In dumputils, we may have successfully parsed the acls when we discover
that we can't parse the reverse ACLs and then return- check and free
aclitems if that happens.
In dumpTableSchema, move ftoptions and srvname under the relkind !=
RELKIND_VIEW branch (since they're only used there) and then check if
they've been allocated and, if so, free them at the end of that block.
Pointed out by Pavel Raiskup, though I didn't use those patches.
Discussion: https://postgr.es/m/2183976.vkCJMhdhmF@nb.usersys.redhat.com
This does not improve the security and reliability of the touched areas,
but it makes the style more consistent.
Author: Michael Paquier
Reviewed-by- Noah Misch
Discussion: https://postgr.es/m/20180309075538.GD9376@paquier.xyz
This allows control of the directory in which the postmaster sockets
are created for the temporary postmasters started by pg_upgrade.
The default location remains the current working directory, which is
typically fine, but if it is deeply nested then its pathname might
be too long to be a socket name.
In passing, clean up some messiness in pg_upgrade's option handling,
particularly the confusing and undocumented way that configuration-only
datadirs were handled. And fix check_required_directory's substantially
under-baked cleanup of directory pathnames.
Daniel Gustafsson, reviewed by Hironobu Suzuki, some code cleanup by me
Discussion: https://postgr.es/m/E72DD5C3-2268-48A5-A907-ED4B34BEC223@yesql.se
TAP tests on msys need to run with the DTK perl, which understands msys
virtualized paths. Postgres, however, does not understand such paths,
so before a path can be used safely with CREATE TABLESPACE, it needs to
be translated into a path on the underlying file system.
Per report from buildfarm member jacana. Suggested fix is from Andrew
Dunstan.
Discussion: https://postgr.es/m/20181130053555.GF2267@paquier.xyz
Three issues are fixed in this patch:
- Base backups forgot to ignore files specific to EXEC_BACKEND, leading
to spurious warnings when checksums are enabled, per analysis from me.
- pg_verify_checksums forgot about files specific to EXEC_BACKEND,
leading to failures of the tool on any such build, particularly Windows.
This error was originally found by newly-introduced TAP tests in various
buildfarm members using EXEC_BACKEND.
- pg_verify_checksums forgot to count for temporary files and temporary
paths, which could be valid relation files, without checksums, per
report from Andres Freund. More tests are added to cover this case.
A new test case which emulates corruption for a file in a different
tablespace is added, coming from from Michael Banck, while I have coded
the main code and refactored the test code.
Author: Michael Banck, Michael Paquier
Reviewed-by: Stephen Frost, David Steele
Discussion: https://postgr.es/m/20181021134206.GA14282@paquier.xyz
This basically reverts commit d55241af70,
leaving around a portion of the regression tests still adapted with
empty relation files, and corrupted cases. This is also proving to be
failing to check properly relation files located in a non-default
tablespace path.
Per discussion with various folks, including Stephen Frost, David
Steele, Andres Freund, Michael Banck and myself.
Reported-by: Michael Banck
Discussion: https://postgr.es/m/20181021134206.GA14282@paquier.xyz
Backpatch-through: 11
CREATE STATISTICS completion was checking manually for the start and end
of the parenthesised list of types. That works, but we now have a better
way to do that as commit 121213d9d taught word_matches() to allow '*' in
the middle of an alternative. But it only applied that to tab completion
for EXPLAIN, ANALYZE and VACUUM. Use it for CREATE STATISTICS too.
Author: Dagfinn Ilmari Mannsåker
Discussion: https://www.postgresql.org/message-id/flat/d8jwooziy1s.fsf%40dalvik.ping.uio.no
The primary purpose of this commit is to ensure pg_upgrade tests yield
comparable dumps pre/post upgrade, which got broken by 12a53c732 /
578b229718, as the order in pg_largeobject_metadata is likely to
differ pre/post upgrade.
It also seems like a generally good idea to make sure such dumps are
comparable, outside of pg_upgrade tests.
LO metadata already was already dumped in an ordered manner as the
metadata is dumped in a well defined order via
sortDumpableObjectsByTypeName() and sortDumpableObjects(). But large
object data is currently not tracked via that mechanism.
As Tom points out it seems possible that at some point dumpBlobs() was
assumed to dump out objects in a well defined order, due to the use of
DISTINCT, which at that time only was done using sorting.
Per complaint from Andrew Dunstan and discussion with him and Tom
Lane.
Author: Andres Freund
Discussion: https://postgr.es/m/2735.1543333649@sss.pgh.pa.us
Unfortunately ac218aa4f6 missed the fact that a reference to
'pg_catalog.regnamespace'::regclass wouldn't work before that type is
known. Fix that, by replacing the regtype usage with a join to
pg_type.
Reported-By: Tom Lane
Author: Andres Freund
Discussion: https://postgr.es/m/8863.1543297423@sss.pgh.pa.us
Backpatch: 9.5-, like ac218aa4f6
When the regrole (0c90f6769) and regnamespace (cb9fa802b) types were
added in 9.5, pg_upgrade's check for reg* types wasn't updated. While
regrole currently is safe, regnamespace is not.
It seems unlikely that anybody uses regnamespace inside catalog tables
across a pg_upgrade, but the tests should be correct nevertheless.
While at it, reorder the types checked in the query to be
alphabetical. Otherwise it's annoying to compare existing and tested
for types.
Author: Andres Freund
Discussion: https://postgr.es/m/037e152a-cb25-3bcb-4f35-bdc9988f8204@2ndQuadrant.com
Backpatch: 9.5-, as regrole/regnamespace
pg_upgrade previously copied pg_largeobject_metadata over from the old
cluster. That doesn't work, because the table has oids before
578b229718. I missed that.
As most pieces of metadata for large objects already were dumped as
DDL (except for comments overwritten by pg_upgrade, due to the copy of
pg_largeobject_metadata) it seems reasonable to just also dump grants
for large objects. If we ever consider this a relevant performance
problem, we'd need to fix the rest of the already emitted DDL
too.
There's still an open discussion about whether we'll want to force a
specific ordering for the dumped objects, as currently
pg_largeobjects_metadata potentially has a different ordering
before/after pg_upgrade, which can make automated testing a bit
harder.
Reported-By: Andrew Dunstan
Author: Andres Freund
Discussion: https://postgr.es/m/91a8a980-41bc-412b-fba2-2ba71a141c2b@2ndQuadrant.com
"\pset format csv", or --csv, selects comma-separated values table format.
This is compliant with RFC 4180, except that we aren't too picky about
whether the record separator is LF or CRLF; also, the user may choose a
field separator other than comma.
This output format is directly compatible with the server's COPY CSV
format, and will also be useful as input to other programs. It's
considerably safer for that purpose than the old recommendation to
use "unaligned" format, since the latter couldn't handle data
containing the field separator character.
Daniel Vérité, reviewed by Fabien Coelho and David Fetter, some
tweaking by me
Discussion: https://postgr.es/m/a8de371e-006f-4f92-ab72-2bbe3ee78f03@manitou-mail.org
Commit eaf746a5b unintentionally made psql's "latex" output format
inaccessible, since not only "latex" but all abbreviations of it
were considered ambiguous against "latex-longtable". Let's go
back to the longstanding behavior that all shortened versions
mean "latex", and you have to write at least "latex-" to get
"latex-longtable". This leaves the only difference from pre-v12
behavior being that "\pset format a" is considered ambiguous.
The fact that the regression tests didn't expose this is pretty bad,
but fixing it is material for a separate commit.
Discussion: https://postgr.es/m/cb7e1caf-3ea6-450d-af28-f524903a030c@manitou-mail.org
recovery.conf settings are now set in postgresql.conf (or other GUC
sources). Currently, all the affected settings are PGC_POSTMASTER;
this could be refined in the future case by case.
Recovery is now initiated by a file recovery.signal. Standby mode is
initiated by a file standby.signal. The standby_mode setting is
gone. If a recovery.conf file is found, an error is issued.
The trigger_file setting has been renamed to promote_trigger_file as
part of the move.
The documentation chapter "Recovery Configuration" has been integrated
into "Server Configuration".
pg_basebackup -R now appends settings to postgresql.auto.conf and
creates a standby.signal file.
Author: Fujii Masao <masao.fujii@gmail.com>
Author: Simon Riggs <simon@2ndquadrant.com>
Author: Abhijit Menon-Sen <ams@2ndquadrant.com>
Author: Sergei Kornilov <sk@zsrv.org>
Discussion: https://www.postgresql.org/message-id/flat/607741529606767@web3g.yandex.ru/
This commit continues the code improvements started by commit
12788ae49e. With this commit, state machine transitions are better
contained in the routine that was called doCustom() and is now called
advanceConnectionState -- the resulting code is easier to reason about,
since there are no state changes occuring in the outer layer.
This change is prompted by future patches to add more features to
pgbench, which will need to effect some more surgery to this code.
Fabien's original had all the machine state changes inside one routine,
but I (Álvaro) thought that a subroutine to handle command execution is
more straightforward to review, so this commit does not match Fabien's
submission closely. If something is broken, it's probably my fault.
Author: Fabien Coelho, Álvaro Herrera
Reviewed-by: Kirk Jamison
Discussion: https://postgr.es/m/alpine.DEB.2.21.1808111104320.1705@lancre
Previously tables declared WITH OIDS, including a significant fraction
of the catalog tables, stored the oid column not as a normal column,
but as part of the tuple header.
This special column was not shown by default, which was somewhat odd,
as it's often (consider e.g. pg_class.oid) one of the more important
parts of a row. Neither pg_dump nor COPY included the contents of the
oid column by default.
The fact that the oid column was not an ordinary column necessitated a
significant amount of special case code to support oid columns. That
already was painful for the existing, but upcoming work aiming to make
table storage pluggable, would have required expanding and duplicating
that "specialness" significantly.
WITH OIDS has been deprecated since 2005 (commit ff02d0a05280e0).
Remove it.
Removing includes:
- CREATE TABLE and ALTER TABLE syntax for declaring the table to be
WITH OIDS has been removed (WITH (oids[ = true]) will error out)
- pg_dump does not support dumping tables declared WITH OIDS and will
issue a warning when dumping one (and ignore the oid column).
- restoring an pg_dump archive with pg_restore will warn when
restoring a table with oid contents (and ignore the oid column)
- COPY will refuse to load binary dump that includes oids.
- pg_upgrade will error out when encountering tables declared WITH
OIDS, they have to be altered to remove the oid column first.
- Functionality to access the oid of the last inserted row (like
plpgsql's RESULT_OID, spi's SPI_lastoid, ...) has been removed.
The syntax for declaring a table WITHOUT OIDS (or WITH (oids = false)
for CREATE TABLE) is still supported. While that requires a bit of
support code, it seems unnecessary to break applications / dumps that
do not use oids, and are explicit about not using them.
The biggest user of WITH OID columns was postgres' catalog. This
commit changes all 'magic' oid columns to be columns that are normally
declared and stored. To reduce unnecessary query breakage all the
newly added columns are still named 'oid', even if a table's column
naming scheme would indicate 'reloid' or such. This obviously
requires adapting a lot code, mostly replacing oid access via
HeapTupleGetOid() with access to the underlying Form_pg_*->oid column.
The bootstrap process now assigns oids for all oid columns in
genbki.pl that do not have an explicit value (starting at the largest
oid previously used), only oids assigned later by oids will be above
FirstBootstrapObjectId. As the oid column now is a normal column the
special bootstrap syntax for oids has been removed.
Oids are not automatically assigned during insertion anymore, all
backend code explicitly assigns oids with GetNewOidWithIndex(). For
the rare case that insertions into the catalog via SQL are called for
the new pg_nextoid() function can be used (which only works on catalog
tables).
The fact that oid columns on system tables are now normal columns
means that they will be included in the set of columns expanded
by * (i.e. SELECT * FROM pg_class will now include the table's oid,
previously it did not). It'd not technically be hard to hide oid
column by default, but that'd mean confusing behavior would either
have to be carried forward forever, or it'd cause breakage down the
line.
While it's not unlikely that further adjustments are needed, the
scope/invasiveness of the patch makes it worthwhile to get merge this
now. It's painful to maintain externally, too complicated to commit
after the code code freeze, and a dependency of a number of other
patches.
Catversion bump, for obvious reasons.
Author: Andres Freund, with contributions by John Naylor
Discussion: https://postgr.es/m/20180930034810.ywp2c7awz7opzcfr@alap3.anarazel.de
Two issues have been spotted and get fixed here:
- When checking for corrupted files, make sure that pg_verify_checksums
complains about the correct file. In order to make the logic more
robust, all files created are immediately removed once checks on them
are done. The error message generated by pg_verify_checksums also now
includes the file name it sees as corrupted.
- Before running corruption-related tests, empty files are generated
which used names mapping with the corrupted files, potentially leading
to conflicts. So use different set of names for both.
Author: Michael Banck
Discussion: https://postgr.es/m/20181119181119.GC23740@nighthawk.caipicrew.dd-dns.de
In \d and \z, instead of conflating partitioned tables and indexes with
plain ones, set the "type" column and table title differently to make
the distinction obvious. A simple ease-of-use improvement.
Author: Pavel Stehule, Michaël Paquier, Álvaro Herrera
Reviewed-by: Amit Langote
Discussion: https://postgr.es/m/CAFj8pRDMWPgijpt_vPj1t702PgLG4Ls2NCf+rEcb+qGPpossmg@mail.gmail.com
When hostaddr is given, the actual IP address that psql is connected to
can be totally unexpected for the given host. The more verbose output
we now generate makes things clearer. Since the "host" and "hostaddr"
parts of the conninfo could come from different sources (say, one of
them is in the service specification or a URI-style conninfo and the
other is not), this is not as silly as it may first appear. This is
also definitely useful if the hostname resolves to multiple addresses.
Author: Fabien Coelho
Reviewed-by: Pavel Stehule, Arthur Zakirov
Discussion: https://postgr.es/m/alpine.DEB.2.21.1810261532380.27686@lancrehttps://postgr.es/m/alpine.DEB.2.21.1808201323020.13832@lancre
This becomes useful when used to retry a transaction after a
serialization error or deadlock abort. (We don't yet have that feature,
but this is preparation for it.)
While at it, use separate random state for thread administratrivia such
as deciding which script to run, how long to delay for throttling, or
whether to log a message when sampling; this not only makes these tasks
independent of each other, but makes the actual thread run
deterministic.
Author: Marina Polyakova
Reviewed-by: Fabien Coelho
Discussion: https://postgr.es/m/72a0d590d6ba06f242d75c2e641820ec@postgrespro.ru
The previous behavior of preferring the oldest match had the advantage
of not breaking existing scripts when we add a conflicting format name;
but that behavior was undocumented and fragile (it seems just luck that
commit add9182e5 didn't break it). Let's go over to the less mistake-
prone approach of complaining when there are multiple matches.
Since this is a small compatibility break, no back-patch.
Daniel Vérité
Discussion: https://postgr.es/m/cb7e1caf-3ea6-450d-af28-f524903a030c@manitou-mail.org
A table with OIDs that was the first in the dump output would not get
dumped with OIDs enabled. Fix that.
The reason was that the currWithOids flag was declared to be bool but
actually also takes a -1 value for "don't know yet". But under
stdbool.h semantics, that is coerced to true, so the required SET
default_with_oids command is not output again. Change the variable
type to char to fix that.
Reported-by: Derek Nelson <derek@pipelinedb.com>
Add another transfer mode --clone to pg_upgrade (besides the existing
--link and the default copy), using special file cloning calls. This
makes the file transfer faster and more space efficient, achieving
speed similar to --link mode without the associated drawbacks.
On Linux, file cloning is supported on Btrfs and XFS (if formatted with
reflink support). On macOS, file cloning is supported on APFS.
Reviewed-by: Michael Paquier <michael@paquier.xyz>
The installcheck run takes a sizable fraction of test.sh to run. Using
a parallel schedule reduces that noticably.
It's possible that we want to backpatch this at some point, to reduce
buildfarm times, but for now lets just see if this upsets the
buildfarm.
Author: Andres Freund
Discussion: https://postgr.es/m/20181105210039.hh4vvi4vwoq5ba2q@alap3.anarazel.de
This moves one check for conflicting options from the archive restore
code to the main function where other similar checks are performed.
Also reword the error message to be consistent with other messages.
The only option combination impacted is --create specified with
--single-transaction, and informing the caller at an early step saves
from opening the archive worked on. A TAP test is added for this
combination.
Author: Daniel Gustafsson
Reviewed-by: Fabien Coelho
Discussion: https://postgr.es/m/616808BD-4B59-4E6C-97A9-7317F62D5570@yesql.se
This adds tab completion of the clauses WHEN and EXECUTE
FUNCTION|PROCEDURE clauses to CREATE EVENT TRIGGER, similar to CREATE
TRIGGER in the previous commit. This has version-dependent logic so as
FUNCTION is chosen over PROCEDURE for 11 and newer versions.
Author: Dagfinn Ilmari Mannsåker
Reviewed-by: Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/d8jmur4q4yc.fsf@dalvik.ping.uio.no
The change to accept EXECUTE FUNCTION as well as EXECUTE PROCEDURE in
CREATE TRIGGER (added by 0a63f99) forgot to tell psql's tab completion
system about this. In passing, add tab completion of EXECUTE
FUNCTION/PROCEDURE after a complete WHEN ( … ) clause.
This change is version-aware, with FUNCTION being selected automatically
instead of PROCEDURE depending on the backend version, PROCEDURE being
an historical grammar kept for compatibility and considered as
deprecated in v11.
Author: Dagfinn Ilmari Mannsåker
Reviewed-by: Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/d8jmur4q4yc.fsf@dalvik.ping.uio.no
The pg_verify_checksums test tries to create files with corrupt data
named "123." and "123_." But on Windows a file name with a trailing dot
is the same as a file without the trailing dot. In the first case this
will create a file with a "valid" name, which causes the test to fail in
an unexpected way, and in the secongd case this will be redandant as the
test already creates a file named "123_".
Bug discovered by buildfarm animal bowerbird.
PQnotifies() is defined to just process already-read data, not try to read
any more from the socket. (This is a debatable decision, perhaps, but I'm
hesitant to change longstanding library behavior.) The documentation has
long recommended calling PQconsumeInput() before PQnotifies() to ensure
that any already-arrived message would get absorbed and processed.
However, psql did not get that memo, which explains why it's not very
reliable about reporting notifications promptly.
Also, most (not quite all) callers called PQconsumeInput() just once before
a PQnotifies() loop. Taking this recommendation seriously implies that we
should do PQconsumeInput() before each call. This is more important now
that we have "payload" strings in notification messages than it was before;
that increases the probability of having more than one packet's worth
of notify messages. Hence, adjust code as well as documentation examples
to do it like that.
Back-patch to 9.5 to match related server fixes. In principle we could
probably go back further with these changes, but given lack of field
complaints I doubt it's worthwhile.
Discussion: https://postgr.es/m/CAOYf6ec-TmRYjKBXLLaGaB-jrd=mjG1Hzn1a1wufUAR39PQYhw@mail.gmail.com
The original implementation of pg_verify_checksums used a blacklist to
decide which files should be skipped for scanning as they do not include
data checksums, like pg_internal.init or pg_control. However, this
missed two things:
- Some files are created within builds of EXEC_BACKEND and these were
not listed, causing failures on Windows.
- Extensions may create custom files in data folders, causing the tool
to equally fail.
This commit switches to a whitelist-like method instead by checking if
the files to scan are authorized relation files. This is close to a
reverse-engineering of what is defined in relpath.c in charge of
building the relation paths, and we could consider refactoring what this
patch does so as all routines are in a single place. This is left for
later.
This is based on a suggestion from Andres Freund. TAP tests are updated
so as multiple file patterns are tested. The bug has been spotted by
various buildfarm members as a result of b34e84f which has introduced
the TAP tests of pg_verify_checksums.
Author: Michael Paquier
Reviewed-by: Andrew Dunstan, Michael Banck
Discussion: https://postgr.es/m/20181012005614.GC26424@paquier.xyz
Backpatch-through: 11
When an error occurs during a benchmark run, exit with a nonzero exit
code and write a message at the end. Previously, it would just print
the error message when it happened but then proceed to print the run
summary normally and exit with status 0. To still allow
distinguishing setup from run-time errors, we use exit status 2 for
the new state, whereas existing errors during pgbench initialization
use exit status 1.
Reviewed-by: Fabien COELHO <coelho@cri.ensmp.fr>
All options available in the utility get coverage:
- Tests with disabled page checksums.
- Tests with enabled test checksums.
- Emulation of corruption and broken checksums with a full scan and
single relfilenode scan.
This patch has been contributed mainly by Michael Banck and Magnus
Hagander with things presented on various threads, and I have gathered
all the contents into a single patch.
Author: Michael Banck, Magnus Hagander, Michael Paquier
Reviewed-by: Peter Eisentraut
Discussion: https://postgr.es/m/20181005012645.GE1629@paquier.xyz
Historically we forbade datatype-specific comparison functions from
returning INT_MIN, so that it would be safe to invert the sort order
just by negating the comparison result. However, this was never
really safe for comparison functions that directly return the result
of memcmp(), strcmp(), etc, as POSIX doesn't place any such restriction
on those library functions. Buildfarm results show that at least on
recent Linux on s390x, memcmp() actually does return INT_MIN sometimes,
causing sort failures.
The agreed-on answer is to remove this restriction and fix relevant
call sites to not make such an assumption; code such as "res = -res"
should be replaced by "INVERT_COMPARE_RESULT(res)". The same is needed
in a few places that just directly negated the result of memcmp or
strcmp.
To help find places having this problem, I've also added a compile option
to nbtcompare.c that causes some of the commonly used comparators to
return INT_MIN/INT_MAX instead of their usual -1/+1. It'd likely be
a good idea to have at least one buildfarm member running with
"-DSTRESS_SORT_INT_MIN". That's far from a complete test of course,
but it should help to prevent fresh introductions of such bugs.
This is a longstanding portability hazard, so back-patch to all supported
branches.
Discussion: https://postgr.es/m/20180928185215.ffoq2xrq5d3pafna@alap3.anarazel.de
I started out with the idea that we needed to detect use of %m format specs
in contexts other than elog/ereport calls, because we couldn't rely on that
working in *printf calls. But a better answer is to fix things so that it
does work. Now that we're using snprintf.c all the time, we can implement
%m in that and we've fixed the problem.
This requires also adjusting our various printf-wrapping functions so that
they ensure "errno" is preserved when they call snprintf.c.
Remove elog.c's handmade implementation of %m, and let it rely on
snprintf to support the feature. That should provide some performance
gain, though I've not attempted to measure it.
There are a lot of places where we could now simplify 'printf("%s",
strerror(errno))' into 'printf("%m")', but I'm not in any big hurry
to make that happen.
Patch by me, reviewed by Michael Paquier
Discussion: https://postgr.es/m/2975.1526862605@sss.pgh.pa.us
It's fairly silly to truncate the throttle_delay to integer when the only
math we ever do with it requires converting back to double. Furthermore,
given that people are starting to complain about restrictions like only
supporting 1K client connections, I don't think we're very far away from
situations where the precision loss matters. As the code stood, for
example, there's no difference between --rate 100001 and --rate 111111;
both get converted to throttle_delay = 9. Somebody trying to run 100
threads and have each one dispatch around 1K TPS would find this lack of
precision rather surprising, especially since the required per-thread
delays are around 1ms, well within the timing precision of modern systems.
96e1cb4 has added support for --no-publications in pg_dump, pg_dumpall
and pg_restore, but forgot the fact that publication tables also need to
be ignored when this option is used.
Author: Gilles Darold
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/3f48e812-b0fa-388e-2043-9a176bdee27e@dalibo.com
Backpatch-through: 10, where publications have been added.
We haven't touched these since text search functionality landed in core
in 2007 :-(. While the upstream project isn't a beehive of activity,
they do make additions and bug fixes from time to time. Update our
copies of these files.
Also update our documentation about how to keep things in sync, since
they're not making distribution tarballs these days. Fortunately,
their source code turns out to be a breeze to build.
Notable changes:
* The non-UTF8 version of the hungarian stemmer now works in LATIN2
not LATIN1.
* New stemmers have appeared for arabic, indonesian, irish, lithuanian,
nepali, and tamil. These all work in UTF8, and the indonesian and
irish ones also work in LATIN1.
(There are some new stemmers that I did not incorporate, mainly because
their names don't match the underlying languages, suggesting that they're
not to be considered mainstream.)
Worth noting: the upstream Nepali dictionary was contributed by
Arthur Zakirov.
initdb forced because the contents of snowball_create.sql have
changed.
Still TODO: see about updating the stopword lists.
Arthur Zakirov, minor mods and doc work by me
Discussion: https://postgr.es/m/20180626122025.GA12647@zakirov.localdomain
Discussion: https://postgr.es/m/20180219140849.GA9050@zakirov.localdomain
Previously, pgbench always used select(2) for this purpose, but that's
problematic for very high client counts, because select() can't deal
with file descriptor numbers larger than FD_SETSIZE. It's pretty common
for that to be only 1024 or so, whereas modern OSes can allow many more
open files than that. Using poll(2) would surmount that problem, but it
creates another one: poll()'s timeout resolution is only 1ms, which is
poor enough to cause problems with --rate specifications approaching or
exceeding 1K TPS.
On platforms that have ppoll(2), which includes Linux and recent
FreeBSD, we can use that to avoid the FD_SETSIZE problem without any
loss of timeout resolution. Hence, add configure logic to test for
ppoll(), and use it if available.
This patch introduces an abstraction layer into pgbench that could
be extended to support other kernel event-wait APIs such as kevents.
But actually adding such support is a matter for some future patch.
Doug Rady, reviewed by Robert Haas and Fabien Coelho, and whacked around
a good bit more by me
Discussion: https://postgr.es/m/23D017C9-81B7-484D-8490-FD94DEC4DF59@amazon.com
This removes a difference between the standard IsUnderPostmaster
execution environment and that of --boot and --single. In a stand-alone
backend, "SELECT random()" always started at the same seed.
On a system capable of using posix shared memory, initdb could still
conclude "selecting dynamic shared memory implementation ... sysv".
Crashed --boot or --single postgres processes orphaned shared memory
objects having names that collided with the not-actually-random names
that initdb probed. The sysv fallback appeared after ten crashes of
--boot or --single postgres. Since --boot and --single are rare in
production use, systems used for PostgreSQL development are the
principal candidate to notice this symptom.
Back-patch to 9.3 (all supported versions). PostgreSQL 9.4 introduced
dynamic shared memory, but 9.3 does share the "SELECT random()" problem.
Reviewed by Tom Lane and Kyotaro HORIGUCHI.
Discussion: https://postgr.es/m/20180915221546.GA3159382@rfd.leadboat.com