These functions have been marked parallel safe, but the buildfarm's
response to commit e2933a6e1 exposed the flaw in that thinking:
if you try to use them on a temporary table, and they run inside
a parallel worker, they'll fail with "cannot access temporary tables
during a parallel operation".
Fix that by marking them parallel restricted instead. Maybe someday
we'll have a better answer and can reverse this decision.
Back-patch to v15. To go back further, we'd have to devise variant
versions of pre-1.10 pageinspect versions. Given the lack of field
complaints, it doesn't seem worth the trouble. We'll just deem
this case unsupported pre-v15. (If anyone does complain, it might
be good enough to update the markings manually in their DBs.)
Discussion: https://postgr.es/m/E1ox94a-000EHu-VH@gemulon.postgresql.org
The postmaster normally sends SIGQUIT to force-terminate its
child processes after a child crash or immediate-stop request.
If that doesn't result in child exit within a few seconds,
we follow it up with SIGKILL. This patch provides GUC flags
that allow either of these signals to be replaced with SIGABRT.
On typically-configured Unix systems, that will result in a
core dump being produced for each such child. This can be
useful for debugging problems, although it's not something you'd
want to have on in production due to the risk of disk space
bloat from lots of core files.
The old postmaster -T switch, which sent SIGSTOP in place of
SIGQUIT, is changed to be the same as send_abort_for_crash.
As far as I can tell from the code comments, the intent of
that switch was just to block things for long enough to force
core dumps manually, which seems like an unnecessary extra step.
(Maybe at the time, there was no way to get most kernels to
produce core files with per-PID names, requiring manual core
file renaming after each one. But now it's surely the hard way.)
I also took the opportunity to remove the old postmaster -n
(skip shmem reinit) switch, which hasn't actually done anything
in decades, though the documentation still claimed it did.
Discussion: https://postgr.es/m/2251016.1668797294@sss.pgh.pa.us
pageinspect has occasionally failed on slow buildfarm members,
with symptoms indicating that the expected effects of VACUUM
FREEZE didn't happen. This is presumably because a background
transaction such as auto-analyze was holding back global xmin.
We can work around that by using a temp table in the test.
Since commit a7212be8b, that will use an up-to-date cutoff xmin
regardless of other processes. And pageinspect itself shouldn't
really care whether the table is temp.
Back-patch to v14. There would be no point in older branches
without back-patching a7212be8b, which seems like more trouble
than the problem is worth.
Discussion: https://postgr.es/m/2892135.1668976646@sss.pgh.pa.us
This switch impacts 9 patterns related to a SQL-mandated special syntax
for function calls:
- LOCALTIME [ ( typmod ) ]
- LOCALTIMESTAMP [ ( typmod ) ]
- CURRENT_TIME [ ( typmod ) ]
- CURRENT_TIMESTAMP [ ( typmod ) ]
- CURRENT_DATE
Five new entries are added to pg_proc to compensate the removal of
SQLValueFunction to provide backward-compatibility and making this
change transparent for the end-user (for example for the attribute
generated when a keyword is specified in a SELECT or in a FROM clause
without an alias, or when specifying something else than an Iconst to
the parser).
The parser included a set of checks coming from the files in charge of
holding the C functions used for the SQLValueFunction calls (as of
transformSQLValueFunction()), which are now moved within each function's
execution path, so this reduces the dependencies between the execution
and the parsing steps. As of this change, all the SQL keywords use the
same paths for their work, relying only on COERCE_SQL_SYNTAX. Like
fb32748, no performance difference has been noticed, while the perf
profiles get reduced with ExecEvalSQLValueFunction() gone.
Bump catalog version.
Reviewed-by: Corey Huinker, Ted Yu
Discussion: https://postgr.es/m/YzaG3MoryCguUOym@paquier.xyz
As per one of the CI reports, there is an assertion failure which
indicates that we were trying to use an unenforced xmin horizon for
decoding snapshots. Though, we couldn't figure out the reason for
assertion failure these checks would help us in finding the reason if the
problem happens again in the future.
Author: Amit Kapila based on suggestions by Andres Freund
Reviewd by: Andres Freund
Discussion: https://postgr.es/m/CAA4eK1L8wYcyTPxNzPGkhuO52WBGoOZbT0A73Le=ZUWYAYmdfw@mail.gmail.com
Until now LWLockDequeueSelf() sequentially searched the list of waiters to see
if the current proc is still is on the list of waiters, or has already been
removed. In extreme workloads, where the wait lists are very long, this leads
to a quadratic behavior. #backends iterating over a list #backends
long. Additionally, the likelihood of needing to call LWLockDequeueSelf() in
the first place also increases with the increased length of the wait queue, as
it becomes more likely that a lock is released while waiting for the wait list
lock, which is held for longer during lock release.
Due to the exponential back-off in perform_spin_delay() this is surprisingly
hard to detect. We should make that easier, e.g. by adding a wait event around
the pg_usleep() - but that's a separate patch.
The fix is simple - track whether a proc is currently waiting in the wait list
or already removed but waiting to be woken up in PGPROC->lwWaiting.
In some workloads with a lot of clients contending for a small number of
lwlocks (e.g. WALWriteLock), the fix can substantially increase throughput.
As the quadratic behavior arguably is a bug, we might want to decide to
backpatch this fix in the future.
Author: Andres Freund <andres@anarazel.de>
Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Discussion: https://postgr.es/m/20221027165914.2hofzp4cvutj6gin@awork3.anarazel.de
Discussion: https://postgr.es/m/CALj2ACXktNbG=K8Xi7PSqbofTZozavhaxjatVc14iYaLu4Maag@mail.gmail.com
As the list of shared relations is fixed, we can just dispatch based
IsSharedRelation(), instead of first trying to look up stats for a non-shared
rel and falling back to shared stats.
Author: "Drouvot, Bertrand" <bertranddrouvot.pg@gmail.com>
Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de
Discussion: https://postgr.es/m/8c1851a2-a98e-e1bc-7729-37b0b95f66ec@gmail.com
Commit 3d14e171e dropped regress_roleoption_donor twice and
regress_roleoption_protagonist not at all. Leaving roles behind
after "make installcheck" is unfriendly in its own right, plus
it causes repeated runs of "make installcheck" to fail.
Commit c94959d41 fixed DROP OPERATOR to reset oprcom/oprnegate links
to the dropped operator; but it missed updating this old comment that
claimed we allow such links to dangle.
Currently there is a race condition where if concurrent TAP tests both
test that they can open a port they will assume that it is free and use
it, causing one of them to fail. To prevent this we record a reservation
using an exclusive lock, and any TAP test that discovers a reservation
checks to see if the reserving process is still alive, and looks for
another free port if it is.
Ports are reserved in a directory set by the environment setting
PG_TEST_PORT_DIR, or if that doesn't exist a subdirectory of the top
build directory as set by meson or Makefile.global, or its own
tmp_check directory.
The prove_check recipe in Makefile.global.in is extended to export
top_builddir to the TAP tests. This was already exported by the
prove_installcheck recipes.
Per complaint from Andres Freund
This will be backpatched in due course after some testing.
Discussion: https://postgr.es/m/20221002164931.d57hlutrcz4d2zi7@awork3.anarazel.de
This commit changes six SQL keywords to use COERCE_SQL_SYNTAX rather
than relying on SQLValueFunction:
- CURRENT_ROLE
- CURRENT_USER
- USER
- SESSION_USER
- CURRENT_CATALOG
- CURRENT_SCHEMA
Among the six, "user", "current_role" and "current_catalog" require
specific SQL functions to allow ruleutils.c to map them to the SQL
keywords these require when using COERCE_SQL_SYNTAX. Having
pg_proc.proname match with the keyword ensures that the compatibility
remains the same when projecting any of these keywords in a FROM clause
to an attribute name when an alias is not specified. This is covered by
the tests added in 2e0d80c, making sure that a correct mapping happens
with each SQL keyword. The three others (current_schema, session_user
and current_user) already have pg_proc entries for this job, so this
brings more consistency between the way such keywords are treated in the
parser, the executor and ruleutils.c.
SQLValueFunction is reduced to half its contents after this change,
simplifying its logic a bit as there is no need to enforce a C collation
anymore for the entries returning a name as a result. I have made a few
performance tests, with a million-ish calls to these keywords without
seeing a difference in run-time or in perf profiles
(ExecEvalSQLValueFunction() is removed from the profiles). The
remaining SQLValueFunctions are now related to timestamps and dates.
Bump catalog version.
Reviewed-by: Corey Huinker
Discussion: https://postgr.es/m/YzaG3MoryCguUOym@paquier.xyz
ProcSleep() used a PGPROC* variable to point to PROC_QUEUE->links.next,
because that does "the right thing" with SHMQueueInsertBefore(). While that
largely works, it's certainly not correct and unnecessary - we can just use
SHM_QUEUE* to point to the insertion point.
Noticed when testing a 32bit of postgres with undefined behavior
sanitizer. UBSan noticed that sometimes the supposed PGPROC wasn't
sufficiently aligned (required since 46d6e5f567, ensured indirectly, via
ShmemAllocRaw() guaranteeing cacheline alignment).
For now fix this by using a SHM_QUEUE* for the insertion point. Subsequently
we should replace all the use of PROC_QUEUE and SHM_QUEUE with ilist.h, but
that's a larger change that we don't want to backpatch.
Backpatch to all supported versions - it's useful to be able to run postgres
under UBSan.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/20221117014230.op5kmgypdv2dtqsf@awork3.anarazel.de
Backpatch: 11-
The test output varies when debug_discard_caches is enabled,
because that causes extra executions of recomputeNamespacePath.
Maybe putting a hook in that was a bad idea, but as a stopgap,
just turn off debug_discard_caches in this test.
Per buildfarm (now that we have debug_discard_caches coverage
again). Back-patch to v15 where this module was added.
Discussion: https://postgr.es/m/2267406.1668804934@sss.pgh.pa.us
basics.source is supposed to be pretty closely in step with
the examples in chapter 2 of the tutorial, but I forgot to
update it in commit f05a5e000. Fix that, and adjust a couple
of other discrepancies that had crept in over time.
(I notice that advanced.source is nowhere near being in sync
with chapter 3, but I lack the ambition to do something
about that right now.)
Similar to how the INHERIT option controls whether or not the
permissions of the granted role are automatically available to the
grantee, the new SET permission controls whether or not the grantee
may use the SET ROLE command to assume the privileges of the granted
role.
In addition, the new SET permission controls whether or not it
is possible to transfer ownership of objects to the target role
or to create new objects owned by the target role using commands
such as CREATE DATABASE .. OWNER. We could alternatively have made
this controlled by the INHERIT option, or allow it when either
option is given. An advantage of this approach is that if you
are granted a predefined role with INHERIT TRUE, SET FALSE, you
can't go and create objects owned by that role.
The underlying theory here is that the ability to create objects
as a target role is not a privilege per se, and thus does not
depend on whether you inherit the target role's privileges. However,
it's surely something you could do anyway if you could SET ROLE
to the target role, and thus making it contingent on whether you
have that ability is reasonable.
Design review by Nathan Bossat, Wolfgang Walther, Jeff Davis,
Peter Eisentraut, and Stephen Frost.
Discussion: http://postgr.es/m/CA+Tgmob+zDSRS6JXYrgq0NWdzCXuTNzT5eK54Dn2hhgt17nm8A@mail.gmail.com
eqjoinsel() currently makes use of MCV stats only when we have such
stats for both sides of the clause. As coded, though, it would
fetch those stats even when they're present for just one side.
This can be a bit expensive with high statistics targets, leading
to wasted effort in common cases such as joining a unique column
to a non-unique column. So it seems worth the trouble to do a quick
pre-check to confirm that both sides have MCVs before fetching either.
Also, tweak the API spec for get_attstatsslot() to document the
method we're using here.
David Geier, Tomas Vondra, Tom Lane
Discussion: https://postgr.es/m/b9846ca0-5f1c-9b26-5881-aad3f42b07f0@gmail.com
The object_address test file turns to psql unaligned output for some
tests to avoid huge diffs for changes. But this is useful also to the
other large test in that file, so apply it there as well. This also
makes verifying the null and whitespace behavior easier.
Version strings with unequal numbers of parts were being compared
incorrectly. We cure this by treating a missing part in the shorter
version as 0.
per complaint from Jehan-Guillaume de Rorthais, but the fix is mine, not
his.
Discussion: https://postgr.es/m/20220628225325.53d97b8d@karst
Backpatch to release 14 where this code was introduced.
This commit improves the handling of the following clauses:
- Addition of "CREATE" for ALTER DEFAULT PRIVILEGES .. GRANT/REVOKE.
- Addition of GRANT|ADMIN|INHERIT OPTION FOR for REVOKE, with some
completion for roles, INHERIT being added recently by e3ce2de.
- Addition of GRANT WITH ADMIN|INHERIT.
The list of privilege options common to GRANT and REVOKE is refactored
to avoid its duplication.
Author: Shi Yu
Reviewed-by: Kyotaro Horiguchi, Michael Paquier, Peter Smith
Discussion: https://postgr.es/m/OSZPR01MB6310FCE8609185A56344EED2FD559@OSZPR01MB6310.jpnprd01.prod.outlook.com
For now the task has been set to be manually triggered, as we are already
limited by the amount of CI time available for windows, particularly on cfbot.
Author: Melih Mutlu <m.melihmutlu@gmail.com>
Reviewed-by: Andrew Dunstan <andrew@dunslane.net>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/CAGPVpCSKS9E0An4=e7ZDnme+y=WOcQFJYJegKO8kE9=gh8NJKQ@mail.gmail.com
Standardize on the name snapshotConflictHorizon for all XID fields from
WAL records that generate recovery conflicts when in hot standby mode.
This supersedes the previous latestRemovedXid naming convention.
The new naming convention places emphasis on how the values are actually
used by REDO routines. How the values are generated during original
execution (details of which vary by record type) is deemphasized. Users
of tools like pg_waldump can now grep for snapshotConflictHorizon to see
all potential sources of recovery conflicts in a standardized way,
without necessarily having to consider which specific record types might
be involved.
Also bring a couple of WAL record types that didn't follow any kind of
naming convention into line. These are heapam's VISIBLE record type and
SP-GiST's VACUUM_REDIRECT record type. Now every WAL record whose REDO
routine calls ResolveRecoveryConflictWithSnapshot() passes through the
snapshotConflictHorizon field from its WAL record. This is follow-up
work to the refactoring from commit 9e540599 that made FREEZE_PAGE WAL
records use a standard snapshotConflictHorizon style XID cutoff.
No bump in XLOG_PAGE_MAGIC, since the underlying format of affected WAL
records doesn't change.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CAH2-Wzm2CQUmViUq7Opgk=McVREHSOorYaAjR1ZpLYkRN7_dPw@mail.gmail.com
Before, receiving a NegotiateProtocolVersion message would result in a
confusing error message like
expected authentication request from server, but received v
This adds proper handling of this protocol message and produces an
on-topic error message from it.
Reviewed-by: Jacob Champion <jchampion@timescale.com>
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/f9c7862f-b864-8ef7-a861-c4638c83e209%40enterprisedb.com
After sending a startup message, libpq expects either an error
response ('E') or an authentication request ('R'). Before processing
the message, it ensures it has read enough bytes to correspond to the
length specified in the message. However, when processing the 'R'
message, if an EOF status is returned it loops back waiting for more
input, even though we already checked that we have enough input. In
this particular case, this is probably not reachable anyway, because
other code ensures we have enough bytes for an authentication request
message, but the code is wrong and misleading. In the more general
case, processing a faulty message could result in an EOF status, which
would then result in an infinite loop waiting for the end of a message
that will never come. The correction is to make this an error.
Reported-by: Jacob Champion <jchampion@timescale.com>
Discussion: https://www.postgresql.org/message-id/flat/f9c7862f-b864-8ef7-a861-c4638c83e209@enterprisedb.com
This commend references a struct that disappeared before MERGE was
merged ... and ExecDelete is not called by the committed MERGE anyway.
Revert to the original wording.
Backpatch to 15
As introduced in 006b69f, the order of the headers was incorrect.
However, it happens that lwlock.h can just be dropped from the list, so
let's be clean and remove it, fixing the order of the listed headers.
Commit 1cc29fe7c, which taught EXPLAIN to print PARAM_EXEC Params as
the referenced expressions, included some checks to prevent matching
Params found in SubPlans or InitPlans to NestLoopParams of upper query
levels. At the time, this seemed possibly necessary to avoid false
matches because of the planner's habit of re-using the same PARAM_EXEC
slot in multiple places in a plan. Furthermore, in the absence of
LATERAL no such reference could be valid anyway. But it's possible
now that we have LATERAL, and in the wake of 46c508fbc and 1db5667ba
I believe the false-match hazard is gone. Hence, remove the
in_same_plan_level checks. As shown in the regression test changes,
this provides a useful improvement in readability for EXPLAIN of
LATERAL-using subplans.
Richard Guo, reviewed by Greg Stark and myself
Discussion: https://postgr.es/m/CAMbWs4-YSOcQXAagJetP95cAeZPqzOy5kM5yijG0PVW5ztRb4w@mail.gmail.com
Commit 05a7be93 changed the timing of the first reply sent by a
walreceiver, which caused a few TAP tests that call wait_for_catchup()
when they haven't actually streamed anything yet to wait ~10 seconds
(wal_receiver_status_interval).
Before commit 05a7be93 the initial reply was sent after 100ms, but
there's no reason not to send it immediately as a slight improvement.
Do the same for HS feedback for consistency.
Author: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/742545.1668377284%40sss.pgh.pa.us
Implement a data structure that is a List of Bitmapsets, which is
essentially a 2-D boolean array except that the rows need not all
be the same width. Operations such as union and intersection are
meaningful for these, just as they are for Bitmapsets. Eventually
we might build many of the same operations that we have written for
Bitmapsets, but for the first use-case we just need a few.
That first use-case is for antijoin detection: reduce_outer_joins
needs to find the set of Vars that are certain to be non-null in a
successfully joined (not null-extended) left join row, and also
find the set of Vars subject to higher-level IS NULL constraints,
and intersect them. We had been doing this by making Lists of
the Var nodes and then using list_intersect, which works but is
pretty inefficient compared to a bitmapset-like intersection.
Potentially it's O(N^2) if there are a lot of Vars involved,
which fortunately there generally aren't; still it's not great.
Moreover, that method requires the Vars of interest to be exactly
equal() in the join condition and the upper IS NULL condition,
which is problematic for my WIP patch that labels Vars according
to which outer joins have possibly nulled them.
Discussion: https://postgr.es/m/892228.1668437838@sss.pgh.pa.us
Discussion: https://postgr.es/m/CAMbWs4-mvPPCJ1W6iK6dD5HiNwoJdi6mZp=-7mE8N9Sh+cd0tQ@mail.gmail.com
We can re-use the clusters set up for this test script's first test,
instead of generating new ones. On my machine this is good for
about a 20% reduction in this script's runtime, from ~6.5 sec to
~5.2 sec.
This idea could be taken further, but it'd require a much more invasive
patch. These cases are easy because the Perl variable names were
already being re-used.
Anton A. Melnikov
Discussion: https://postgr.es/m/eb7aa992-c2d7-6ce7-4942-0c784231a362@inbox.ru
The TAP tests can, to some degree, be controlled by a set of environment
variables. These were however only documented in a README and not in the
main documentation. This adds documentation of these variables, as well
as changes one CPAN reference to a ulink for consistency. While there,
also tag CPAN as an acronym as it's listed in the acronyms section.
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/YyPd9unV14SX2bLF@paquier.xyz
