all involved a ModifyTable node directly on top of the join node, so
that the top plan targetlist coincided with the output of the join,
and the varnullingrels check was more lax. However, if another plan
node, such as a one-time filter Result node, gets inserted between the
ModifyTable node and the join node, then a stricter check is applied,
which fails.
Per bug #18634 from Alexander Lakhin. Thanks to Tom Lane and Richard
Guo for review and analysis.
Back-patch to v17, where WHEN NOT MATCHED BY SOURCE support was added
to MERGE.
Discussion: https://postgr.es/m/18634-db5299c937877f2b%40postgresql.org
If a MERGE command contains WHEN NOT MATCHED BY SOURCE actions, the
merge join condition is used by the executor to distinguish MATCHED
from NOT MATCHED BY SOURCE cases. However, this qual is executed using
the output from the join subplan node, which nulls the output from the
source relation in the not matched case, and so the result may be
incorrect if the join condition is "non-strict" -- for example,
something like "src.col IS NOT DISTINCT FROM tgt.col".
Fix this by enhancing the join recheck condition with an additional
"src IS NOT NULL" check, so that it does the right thing when
evaluated using the output from the join subplan.
Noted by Tom Lane while investigating bug #18634 from Alexander
Lakhin.
Back-patch to v17, where WHEN NOT MATCHED BY SOURCE support was added
to MERGE.
Discussion: https://postgr.es/m/18634-db5299c937877f2b%40postgresql.org
This commit simplifies CopyFrom() by removing the unnecessary local variable
'skipped', which tracked the number of rows skipped due to on_error = 'ignore'.
That count is already handled by cstate->num_errors, so the 'skipped' variable
was redundant.
Additionally, the condition on_error != COPY_ON_ERROR_STOP is removed.
Since on_error == COPY_ON_ERROR_IGNORE is already checked, and on_error
only has two values (ignore and stop), the additional check was redundant
and made the logic harder to read. Seemingly this was introduced
in preparation for a future patch, but the current checks don’t offer
clear value and have been removed to improve readability.
Author: Atsushi Torikoshi
Reviewed-by: Masahiko Sawada, Fujii Masao
Discussion: https://postgr.es/m/ab59dad10490ea3734cf022b16c24cfd@oss.nttdata.com
Previously, when the on_error option was set to ignore, the COPY command
would always log NOTICE messages for input rows discarded due to
data type incompatibility. Users had no way to suppress these messages.
This commit introduces a new log_verbosity setting, 'silent',
which prevents the COPY command from emitting NOTICE messages
when on_error = 'ignore' is used, even if rows are discarded.
This feature is particularly useful when processing malformed files
frequently, where a flood of NOTICE messages can be undesirable.
For example, when frequently loading malformed files via the COPY command
or querying foreign tables using file_fdw (with an upcoming patch to
add on_error support for file_fdw), users may prefer to suppress
these messages to reduce log noise and improve clarity.
Author: Atsushi Torikoshi
Reviewed-by: Masahiko Sawada, Fujii Masao
Discussion: https://postgr.es/m/ab59dad10490ea3734cf022b16c24cfd@oss.nttdata.com
This commit addresses two issues related to the manipulation of the
partition constraint expression list in ATExecAttachPartition().
First, the current use of list_concat() to combine the partition's
constraint (retrieved via get_qual_from_partbound()) with the parent
table’s partition constraint can lead to memory safety issues. After
calling list_concat(), the original constraint (partBoundConstraint)
might no longer be safe to access, as list_concat() may free or modify
it.
Second, there's a logical error in constructing the constraint for
validating against the default partition. The current approach
incorrectly includes a negated version of the parent table's partition
constraint, which is redundant, as it always evaluates to false for
rows in the default partition.
To resolve these issues, list_concat() is replaced with
list_concat_copy(), ensuring that partBoundConstraint remains unchanged
and can be safely reused when constructing the validation constraint
for the default partition.
This fix is not applied to back-branches, as there is no live bug and
the issue has not caused any reported problems in practice.
Nitin Jadhav posted a patch to address the memory safety issue, but I
decided to follow Alvaro Herrera's suggestion from the initial
discussion, as it allows us to fix both the memory safety and logical
issues.
Reported-by: Andres Freund <andres@anarazel.de>
Reported-by: Nitin Jadhav <nitinjadhavpostgres@gmail.com>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Discussion: https://postgr.es/m/20231115165737.zeulb575cgrbqo74@awork3.anarazel.de
Discussion: https://postgr.es/m/CAMm1aWbmYHM3bqtjyMQ-a+4Ub=dgsb_2E3_up2cn=UGdHNrGTg@mail.gmail.com
The following commands were allowed on partitioned tables, with
different effects:
1) ALTER TABLE SET [UN]LOGGED did not issue an error, and did not update
pg_class.relpersistence.
2) CREATE UNLOGGED TABLE was working with pg_class.relpersistence marked
as initially defined, but partitions did not inherit the UNLOGGED
property, which was confusing.
This commit causes the commands mentioned above to fail for partitioned
tables, instead.
pg_dump is tweaked so as partitioned tables marked as UNLOGGED ignore
the option when dumped from older server versions. pgbench needs a
tweak for --unlogged and --partitions=N to ignore the UNLOGGED option on
the partitioned tables created, its partitions still being unlogged.
Author: Michael Paquier
Reviewed-by: Nathan Bossart
Discussion: https://postgr.es/m/ZiiyGFTBNkqcMQi_@paquier.xyz
Previously, the pg_stat_checkpointer view and the checkpoint completion
log message could show different numbers for buffers written
during checkpoints. The view only counted shared buffers,
while the log message included both shared and SLRU buffers,
causing inconsistencies.
This commit resolves the issue by updating both the view and the log message
to separately report shared and SLRU buffers written during checkpoints.
A new slru_written column is added to the pg_stat_checkpointer view
to track SLRU buffers, while the existing buffers_written column now
tracks only shared buffers. This change would help users distinguish
between the two types of buffers, in the pg_stat_checkpointer view and
the checkpoint complete log message, respectively.
Bump catalog version.
Author: Nitin Jadhav
Reviewed-by: Bharath Rupireddy, Michael Paquier, Kyotaro Horiguchi, Robert Haas
Reviewed-by: Andres Freund, vignesh C, Fujii Masao
Discussion: https://postgr.es/m/CAMm1aWb18EpT0whJrjG+-nyhNouXET6ZUw0pNYYAe+NezpvsAA@mail.gmail.com
We have always documented that a copy EOF marker (\.) must appear
by itself on a line, and that is how psql interprets the rule.
However, the backend's actual COPY FROM logic only insists that
there not be data between the \. and the following newline.
Any data ahead of the \. is parsed as a final line of input.
It's hard to interpret this as anything but an ancient mistake
that we've faithfully carried forward. Continuing to allow it
is not cost-free, since it could mask client-side bugs that
unnecessarily backslash-escape periods (and thereby risk
accidentally creating an EOF marker). So, let's remove that
provision and throw error if the EOF marker isn't alone on its
line, matching what the documentation has said right along.
Adjust the relevant error messages to be clearer, too.
Discussion: https://postgr.es/m/ed659f37-a9dd-42a7-82b9-0da562cc4006@manitou-mail.org
Refactoring in the interest of code consistency, a follow-up to 2e068db56e.
The argument against inserting a special enum value at the end of the enum
definition is that a switch statement might generate a compiler warning unless
it has a default clause.
Aleksander Alekseev, reviewed by Michael Paquier, Dean Rasheed, Peter Eisentraut
Discussion: https://postgr.es/m/CAJ7c6TMsiaV5urU_Pq6zJ2tXPDwk69-NKVh4AMN5XrRiM7N%2BGA%40mail.gmail.com
LLVM's opaque pointer change began in LLVM 14, but remained optional
until LLVM 16. When commit 37d5babb added opaque pointer support, we
didn't turn it on for LLVM 14 and 15 yet because we didn't want to risk
weird bitcode incompatibility problems in released branches of
PostgreSQL. (That might have been overly cautious, I don't know.)
Now that PostgreSQL 18 has dropped support for LLVM versions < 14, and
since it hasn't been released yet and no extensions or bitcode have been
built against it in the wild yet, we can be more aggressive. We can rip
out the support code and build system clutter that made opaque pointer
use optional.
Author: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussions: https://postgr.es/m/CA%2BhUKGLhNs5geZaVNj2EJ79Dx9W8fyWUU3HxcpZy55sMGcY%3DiA%40mail.gmail.com
COMMIT PREPARED removes on-disk 2PC files near its end, but the state
checked if a file is on-disk or not gets read from shared memory while
not holding the two-phase state lock.
Because of that, there was a small window where a second backend doing a
PREPARE TRANSACTION could reuse the GlobalTransaction put back into the
2PC free list by the COMMIT PREPARED, overwriting the "ondisk" flag read
afterwards by the COMMIT PREPARED to decide if its on-disk two-phase
state file should be removed, preventing the file deletion.
This commit fixes this issue so as the "ondisk" flag in the
GlobalTransaction is read while holding the two-phase state lock, not
from shared memory after its entry has been added to the free list.
Orphaned two-phase state files flushed to disk after a checkpoint are
discarded at the beginning of recovery. However, a truncation of
pg_xact/ would make the startup process issue a FATAL when it cannot
read the SLRU page holding the state of the transaction whose 2PC file
was orphaned, which is a necessary step to decide if the 2PC file should
be removed or not. Removing manually the file would be necessary in
this case.
Issue introduced by effe7d9552, so backpatch all the way down.
Mea culpa.
Author: wuchengwen
Discussion: https://postgr.es/m/tencent_A7F059B5136A359625C7B2E4A386B3C3F007@qq.com
Backpatch-through: 12
As formulated, the assertion added in the executor by 24f5205948 to
check that a query ID is set had two problems:
- track_activities may be disabled while compute_query_id is enabled,
causing the query ID to not be reported to pg_stat_activity.
- debug_query_string may not be set in some context. The only path
where this would matter is visibly autovacuum, should parallel workers
be enabled there at some point. This is not the case currently.
There was no test showing the interactions between the query ID and
track_activities, so let's add one based on a scan of pg_stat_activity.
This assertion is still an experimentation at this stage, but let's see
if this shows more paths where query IDs are not properly set while they
should.
Discussion: https://postgr.es/m/Zvn5616oYXmpXyHI@paquier.xyz
The comment in pg_class_aclmask_ext() which lists the allowed commands
for the pg_maintain role lacked LOCK TABLE.
Reported-by: Yusuke Sugie <btsugieyuusuke@oss.nttdata.com>
Reviewed-by: Yugo Nagata <nagata@sraoss.co.jp>
Discussion: https://postgr.es/m/034d3c60f5daba1919cd90f236b2e22d@oss.nttdata.com
Since backslash is (typically) not special in CSV data, we should
not be treating \. as special either. The server historically did
this to keep CSV and TEXT modes more alike and to support V2 protocol;
but V2 protocol is long dead, and the inconsistency with CSV standards
is annoying. Remove that behavior in CopyReadLineText, and make some
minor consequent code simplifications.
On the client side, we need to fix psql so that it does not check
for \. except when reading data from STDIN (that is, the script
source). We must do that regardless of TEXT/CSV mode or there is
no way to end the COPY short of script EOF. Also, be careful
not to send the \. to the server in that case.
This is a small compatibility break in that other applications
beside psql may need similar adjustment. Also, using an older
version of psql with a v18 server may result in misbehavior
during CSV-mode COPY IN.
Daniel Vérité, reviewed by vignesh C, Robert Haas, and myself
Discussion: https://postgr.es/m/ed659f37-a9dd-42a7-82b9-0da562cc4006@manitou-mail.org
This restriction seems to have come about due to some fuzzy thinking: in
commit 9139aa1942 we were adding a restriction against ADD constraint
ONLY on partitioned tables (which is sensible) and apparently we thought
the DROP case had to be symmetrical. However, it isn't, and the
comments about it are mistaken about the effect it would have. Remove
this limitation.
There have been no reports of users bothered by this limitation, so I'm
not backpatching it just yet. We can revisit this decision later, as needed.
Reviewed-by: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/202409261752.nbvlawkxsttf@alvherre.pgsql
Discussion: https://postgr.es/m/7682253a-6f79-6a92-00aa-267c4c412870@lab.ntt.co.jp
(about commit 9139aa1942, previously not registered)
This is a continuation of work like 11c34b342b, done to reduce the
bloat of pg_stat_statements by applying more normalization to query
entries. This commit is able to detect and normalize values in
VariableSetStmt, resulting in:
SET conf_param = $1
Compared to other parse nodes, VariableSetStmt is embedded in much more
places in the parser, impacting many query patterns in
pg_stat_statements. A custom jumble function is used, with an extra
field in the node to decide if arguments should be included in the
jumbling or not, a location field being not enough for this purpose.
This approach allows for a finer tuning.
Clauses relying on one or more keywords are not normalized, for example:
* DEFAULT
* FROM CURRENT
* List of keywords. SET SESSION CHARACTERISTICS AS TRANSACTION,
where it is critical to differentiate different sets of options, is a
good example of why normalization should not happen.
Some queries use VariableSetStmt for some subclauses with SET, that also
have their values normalized:
- ALTER DATABASE
- ALTER ROLE
- ALTER SYSTEM
- CREATE/ALTER FUNCTION
ba90eac7a9 has added test coverage for most of the existing SET
patterns. The expected output of these tests shows the difference this
commit creates. Normalization could be perhaps applied to more portions
of the grammar but what is done here is conservative, and good enough as
a starting point.
Author: Greg Sabino Mullane, Michael Paquier
Discussion: https://postgr.es/m/36e5bffe-e989-194f-85c8-06e7bc88e6f7@amazon.com
Discussion: https://postgr.es/m/B44FA29D-EBD0-4DD9-ABC2-16F1CB087074@amazon.com
Discussion: https://postgr.es/m/CAKAnmmJtJY2jzQN91=2QAD2eAJAA-Per61eyO48-TyxEg-q0Rg@mail.gmail.com
Checkpoints can be skipped when the server is idle. The existing num_timed and
num_requested counters in pg_stat_checkpointer track both completed and
skipped checkpoints, but there was no way to count only the completed ones.
This commit introduces the num_done counter, which tracks only completed
checkpoints, making it easier to see how many were actually performed.
Bump catalog version.
Author: Anton A. Melnikov
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/9ea77f40-818d-4841-9dee-158ac8f6e690@oss.nttdata.com
All these code paths use their own entry point when starting parallel
workers, but failed to set a query ID, even if they set a text query.
Hence, this data would be missed in pg_stat_activity for the worker
processes. The main entry point for parallel query processing,
ParallelQueryMain(), is already doing that by saving its query ID in a
dummy PlannedStmt, but not the others. The code is changed so as the
query ID of these queries is set in their shared state, and reported
back once the parallel workers start.
Some tests are added to show how the failures can happen for btree and
BRIN with a parallel build enforced, which are able to trigger a failure
in an assertion added by 24f5205948 in the recovery TAP test
027_stream_regress.pl where pg_stat_statements is always loaded. In
this case, the executor path was taken because the index expression
needs to be flattened when building its IndexInfo.
Alexander Lakhin has noticed the problem in btree, and I have noticed
that the issue was more spread. This is arguably a bug, but nobody has
complained about that until now, so no backpatch is done out of caution.
If folks would like to see a backpatch, well, let me know.
Reported-by: Alexander Lakhin
Reviewed-by: Sami Imseih
Discussion: https://postgr.es/m/cf3547c1-498a-6a61-7b01-819f902a251f@gmail.com
Up to now, remove_rel_from_query() has done a pretty shoddy job
of updating our where-needed bitmaps (per-Var attr_needed and
per-PlaceHolderVar ph_needed relid sets). It removed direct mentions
of the to-be-removed baserel and outer join, which is the minimum
amount of effort needed to keep the data structures self-consistent.
But it didn't account for the fact that the removed join ON clause
probably mentioned Vars of other relations, and those Vars might now
not be needed as high up in the join tree as before. It's easy to
show cases where this results in failing to remove a lower outer join
that could also have been removed.
To fix, recalculate the where-needed bitmaps from scratch after
each successful join removal. This sounds expensive, but it seems
to add only negligible planner runtime. (We cheat a little bit
by preserving "relation 0" entries in the bitmaps, allowing us to
skip re-scanning the targetlist and HAVING qual.)
The submitted test case drew attention because we had successfully
optimized away the lower join prior to v16. I suspect that that's
somewhat accidental and there are related cases that were never
optimized before and now can be. I've not tried to come up with
one, though.
Perhaps we should back-patch this into v16 and v17 to repair the
performance regression. However, since it took a year for anyone
to notice the problem, it can't be affecting too many people. Let's
let the patch bake awhile in HEAD, and see if we get more complaints.
Per bug #18627 from Mikaël Gourlaouen. No back-patch for now.
Discussion: https://postgr.es/m/18627-44f950eb6a8416c2@postgresql.org
An invalid toast index is skipped in reindex_relation(). These would be
remnants of a failed REINDEX CONCURRENTLY and they should never been
rebuilt as there can only be one valid toast index at a time.
REINDEX_REL_SUPPRESS_INDEX_USE, used by CLUSTER and VACUUM FULL, needs
to maintain a list of the indexes being processed. The list of indexes
is retrieved from the relation cache, and includes invalid indexes. The
code has missed that invalid toast indexes are ignored in
reindex_relation() as this leads to a hard failure in reindex_index(),
and they were left in the reindex pending list, making the list
inconsistent when rechecked. The incorrect memory access was happening
when scanning pg_class for the refresh of pg_database.datfrozenxid, when
doing a scan of pg_class.
This issue exists since REINDEX CONCURRENTLY exists, where invalid toast
indexes can exist, so backpatch all the way down.
Reported-by: Alexander Lakhin
Author: Tender Wang
Discussion: https://postgr.es/m/18630-9aed99c38830657d@postgresql.org
Backpatch-through: 12
Creating, reindexing, and dropping an index concurrently could
entail accessing pg_index's TOAST table, which was recently added
in commit b52c4fc3c0. These code paths start and commit their own
transactions, but they do not always set an active snapshot. This
rightfully leads to assertion failures and ERRORs when trying to
access pg_index's TOAST table, such as the following:
ERROR: cannot fetch toast data without an active snapshot
To fix, push an active snapshot just before each section of code
that might require accessing pg_index's TOAST table, and pop it
shortly afterwards.
Reported-by: Alexander Lakhin
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/a97d7401-e7c9-f771-6a00-037379f0a8bb%40gmail.com
int_to_roman() only accepts plain "int" input, which is fine since
we're going to produce '###############' for any value above 3999
anyway. However, the numeric and int8 variants of to_char() would
throw an error if the given input exceeded the integer range, while
the float-input variants invoked undefined-per-C-standard behavior.
Fix things so that you uniformly get '###############' for out of
range input.
Also add test cases covering this code, plus the equally-untested
EEEE, V, and PL format codes.
Discussion: https://postgr.es/m/2956175.1725831136@sss.pgh.pa.us
The unwritten assumption of this code is that both events->head and
events->tail are NULL together (an empty list) or they aren't. So the
code was testing events->head for nullness and using that as a cue to
deference events->tail, which annoys the Svace static code analyzer.
We can silence it by testing events->tail member instead, and add an
assertion about events->head to ensure it's all consistent.
This code is very old and as far as we know, there's never been a bug
report related to this, so there's no need to backpatch.
This was found by the ALT Linux Team using Svace.
Author: Alexander Kuznetsov <kuznetsovam@altlinux.org>
Discussion: https://postgr.es/m/6d0323c3-3f5d-4137-af73-98a5ab90e77c@altlinux.org
The previous commit fixed some ways of losing an inplace update. It
remained possible to lose one when a backend working toward a
heap_update() copied a tuple into memory just before inplace update of
that tuple. In catalogs eligible for inplace update, use LOCKTAG_TUPLE
to govern admission to the steps of copying an old tuple, modifying it,
and issuing heap_update(). This includes MERGE commands. To avoid
changing most of the pg_class DDL, don't require LOCKTAG_TUPLE when
holding a relation lock sufficient to exclude inplace updaters.
Back-patch to v12 (all supported versions). In v13 and v12, "UPDATE
pg_class" or "UPDATE pg_database" can still lose an inplace update. The
v14+ UPDATE fix needs commit 86dc90056d,
and it wasn't worth reimplementing that fix without such infrastructure.
Reviewed by Nitin Motiani and (in earlier versions) Heikki Linnakangas.
Discussion: https://postgr.es/m/20231027214946.79.nmisch@google.com
As previously-added tests demonstrated, heap_inplace_update() could
instead update an unrelated tuple of the same catalog. It could lose
the update. Losing relhasindex=t was a source of index corruption.
Inplace-updating commands like VACUUM will now wait for heap_update()
commands like GRANT TABLE and GRANT DATABASE. That isn't ideal, but a
long-running GRANT already hurts VACUUM progress more just by keeping an
XID running. The VACUUM will behave like a DELETE or UPDATE waiting for
the uncommitted change.
For implementation details, start at the systable_inplace_update_begin()
header comment and README.tuplock. Back-patch to v12 (all supported
versions). In back branches, retain a deprecated heap_inplace_update(),
for extensions.
Reported by Smolkin Grigory. Reviewed by Nitin Motiani, (in earlier
versions) Heikki Linnakangas, and (in earlier versions) Alexander
Lakhin.
Discussion: https://postgr.es/m/CAMp+ueZQz3yDk7qg42hk6-9gxniYbp-=bG2mgqecErqR5gGGOA@mail.gmail.com
The current use always releases this locktag. A planned use will
continue that intent. It will involve more areas of code, making unlock
omissions easier. Warn under debug_assertions, like we do for various
resource leaks. Back-patch to v12 (all supported versions), the plan
for the commit of the new use.
Reviewed by Heikki Linnakangas.
Discussion: https://postgr.es/m/20240512232923.aa.nmisch@google.com
Ensure that error paths within these functions do not leak a collator,
and return the result rather than using an out parameter. (Error paths
in the caller may still result in a leaked collator, which will be
addressed separately.)
In make_libc_collator(), if the first newlocale() succeeds and the
second one fails, close the first locale_t object.
The function make_icu_collator() doesn't have any external callers, so
change it to be static.
Discussion: https://postgr.es/m/54d20e812bd6c3e44c10eddcd757ec494ebf1803.camel@j-davis.com
When our XML-handling modules were first written, the SQL standard
lacked any error codes that were particularly intended for XML
error conditions. Unsurprisingly, this led to some rather random
choices of errcodes in those modules. Now the standard has a whole
SQLSTATE class, "Class 10 - XQuery Error", with a reasonably large
selection of relevant-looking errcodes.
In this patch I've chosen one fairly generic code defined by the
standard, 10608 = invalid_argument_for_xquery, and used it where
it seemed appropriate. I've also made an effort to replace
ERRCODE_INTERNAL_ERROR everywhere it was not clearly reporting
a coding problem; in particular, many of the existing uses look
like they can fairly be reported as ERRCODE_OUT_OF_MEMORY.
It might be interesting to try to map libxml2's error codes into
the standard's new collection, but I've not undertaken that here.
Discussion: https://postgr.es/m/417250.1726341268@sss.pgh.pa.us
The array->scan_key references fixed up at the end of preprocessing
start out as offsets into the arrayKeyData[] array (the array returned
by _bt_preprocess_array_keys at the start of preprocessing that involves
array scan keys). Offsets into the arrayKeyData[] array are no longer
guaranteed to be valid offsets into our original scan->keyData[] input
scan key array, but comments describing the array->scan_key references
still talked about scan->keyData[]. Update those comments.
Oversight in commit b5249741.
Since autovacuum does not trigger an ANALYZE for partitioned tables,
users must perform these manually. However, performing a manual ANALYZE
on a partitioned table would always result in recursively analyzing each
partition and that could be undesirable as autovacuum takes care of that.
For partitioned tables that contain a large number of partitions, having
to analyze each partition could take an unreasonably long time, especially
so for tables with a large number of columns.
Here we allow the ONLY keyword to prefix the name of the table to allow
users to have ANALYZE skip processing partitions. This option can also
be used with VACUUM, but there is no work to do if VACUUM ONLY is used on
a partitioned table.
This commit also changes the behavior of VACUUM and ANALYZE for
inheritance parents. Previously inheritance child tables would not be
processed when operating on the parent. Now, by default we *do* operate
on the child tables. ONLY can be used to obtain the old behavior.
The release notes should note this as an incompatibility. The default
behavior has not changed for partitioned tables as these always
recursively processed the partitions.
Author: Michael Harris <harmic@gmail.com>
Discussion: https://postgr.es/m/CADofcAWATx_haD=QkSxHbnTsAe6+e0Aw8Eh4H8cXyogGvn_kOg@mail.gmail.com
Discussion: https://postgr.es/m/CADofcAXVbD0yGp_EaC9chmzsOoSai3jcfBCnyva3j0RRdRvMVA@mail.gmail.com
Reviewed-by: Jelte Fennema-Nio <postgres@jeltef.nl>
Reviewed-by: Melih Mutlu <m.melihmutlu@gmail.com>
Reviewed-by: Atsushi Torikoshi <torikoshia@oss.nttdata.com>
Reviewed-by: jian he <jian.universality@gmail.com>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Attempting these commands for a non-partitioned table would result in a
failure when creating the relation in transformPartitionCmd(). This
gives the possibility to throw an error earlier with a much better error
message, thanks to d69a3f4d70.
The extra test cases are from me. Note that FINALIZE uses a different
subcommand and it had no coverage for its failure path with
non-partitioned tables.
Author: Álvaro Herrera, Michael Paquier
Reviewed-by: Nathan Bossart
Discussion: https://postgr.es/m/202409190803.tnis52adt2n5@alvherre.pgsql
Commit c4d5cb71d2 introduced a couple asserts in the fast-path locking
code, upsetting Coverity.
The assert in InitProcGlobal() is clearly wrong, as it assigns instead
of checking the value. This is harmless, but doesn't check anything.
The asserts in FAST_PATH_ macros are written as if for signed values,
but the macros are only called for unsigned ones. That makes the check
for (val >= 0) useless. Checks written as ((uint32) x < max) work for
both signed and unsigned values. Negative values should wrap to values
greater than INT32_MAX.
Per Coverity, report by Tom Lane.
Reported-by: Tom Lane
Discussion: https://postgr.es/m/2891628.1727019959@sss.pgh.pa.us
This commit is similar to 95d6e9af07, expanding the idea to CTE scan,
table function scan and recursive union scan nodes so that the maximum
tuplestore memory or disk usage is shown with EXPLAIN ANALYZE command.
Also adjust show_storage_info() so that it accepts storage type and
storage size arguments instead of Tuplestorestate. This allows the
node types to share the formatting code using show_storage_info(). Due
to this show_material_info() and show_windowagg_info() are also
modified.
Reviewed-by: David Rowley
Discussion: https://postgr.es/m/20240918.211246.1127161704188186085.ishii%40postgresql.org
pg_authid's only varlena column is rolpassword, which unfortunately
cannot be de-TOASTed during authentication because we haven't
selected a database yet and cannot read pg_class. By removing
pg_authid's TOAST table, attempts to set password hashes that
require out-of-line storage will fail with a "row is too big"
error instead. We may want to provide a more user-friendly error
in the future, but for now let's just remove the useless TOAST
table.
Bumps catversion.
Reported-by: Alexander Lakhin
Reviewed-by: Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/89e8649c-eb74-db25-7945-6d6b23992394%40gmail.com
Replace the fixed-size array of fast-path locks with arrays, sized on
startup based on max_locks_per_transaction. This allows using fast-path
locking for workloads that need more locks.
The fast-path locking introduced in 9.2 allowed each backend to acquire
a small number (16) of weak relation locks cheaply. If a backend needs
to hold more locks, it has to insert them into the shared lock table.
This is considerably more expensive, and may be subject to contention
(especially on many-core systems).
The limit of 16 fast-path locks was always rather low, because we have
to lock all relations - not just tables, but also indexes, views, etc.
For planning we need to lock all relations that might be used in the
plan, not just those that actually get used in the final plan. So even
with rather simple queries and schemas, we often need significantly more
than 16 locks.
As partitioning gets used more widely, and the number of partitions
increases, this limit is trivial to hit. Complex queries may easily use
hundreds or even thousands of locks. For workloads doing a lot of I/O
this is not noticeable, but for workloads accessing only data in RAM,
the access to the shared lock table may be a serious issue.
This commit removes the hard-coded limit of the number of fast-path
locks. Instead, the size of the fast-path arrays is calculated at
startup, and can be set much higher than the original 16-lock limit.
The overall fast-path locking protocol remains unchanged.
The variable-sized fast-path arrays can no longer be part of PGPROC, but
are allocated as a separate chunk of shared memory and then references
from the PGPROC entries.
The fast-path slots are organized as a 16-way set associative cache. You
can imagine it as a hash table of 16-slot "groups". Each relation is
mapped to exactly one group using hash(relid), and the group is then
processed using linear search, just like the original fast-path cache.
With only 16 entries this is cheap, with good locality.
Treating this as a simple hash table with open addressing would not be
efficient, especially once the hash table gets almost full. The usual
remedy is to grow the table, but we can't do that here easily. The
access would also be more random, with worse locality.
The fast-path arrays are sized using the max_locks_per_transaction GUC.
We try to have enough capacity for the number of locks specified in the
GUC, using the traditional 2^n formula, with an upper limit of 1024 lock
groups (i.e. 16k locks). The default value of max_locks_per_transaction
is 64, which means those instances will have 64 fast-path slots.
The main purpose of the max_locks_per_transaction GUC is to size the
shared lock table. It is often set to the "average" number of locks
needed by backends, with some backends using significantly more locks.
This should not be a major issue, however. Some backens may have to
insert locks into the shared lock table, but there can't be too many of
them, limiting the contention.
The only solution is to increase the GUC, even if the shared lock table
already has sufficient capacity. That is not free, especially in terms
of memory usage (the shared lock table entries are fairly large). It
should only happen on machines with plenty of memory, though.
In the future we may consider a separate GUC for the number of fast-path
slots, but let's try without one first.
Reviewed-by: Robert Haas, Jakub Wartak
Discussion: https://postgr.es/m/510b887e-c0ce-4a0c-a17a-2c6abb8d9a5c@enterprisedb.com
Teach _bt_preprocess_array_keys to eliminate redundant array equality
scan keys directly, rather than just marking them as redundant. Its
_bt_preprocess_keys caller is no longer required to ignore input scan
keys that were marked redundant in this way. Oversights like the one
fixed by commit f22e17f7 are no longer possible.
The new scheme also makes it easier for _bt_preprocess_keys to output a
so.keyData[] scan key array with _more_ scan keys than it was passed in
its scan.keyData[] input scan key array. An upcoming patch that adds
skip scan optimizations to nbtree will take advantage of this.
In passing, remove and rename certain _bt_preprocess_keys variables to
make the difference between our input scan key array and our output scan
key array clearer.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CAH2-Wz=9A_UtM7HzUThSkQ+BcrQsQZuNhWOvQWK06PRkEp=SKQ@mail.gmail.com
table_beginscan_parallel and index_beginscan_parallel contain
Asserts checking that the relation a worker will use in
a parallel scan is the same one the leader intended. However,
they were checking for relation OID match, which was not strong
enough to detect the mismatch problem fixed in 126ec0bc7.
What would be strong enough is to compare relfilenodes instead.
Arguably, that's a saner definition anyway, since a scan surely
operates on a physical relation not a logical one. Hence,
store and compare RelFileLocators not relation OIDs. Also
ensure that index_beginscan_parallel checks the index identity
not just the table identity.
Discussion: https://postgr.es/m/2127254.1726789524@sss.pgh.pa.us
Commit 5bf748b8, which enhanced nbtree ScalarArrayOp execution, made
parallel index scans work with the new design for arrays via explicit
scheduling of primitive index scans. Under this scheme a parallel index
scan with array keys will perform the same number of index descents as
an equivalent serial index scan (barring corner cases where an
individual parallel worker discovers that it can advance the scan's
array keys without anybody needing to perform another descent of the
index to get to the relevant page on the leaf level).
Despite all this, the pgstats accounting wasn't updated; it continued to
increment the total number of index scans for the rel once per _bt_first
call, no matter the details. As a result, the number of (primitive)
index scans could be over-counted during parallel scans.
To fix, delay incrementing the count of index scans until after we've
established that another descent of the index (using either _bt_search
or _bt_endpoint) is required. That way pg_stat_user_tables.idx_scan
always advances in the same way, regardless of whether or not the scan
makes use of parallelism.
Oversight in commit 5bf748b8, which enhanced nbtree ScalarArrayOp
execution.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CAH2-Wz=E7XrkvscBN0U6V81NK3Q-dQOmivvbEsjG-zwEfDdFpg@mail.gmail.com
Discussion: https://postgr.es/m/CAH2-WzkRqvaqR2CTNqTZP0z6FuL4-3ED6eQB0yx38XBNj1v-4Q@mail.gmail.com
Backpatch: 17-, where nbtree SAOP execution was enhanced.
We need to do RestoreRelationMap before loading catalog-derived
state, else the worker may end up with catalog relcache entries
containing stale relfilenode data. Move up RestoreReindexState
too, on the principle that that should also happen before we
do much of any catalog access.
I think ideally these things would happen even before InitPostgres,
but there are various problems standing in the way of that, notably
that the relmapper thinks "active" mappings should be discarded at
transaction end. The implication of this is that InitPostgres and
RestoreLibraryState will see the same catalog state as an independent
backend would see, which is probably fine; at least, it's been like
that all along.
Per report from Justin Pryzby. There is a case to be made that
this should be back-patched. But given the lack of complaints
before 6e086fa2e and the short amount of time remaining before
17.0 wraps, I'll just put it in HEAD for now.
Discussion: https://postgr.es/m/ZuoU_8EbSTE14o1U@pryzbyj2023
This commit moves pg_wal_replay_wait() procedure to be a neighbor of
WAL-related functions in xlogfuncs.c. The implementation of LSN waiting
continues to reside in the same place.
By proposal from Michael Paquier.
Reported-by: Peter Eisentraut
Discussion: https://postgr.es/m/18c0fa64-0475-415e-a1bd-665d922c5201%40eisentraut.org
Partitioned tables and normal tables have been relying on ATT_TABLE in
ATSimplePermissions() to produce error messages that depend on the
relation's relkind, because both relkinds currently support the same set
of ALTER TABLE subcommands.
A patch to restrict SET LOGGED/UNLOGGED for partitioned tables is under
discussion, and introducing ATT_PARTITIONED_TABLE makes subcommand
restrictions for partitioned tables easier to deal with, so let's add
one. There is no functional change.
Author: Michael Paquier
Reviewed-by: Nathan Bossart
Discussion: https://postgr.es/m/Zt6cDnwSvnuLLnak@paquier.xyz
nodeRecursiveunion.c makes use of two tuplestores and, until now, would
delete and recreate one of these tuplestores after every recursive
iteration.
Here we adjust that behavior and instead reuse one of the existing
tuplestores and just empty it of all tuples using tuplestore_clear().
This saves some free/malloc roundtrips and has shown a 25-30% performance
improvement for queries that perform very little work between recursive
iterations.
This also paves the way to add some EXPLAIN ANALYZE telemetry output for
recursive common table expressions, similar to what was done in 1eff8279d
and 95d6e9af0. Previously calling tuplestore_end() would have caused
the maximum storage space used to be lost.
Reviewed-by: Tatsuo Ishii
Discussion: https://postgr.es/m/CAApHDvr9yW0YRiK8A2J7nvyT8g17YzbSfOviEWrghazKZbHbig@mail.gmail.com
This commit adds three sanity checks in code paths of the executor where
it is possible to use hooks, checking that a query ID is reported in
pg_stat_activity if compute_query_id is enabled:
- ExecutorRun()
- ExecutorFinish()
- ExecutorEnd()
This causes the test in pg_stat_statements added in 933848d16d to
complain immediately in ExecutorRun(). The idea behind this commit is
to help extensions to detect if they are missing query ID reports when a
query goes through the executor. Perhaps this will prove to be a bad
idea, but let's see where this experience goes in v18 and newer
versions.
Reviewed-by: Sami Imseih
Discussion: https://postgr.es/m/ZuJb5xCKHH0A9tMN@paquier.xyz
This opens the possibility to define keys for more types of statistics
kinds in PgStat_HashKey, the first case being 8-byte query IDs for
statistics like pg_stat_statements.
This increases the size of PgStat_HashKey from 12 to 16 bytes, while
PgStatShared_HashEntry, entry stored in the dshash for pgstats, keeps
the same size due to alignment.
xl_xact_stats_item, that tracks the stats items to drop in commit WAL
records, is increased from 12 to 16 bytes. Note that individual chunks
in commit WAL records should be multiples of sizeof(int), hence 8-byte
object IDs are stored as two uint32, based on a suggestion from Heikki
Linnakangas.
While on it, the field of PgStat_HashKey is renamed from "objoid" to
"objid", as for some stats kinds this field does not refer to OIDs but
just IDs, like for replication slot stats.
This commit bumps the following format variables:
- PGSTAT_FILE_FORMAT_ID, as PgStat_HashKey is written to the stats file
for non-serialized stats kinds in the dshash table.
- XLOG_PAGE_MAGIC for the changes in xl_xact_stats_item.
- Catalog version, for the SQL function pg_stat_have_stats().
Reviewed-by: Bertrand Drouvot
Discussion: https://postgr.es/m/ZsvTS9EW79Up8I62@paquier.xyz
This commit adds query ID reports for two code paths when processing
extended query protocol messages:
- When receiving a bind message, setting it to the first Query retrieved
from a cached cache.
- When receiving an execute message, setting it to the first PlannedStmt
stored in a portal.
An advantage of this method is that this is able to cover all the types
of portals handled in the extended query protocol, particularly these
two when the report done in ExecutorStart() is not enough (neither is an
addition in ExecutorRun(), actually, for the second point):
- Multiple execute messages, with multiple ExecutorRun().
- Portal with execute/fetch messages, like a query with a RETURNING
clause and a fetch size that stores the tuples in a first execute
message going though ExecutorStart() and ExecuteRun(), followed by one
or more execute messages doing only fetches from the tuplestore created
in the first message. This corresponds to the case where
execute_is_fetch is set, for example.
Note that the query ID reporting done in ExecutorStart() is still
necessary, as an EXECUTE requires it. Query ID reporting is optimistic
and more calls to pgstat_report_query_id() don't matter as the first
report takes priority except if the report is forced. The comment in
ExecutorStart() is adjusted to reflect better the reality with the
extended query protocol.
The test added in pg_stat_statements is a courtesy of Robert Haas. This
uses psql's \bind metacommand, hence this part is backpatched down to
v16.
Reported-by: Kaido Vaikla, Erik Wienhold
Author: Sami Imseih
Reviewed-by: Jian He, Andrei Lepikhov, Michael Paquier
Discussion: https://postgr.es/m/CA+427g8DiW3aZ6pOpVgkPbqK97ouBdf18VLiHFesea2jUk3XoQ@mail.gmail.com
Discussion: https://postgr.es/m/CA+TgmoZxtnf_jZ=VqBSyaU8hfUkkwoJCJ6ufy4LGpXaunKrjrg@mail.gmail.com
Discussion: https://postgr.es/m/1391613709.939460.1684777418070@office.mailbox.org
Backpatch-through: 14
Commits 041b9680 and 6377e12a changed the interface of
scan_analyze_next_block() to take a ReadStream instead of a BlockNumber
and a BufferAccessStrategy, and to return a value to indicate when the
stream has run out of blocks.
This caused integration problems for at least one known extension that
uses specially encoded BlockNumber values that map to different
underlying storage, because acquire_sample_rows() sets up the stream so
that read_stream_next_buffer() reads blocks from the main fork of the
relation's SMgrRelation.
Provide read_stream_next_block(), as a way for such an extension to
access the stream of raw BlockNumbers directly and forward them to its
own ReadBuffer() calls after decoding, as it could in earlier releases.
The new function returns the BlockNumber and BufferAccessStrategy that
were previously passed directly to scan_analyze_next_block().
Alternatively, an extension could wrap the stream of BlockNumbers in
another ReadStream with a callback that performs any decoding required
to arrive at real storage manager BlockNumber values, so that it could
benefit from the I/O combining and concurrency provided by
read_stream.c.
Another class of table access method that does nothing in
scan_analyze_next_block() because it is not block-oriented could use
this function to control the number of block sampling loops. It could
match the previous behavior with "return read_stream_next_block(stream,
&bas) != InvalidBlockNumber".
Ongoing work is expected to provide better ANALYZE support for table
access methods that don't behave like heapam with respect to storage
blocks, but that will be for future releases.
Back-patch to 17.
Reported-by: Mats Kindahl <mats@timescale.com>
Reviewed-by: Mats Kindahl <mats@timescale.com>
Discussion: https://postgr.es/m/CA%2B14425%2BCcm07ocG97Fp%2BFrD9xUXqmBKFvecp0p%2BgV2YYR258Q%40mail.gmail.com
Since we introduced unlogged sequences in v15, identity sequences
have defaulted to having the same persistence as their owning table.
However, it is possible to change that with ALTER SEQUENCE, and
pg_dump tries to preserve the logged-ness of sequences when it doesn't
match (as indeed it wouldn't for an unlogged table from before v15).
The fly in the ointment is that ALTER SEQUENCE SET [UN]LOGGED fails
in binary-upgrade mode, because it needs to assign a new relfilenode
which we cannot permit in that mode. Thus, trying to pg_upgrade a
database containing a mismatching identity sequence failed.
To fix, add syntax to ADD/ALTER COLUMN GENERATED AS IDENTITY to allow
the sequence's persistence to be set correctly at creation, and use
that instead of ALTER SEQUENCE SET [UN]LOGGED in pg_dump. (I tried to
make SET [UN]LOGGED work without any pg_dump modifications, but that
seems too fragile to be a desirable answer. This way should be
markedly faster anyhow.)
In passing, document the previously-undocumented SEQUENCE NAME option
that pg_dump also relies on for identity sequences; I see no value
in trying to pretend it doesn't exist.
Per bug #18618 from Anthony Hsu.
Back-patch to v15 where we invented this stuff.
Discussion: https://postgr.es/m/18618-d4eb26d669ed110a@postgresql.org
* Rename $node_standby1 to $node_standby in 043_wal_replay_wait.pl as there
is only one standby.
* Remove useless debug printing in 043_wal_replay_wait.pl.
* Fix typo in one check description in 043_wal_replay_wait.pl.
* Fix some wording in comments and documentation.
Reported-by: Alexander Lakhin
Discussion: https://postgr.es/m/1d7b08f2-64a2-77fb-c666-c9a74c68eeda%40gmail.com
Reviewed-by: Alexander Lakhin
Commit 5bf748b8, which enhanced nbtree ScalarArrayOp execution, made
parallel index scans work with the new design for arrays via explicit
scheduling of primitive index scans. A backend that successfully
scheduled the scan's next primitive index scan saved its backend local
array keys in shared memory. Any backend could pick up the scheduled
primitive scan within _bt_first. This scheme decouples scheduling a
primitive scan from starting the scan (by performing another descent of
the index via a _bt_search call from _bt_first) to make things robust.
The scheme had a deadlock hazard, at least when the leader process
participated in the scan. _bt_parallel_seize had a code path that made
backends that were not in an immediate position to start a scheduled
primitive index scan wait for some other backend to do so instead.
Under the right circumstances, the leader process could wait here
forever: the leader would wait for any other backend to start the
primitive scan, while every worker was busy waiting on the leader to
consume tuples from the scan's tuple queue.
To fix, don't wait for a scheduled primitive index scan to be started by
some other eligible backend from within _bt_parallel_seize (when the
calling backend isn't in a position to do so itself). Return false
instead, while recording that the scan has a scheduled primitive index
scan in backend local state. This leaves the backend in the same state
as the existing case where a backend schedules (or tries to schedule)
another primitive index scan from within _bt_advance_array_keys, before
calling _bt_parallel_seize. _bt_parallel_seize already handles that
case by returning false without waiting, and without unsetting the
backend local state. Leaving the backend in this state enables it to
start a previously scheduled primitive index scan once it gets back to
_bt_first.
Oversight in commit 5bf748b8, which enhanced nbtree ScalarArrayOp
execution.
Matthias van de Meent, with tweaks by me.
Author: Matthias van de Meent <boekewurm+postgres@gmail.com>
Reported-By: Tomas Vondra <tomas@vondra.me>
Reviewed-By: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-WzmMGaPa32u9x_FvEbPTUkP5e95i=QxR8054nvCRydP-sw@mail.gmail.com
Backpatch: 17-, where nbtree SAOP execution was enhanced.
Add PERIOD clause to foreign key constraint definitions. This is
supported for range and multirange types. Temporal foreign keys check
for range containment instead of equality.
This feature matches the behavior of the SQL standard temporal foreign
keys, but it works on PostgreSQL's native ranges instead of SQL's
"periods", which don't exist in PostgreSQL (yet).
Reference actions ON {UPDATE,DELETE} {CASCADE,SET NULL,SET DEFAULT}
are not supported yet.
(previously committed as 34768ee361, reverted by 8aee330af55; this is
essentially unchanged from those)
Author: Paul A. Jungwirth <pj@illuminatedcomputing.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
Add WITHOUT OVERLAPS clause to PRIMARY KEY and UNIQUE constraints.
These are backed by GiST indexes instead of B-tree indexes, since they
are essentially exclusion constraints with = for the scalar parts of
the key and && for the temporal part.
(previously committed as 46a0cd4cef, reverted by 46a0cd4cefb; the new
part is this:)
Because 'empty' && 'empty' is false, the temporal PK/UQ constraint
allowed duplicates, which is confusing to users and breaks internal
expectations. For instance, when GROUP BY checks functional
dependencies on the PK, it allows selecting other columns from the
table, but in the presence of duplicate keys you could get the value
from any of their rows. So we need to forbid empties.
This all means that at the moment we can only support ranges and
multiranges for temporal PK/UQs, unlike the original patch (above).
Documentation and tests for this are added. But this could
conceivably be extended by introducing some more general support for
the notion of "empty" for other types.
Author: Paul A. Jungwirth <pj@illuminatedcomputing.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
This is support function 12 for the GiST AM and translates
"well-known" RT*StrategyNumber values into whatever strategy number is
used by the opclass (since no particular numbers are actually
required). We will use this to support temporal PRIMARY
KEY/UNIQUE/FOREIGN KEY/FOR PORTION OF functionality.
This commit adds two implementations, one for internal GiST opclasses
(just an identity function) and another for btree_gist opclasses. It
updates btree_gist from 1.7 to 1.8, adding the support function for
all its opclasses.
(previously committed as 6db4598fcb, reverted by 8aee330af55; this is
essentially unchanged from those)
Author: Paul A. Jungwirth <pj@illuminatedcomputing.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
This commit is similar to 1eff8279d and expands the idea to Window
aggregate nodes so that users can know how much memory or disk the
tuplestore used.
This commit uses newly introduced tuplestore_get_stats() to inquire this
information and add some additional output in EXPLAIN ANALYZE to
display the information for the Window aggregate node.
Reviewed-by: David Rowley, Ashutosh Bapat, Maxim Orlov, Jian He
Discussion: https://postgr.es/m/20240706.202254.89740021795421286.ishii%40postgresql.org
In existing releases of libxml2, xmlXPathCompile can be driven
to stack overflow because it fails to protect itself against
too-deeply-nested input. While there is an upstream fix as of
yesterday, it will take years for that to propagate into all
shipping versions. In the meantime, we can protect our own
usages basically for free by calling xmlXPathCtxtCompile instead.
(The actual bug is that libxml2 keeps its nesting counter in the
xmlXPathContext, and its parsing code was willing to just skip
counting nesting levels if it didn't have a context. So if we supply
a context, all is well. It seems odd actually that it works at all
to not supply a context, because this means that XPath parsing does
not have access to XML namespace info. Apparently libxml2 never
checks namespaces until runtime? Anyway, this seems like good
future-proofing even if its only immediate effect is to dodge a bug.)
Sadly, this hack only offers protection with libxml2 2.9.11 and newer.
Before that there are multiple similar problems, so if you are
processing untrusted XML it behooves you to get a newer version.
But we have some pretty old libxml2 in the buildfarm, so it seems
impractical to add a regression test to verify this fix.
Per bug #18617 from Jingzhou Fu. Back-patch to all supported
versions.
Discussion: https://postgr.es/m/18617-1cee4d2ed1f4e7ae@postgresql.org
Discussion: https://gitlab.gnome.org/GNOME/libxml2/-/issues/799
When we are building a hash index that is large enough to need
pre-sorting (larger than either maintenance_work_mem or NBuffers),
the initial sorting phase is interruptible, but the insertion
phase wasn't. Add the missing CHECK_FOR_INTERRUPTS().
Per bug #18616 from Alexander Lakhin. Back-patch to all
supported branches.
Pavel Borisov
Discussion: https://postgr.es/m/18616-acbb9e5caf41e964@postgresql.org
Since e9931bfb75, ctype_is_c is part of pg_locale_t. Some functions
passed a pg_locale_t and a bool argument separately. This can now be
combined into one argument.
Since some callers call MatchText() with locale 0, it is a bit
confusing whether this is all correct. But it is the case that only
callers that pass a non-zero locale object to MatchText() end up
checking locale->ctype_is_c. To make that flow a bit more
understandable, add the locale argument to MATCH_LOWER() and GETCHAR()
in like_match.c, instead of implicitly taking it from the outer scope.
Reviewed-by: Jeff Davis <pgsql@j-davis.com>
Discussion: https://www.postgresql.org/message-id/84d415fc-6780-419e-b16c-61a0ca819e2b@eisentraut.org
Remove redundant checks for locale->collate_is_c now that we always
have a valid pg_locale_t.
Also, remove pg_locale_deterministic() wrapper, which is no longer
useful after commit e9931bfb75. Just check the field directly,
consistent with other fields in pg_locale_t.
Author: Andreas Karlsson
Discussion: https://postgr.es/m/60929555-4709-40a7-b136-bcb44cff5a3c@proxel.se
The operative check is for a deterministic collation, so the check for
DEFAULT_COLLATION is redundant. Furthermore, it will be wrong if we
ever support a non-deterministic default collation.
Author: Andreas Karlsson
Discussion: https://postgr.es/m/60929555-4709-40a7-b136-bcb44cff5a3c@proxel.se
Discussion of commit ed055d249 revealed that we don't actually
want jsonpath's .string() method to depend on DateStyle, nor
TimeZone either, because the non-"_tz" jsonpath functions are
supposed to be immutable. Potentially we could allow a TimeZone
dependency in the "_tz" variants, but it seems better to just
uniformly define this method as returning the same string that
jsonb text output would do. That's easier to implement too,
saving a couple dozen lines.
Patch by me, per complaint from Peter Eisentraut. Back-patch
to v17 where this feature came in (in 66ea94e8e). Also
back-patch ed055d249 to provide test cases.
Discussion: https://postgr.es/m/5e8879d0-a3c8-4be2-950f-d83aa2af953a@eisentraut.org
This function checks whether a user has specific privileges on a large object,
identified by OID. The user can be provided by name, OID,
or default to the current user. If the specified large object doesn't exist,
the function returns NULL. It raises an error for a non-existent user name.
This behavior is basically consistent with other privilege inquiry functions
like has_table_privilege.
Bump catalog version.
Author: Yugo Nagata
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/20240702163444.ab586f6075e502eb84f11b1a@sranhm.sraoss.co.jp
myLargeObjectExists() and LargeObjectExists() had nearly identical code,
except for handling snapshots. This commit renames myLargeObjectExists()
to LargeObjectExistsWithSnapshot() and refactors LargeObjectExists()
to call it internally, reducing duplication.
Author: Yugo Nagata
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/20240702163444.ab586f6075e502eb84f11b1a@sranhm.sraoss.co.jp
hashvalidate(), which validates the signatures of support functions
for the hash AM, contained several hardcoded exceptions. For example,
hash/date_ops support function 1 was hashint4(), which would
ordinarily fail validation because the function argument is int4, not
date. But this works internally because int4 and date are of the same
size. There are several more exceptions like this that happen to work
and were allowed historically but would now fail the function
signature validation.
This patch removes those exceptions by providing new support functions
that have the proper declared signatures. They internally share most
of the code with the "wrong" functions they replace, so the behavior
is still the same.
With the exceptions gone, hashvalidate() is now simplified and relies
fully on check_amproc_signature().
hashvarlena() and hashvarlenaextended() are kept in pg_proc.dat
because some extensions currently use them to build hash functions for
their own types, and we need to keep exposing these functions as
"LANGUAGE internal" functions for that to continue to work.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://www.postgresql.org/message-id/flat/29c3b746-69e7-482a-b37c-dbbf7e5b009b@eisentraut.org
The RULE privilege for tables was removed in v8.2, but for backward
compatibility, GRANT/REVOKE and privilege functions like
has_table_privilege continued to accept the RULE keyword without
any effect.
After discussions on pgsql-hackers, it was agreed that this compatibility
is no longer needed. Since it's been long enough since the deprecation,
we've decided to fully remove support for RULE privilege,
so GRANT/REVOKE and privilege functions will no longer accept it.
Author: Fujii Masao
Reviewed-by: Nathan Bossart
Discussion: https://postgr.es/m/976a3581-6939-457f-b947-fc3dc836c083@oss.nttdata.com
When systable_beginscan() and systable_beginscan_ordered() choose an
index scan, they remap the attribute numbers in the passed-in scan
keys to the attribute numbers of the index, and then write those
remapped attribute numbers back into the scan key passed by the
caller. This second part is surprising and gratuitous. It means that
a scan key cannot safely be used more than once (but it might
sometimes work, depending on circumstances). Also, there is no value
in providing these remapped attribute numbers back to the caller,
since they can't do anything with that.
Fix that by making a copy of the scan keys passed by the caller and
make the modifications there.
Also, some code that had to work around the previous situation is
simplified.
Discussion: https://www.postgresql.org/message-id/flat/f8c739d9-f48d-4187-b214-df3391ba41ab@eisentraut.org
This brings more clarity to heapam.c, by cleanly separating all the
logic related to WAL replay and the rest of Heap and Heap2, similarly
to other RMGRs like hash, btree, etc.
The header reorganization is also nice in heapam.c, cutting half of the
headers required.
Author: Li Yong
Reviewed-by: Sutou Kouhei, Michael Paquier
Discussion: https://postgr.es/m/EFE55E65-D7BD-4C6A-B630-91F43FD0771B@ebay.com
1eff8279d added an API to tuplestore.c to allow callers to obtain
storage telemetry data. That API wasn't quite good enough for callers
that perform tuplestore_clear() as the telemetry functions only
accounted for the current state of the tuplestore, not the maximums
before tuplestore_clear() was called.
There's a pending patch that would like to add tuplestore telemetry
output to EXPLAIN ANALYZE for WindowAgg. That node type uses
tuplestore_clear() before moving to the next window partition and we
want to show the maximum space used, not the space used for the final
partition.
Reviewed-by: Tatsuo Ishii, Ashutosh Bapat
Discussion: https://postgres/m/CAApHDvoY8cibGcicLV0fNh=9JVx9PANcWvhkdjBnDCc9Quqytg@mail.gmail.com
Currently, when WITH CONDITIONAL WRAPPER is specified, array wrappers
are applied even to a single SQL/JSON item if it is a scalar JSON
value, but this behavior does not comply with the standard.
To fix, apply wrappers only when there are multiple SQL/JSON items
in the result.
Reported-by: Peter Eisentraut <peter@eisentraut.org>
Author: Peter Eisentraut <peter@eisentraut.org>
Author: Amit Langote <amitlangote09@gmail.com>
Reviewed-by: Andrew Dunstan <andrew@dunslane.net>
Discussion: https://postgr.es/m/8022e067-818b-45d3-8fab-6e0d94d03626%40eisentraut.org
Backpatch-through: 17
check_agglevels_and_constraints() asserted that if we find an
aggregate function in an EXPR_KIND_FROM_SUBSELECT expression, the
expression must be in a LATERAL subquery. Alexander Lakhin found a
case where that's not so: because of the odd scoping rules for NEW/OLD
within a rule, a reference to NEW/OLD could cause an aggregate to be
considered top-level even though it's in an unmarked sub-select.
The error message that would be thrown seems sufficiently on-point,
so just remove the Assert. (Hence, this is not a bug for production
builds.)
This Assert was added by me in commit eaccfded9 (9.3 era). It looks
like I put it in to cross-check that the new logic for detecting
misplaced aggregates (using agglevelsup) caught the same cases that a
previous check on p_lateral_active did. So there might have been some
related misbehavior before eaccfded9 ... but that's very ancient
history by now, so I didn't dig any deeper.
Per bug #18608 from Alexander Lakhin. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/18608-48de0717508ee429@postgresql.org
The index access methods all had similar code that copied the
passed-in scan keys to local storage. They all used memmove() for
that, which is not wrong, but it seems confusing not to use memcpy()
when that would work. Presumably, this was all once copied from
ancient code and never adjusted.
Discussion: https://www.postgresql.org/message-id/flat/f8c739d9-f48d-4187-b214-df3391ba41ab@eisentraut.org
When building a JSON object, the code builds a hash table of keys, to
allow checking if the keys are unique. The uniqueness check and adding
the new key happens in json_unique_check_key(), but this assumes the
pointer to the key remains valid.
Unfortunately, two places passed pointers to keys in a buffer, while
also appending more data (additional key/value pairs) to the buffer.
With enough data the buffer is resized by enlargeStringInfo(), which
calls repalloc(), invalidating the earlier key pointers.
Due to this the uniqueness check may fail with both false negatives and
false positives, producing JSON objects with duplicate keys or failing
to produce a perfectly valid JSON object.
This affects multiple functions that enforce uniqueness of keys, all
introduced in PG16 with the new SQL/JSON:
- json_object_agg_unique / jsonb_object_agg_unique
- json_object / jsonb_objectagg
Existing regression tests did not detect the issue, simply because the
initial buffer size is 1024 and the objects were small enough not to
require the repalloc.
With a sufficiently large object, AddressSanitizer reported the access
to invalid memory immediately. So would valgrind, of course.
Fixed by copying the key into the hash table memory context, and adding
regression tests with enough data to repalloc the buffer. Backpatch to
16, where the functions were introduced.
Reported by Alexander Lakhin. Investigation and initial fix by Junwang
Zhao, with various improvements and tests by me.
Reported-by: Alexander Lakhin
Author: Junwang Zhao, Tomas Vondra
Backpatch-through: 16
Discussion: https://postgr.es/m/18598-3279ed972a2347c7@postgresql.org
Discussion: https://postgr.es/m/CAEG8a3JjH0ReJF2_O7-8LuEbO69BxPhYeXs95_x7+H9AMWF1gw@mail.gmail.com
The first part of the assertion verifying that the passed index must be PK
or RI was incorrectly passing index relation instead of heap relation in
GetRelationIdentityOrPK(). The assertion was not failing because the
second part of the assertion which needs to be performed only when remote
relation has REPLICA_IDENTITY_FULL set was also incorrect.
The change is not backpatched because the current coding doesn't lead to
any failure.
Reported-by: Dilip Kumar
Author: Amit Kapila
Reviewed-by: Vignesh C
Discussion: https://postgr.es/m/CAFiTN-tmguaT1DXbCC+ZomZg-oZLmU6BPhr0po7akQSG6vNJrg@mail.gmail.com
Commit 8004953b5 added a hash table to avoid O(N^2) cost in choosing
unique relation aliases while deparsing a view or rule. It did
nothing about the similar O(N^2) (maybe worse) costs of choosing
unique column aliases within each RTE. However, that's now
demonstrably a bottleneck when deparsing CHECK constraints for wide
tables, so let's use a similar hash table to handle those.
The extra cost of setting up the hash table will not be repaid unless
the table has many columns. I've set this up so that we use the brute
force method if there are less than 32 columns. The exact cutoff is
not too critical, but this value seems good because it results in both
code paths getting exercised by existing regression-test cases.
Patch by me; thanks to David Rowley for review.
Discussion: https://postgr.es/m/2885468.1722291250@sss.pgh.pa.us
We must drop whitespace while parsing the input, else libxml2
will include "blank" nodes that interfere with the desired
indentation behavior. The end result is that we didn't indent
nodes separated by whitespace.
Also, it seems that libxml2 may add a trailing newline when working
in DOCUMENT mode. This is semantically insignificant, so strip it.
This is in the gray area between being a bug fix and a definition
change. However, the INDENT option is still pretty new (since v16),
so I think we can get away with changing this in stable branches.
Hence, back-patch to v16.
Jim Jones
Discussion: https://postgr.es/m/872865a8-548b-48e1-bfcd-4e38e672c1e4@uni-muenster.de
The only current implementation is for btree where it calls
_bt_getrootheight(). Other index types can now also use this to pass
information to their amcostestimate routine. Previously, btree was
hardcoded and other index types could not hook into the optimizer at
this point.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
When generating window_pathkeys, distinct_pathkeys, or sort_pathkeys,
we failed to realize that the grouping/ordering expressions might be
nullable by grouping sets. As a result, we may incorrectly deem that
the PathKeys are redundant by EquivalenceClass processing and thus
remove them from the pathkeys list. That would lead to wrong results
in some cases.
To fix this issue, we mark the grouping expressions nullable by
grouping sets if that is the case. If the grouping expression is a
Var or PlaceHolderVar or constructed from those, we can just add the
RT index of the RTE_GROUP RTE to the existing nullingrels field(s);
otherwise we have to add a PlaceHolderVar to carry on the nullingrel
bit.
However, we have to manually remove this nullingrel bit from
expressions in various cases where these expressions are logically
below the grouping step, such as when we generate groupClause pathkeys
for grouping sets, or when we generate PathTarget for initial input to
grouping nodes.
Furthermore, in set_upper_references, the targetlist and quals of an
Agg node should have nullingrels that include the effects of the
grouping step, ie they will have nullingrels equal to the input
Vars/PHVs' nullingrels plus the nullingrel bit that references the
grouping RTE. In order to perform exact nullingrels matches, we also
need to manually remove this nullingrel bit.
Bump catversion because this changes the querytree produced by the
parser.
Thanks to Tom Lane for the idea to invent a new kind of RTE.
Per reports from Geoff Winkless, Tobias Wendorff, Richard Guo from
various threads.
Author: Richard Guo
Reviewed-by: Ashutosh Bapat, Sutou Kouhei
Discussion: https://postgr.es/m/CAMbWs4_dp7e7oTwaiZeBX8+P1rXw4ThkZxh1QG81rhu9Z47VsQ@mail.gmail.com
If there are subqueries in the grouping expressions, each of these
subqueries in the targetlist and HAVING clause is expanded into
distinct SubPlan nodes. As a result, only one of these SubPlan nodes
would be converted to reference to the grouping key column output by
the Agg node; others would have to get evaluated afresh. This is not
efficient, and with grouping sets this can cause wrong results issues
in cases where they should go to NULL because they are from the wrong
grouping set. Furthermore, during re-evaluation, these SubPlan nodes
might use nulled column values from grouping sets, which is not
correct.
This issue is not limited to subqueries. For other types of
expressions that are part of grouping items, if they are transformed
into another form during preprocessing, they may fail to match lower
target items. This can also lead to wrong results with grouping sets.
To fix this issue, we introduce a new kind of RTE representing the
output of the grouping step, with columns that are the Vars or
expressions being grouped on. In the parser, we replace the grouping
expressions in the targetlist and HAVING clause with Vars referencing
this new RTE, so that the output of the parser directly expresses the
semantic requirement that the grouping expressions be gotten from the
grouping output rather than computed some other way. In the planner,
we first preprocess all the columns of this new RTE and then replace
any Vars in the targetlist and HAVING clause that reference this new
RTE with the underlying grouping expressions, so that we will have
only one instance of a SubPlan node for each subquery contained in the
grouping expressions.
Bump catversion because this changes the querytree produced by the
parser.
Thanks to Tom Lane for the idea to invent a new kind of RTE.
Per reports from Geoff Winkless, Tobias Wendorff, Richard Guo from
various threads.
Author: Richard Guo
Reviewed-by: Ashutosh Bapat, Sutou Kouhei
Discussion: https://postgr.es/m/CAMbWs4_dp7e7oTwaiZeBX8+P1rXw4ThkZxh1QG81rhu9Z47VsQ@mail.gmail.com
This change makes the code slightly easier to reason about, because
there is actually no need to know if a specific caller of one of these
routines should fail hard on a PANIC, or just let it go through with a
DEBUG2.
The only caller of XLogFileReadAnyTLI() used DEBUG2, and XLogFileRead()
has never used its emode. This can be simplified since 1bb2558046
that has introduced XLogFileReadAnyTLI(), splitting both.
Author: Yugo Nagata
Discussion: https://postgr.es/m/20240906201043.a640f3b44e755d4db2b6943e@sraoss.co.jp
This change adds WAL usage reporting to the output of ANALYZE VERBOSE
and autoanalyze reports. It aligns the analyze output with VACUUM,
providing consistency. Additionally, it aids in troubleshooting cases
where WAL records are generated during analyze operations.
Author: Anthonin Bonnefoy
Reviewed-by: Masahiko Sawada
Discussion: https://postgr.es/m/CAO6_Xqr__kTTCLkftqS0qSCm-J7_xbRG3Ge2rWhucxQJMJhcRA%40mail.gmail.com
SPI_connect/SPI_connect_ext have not returned any value other than
SPI_OK_CONNECT since commit 1833f1a1c in v10; any errors are thrown
via ereport. (The most likely failure is out-of-memory, which has
always been thrown that way, so callers had better be prepared for
such errors.) This makes it somewhat pointless to check these
functions' result, and some callers within our code haven't been
bothering; indeed, the only usage example within spi.sgml doesn't
bother. So it's likely that the omission has propagated into
extensions too.
Hence, let's standardize on not checking, and document the return
value as historical, while not actually changing these functions'
behavior. (The original proposal was to change their return type
to "void", but that would needlessly break extensions that are
conforming to the old practice.) This saves a small amount of
boilerplate code in a lot of places.
Stepan Neretin
Discussion: https://postgr.es/m/CAMaYL5Z9Uk8cD9qGz9QaZ2UBJFOu7jFx5Mwbznz-1tBbPDQZow@mail.gmail.com
As introduced by f9900df5f9, a REINDEX CONCURRENTLY job done for an
index with predicates or expressions would set PROC_IN_SAFE_IC in its
MyProc->statusFlags, causing it to be ignored by other concurrent
operations.
Such concurrent index rebuilds should never be ignored, as a predicate
or an expression could call a user-defined function that accesses a
different table than the table where the index is rebuilt.
A test that uses injection points is added, backpatched down to 17.
Michail has proposed a different test, but I have added something
simpler with more coverage.
Oversight in f9900df5f9.
Author: Michail Nikolaev
Discussion: https://postgr.es/m/CANtu0oj9A3kZVduFTG0vrmGnKB+DCHgEpzOp0qAyOgmks84j0w@mail.gmail.com
Backpatch-through: 14
When the ON ERROR / ON EMPTY behavior is to return NULL, returning
NULL directly from ExecEvalJsonExprPath() suffices. Therefore, there's
no need to create separate steps to check the error/empty flag or
those to evaluate the the constant NULL expression. This speeds up
common cases because the default ON ERROR / ON EMPTY behavior for
JSON_QUERY() and JSON_VALUE() is to return NULL. However, these steps
are necessary if the RETURNING type is a domain, as constraints on the
domain may need to be checked.
Reported-by: Jian He <jian.universality@gmail.com>
Author: Jian He <jian.universality@gmail.com>
Author: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com
Backpatch-through: 17
In label_sort_with_costsize, the cost_sort function is called with the
parameters 'input_disabled_nodes' and 'input_cost' in the wrong order.
This does not cause any plan diffs in the regression tests, because
label_sort_with_costsize is only used to label the Sort node nicely
for EXPLAIN, and cost numbers are not displayed in regression tests.
Oversight in e22253467. Fixed by passing arguments in the right
order.
Per report from Alexander Lakhin running UBSan.
Author: Alexander Lakhin
Discussion: https://postgr.es/m/a9b7231d-68bc-f117-a07c-96688f3e6aef@gmail.com
This commit adds two callbacks in pgstats to have a better control of
the flush timing of pgstat_report_stat(), whose operation depends on the
three PGSTAT_*_INTERVAL variables:
- have_fixed_pending_cb(), to check if a stats kind has any pending
data waiting for a flush. This is used as a fast path if there are no
pending statistics to flush, and this check is done for fixed-numbered
statistics only if there are no variable-numbered statistics to flush.
A flush will need to happen if at least one callback reports any pending
data.
- flush_fixed_cb(), to do the actual flush.
These callbacks are currently used by the SLRU, WAL and IO statistics,
generalizing the concept for all stats kinds (builtin and custom).
The SLRU and IO stats relied each on one global variable to determine
whether a flush should happen; these are now local to pgstat_slru.c and
pgstat_io.c, cleaning up a bit how the pending flush states are tracked
in pgstat.c.
pgstat_flush_io() and pgstat_flush_wal() are still required, but we do
not need to check their return result anymore.
Reviewed-by: Bertrand Drouvot, Kyotaro Horiguchi
Discussion: https://postgr.es/m/ZtaVO0N-aTwiAk3w@paquier.xyz
The following routines are changed to use the syscache entries added for
pg_extension in 490f869d92:
- get_extension_oid()
- get_extension_name()
- get_extension_schema()
A catalog scan is costly and could easily lead to a noticeable
performance impact when called once or more per query, so this is going
to be helpful for developers for extension data lookups.
Author: Andrei Lepikhov
Reviewed-by: Jelte Fennema-Nio
Discussion: https://postgr.es/m/529295b2-6ba9-4dae-acd1-20a9c6fb8f9a@gmail.com
Instead always fetch the locale and look at the ctype_is_c field.
hba.c relies on regexes working for the C locale without needing
catalog access, which worked before due to a special case for
C_COLLATION_OID in lc_ctype_is_c(). Move the special case to
pg_set_regex_collation() now that lc_ctype_is_c() is gone.
Author: Andreas Karlsson
Discussion: https://postgr.es/m/60929555-4709-40a7-b136-bcb44cff5a3c@proxel.se
pg_stat_get_io() applied TimestampTzGetDatum twice to the
stat_reset_timestamp value. On 64-bit builds that's harmless because
TimestampTzGetDatum is a no-op, but on 32-bit builds it results in
displaying garbage in the stats_reset column of the pg_stat_io view.
Bug dates to commit a9c70b46d which introduced pg_stat_io, so
back-patch to v16 where that came in.
Bertrand Drouvot
Discussion: https://postgr.es/m/Ztrd+XcPTz1zorkg@ip-10-97-1-34.eu-west-3.compute.internal
Digging into the history, this was not necessary even when it was
added, but might have been some time before that. In any case, there
is no use for this now.
Use EMPTY ARRAY instead of EMPTY.
This change does not affect the runtime behavior of JSON_TABLE(),
which continues to return an empty relation ON ERROR. It only alters
whether the default ON ERROR behavior is shown in the deparsed output.
Reported-by: Jian He <jian.universality@gmail.com>
Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com
Backpatch-through: 17
The deparsing code in get_json_expr_options() unnecessarily emitted
the default column-specific ON ERROR / EMPTY behavior when the
top-level ON ERROR behavior in JSON_TABLE was set to ERROR. Fix that
by not overriding the column-specific default, determined based on
the column's JsonExprOp in get_json_table_columns(), with
JSON_BEHAVIOR_ERROR when that is the top-level ON ERROR behavior.
Note that this only removes redundancy; the current deparsing output
is not incorrect, just redundant.
Reviewed-by: Jian He <jian.universality@gmail.com>
Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com
Backpatch-through: 17
When the ON ERROR / ON EMPTY behavior is to return NULL, returning
NULL directly from ExecEvalJsonExprPath() suffices. Therefore, there's
no need to create separate steps to check the error/empty flag or
those to evaluate the the constant NULL expression. This speeds up
common cases because the default ON ERROR / ON EMPTY behavior for
JSON_QUERY() and JSON_VALUE() is to return NULL. However, these steps
are necessary if the RETURNING type is a domain, as constraints on the
domain may need to be checked.
Reported-by: Jian He <jian.universality@gmail.com>
Author: Jian He <jian.universality@gmail.com>
Author: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com
Backpatch-through: 17
Use EMPTY ARRAY instead of EMPTY.
This change does not affect the runtime behavior of JSON_TABLE(),
which continues to return an empty relation ON ERROR. It only alters
whether the default ON ERROR behavior is shown in the deparsed output.
Reported-by: Jian He <jian.universality@gmail.com>
Discussion: https://postgr.es/m/CACJufxEo4sUjKCYtda0_qt9tazqqKPmF1cqhW9KBOUeJFqQd2g@mail.gmail.com
Backpatch-through: 17
