Although the postmaster doesn't currently create a self-pipe or any
latches, there's discussion of it doing so in future. It's also
conceivable that a shared_preload_libraries extension would try to
create such a thing in the postmaster process today. In that case
the self-pipe FDs would be inherited by forked child processes.
latch.c was entirely unprepared for such a case and could suffer an
assertion failure, or worse try to use the inherited pipe if somebody
called WaitLatch without having called InitializeLatchSupport in that
process. Make it keep track of whether InitializeLatchSupport has been
called in the *current* process, and do the right thing if state has
been inherited from a parent.
Apply FD_CLOEXEC to file descriptors created in latch.c (the self-pipe,
as well as epoll event sets). This ensures that child processes spawned
in backends, the archiver, etc cannot accidentally or intentionally mess
with these FDs. It also ensures that we end up with the right state
for the self-pipe in EXEC_BACKEND processes, which otherwise wouldn't
know to close the postmaster's self-pipe FDs.
Back-patch to 9.6, mainly to keep latch.c looking similar in all branches
it exists in.
Discussion: https://postgr.es/m/8322.1493240739@sss.pgh.pa.us
Previously, maybe_start_bgworker() would launch at most one bgworker
process per call, on the grounds that the postmaster might otherwise
neglect its other duties for too long. However, that seems overly
conservative, especially since bad effects only become obvious when
many hundreds of bgworkers need to be launched at once. On the other
side of the coin is that the existing logic could result in substantial
delay of bgworker launches, because ServerLoop isn't guaranteed to
iterate immediately after a signal arrives. (My attempt to fix that
by using pselect(2) encountered too many portability question marks,
and in any case could not help on platforms without pselect().)
One could also question the wisdom of using an O(N^2) processing
method if the system is intended to support so many bgworkers.
As a compromise, allow that function to launch up to 100 bgworkers
per call (and in consequence, rename it to maybe_start_bgworkers).
This will allow any normal parallel-query request for workers
to be satisfied immediately during sigusr1_handler, avoiding the
question of whether ServerLoop will be able to launch more promptly.
There is talk of rewriting the postmaster to use a WaitEventSet to
avoid the signal-response-delay problem, but I'd argue that this change
should be kept even after that happens (if it ever does).
Backpatch to 9.6 where parallel query was added. The issue exists
before that, but previous uses of bgworkers typically aren't as
sensitive to how quickly they get launched.
Discussion: https://postgr.es/m/4707.1493221358@sss.pgh.pa.us
Objects in an extension are shippable to a foreign server if the
extension is part of the foreign server definition's shippable
extensions list. But this was not properly considered in some cases
when checking whether a join condition can be pushed to a foreign server
and the join condition uses an object from a shippable extension. So
the join would never be pushed down in those cases.
So, the list of extensions needs to be made available in fpinfo of the
relation being considered to be pushed down before any expressions are
assessed for being shippable. Fix foreign_join_ok() to do that for a
join relation.
David Rowley and Ashutosh Bapat, per report from David Rowley
reduced version of patch 332bec1e60 for
backpatch to 9.6, first release with join push down
This reverts commit b9515b6287.
Buildfarm results suggest that some platforms have versions of pselect(2)
that are not merely non-atomic, but flat out non-functional. Revert the
use-pselect patch to confirm this diagnosis (and exclude the no-SA_RESTART
patch as the source of trouble). If it's so, we should probably look into
blacklisting specific platforms that have broken pselect.
Discussion: https://postgr.es/m/9696.1493072081@sss.pgh.pa.us
Traditionally we've unblocked signals, called select(2), and then blocked
signals again. The code expects that the select() will be cancelled with
EINTR if an interrupt occurs; but there's a race condition, which is that
an already-pending signal will be delivered as soon as we unblock, and then
when we reach select() there will be nothing preventing it from waiting.
This can result in a long delay before we perform any action that
ServerLoop was supposed to have taken in response to the signal. As with
the somewhat-similar symptoms fixed by commit 893902085, the main practical
problem is slow launching of parallel workers. The window for trouble is
usually pretty short, corresponding to one iteration of ServerLoop; but
it's not negligible.
To fix, use pselect(2) in place of select(2) where available, as that's
designed to solve exactly this problem. Where not available, we continue
to use the old way, and are no worse off than before.
pselect(2) has been required by POSIX since about 2001, so most modern
platforms should have it. A bigger portability issue is that some
implementations are said to be non-atomic, ie pselect() isn't really
any different from unblock/select/reblock. Still, we're no worse off
than before on such a platform.
There is talk of rewriting the postmaster to use a WaitEventSet and
not do signal response work in signal handlers, at which point this
could be reverted, since we'd be using a self-pipe to solve the race
condition. But that's not happening before v11 at the earliest.
Back-patch to 9.6. The problem exists much further back, but the
worst symptom arises only in connection with parallel query, so it
does not seem worth taking any portability risks in older branches.
Discussion: https://postgr.es/m/9205.1492833041@sss.pgh.pa.us
The postmaster keeps signals blocked everywhere except while waiting
for something to happen in ServerLoop(). The code expects that the
select(2) will be cancelled with EINTR if an interrupt occurs; without
that, followup actions that should be performed by ServerLoop() itself
will be delayed. However, some platforms interpret the SA_RESTART
signal flag as meaning that they should restart rather than cancel
the select(2). Worse yet, some of them restart it with the original
timeout delay, meaning that a steady stream of signal interrupts can
prevent ServerLoop() from iterating at all if there are no incoming
connection requests.
Observable symptoms of this, on an affected platform such as HPUX 10,
include extremely slow parallel query startup (possibly as much as
30 seconds) and failure to update timestamps on the postmaster's sockets
and lockfiles when no new connections arrive for a long time.
We can fix this by running the postmaster's signal handlers without
SA_RESTART. That would be quite a scary change if the range of code
where signals are accepted weren't so tiny, but as it is, it seems
safe enough. (Note that postmaster children do, and must, reset all
the handlers before unblocking signals; so this change should not
affect any child process.)
There is talk of rewriting the postmaster to use a WaitEventSet and
not do signal response work in signal handlers, at which point it might
be appropriate to revert this patch. But that's not happening before
v11 at the earliest.
Back-patch to 9.6. The problem exists much further back, but the
worst symptom arises only in connection with parallel query, so it
does not seem worth taking any portability risks in older branches.
Discussion: https://postgr.es/m/9205.1492833041@sss.pgh.pa.us
This corner case didn't behave nicely at all: the postmaster would
(partially) update its state as though the process had started
successfully, and be quite confused thereafter. Fix it to act
like the worker had crashed, instead.
In passing, refactor so that do_start_bgworker contains all the
state-change logic for bgworker launch, rather than just some of it.
Back-patch as far as 9.4. 9.3 contains similar logic, but it's just
enough different that I don't feel comfortable applying the patch
without more study; and the use of bgworkers in 9.3 was so small
that it doesn't seem worth the extra work.
transam/parallel.c is still entirely unprepared for the possibility
of bgworker startup failure, but that seems like material for a
separate patch.
Discussion: https://postgr.es/m/4905.1492813727@sss.pgh.pa.us
This seems to be largely cosmetic, avoiding valgrind bleats and the
like. The uninitialized padding influences the CRC of the on-disk
entry, but because it's also used when verifying the CRC, that doesn't
cause spurious failures. Backpatch nonetheless.
It's a bit unfortunate that contrib/test_decoding/sql/replorigin.sql
doesn't exercise the checkpoint path, but checkpoints are fairly
expensive on weaker machines, and we'd have to stop/start for that to
be meaningful.
Author: Andres Freund
Discussion: https://postgr.es/m/20170422183123.w2jgiuxtts7qrqaq@alap3.anarazel.de
Backpatch: 9.5, where replication origins were introduced
ProcessTwoPhaseBuffer (formerly StandbyRecoverPreparedTransactions)
mixed up the parent and child XIDs when calling SubTransSetParent to
record the transactions' relationship in pg_subtrans.
Remarkably, analysis by Simon Riggs suggests that this doesn't lead to
visible problems (at least, not in non-Assert builds). That might
explain why we'd not noticed it before. Nonetheless, it's surely wrong.
This code was born broken, so back-patch to all supported branches.
Discussion: https://postgr.es/m/20110.1492905318@sss.pgh.pa.us
archive_command and restore_command need to refer to Windows paths, not
Msys virtual file system paths, as postgres is completely unaware of the
latter, so prefix them with the Windows path to the virtual file system
root. Clean psql output of carriage returns.
PostgresNode blithely ignored the exit status of pg_ctl, and in general
made no effort to be sure that the server was running when it should be.
This caused it to miss server crashes, which is a serious shortcoming
in a test scaffold. Make it complain if pg_ctl fails, and modify the
start and stop logic to complain if the server doesn't start, or doesn't
stop, when expected.
Also, have it turn off the "restart_after_crash" configuration parameter
in created clusters, as bitter experience has shown that leaving that on
can mask crashes too.
We might at some point need variant functions that allow for, eg,
server start failure to be expected. But no existing test case appears
to want that, and it surely shouldn't be the default behavior.
Note that this *will* break the buildfarm, as it will expose known
bugs that the previous testing failed to. I'm committing it despite
that, to verify that we get the expected failures in the buildfarm
not just in manual testing.
Back-patch into 9.6 where PostgresNode was introduced. (The 9.6
branch is not expected to show any failures.)
Discussion: https://postgr.es/m/21432.1492886428@sss.pgh.pa.us
Although the documentation for append_conf said clearly that it didn't
add a newline, many test authors seem to have forgotten that ... or maybe
they just consulted the example at the top of the POD documentation,
which clearly shows adding a config entry without bothering to add a
trailing newline. The worst part of that is that it works, as long as
you don't do it more than once, since the backend isn't picky about
whether config files end with newlines. So there's not a strong forcing
function reminding test authors not to do it like that. Upshot is that
this is a terribly fragile way to go about things, and there's at least
one existing test case that is demonstrably broken and not testing what
it thinks it is.
Let's just make append_conf append a newline, instead; that is clearly
way safer than the old definition.
I also cleaned up a few call sites that were unnecessarily ugly.
(I left things alone in places where it's plausible that additional
config lines would need to be added someday.)
Back-patch the change in append_conf itself to 9.6 where it was added,
as having a definitional inconsistency between branches would obviously
be pretty hazardous for back-patching TAP tests. The other changes are
just cosmetic and don't need to be back-patched.
Discussion: https://postgr.es/m/19751.1492892376@sss.pgh.pa.us
The reference "That is the topic of the next section." has been
incorrect since the materialized views documentation got inserted
between the section "rules-views" and "rules-update".
Author: Zertrin <postgres_wiki@zertrin.org>
The POSIX standard does not say that the success return value for
fcntl(F_SETFD) and fcntl(F_SETFL) is zero; it says only that it's not -1.
We had several calls that were making the stronger assumption. Adjust
them to test specifically for -1 for strict spec compliance.
The standard further leaves open the possibility that the O_NONBLOCK
flag bit is not the only active one in F_SETFL's argument. Formally,
therefore, one ought to get the current flags with F_GETFL and store
them back with only the O_NONBLOCK bit changed when trying to change
the nonblock state. In port/noblock.c, we were doing the full pushup
in pg_set_block but not in pg_set_noblock, which is just weird. Make
both of them do it properly, since they have little business making
any assumptions about the socket they're handed. The other places
where we're issuing F_SETFL are working with FDs we just got from
pipe(2), so it's reasonable to assume the FDs' properties are all
default, so I didn't bother adding F_GETFL steps there.
Also, while pg_set_block deserves some points for trying to do things
right, somebody had decided that it'd be even better to cast fcntl's
third argument to "long". Which is completely loony, because POSIX
clearly says the third argument for an F_SETFL call is "int".
Given the lack of field complaints, these missteps apparently are not
of significance on any common platforms. But they're still wrong,
so back-patch to all supported branches.
Discussion: https://postgr.es/m/30882.1492800880@sss.pgh.pa.us
We were applying the use_physical_tlist optimization to all relation
scan plans, even those implemented by custom scan providers. However,
that's a bad idea for a couple of reasons. The custom provider might
be unable to provide columns that it hadn't expected to be asked for
(for example, the custom scan might depend on an index-only scan).
Even more to the point, there's no good reason to suppose that this
"optimization" is a win for a custom scan; whatever the custom provider
is doing is likely not based on simply returning physical heap tuples.
(As a counterexample, if the custom scan is an interface to a column store,
demanding all columns would be a huge loss.) If it is a win, the custom
provider could make that decision for itself and insert a suitable
pathtarget into the path, anyway.
Per discussion with Dmitry Ivanov. Back-patch to 9.5 where custom scan
support was introduced. The argument that the custom provider can adjust
the behavior by changing the pathtarget only applies to 9.6+, but on
balance it seems more likely that use_physical_tlist will hurt custom
scans than help them.
Discussion: https://postgr.es/m/e29ddd30-8ef9-4da5-a50b-2bb7b8c7198d@postgrespro.ru
In standard non-Windows builds, there's no particular reason to care what
address the kernel chooses to map the shared memory segment at. However,
when building with EXEC_BACKEND, there's a risk that the chosen address
won't be available in all child processes. Linux with ASLR enabled (which
it is by default) seems particularly at risk because it puts shmem segments
into the same area where it maps shared libraries. We can work around
that by specifying a mapping address that's outside the range where
shared libraries could get mapped. On x86_64 Linux, 0x7e0000000000
seems to work well.
This is only meant for testing/debugging purposes, so it doesn't seem
necessary to go as far as providing a GUC (or any user-visible
documentation, though we might change that later). Instead, it's just
controlled by setting an environment variable PG_SHMEM_ADDR to the
desired attach address.
Back-patch to all supported branches, since the point here is to
remove intermittent buildfarm failures on EXEC_BACKEND animals.
Owners of affected animals will need to add a suitable setting of
PG_SHMEM_ADDR to their build_env configuration.
Discussion: https://postgr.es/m/7036.1492231361@sss.pgh.pa.us
This back-patches commit 32470825d3
into 9.6, primarily to make buildfarm member culicidae happy.
Unlike the HEAD patch, avoid changing the existing API of
CreateParallelContext; instead we just switch to using
CreateParallelContextForExternalFunction, even for core functions.
Petr Jelinek, with a bunch of basically-cosmetic adjustments by me
Discussion: https://postgr.es/m/548f9c1d-eafa-e3fa-9da8-f0cc2f654e60@2ndquadrant.com
Commit 9e43e8714 turns out to have been insufficient: not only is it
necessary to track tentative parent links while considering a set of
arc removals, but it's necessary to track tentative flag additions
as well. This is because we always merge arc target states into
arc source states; therefore, when considering a merge of the final
state with some other, it is the other state that will acquire a new
TSTATE_FIN bit. If there's another arc for the same color trigram
that would cause merging of that state with the initial state, we
failed to recognize the problem. The test cases for the prior commit
evidently only exercised situations where a tentative merge with the
initial state occurs before one with the final state. If it goes the
other way around, we'll happily merge the initial and final states,
either producing a broken final graph that would never match anything,
or triggering the Assert added by the prior commit.
It's tempting to consider switching the merge direction when the merge
involves the final state, but I lack the time to analyze that idea in
detail. Instead just keep track of the flag changes that would result
from proposed merges, in the same way that the prior commit tracked
proposed parent links.
Along the way, add some more debugging support, because I'm not entirely
confident that this is the last bug here. And tweak matters so that
the transformed.dot file uses small integers rather than pointer values
to identify states; that makes it more readable if you're just eyeballing
it rather than fooling with Graphviz. And rename a couple of identically
named struct fields to reduce confusion.
Per report from Corey Csuhta. Add a test case based on his example.
(Note: this case does not trigger the bug under 9.3, apparently because
its different measurement of costs causes it to stop merging states before
it hits the failure. I spent some time trying to find a variant that would
fail in 9.3, without success; but I'm sure such cases exist.)
Like the previous patch, back-patch to 9.3 where this code was added.
Report: https://postgr.es/m/E2B01A4B-4530-406B-8D17-2F67CF9A16BA@csuhta.com
regexport.c thought it could just ignore LACON arcs, but the correct
behavior is to treat them as satisfiable while consuming zero input
(rather reminiscently of commit 9f1e642d5). Otherwise, the emitted
simplified-NFA representation may contain no paths leading from initial
to final state, which unsurprisingly confuses pg_trgm, as seen in
bug #14623 from Jeff Janes.
Since regexport's output representation has no concept of an arc that
consumes zero input, recurse internally to find the next normal arc(s)
after any LACON transitions. We'd be forced into changing that
representation if a LACON could be the last arc reaching the final
state, but fortunately the regex library never builds NFAs with such
a configuration, so there always is a next normal arc.
Back-patch to 9.3 where this logic was introduced.
Discussion: https://postgr.es/m/20170413180503.25948.94871@wrigleys.postgresql.org
Previously the description about pg_stat_progress_vacuum was in the table
of "Collected Statistics Views" in the doc. But since it repors dynamic
information, i.e., the current progress of VACUUM, its description should be
in the table of "Dynamic Statistics Views".
Back-patch to 9.6 where pg_stat_progress_vacuum was added.
Author: Amit Langote
Discussion: http://postgr.es/m/7ab51b59-8d4d-6193-c60a-b75f222efb12@lab.ntt.co.jp
This extends the castNode() notation introduced by commit 5bcab1114 to
provide, in one step, extraction of a list cell's pointer and coercion to
a concrete node type. For example, "lfirst_node(Foo, lc)" is the same
as "castNode(Foo, lfirst(lc))". Almost half of the uses of castNode
that have appeared so far include a list extraction call, so this is
pretty widely useful, and it saves a few more keystrokes compared to the
old way.
As with the previous patch, back-patch the addition of these macros to
pg_list.h, so that the notation will be available when back-patching.
Patch by me, after an idea of Andrew Gierth's.
Discussion: https://postgr.es/m/14197.1491841216@sss.pgh.pa.us
As reported by Sean Johnston in bug #14614, since 9.6 the planner can fail
due to trying to look up the referent of a Var with varno 0. This happens
because we generate such Vars in generate_append_tlist, for lack of any
better way to describe the output of a SetOp node. In typical situations
nothing really cares about that, but given nested set-operation queries
we will call estimate_num_groups on the output of the subquery, and that
wants to know what a Var actually refers to. That logic used to look at
subquery->targetList, but in commit 3fc6e2d7f I'd switched it to look at
subroot->processed_tlist, ie the actual output of the subquery plan not the
parser's idea of the result. It seemed like a good idea at the time :-(.
As a band-aid fix, change it back.
Really we ought to have an honest way of naming the outputs of SetOp steps,
which suggests that it'd be a good idea for the parser to emit an RTE
corresponding to each one. But that's a task for another day, and it
certainly wouldn't yield a back-patchable fix.
Report: https://postgr.es/m/20170407115808.25934.51866@wrigleys.postgresql.org
<selinux/label.h> includes <stdbool.h>, which creates an incompatible
We don't care if <stdbool.h> redefines "true"/"false"; those are close
enough.
Complaint and initial patch by Mike Palmiotto. Final approach per
Tom Lane's suggestion, as discussed on hackers. Backpatching to
all supported branches.
Discussion: https://postgr.es/m/flat/623bcaae-112e-ced0-8c22-a84f75ae0c53%40joeconway.com
HandleFunctionRequest() is no longer responsible for reading the protocol
message from the client, since commit 2b3a8b20c2. Fix the outdated
comments.
HandleFunctionRequest() now always returns 0, because the code that used
to return EOF was moved in 2b3a8b20c2. Therefore, the caller no longer
needs to check the return value.
Reported by Andres Freund. Backpatch to all supported versions, even though
this doesn't have any user-visible effect, to make backporting future
patches in this area easier.
Discussion: https://www.postgresql.org/message-id/20170405010525.rt5azbya5fkbhvrx@alap3.anarazel.de
When using integer timestamps, the interval-comparison functions tried
to compute the overall magnitude of an interval as an int64 number of
microseconds. As reported by Frazer McLean, this overflows for intervals
exceeding about 296000 years, which is bad since we nominally allow
intervals many times larger than that. That results in wrong comparison
results, and possibly in corrupted btree indexes for columns containing
such large interval values.
To fix, compute the magnitude as int128 instead. Although some compilers
have native support for int128 calculations, many don't, so create our
own support functions that can do 128-bit addition and multiplication
if the compiler support isn't there. These support functions are designed
with an eye to allowing the int128 code paths in numeric.c to be rewritten
for use on all platforms, although this patch doesn't do that, or even
provide all the int128 primitives that will be needed for it.
Back-patch as far as 9.4. Earlier releases did not guard against overflow
of interval values at all (commit 146604ec4 fixed that), so it seems not
very exciting to worry about overly-large intervals for them.
Before 9.6, we did not assume that unreferenced "static inline" functions
would not draw compiler warnings, so omit functions not directly referenced
by timestamp.c, the only present consumer of int128.h. (We could have
omitted these functions in HEAD too, but since they were written and
debugged on the way to the present patch, and they look likely to be needed
by numeric.c, let's keep them in HEAD.) I did not bother to try to prevent
such warnings in a --disable-integer-datetimes build, though.
Before 9.5, configure will never define HAVE_INT128, so the part of
int128.h that exploits a native int128 implementation is dead code in the
9.4 branch. I didn't bother to remove it, thinking that keeping the file
looking similar in different branches is more useful.
In HEAD only, add a simple test harness for int128.h in src/tools/.
In back branches, this does not change the float-timestamps code path.
That's not subject to the same kind of overflow risk, since it computes
the interval magnitude as float8. (No doubt, when this code was originally
written, overflow was disregarded for exactly that reason.) There is a
precision hazard instead :-(, but we'll avert our eyes from that question,
since no complaints have been reported and that code's deprecated anyway.
Kyotaro Horiguchi and Tom Lane
Discussion: https://postgr.es/m/1490104629.422698.918452336.26FA96B7@webmail.messagingengine.com
This backpatches 51e26c9 and 7220c7b, including both documentation
updates clarifying the checkpoints at the beginning of base backups and
the messages in verbose and progress mdoe of pg_basebackup.
Author: Michael Banck
Discussion: https://postgr.es/m/21444.1488142764%40sss.pgh.pa.us
Commit 45be99f8cd removed GatherPath's
num_workers field, but this is entirely bogus. Normally, a path's
parallel_workers flag is supposed to indicate the number of workers
that it wants, and should be 0 for a non-partial path. In that
commit, I mistakenly thought that GatherPath could also use that field
to indicate the number of workers that it would try to start, but
that's disastrous, because then it can propagate up to higher nodes in
the plan tree, which will then get incorrect rowcounts because the
parallel_workers flag is involved in computing those values. Repair
by putting the separate field back.
Report by Tomas Vondra. Patch by me, reviewed by Amit Kapila.
Discussion: http://postgr.es/m/f91b4a44-f739-04bd-c4b6-f135bd643669@2ndquadrant.com
On EXEC_BACKEND builds, this can fail if ASLR is in use.
Backpatch to 9.5. On master, completely remove the bgw_main field
completely, since there is no situation in which it is safe for an
EXEC_BACKEND build. On 9.6 and 9.5, leave the field intact to avoid
breaking things for third-party code that doesn't care about working
under EXEC_BACKEND. Prior to 9.5, there are no in-core bgworker
entrypoints.
Petr Jelinek, reviewed by me.
Discussion: http://postgr.es/m/09d8ad33-4287-a09b-a77f-77f8761adb5e@2ndquadrant.com
Previously a detailed activity report by VACUUM VERBOSE ANALYZE was
described as an example of VACUUM in docs. But it had been obsolete
for a long time. For example, commit feb4f44d29
updated the content of that activity report in 2003, but we had
forgotten to update the example.
So basically we need to update the example. But since no one cared
about the details of VACUUM output and complained about that mistake
for such long time, per discussion on hackers, we decided to get rid
of the detailed activity report from the example and simplify it.
Back-patch to all supported versions.
Reported by Masahiko Sawada, patch by me.
Discussion: https://postgr.es/m/CAD21AoAGA2pB3p-CWmTkxBsbkZS1bcDGBLcYVcvcDxspG_XAfA@mail.gmail.com
We were assigning values near 255 through "char *" pointers. On machines
where char is signed, that's not entirely kosher, and it's reasonable
for compilers to warn about it.
A better solution would be to change the pointer type to "unsigned char *",
but that would be vastly more invasive. For the moment, let's just apply
this simple backpatchable solution.
Aleksander Alekseev
Discussion: https://postgr.es/m/20170220141239.GD12278@e733.localdomain
Discussion: https://postgr.es/m/2839.1490714708@sss.pgh.pa.us
The compiler is entitled to store a char[] local variable with no
particular alignment requirement. Our RADIUS code cavalierly took such
a local variable and cast its address to a struct type that does have
alignment requirements. On an alignment-picky machine this would lead
to bus errors. To fix, declare the local variable honestly, and then
cast its address to char * for use in the I/O calls.
Given the lack of field complaints, there must be very few if any
people affected; but nonetheless this is a clear portability issue,
so back-patch to all supported branches.
Noted while looking at a Coverity complaint in the same code.
Commit 7aea8e4f2d allowed a parallel
plan to be generated when for a RETURN QUERY or RETURN QUERY EXECUTE
statement in a PL/pgsql block, but that's a bad idea because plplgsql
asks the executor for 50 rows at a time. That means that we'll always
be running serially a plan that was intended for parallel execution,
which is not a good idea. Fix by not requesting a parallel plan from
the outset.
Per discussion, back-patch to 9.6. There is a slight risk that, due
to optimizer error, somebody could have a case where the parallel plan
executed serially is actually faster than the supposedly-best serial
plan, but the consensus seems to be that that's not sufficient
justification for leaving 9.6 unpatched.
Discussion: http://postgr.es/m/CA+TgmoZ_ZuH+auEeeWnmtorPsgc_SmP+XWbDsJ+cWvWBSjNwDQ@mail.gmail.com
Discussion: http://postgr.es/m/CA+TgmobXEhvHbJtWDuPZM9bVSLiTj-kShxQJ2uM5GPDze9fRYA@mail.gmail.com
The bug is that prior to --rate doCustom was always disconnect/reconnect
without exiting, but with rate it returns if it has to wait. However threadRun
test whether there is a connection before recalling doCustom, so it was never
called.
Bug is not existed in head branch because of refactoring at
12788ae49e, patch only 9.6
Author: Fabien Coelho
Reviewed-by: me
https://commitfest.postgresql.org/13/970/
Assert-enabled build crashes but without asserts it works by wrong way:
it may not reset forcing full page write and preventing from starting
exclusive backup with the same name as cancelled.
Patch replaces pair of booleans
nonexclusive_backup_running/exclusive_backup_running to single enum to
correctly describe backup state.
Backpatch to 9.6 where bug was introduced
Reported-by: David Steele
Authors: Michael Paquier, David Steele
Reviewed-by: Anastasia Lubennikova
https://commitfest.postgresql.org/13/1068/
This reverts commit 38bdba54a6, "Fix and
simplify check for whether we're running as Windows service". It turns out
that older versions of MinGW - like that on buildfarm member narwhal - do
not support the CheckTokenMembership() function. This replaces the
refactoring with a much smaller fix, to add a check for SE_GROUP_ENABLED to
pgwin32_is_service().
Only apply to back-branches, and keep the refactoring in HEAD. It's
unlikely that anyone is still really using such an old version of MinGW -
aside from narwhal - but let's not change the minimum requirements in
minor releases.
Discussion: https://www.postgresql.org/message-id/16609.1489773427@sss.pgh.pa.us
Patch: https://www.postgresql.org/message-id/CAB7nPqSvfu%3DKpJ%3DNX%2BYAHmgAmQdzA7N5h31BjzXeMgczhGCC%2BQ%40mail.gmail.com
of SP-GiST.
Bug exists since initial commit of box opclass for SP-GiST,
so backpath to 9.6
Author: Nikita Glukhov with minor editorization of tests by me
Reviewed-by: Kyotaro Horiguchi, Anastasia Lubennikova
https://commitfest.postgresql.org/13/981/
this makes buffer access strategy have no effect.
Change was a part of commit 48354581a4 during 9.6
release cycle, so backpath to 9.6
Reported-by: Jim Nasby
Author: Alexander Korotkov
Reviewed-by: Jim Nasby, Andres Freund
https://commitfest.postgresql.org/13/1029/
Windows apparently will not detect socket write-ready events unless a
preceding send attempt returned WSAEWOULDBLOCK. In many usage patterns
that's satisfied by the caller of WaitEvenSetWait(), but not always.
Apply the same solution that we already had in pgwin32_select(), namely to
perform a dummy WSASend() call with len=0. This will return WSAEWOULDBLOCK
if there's no buffer space (even though it could legitimately do nothing
and report success, which makes me a bit nervous about this solution;
but since it's been working fine in libpq, let's roll with it).
In passing, improve the comments about this in pgwin32_select(), and remove
duplicated code there.
Back-patch to 9.6 where WaitEventSetWait() was introduced. We might need
to back-patch something similar into predecessor code. But given the lack
of complaints so far, it's not clear that the case ever gets exercised
in the back branches, so I'm not going to expend effort on it right now.
This should resolve recurring failures on buildfarm member bowerbird,
which has been failing since 1e8a85009 went in.
Diagnosis and patch by Petr Jelinek, cosmetic adjustments by me.
Discussion: https://postgr.es/m/5b6a6d6d-fb45-0afb-2e95-5600063c3dbd@2ndquadrant.com
Concurrent auto-analyze could be holding a snapshot, affecting the
removal of deleted row versions. Remove the deletion to avoid this
happening. Per buildfarm.
In passing, make the test independent of assumptions of physical row
order, just out of sheer paranoia.
If the process token contains SECURITY_SERVICE_RID, but it has been
disabled by the SE_GROUP_USE_FOR_DENY_ONLY attribute, win32_is_service()
would incorrectly report that we're running as a service. That situation
arises, e.g. if postmaster is launched with a restricted security token,
with the "Log in as Service" privilege explicitly removed.
Replace the broken code with CheckProcessTokenMembership(), which does
this correctly. Also replace similar code in win32_is_admin(), even
though it got this right, for simplicity and consistency.
Per bug #13755, reported by Breen Hagan. Back-patch to all supported
versions. Patch by Takayuki Tsunakawa, reviewed by Michael Paquier.
Discussion: https://www.postgresql.org/message-id/20151104062315.2745.67143%40wrigleys.postgresql.org
presence of page pins, which leads to serious estimation errors in the
planner. This particularly affects small heavily-accessed tables,
especially where locking (e.g. from FK constraints) forces frequent
vacuums for mxid cleanup.
Fix by keeping separate track of pages whose live tuples were actually
counted vs. pages that were only scanned for freezing purposes. Thus,
reltuples can only be set to 0 if all pages of the relation were
actually counted.
Backpatch to all supported versions.
Per bug #14057 from Nicolas Baccelli, analyzed by me.
Discussion: https://postgr.es/m/20160331103739.8956.94469@wrigleys.postgresql.org
The original coding was trying to use a TypeName as a string Value,
which doesn't work; an oversight in my commit a61fd533. Repair.
Also, make sure we cover the broken case in the relevant test script.
Backpatch to 9.5.
Discussion: https://postgr.es/m/20170315151829.bhxsvrp75xdxhm3n@alvherre.pgsql
This could result in corruption of the init fork of an unlogged index
if the ambuildempty routine for that index used shared buffers to
create the init fork, which was true for brin, gin, gist, and hash
indexes.
Patch by me, based on an earlier patch by Michael Paquier, who also
reviewed this one. This also incorporates an idea from Artur
Zakirov.
Discussion: http://postgr.es/m/CACYUyc8yccE4xfxhqxfh_Mh38j7dRFuxfaK1p6dSNAEUakxUyQ@mail.gmail.com
Rather than waiting around for statement_timeout to expire, we can just
try to take the table's lock in nowait mode. This saves some fraction
under 4 seconds when running this test with prepared xacts available,
and it guards against timeout-expired-anyway failures on very slow
machines when prepared xacts are not available, as seen in a recent
failure on axolotl for instance.
This approach could fail if autovacuum were to take an exclusive lock
on the test table concurrently, but there's no reason for it to do so.
Since the main point here is to improve stability in the buildfarm,
back-patch to all supported branches.
The problem was that "begin transaction" was issued automatically
before executing COMMIT/ROLLBACK PREPARED if not in auto commit. This fix by
Masahiko Sawada fixes this.
