Dan Wood diagnosed a long-standing problem that pages containing tuples
that are locked by multixacts containing live lockers may spuriously end
up as candidates for getting their all-visible flag set. This has the
long-term effect that multixacts remain unfrozen; this may previously
pass undetected, but since commit XYZ it would be reported as
"ERROR: found multixact 134100944 from before relminmxid 192042633"
because when a later vacuum tries to freeze the page it detects that a
multixact that should have gotten frozen, wasn't.
Dan proposed a (correct) patch that simply sets a variable to its
correct value, after a bogus initialization. But, per discussion, it
seems better coding to avoid the bogus initializations altogether, since
they could give rise to more bugs later. Therefore this fix rewrites
the logic a little bit to avoid depending on the bogus initializations.
This bug was part of a family introduced in 9.6 by commit a892234f830e;
later, commit 38e9f90a22 fixed most of them, but this one was
unnoticed.
Authors: Dan Wood, Pavan Deolasee, Álvaro Herrera
Reviewed-by: Masahiko Sawada, Pavan Deolasee, Álvaro Herrera
Discussion: https://postgr.es/m/84EBAC55-F06D-4FBE-A3F3-8BDA093CE3E3@amazon.com
This should have been done some years ago as promised in commit
c4dcdd0c2. However, better late than never.
Along the way do a little housekeeping, including using a simpler test
for the python version being tested, and removing a redundant subroutine
parameter. These changes only apply back to release 9.5.
Backpatch to all live releases.
Msys2's uname -s outputs a string beginning MSYS rather than MINGW as is
output by Msys. Allow either in pg_upgrade's test.sh.
Backpatch to all live branches.
The non-cosmetic changes involve teaching the "zic" tzdata compiler about
negative DST. While I'm not currently intending that we start using
negative-DST data right away, it seems possible that somebody would try
to use our copy of zic with bleeding-edge IANA data. So we'd better be
out in front of this change code-wise, even though it doesn't matter for
the data file we're shipping.
Discussion: https://postgr.es/m/30996.1525445902@sss.pgh.pa.us
For querying pg_database about information about the database being
dumped, look up by using current_database() instead of the value
obtained from PQdb(). When using a connection proxy, the value from
PQdb() might not be the real name of the database.
nbtsort.c does not need to truncate away non-key attributes for the
minimum key of the leftmost page on a level, since this is only used to
build a minus infinity downlink for the level's leftmost page.
Truncating away non-key attributes in advance of truncating away all
attributes in _bt_sortaddtup() does not affect the correctness of CREATE
INDEX, but it is misleading.
Author: Peter Geoghegan
Discussion: https://www.postgresql.org/message-id/CAH2-WzkAS2M3ussHG-s_Av=Zo6dPjOxyu5fNRkYnxQV+YzGQ4w@mail.gmail.com
The principle behind the locking was not very well thought-out, and not
documented. Add a section in the README to explain how it's supposed to
work, and change the code so that it actually works that way.
This fixes two bugs:
1. If fast update was turned on concurrently, subsequent inserts to the
pending list would not conflict with predicate locks that were acquired
earlier, on entry pages. The included 'predicate-gin-fastupdate' test
demonstrates that. To fix, make all scans acquire a predicate lock on
the metapage. That lock represents a scan of the pending list, whether
or not there is a pending list at the moment. Forget about the
optimization to skip locking/checking for locks, when fastupdate=off.
2. If a scan finds no match, it still needs to lock the entry page. The
point of predicate locks is to lock the gabs between values, whether
or not there is a match. The included 'predicate-gin-nomatch' test
tests that case.
In addition to those two bug fixes, this removes some unnecessary locking,
following the principle laid out in the README. Because all items in
a posting tree have the same key value, a lock on the posting tree root is
enough to cover all the items. (With a very large posting tree, it would
possibly be better to lock the posting tree leaf pages instead, so that a
"skip scan" with a query like "A & B", you could avoid unnecessary conflict
if a new tuple is inserted with A but !B. But let's keep this simple.)
Also, some spelling fixes.
Author: Heikki Linnakangas with some editorization by me
Review: Andrey Borodin, Alexander Korotkov
Discussion: https://www.postgresql.org/message-id/0b3ad2c2-2692-62a9-3a04-5724f2af9114@iki.fi
We need to use a stamp file to record the runs of these scripts, as
is done on the Unix side. I think I got it right, but can't test.
While at it, extend this handmade dependency logic to also check the
generating script files, as the makefiles do.
Discussion: https://postgr.es/m/16925.1525376229@sss.pgh.pa.us
If a particular output file already exists with the contents it should
have, leave it alone, so that its mod timestamp is not advanced.
In builds using --enable-depend, this can avoid the need to recompile .c
files whose included files didn't actually change. It's not clear whether
it saves much of anything for users of ccache; but the cost of doing the
file comparisons seems to be negligible, so we might as well do it.
For developers using the MSVC toolchain, this will create a regression:
msvc/Solution.pm will sometimes run genbki.pl or Gen_fmgrtab.pl
unnecessarily. I'll look into fixing that separately.
Discussion: https://postgr.es/m/16925.1525376229@sss.pgh.pa.us
Make these rules look more like the ones associated with genbki.pl,
to wit:
* Use a stamp file to record when we last ran the script, instead of
relying on the timestamps of the individual output files.
* Take the knowledge out of backend/Makefile and put it in utils/Makefile
where it belongs. I moved down the handling of errcodes.h and probes.h
too, although those continue to be built by separate processes.
In itself, this is just much-needed cleanup with little practical effect.
However, by decoupling these makefile rules from the timestamps of the
generated header files, we open the door to not advancing those timestamps
unnecessarily, which will be taken advantage of by the next commit.
msvc/Solution.pm should be taught to do things similarly, but I'll leave
that for another commit.
Discussion: https://postgr.es/m/16925.1525376229@sss.pgh.pa.us
Python 3.7 removes the trailing comma in the repr() of
BaseException (see <https://bugs.python.org/issue30399>), leading to
test output differences. Work around that by composing the equivalent
test output in a more manual way.
If an interrupt arrives in the middle of FinishPreparedTransaction
and any callback decide to call CHECK_FOR_INTERRUPTS (e.g.
RemoveTwoPhaseFile can write a warning with ereport, which checks for
interrupts) then it's possible to leave current GXact undeleted.
Backpatch to all supported branches
Stas Kelvich
Discussion: ihttps://www.postgresql.org/message-id/3AD85097-A3F3-4EBA-99BD-C38EDF8D2949@postgrespro.ru
Unify indnkeys/indnatts/indnkeyatts usage for all version of query to get
index information, remove indnkeys column from query as unused.
Author: Marina Polyakova
Noticed by: Peter Eisentraut
Andrew Gierth pointed out that commit 1c72ec6f4 would yield the wrong
answer on big-endian ARM systems, because the data being CRC'd would be
different. To fix that, and avoid the rather unsightly hard-wired
constant, simply compare the hardware and software implementations'
results.
While we're at it, also log the resulting decision at DEBUG1, and error
out if the hw and sw results unexpectedly differ. Also, since this
file must compile for both frontend and backend, avoid incorrect
dependencies on backend-only headers.
In passing, add a comment to postmaster.c about when the CRC function
pointer will get initialized.
Thomas Munro, based on complaints from Andrew Gierth and Tom Lane
Discussion: https://postgr.es/m/HE1PR0801MB1323D171938EABC04FFE7FA9E3110@HE1PR0801MB1323.eurprd08.prod.outlook.com
Since the SPI stack has been moved from TopTransactionContext to
TopMemoryContext, setting _SPI_stack to NULL in AtEOXact_SPI() leaks
memory. In fact, we don't need to do that anymore: We just leave the
allocated stack around for the next SPI use.
Also, refactor the SPI cleanup so that it is run both at transaction end
and when returning to the main loop on an exception. The latter is
necessary when a procedure calls a COMMIT or ROLLBACK command that
itself causes an error.
Failure to use DatumGetFoo/FooGetDatum macros correctly, or at all,
causes some warnings about sign conversion. This is just cosmetic
at the moment but in principle it's a type violation, so clean up
the instances I could find.
autoprewarm.c and sharedfileset.c contained code that unportably
assumed that pid_t is the same size as int. We've variously dealt
with this by casting pid_t to int or to unsigned long for printing
purposes; I went with the latter.
Fix uninitialized-variable warning in RestoreGUCState. This is
a live bug in some sense, but of no great significance given that
nobody is very likely to care what "line number" is associated with
a GUC that hasn't got a source file recorded.
statext_dependencies_load and statext_ndistinct_load were not up to snuff,
in addition to being randomly different from each other. In detail:
* Deserialize the fetched bytea value before releasing the syscache
entry, not after. This mistake causes visible regression test failures
when running with -DCATCACHE_FORCE_RELEASE. Since it's not exposed by
-DCLOBBER_CACHE_ALWAYS, I think there may be no production hazard here
at present, but it's at least a latent bug.
* Use DatumGetByteaPP not DatumGetByteaP to save a detoasting cycle
for short stats values; the deserialize function has to be, and is,
prepared for short-header values since its other caller uses PP.
* Use a test-and-elog for null stats values in both functions, rather
than a test-and-elog in one case and an Assert in the other. Perhaps
Asserts would be sufficient in both cases, but I don't see a good
argument for them being different.
* Minor cosmetic changes to make these functions more visibly alike.
Backpatch to v10 where this code came in.
Amit Langote, minor additional hacking by me
Discussion: https://postgr.es/m/1349aabb-3a1f-6675-9fc0-65e2ce7491dd@lab.ntt.co.jp
There were three related issues:
* BufFileAppend() incorrectly reset the seek position on the 'source' file.
As a result, if you had called BufFileRead() on the file before calling
BufFileAppend(), it got confused, and subsequent calls would read/write
at wrong position.
* BufFileSize() did not work with files opened with BufFileOpenShared().
* FileGetSize() only worked on temporary files.
To fix, change the way BufFileSize() works so that it works on shared
files. Remove FileGetSize() altogether, as it's no longer needed. Remove
buffilesize from TapeShare struct, as the leader process can simply call
BufFileSize() to get the tape's size, there's no need to pass it through
shared memory anymore.
Discussion: https://www.postgresql.org/message-id/CAH2-WznEDYe_NZXxmnOfsoV54oFkTdMy7YLE2NPBLuttO96vTQ@mail.gmail.com
Tom's earlier commit in 41c912cad1 didn't update a few cases that
are only encountered with the non-standard --with-llvm config
flag. Additionally there's also one case that appears to be a
deficiency in gcc's (up to trunk as of a few days ago) detection of
"fallthrough" comments - changing the placement slightly fixes that.
Author: Andres Freund
Discussion: https://postgr.es/m/20180502003239.wfnqu7ekz7j7imm4@alap3.anarazel.de
Recent gcc can warn about switch-case fall throughs that are not
explicitly labeled as intentional. This seems like a good thing,
so clean up the warnings exposed thereby by labeling all such
cases with comments that gcc will recognize.
In files that already had one or more suitable comments, I generally
matched the existing style of those. Otherwise I went with
/* FALLTHROUGH */, which is one of the spellings approved at the
more-restrictive-than-default level -Wimplicit-fallthrough=4.
(At the default level you can also spell it /* FALL ?THRU */,
and it's not picky about case. What you can't do is include
additional text in the same comment, so some existing comments
containing versions of this aren't good enough.)
Testing with gcc 8.0.1 (Fedora 28's current version), I found that
I also had to put explicit "break"s after elog(ERROR) or ereport(ERROR);
apparently, for this purpose gcc doesn't recognize that those don't
return. That seems like possibly a gcc bug, but it's fine because
in most places we did that anyway; so this amounts to a visit from the
style police.
Discussion: https://postgr.es/m/15083.1525207729@sss.pgh.pa.us
Previously a tuple that has been moved to a different partition (see
f16241bef7), set the block number on the old tuple to an invalid
value to indicate that fact. But the tuple offset was left
untouched. That turned out to trigger a wal_consistency_checking
failure as reported by Peter Geoghegan, as the offset wasn't
always overwritten during WAL replay.
Heikki observed that we're wasting valuable data by not putting
information also in the offset. Thus set that to
MovedPartitionsOffsetNumber when a tuple indicates it has moved.
We continue to set the block number to MovedPartitionsBlockNumber, as
that seems more likely to cause problems for code not updated to know
about moved tuples.
As t_ctid's offset number is now always set, this refinement also
fixes the wal_consistency_checking issue.
This technically is a minor disk format break, with previously created
moved tuples not being recognized anymore. But since there not even
has been a beta release since f16241bef7c...
Reported-By: Peter Geoghegan
Author: Heikki Linnakangas, Amul Sul
Discussion: https://postgr.es/m/CAH2-Wzm9ty+1BX7-GMNJ=xPRg67oJTVeDNdA9LSyJJtMgRiCMA@mail.gmail.com
Without these fixes, changes to the inserted tuple made by remote
triggers are ignored when building local RETURNING tuples.
In the core code, call ExecInitRoutingInfo at a later point from
within ExecInitPartitionInfo so that the FDW callback gets invoked
after the returning list has been built. But move CheckValidResultRel
out of ExecInitRoutingInfo so that it can happen at an earlier stage.
In postgres_fdw, refactor assorted deparsing functions to work with
the RTE rather than the PlannerInfo, which saves us having to
construct a fake PlannerInfo in cases where we don't have a real one.
Then, we can pass down a constructed RTE that yields the correct
deparse result when no real one exists. Unfortunately, this
necessitates a hack that understands how the core code manages RT
indexes for update tuple routing, which is ugly, but we don't have a
better idea right now.
Original report, analysis, and patch by Etsuro Fujita. Heavily
refactored by me. Then worked over some more by Amit Langote.
Discussion: http://postgr.es/m/5AD4882B.10002@lab.ntt.co.jp
Revert the map/unmap dance I tried in commit 73042b8d1; that helps
not at all.
Instead, speculate that the unwanted allocation is being done on
another thread, and thus timing variations explain the apparent
unpredictability. Temporarily add a 1-second sleep before the
VirtualFree call, in hopes that any such other threads will
quiesce and not jog our elbow.
This is obviously not a desirable long-term fix, but as a means of
investigation it seems useful.
Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us
The idea here is to get Windows' userspace infrastructure to allocate
whatever space it needs for MapViewOfFileEx() before we release the
locked-down space that we want to map the shared memory block into.
This is a fairly brute-force attempt, and would likely (for example)
fail with large shared memory on 32-bit Windows. We could perhaps
ameliorate that by mapping only part of the shared memory block in
this way, but for the moment I just want to see if this approach
will fix dory's problem.
Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us
Rather than elog'ing immediately, push the map data into a preallocated
StringInfo. Perhaps this will prevent some of the mid-operation
allocations that are evidently happening now.
Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us
The code previously undefined isnan because of a compiler warning on
MinGW. Since we now need to use isnan, we can't do that anymore.
We might need a different solution if the compiler warning is too
annoying.
When due to publication configuration, a TRUNCATE change ends up with
zero tables to be published, don't send the message out, just skip it.
It's not wrong, but obviously useless overhead.
This code is evidently allocating memory and thus confusing matters
even more. Let's see whether we can learn anything with
just VirtualQuery.
Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us
This morning's results from buildfarm member dory make it pretty
clear that something is getting mapped into the just-freed space,
but not what that something is. Replace my minimalistic probes
with a full dump of the process address space and module space,
based on Noah's work at
<20170403065106.GA2624300%40tornado.leadboat.com>
This is all (probably) to get reverted once we have fixed the
problem, but for now we need information.
Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us
While looking at a recent buildfarm failure in the ecpg tests, I wondered
why the pg_regress output claimed the stderr part of the test failed, when
the regression diffs were clearly for the stdout part. Looking into it,
the reason is that pg_regress.c's logic for iterating over three parallel
lists is wrong, and has been wrong since it was written: it advances the
"tag" pointer at a different place in the loop than the other two pointers.
Fix that.
After some thought about the info captured so far, it seems possible
that MapViewOfFileEx is itself causing some DLL to get loaded into
the space just freed by VirtualFree. The previous commit here didn't
capture enough info to really prove the case for that, so let's add
one more VirtualQuery in between those steps. Also, be sure to
capture the post-Map state before we emit any log entries, just in
case elog() is invoking some code not previously loaded.
Discussion: https://postgr.es/m/25495.1524517820@sss.pgh.pa.us
Buildfarm results show that the modern POSIX rule that 1 ^ NaN = 1 is not
honored on *BSD until relatively recently, and really old platforms don't
believe that NaN ^ 0 = 1 either. (This is unsurprising, perhaps, since
SUSv2 doesn't require either behavior.) In hopes of getting to platform
independent behavior, let's deal with all the NaN-input cases explicitly
in dpow().
Note that numeric_power() doesn't know either of these special cases.
But since that behavior is platform-independent, I think it should be
addressed separately, and probably not back-patched.
Discussion: https://postgr.es/m/75DB81BEEA95B445AE6D576A0A5C9E936A73E741@BPXM05GP.gisp.nec.co.jp
DST law changes in Palestine and Antarctica (Casey Station). Historical
corrections for Portugal and its colonies, as well as Enderbury, Jamaica,
Turks & Caicos Islands, and Uruguay.
Per spec, the result of power() should be NaN if either input is NaN.
It appears that on some versions of Windows, the libc function does
return NaN, but it also sets errno = EDOM, confusing our code that
attempts to work around shortcomings of other platforms. Hence, add
guard tests to avoid substituting a wrong result for the right one.
It's been like this for a long time (and the odd behavior only appears
in older MSVC releases, too) so back-patch to all supported branches.
Dang Minh Huong, reviewed by David Rowley
Discussion: https://postgr.es/m/75DB81BEEA95B445AE6D576A0A5C9E936A73E741@BPXM05GP.gisp.nec.co.jp
The point of this is not really to remove redundancy in pg_language.dat;
with only three entries, it's hardly worth it. Rather, it is to get
to a point where there are exactly zero hard-coded numeric pg_proc OID
references in the catalog .dat files. The lanvalidator column was the
only remaining location of such references, and it seems like a good
thing for future-proofing reasons to make it not be a special case.
There are still a few places in the .dat files with numeric OID references
to other catalogs, but after review I don't see any that seem worth
changing at present. In each case there are just too few entries to make
it worth the trouble to create lookup infrastructure.
This doesn't change the emitted postgres.bki file, so no catversion bump.
This change makes this module act more like most of our other low-level
resource management modules. It's a caller error if something is not
explicitly closed by the end of a successful transaction, so issue
a WARNING about it. This would not actually have caught the file leak
bug fixed in commit 231bcd080, because that was in a transaction-abort
path; but it still seems like a good, and pretty cheap, cross-check.
Discussion: https://postgr.es/m/152056616579.4966.583293218357089052@wrigleys.postgresql.org
