s/const//g wasn't exactly what I was suggesting here ... parameter
declarations of the form "const structtype *param" are good and useful,
so put those occurrences back. Likewise, avoid casting away the const
in a "const void *" parameter.
backend/Makefile was treating errcodes.h as a header always generated
during build, but actually it's a header provided in tarballs. Hence,
must use the absolute-symlink recipe, not the relative-symlink one.
Per bug #6072 from Hartmut Raschick.
As Tom Lane pointed out, "const Relation foo" doesn't guarantee that you
can't modify the data the "foo" pointer points to. It just means that you
can't change the pointer to point to something else within the function,
which is not very useful.
already been marked as PREPARED cannot be killed. Kill the current
transaction instead.
One of the prepared_xacts regression tests actually hits this bug. I
removed the anomaly from the duplicate-gids test so that it fails in the
intended way, and added a new test to check serialization failures with
a prepared transaction.
Dan Ports
MARKED_FOR_DEATH flags into one. We still need the ROLLED_BACK flag to
mark transactions that are in the process of being rolled back. To be
precise, ROLLED_BACK now means that a transaction has already been
discounted from the count of transactions with the oldest xmin, but not
yet removed from the list of active transactions.
Dan Ports
When recursing after an optimization in pull_up_sublinks_qual_recurse, the
available_rels value passed down must include only the relations that are
in the righthand side of the new SEMI or ANTI join; it's incorrect to pull
up a sub-select that refers to other relations, as seen in the added test
case. Per report from BangarRaju Vadapalli.
While at it, rethink the idea of recursing below a NOT EXISTS. That is
essentially the same situation as pulling up ANY/EXISTS sub-selects that
are in the ON clause of an outer join, and it has the same disadvantage:
we'd force the two joins to be evaluated according to the syntactic nesting
order, because the lower join will most likely not be able to commute with
the ANTI join. That could result in having to form a rather large join
product, whereas the handling of a correlated subselect is not quite that
dumb. So until we can handle those cases better, #ifdef NOT_USED that
case. (I think it's okay to pull up in the EXISTS/ANY cases, because SEMI
joins aren't so inflexible about ordering.)
Back-patch to 8.4, same as for previous patch in this area. Fortunately
that patch hadn't made it into any shipped releases yet.
I mis-simplified the test where ANALYZE decided if it could get away
without doing anything: under the new regime, that's never allowed. Per
bug #6068 from Jeff Janes. Back-patch to 8.4, just like previous patch.
For some reason, when we (I) added table lock acquisition to pg_dump,
we didn't think about making it happen as soon as possible after the
start of the transaction. What with subsequent additions, there was
actually quite a lot going on before we got around to that; which sort
of defeats the purpose. Rearrange the order of calls in dumpSchema()
to close the risk window as much as we easily can. Back-patch to all
supported branches.
The previous code went into an infinite loop after overflow. In fact,
an overflow is not really an error; it just means that the current
value is the last one we need to return. So, just arrange to stop
immediately when overflow is detected.
Back-patch all the way.
The code that created the init fork neglected to make sure that the
relation was open at the smgr level before attempting to invoke smgr.
This didn't happen every time; only when the relcache entry was rebuilt
along the way.
Per report from Garick Hamlin.
SSI is based on, as well as the optimizations about relative commit times
and read-only transactions. Plus a bunch of other misc fixes and
improvements.
Dan Ports
Btree pages were recycled after VACUUM deletes all records on a
page and then a subsequent VACUUM occurs after the RecentXmin
horizon is reached. Using RecentXmin meant that we did not respond
correctly to the user controls provide to avoid Hot Standby
conflicts and so spurious conflicts could be generated in some
workload combinations. We now reuse pages only when we reach
RecentGlobalXmin, which can be much later in the presence of long
running queries and is also controlled by vacuum_defer_cleanup_age
and hot_standby_feedback.
Noah Misch and Simon Riggs
Per recommendation from Peter. Neither choice is bulletproof, but this
is the existing style and it does help prevent unexpected environment
variable substitution.
The initial commit of the ALTER TABLE ADD FOREIGN KEY NOT VALID feature
failed to support labeling such constraints as deferrable. The best fix
for this seems to be to fold NOT VALID into ConstraintAttributeSpec.
That's a bit more general than the documented syntax, but it allows
better-targeted syntax error messages.
In addition, do some mostly-but-not-entirely-cosmetic code review for
the whole NOT VALID patch.
This oversight could result in a tuplestore using much more than the
intended amount of memory. It would only happen in a code path that loaded
a tuplestore via tuplestore_putvalues(), and many of those won't emit huge
amounts of data; but cases such as holdable cursors and plpgsql's RETURN
NEXT command could have the problem. The fix ensures that the tuplestore
will switch to write-to-disk mode when it overruns work_mem.
The potential overrun was finite, because we would still count the space
used by the tuple pointer array, so the tuplestore code would eventually
flip into write-to-disk mode anyway. When storing wide tuples we would
go far past the expected work_mem usage before that happened; but this
may account for the lack of prior reports.
Back-patch to 8.4, where tuplestore_putvalues was introduced.
Per bug #6061 from Yann Delorme.
The short-form -z switch didn't work, for lack of telling getopt_long
about it; and even if specified long-form, it failed to do anything,
because the various tests elsewhere in the file would take
Z_DEFAULT_COMPRESSION (which is -1) as meaning "don't compress".
Per bug #6060 from Shigehiro Honda, though I editorialized on his patch
a bit.
the marked-for-death flag. It was only set for a fleeting moment while a
transaction was being cleaned up at rollback. All the places that checked
for the rolled-back flag should also check the marked-for-death flag, as
both flags mean that the transaction will roll back. I also renamed the
marked-for-death into "doomed", which is a lot shorter name.
snapshots, like in REINDEX, are basically non-transactional operations. The
DDL operation itself might participate in SSI, but there's separate
functions for that.
Kevin Grittner and Dan Ports, with some changes by me.
Apparently there is no buildfarm critter exercising this case after all,
because it fails in several places. With this patch, build, install,
check-world, and installcheck-world pass for me on OS X.
is added to the end, and existing resource managers keep their old ids.
We're not going to guarantee on-disk compatibility for 2PC state files over
major releases, but it seems better to avoid changing the ids them anyway.
It will help anyone who might want to write external tools to inspect the
state files to work with files from different versions, if nothing else.
Per complaint from Tom Lane.
ReadRecord's habit of using both direct references to tmpRecPtr and
references to *RecPtr (which is pointing at tmpRecPtr) triggers an
optimization bug in gcc 4.6.0, which apparently has forgotten about
aliasing rules. Avoid the compiler bug, and make the code more readable
to boot, by getting rid of the direct references. Improve the comments
while at it.
Back-patch to all supported versions, in case they get built with 4.6.0.
Tom Lane, with some cosmetic suggestions from Alex Hunsaker
Even if a flag is modified only by the backend owning the transaction, it's
not safe to modify it without a lock. Another backend might be setting or
clearing a different flag in the flags field concurrently, and that
operation might be lost because setting or clearing a bit in a word is not
atomic.
Make did-write flag a simple backend-private boolean variable, because it
was only set or tested in the owning backend (except when committing a
prepared transaction, but it's not worthwhile to optimize for the case of a
read-only prepared transaction). This also eliminates the need to add
locking where that flag is set.
Also, set the did-write flag when doing DDL operations like DROP TABLE or
TRUNCATE -- that was missed earlier.
"Blind writes" are a mechanism to push buffers down to disk when
evicting them; since they may belong to different databases than the one
a backend is connected to, the backend does not necessarily have a
relation to link them to, and thus no way to blow them away. We were
keeping those files open indefinitely, which would cause a problem if
the underlying table was deleted, because the operating system would not
be able to reclaim the disk space used by those files.
To fix, have bufmgr mark such files as transient to smgr; the lower
layer is allowed to close the file descriptor when the current
transaction ends. We must be careful to have any other access of the
file to remove the transient markings, to prevent unnecessary expensive
system calls when evicting buffers belonging to our own database (which
files we're likely to require again soon.)
This commit fixes a bug in the previous one, which neglected to cleanly
handle the LRU ring that fd.c uses to manage open files, and caused an
unacceptable failure just before beta2 and was thus reverted.
"Blind writes" are a mechanism to push buffers down to disk when
evicting them; since they may belong to different databases than the one
a backend is connected to, the backend does not necessarily have a
relation to link them to, and thus no way to blow them away. We were
keeping those files open indefinitely, which would cause a problem if
the underlying table was deleted, because the operating system would not
be able to reclaim the disk space used by those files.
To fix, have bufmgr mark such files as transient to smgr; the lower
layer is allowed to close the file descriptor when the current
transaction ends. We must be careful to have any other access of the
file to remove the transient markings, to prevent unnecessary expensive
system calls when evicting buffers belonging to our own database (which
files we're likely to require again soon.)
SimpleLruTruncate() a page number that's "in the future", because it will
issue a warning and refuse to truncate anything. Instead, we leave behind
the latest segment. If the slru is not needed before XID wrap-around, the
segment will appear as new again, and not be cleaned up until it gets old
enough again. That's a bit unpleasant, but better than not cleaning up
anything.
Also, fix broken calculation to check and warn if the span of the OldSerXid
SLRU is getting too large to fit in the 64k SLRU pages that we have
available. It was not XID wraparound aware.
Kevin Grittner and me.
