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2757 commits

Author SHA1 Message Date
Peter Eisentraut
eec0040c4b Add support for NOT ENFORCED in foreign key constraints
This expands the NOT ENFORCED constraint flag, previously only
supported for CHECK constraints (commit ca87c415e2), to foreign key
constraints.

Normally, when a foreign key constraint is created on a table, action
and check triggers are added to maintain data integrity.  With this
patch, if a constraint is marked as NOT ENFORCED, integrity checks are
no longer required, making these triggers unnecessary.  Consequently,
when creating a NOT ENFORCED foreign key constraint, triggers will not
be created, and the constraint will be marked as NOT VALID.
Similarly, if an existing foreign key constraint is changed to NOT
ENFORCED, the associated triggers will be dropped, and the constraint
will also be marked as NOT VALID.  Conversely, if a NOT ENFORCED
foreign key constraint is changed to ENFORCED, the necessary triggers
will be created, and the will be changed to VALID by performing
necessary validation.

Since not-enforced foreign key constraints have no triggers, the
shortcut used for example in psql and pg_dump to skip looking for
foreign keys if the relation is known not to have triggers no longer
applies.  (It already didn't work for partitioned tables.)

Author: Amul Sul <sulamul@gmail.com>
Reviewed-by: Joel Jacobson <joel@compiler.org>
Reviewed-by: Andrew Dunstan <andrew@dunslane.net>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: jian he <jian.universality@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Reviewed-by: Isaac Morland <isaac.morland@gmail.com>
Reviewed-by: Alexandra Wang <alexandra.wang.oss@gmail.com>
Tested-by: Triveni N <triveni.n@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/CAAJ_b962c5AcYW9KUt_R_ER5qs3fUGbe4az-SP-vuwPS-w-AGA@mail.gmail.com
2025-04-02 13:36:44 +02:00
Tom Lane
6c12ae09f5 Introduce a SQL-callable function array_sort(anyarray).
Create a function that will sort the elements of an array
according to the element type's sort order.  If the array
has more than one dimension, the sub-arrays of the first
dimension are sorted per normal array-comparison rules,
leaving their contents alone.

In support of this, add pg_type.typarray to the set of fields
cached by the typcache.

Author: Junwang Zhao <zhjwpku@gmail.com>
Co-authored-by: Jian He <jian.universality@gmail.com>
Reviewed-by: Aleksander Alekseev <aleksander@timescale.com>
Discussion: https://postgr.es/m/CAEG8a3J41a4dpw_-F94fF-JPRXYxw-GfsgoGotKcjs9LVfEEvw@mail.gmail.com
2025-04-01 18:03:55 -04:00
Andres Freund
2a5e709e72 Enable IO concurrency on all systems
Previously effective_io_concurrency and maintenance_io_concurrency could not
be set above 0 on machines without fadvise support. AIO enables IO concurrency
without such support, via io_method=worker.

Currently only subsystems using the read stream API will take advantage of
this. Other users of maintenance_io_concurrency (like recovery prefetching)
which leverage OS advice directly will not benefit from this change. In those
cases, maintenance_io_concurrency will have no effect on I/O behavior.

Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/CAAKRu_atGgZePo=_g6T3cNtfMf0QxpvoUh5OUqa_cnPdhLd=gw@mail.gmail.com
2025-03-30 19:16:47 -04:00
Andres Freund
4244cf6876 Add errhint_internal()
We have errmsg_internal(), errdetail_internal(), but not errhint_internal().

Sometimes it is useful to output a hint with already translated format
string (e.g. because there different messages depending on the condition). For
message/detail we do that with the _internal() variants, but we can't do that
with hint today.  It's possible to work around that that by using something
like
  str = psprintf(translated_format, args);
  ereport(...
          errhint("%s", str);
but that's not exactly pretty and makes it harder to avoid memory leaks.

Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/ym3dqpa4xcvoeknewcw63x77vnqdosbqcetjinb2zfoh65k55m@m4ozmwhr6lk6
2025-03-30 16:10:51 -04:00
Peter Eisentraut
890fc826c9 Use thread-safe strftime_l() instead of strftime().
This removes some setlocale() calls and a lot of commentary about how
dangerous that is.  strftime_l() is from POSIX 2008, and on Windows we
use _wcsftime_l().

While here, adjust error message for strftime_l() failure: it does not
in practice set errno (even though POSIX says it could), so no %m.

Author: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/CA%2BhUKGJqVe0%2BPv9dvC9dSums_PXxGo9SWcxYAMBguWJUGbWz-A%40mail.gmail.com
2025-03-28 07:13:43 +01:00
Michael Paquier
2a0cd38da5 Allow plugins to set a 64-bit plan identifier in PlannedStmt
This field can be optionally set in a PlannedStmt through the planner
hook, giving extensions the possibility to assign an identifier related
to a computed plan.  The backend is changed to report it in the backend
entry of a process running (including the extended query protocol), with
semantics and APIs to set or get it similar to what is used for the
existing query ID (introduced in the backend via 4f0b0966c8).  The plan
ID is reset at the same timing as the query ID.  Currently, this
information is not added to the system view pg_stat_activity; extensions
can access it through PgBackendStatus.

Some patches have been proposed to provide some features in the planning
area, where a plan identifier is used as a key to know the plan involved
(for statistics, plan storage and manipulations, etc.), and the point of
this commit is to provide an anchor in the backend that extensions can
rely on for future work.   The reset of the plan identifier is
controlled by core and follows the same pattern as the query identifier
added in 4f0b0966c8.

The contents of this commit are extracted from a larger set proposed
originally by Lukas Fittl, that Sami Imseih has proposed as an
independent change, with a few tweaks sprinkled by me.

Author: Lukas Fittl <lukas@fittl.com>
Author: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAP53Pkyow59ajFMHGpmb1BK9WHDypaWtUsS_5DoYUEfsa_Hktg@mail.gmail.com
Discussion: https://postgr.es/m/CAA5RZ0vyWd4r35uUBUmhngv8XqeiJUkJDDKkLf5LCoWxv-t_pw@mail.gmail.com
2025-03-24 13:23:42 +09:00
Nathan Bossart
0164a0f9ee Add vacuum_truncate configuration parameter.
This new parameter works just like the storage parameter of the
same name: if set to true (which is the default), autovacuum and
VACUUM attempt to truncate any empty pages at the end of the table.
It is primarily intended to help users avoid locking issues on hot
standbys.  The setting can be overridden with the storage parameter
or VACUUM's TRUNCATE option.

Since there's presently no way to determine whether a Boolean
storage parameter is explicitly set or has just picked up the
default value, this commit also introduces an isset_offset member
to relopt_parse_elt.

Suggested-by: Will Storey <will@summercat.com>
Author: Nathan Bossart <nathandbossart@gmail.com>
Co-authored-by: Gurjeet Singh <gurjeet@singh.im>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Robert Treat <rob@xzilla.net>
Discussion: https://postgr.es/m/Z2DE4lDX4tHqNGZt%40dev.null
2025-03-20 10:16:50 -05:00
Thomas Munro
10f6646847 Introduce io_max_combine_limit.
The existing io_combine_limit can be changed by users.  The new
io_max_combine_limit is fixed at server startup time, and functions as a
silent clamp on the user setting.  That in itself is probably quite
useful, but the primary motivation is:

aio_init.c allocates shared memory for all asynchronous IOs including
some per-block data, and we didn't want to waste memory you'd never used
by assuming they could be up to PG_IOV_MAX.  This commit already halves
the size of 'AioHandleIov' and 'AioHandleData'.  A follow-up commit can
now expand PG_IOV_MAX without affecting that.

Since our GUC system doesn't support dependencies or cross-checks
between GUCs, the user-settable one now assigns a "raw" value to
io_combine_limit_guc, and the lower of io_combine_limit_guc and
io_max_combine_limit is maintained in io_combine_limit.

Reviewed-by: Andres Freund <andres@anarazel.de> (earlier version)
Discussion: https://postgr.es/m/CA%2BhUKG%2B2T9p-%2BzM6Eeou-RAJjTML6eit1qn26f9twznX59qtCA%40mail.gmail.com
2025-03-19 15:23:54 +13:00
Peter Eisentraut
7317e64126 Add some opfamily support functions to lsyscache.c
Add get_opfamily_method() and get_opfamily_member_for_cmptype() in
lsyscache.c.  No callers yet, but we'll add some soon.  This is part
of generalizing some parts of the code away from having btree
hardcoded and use CompareType instead.

Author: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
2025-03-18 11:17:43 +01:00
Andres Freund
02844012b3 aio: Basic subsystem initialization
This commit just does the minimal wiring up of the AIO subsystem, added in the
next commit, to the rest of the system. The next commit contains more details
about motivation and architecture.

This commit is kept separate to make it easier to review, separating the
changes across the tree, from the implementation of the new subsystem.

We discussed squashing this commit with the main commit before merging AIO,
but there has been a mild preference for keeping it separate.

Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
2025-03-17 18:51:33 -04:00
Tom Lane
1c9242b2cd Doc: remove obsolete comment.
This para should have been removed by 2f9661311, which made it
both false and irrelevant.  Noted while looking at SQL function
plancache patch.
2025-03-14 14:08:47 -04:00
Peter Eisentraut
a359d37019 Simplify and generalize PrepareSortSupportFromIndexRel()
PrepareSortSupportFromIndexRel() was accepting btree strategy numbers
purely for the purpose of comparing it later against btree strategies
to determine if the sort direction was forward or reverse.  Change
that.  Instead, pass a bool directly, to indicate the same without an
unfortunate assumption that a strategy number refers specifically to a
btree strategy.  (This is similar in spirit to commits 0d2aa4d493 and
c594f1ad2ba.)

(This could arguably be simplfied further by having the callers fill
in ssup_reverse directly.  But this way, it preserves consistency by
having all PrepareSortSupport*() variants be responsible for filling
in ssup_reverse.)

Moreover, remove the hardcoded check against BTREE_AM_OID, and check
against amcanorder instead, which is the actual requirement.

Co-authored-by: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
2025-03-14 10:34:08 +01:00
Peter Eisentraut
05cbd6cb22 Swap order of extern/static and pg_nodiscard
When pg_nodiscard was first added, the C standard draft had it as a
function specifier, and so the code comment about placement was
written with that in mind.  The final C23 standard has it as an
attribute and the placement rules are a bit different for that.
Specifically, it needs to be before extern or static.  (Or at least
both current clang and gcc require that.)  So just swap these.  (To be
clear: The current implementation with gcc attributes doesn't care.
This change is just for maximum forward compatibility for non-gcc
compilers.)  This also keeps the order consistent with the previously
introduced pg_noreturn.  Also update the code comment to reflect the
mentioned developments since its introduction.

Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/flat/pxr5b3z7jmkpenssra5zroxi7qzzp6eswuggokw64axmdixpnk@zbwxuq7gbbcw
2025-03-14 07:18:07 +01:00
Peter Eisentraut
3691edfab9 pg_noreturn to replace pg_attribute_noreturn()
We want to support a "noreturn" decoration on more compilers besides
just GCC-compatible ones, but for that we need to move the decoration
in front of the function declaration instead of either behind it or
wherever, which is the current style afforded by GCC-style attributes.
Also rename the macro to "pg_noreturn" to be similar to the C11
standard "noreturn".

pg_noreturn is now supported on all compilers that support C11 (using
_Noreturn), as well as GCC-compatible ones (using __attribute__, as
before), as well as MSVC (using __declspec).  (When PostgreSQL
requires C11, the latter two variants can be dropped.)

Now, all supported compilers effectively support pg_noreturn, so the
extra code for !HAVE_PG_ATTRIBUTE_NORETURN can be dropped.

This also fixes a possible problem if third-party code includes
stdnoreturn.h, because then the current definition of

    #define pg_attribute_noreturn() __attribute__((noreturn))

would cause an error.

Note that the C standard does not support a noreturn attribute on
function pointer types.  So we have to drop these here.  There are
only two instances at this time, so it's not a big loss.  In one case,
we can make up for it by adding the pg_noreturn to a wrapper function
and adding a pg_unreachable(), in the other case, the latter was
already done before.

Reviewed-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/flat/pxr5b3z7jmkpenssra5zroxi7qzzp6eswuggokw64axmdixpnk@zbwxuq7gbbcw
2025-03-13 12:37:26 +01:00
Amit Kapila
3abe9dc188 Avoid invalidating all RelationSyncCache entries on publication rename.
On Publication rename, we need to only invalidate the RelationSyncCache
entries corresponding to relations that are part of the publication being
renamed.

As part of this patch, we introduce a new invalidation message to
invalidate the cache maintained by the logical decoding output plugin. We
can't use existing relcache invalidation for this purpose, as that would
unnecessarily cause relcache invalidations in other backends.

This will improve performance by building fewer relation cache entries
during logical replication.

Author: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Author: Shlok Kyal <shlok.kyal.oss@gmail.com>
Reviewed-by: Hou Zhijie <houzj.fnst@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/OSCPR01MB14966C09AA201EFFA706576A7F5C92@OSCPR01MB14966.jpnprd01.prod.outlook.com
2025-03-13 09:16:33 +05:30
Melanie Plageman
18cd15e706 Add connection establishment duration logging
Add log_connections option 'setup_durations' which logs durations of
several key parts of connection establishment and backend setup.

For an incoming connection, starting from when the postmaster gets a
socket from accept() and ending when the forked child backend is first
ready for query, there are multiple steps that could each take longer
than expected due to external factors. This logging provides visibility
into authentication and fork duration as well as the end-to-end
connection establishment and backend initialization time.

To make this portable, the timings captured in the postmaster (socket
creation time, fork initiation time) are passed through the
BackendStartupData.

Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Jacob Champion <jacob.champion@enterprisedb.com>
Reviewed-by: Jelte Fennema-Nio <postgres@jeltef.nl>
Reviewed-by: Guillaume Lelarge <guillaume.lelarge@dalibo.com>
Discussion: https://postgr.es/m/flat/CAAKRu_b_smAHK0ZjrnL5GRxnAVWujEXQWpLXYzGbmpcZd3nLYw%40mail.gmail.com
2025-03-12 11:35:27 -04:00
Melanie Plageman
9219093cab Modularize log_connections output
Convert the boolean log_connections GUC into a list GUC comprised of the
connection aspects to log.

This gives users more control over the volume and kind of connection
logging.

The current log_connections options are 'receipt', 'authentication', and
'authorization'. The empty string disables all connection logging. 'all'
enables all available connection logging.

For backwards compatibility, the most common values for the
log_connections boolean are still supported (on, off, 1, 0, true, false,
yes, no). Note that previously supported substrings of on, off, true,
false, yes, and no are no longer supported.

Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/flat/CAAKRu_b_smAHK0ZjrnL5GRxnAVWujEXQWpLXYzGbmpcZd3nLYw%40mail.gmail.com
2025-03-12 11:35:21 -04:00
Tom Lane
8b1b342544 Improve EXPLAIN's display of window functions.
Up to now we just punted on showing the window definitions used
in a plan, with window function calls represented as "OVER (?)".
To improve that, show the window definition implemented by each
WindowAgg plan node, and reference their window names in OVER.
For nameless window clauses generated by "OVER (...)", assign
unique names w1, w2, etc.

In passing, re-order the properties shown for a WindowAgg node
so that the Run Condition (if any) appears after the Window
property and before the Filter (if any).  This seems more
sensible since the Run Condition is associated with the Window
and acts before the Filter.

Thanks to David G. Johnston and Álvaro Herrera for design
suggestions.

Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/144530.1741469955@sss.pgh.pa.us
2025-03-11 11:19:54 -04:00
Michael Paquier
76def4cdd7 Add WAL data to backend statistics
This commit adds per-backend WAL statistics, providing the same
information as pg_stat_wal, except that it is now possible to know how
much WAL activity is happening in each backend rather than an overall
aggregate of all the activity.  Like pg_stat_wal, the implementation
relies on pgWalUsage, tracking the difference of activity between two
reports to pgstats.

This data can be retrieved with a new system function called
pg_stat_get_backend_wal(), that returns one tuple based on the PID
provided in input.  Like pg_stat_get_backend_io(), this is useful when
joined with pg_stat_activity to get a live picture of the WAL generated
for each running backend, showing how the activity is [un]balanced.

pgstat_flush_backend() gains a new flag value, able to control the flush
of the WAL stats.

This commit relies mostly on the infrastructure provided by
9aea73fc61, that has introduced backend statistics.

Bump catalog version.  A bump of PGSTAT_FILE_FORMAT_ID is not required,
as backend stats do not persist on disk.

Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reviewed-by: Xuneng Zhou <xunengzhou@gmail.com>
Discussion: https://postgr.es/m/Z3zqc4o09dM/Ezyz@ip-10-97-1-34.eu-west-3.compute.internal
2025-03-11 09:04:11 +09:00
Alexander Korotkov
6bb6a62f3c Use extended stats for precise estimation of bucket size in hash join
Recognizing the real-life complexity where columns in the table often have
functional dependencies, PostgreSQL's estimation of the number of distinct
values over a set of columns can be underestimated (or much rarely,
overestimated) when dealing with multi-clause JOIN.  In the case of hash
join, it can end up with a small number of predicted hash  buckets and, as
a result, picking non-optimal merge join.

To improve the situation, we introduce one additional stage of bucket size
estimation - having two or more join clauses estimator lookup for extended
statistics and use it for multicolumn estimation.  Clauses are grouped into
lists, each containing expressions referencing the same relation.  The result
of the multicolumn estimation made over such a list is combined with others
according to the caller's logic.  Clauses that are not estimated are returned
to the caller for further estimation.

Discussion: https://postgr.es/m/52257607-57f6-850d-399a-ec33a654457b%40postgrespro.ru
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Andy Fan <zhihui.fan1213@gmail.com>
Reviewed-by: Tomas Vondra <tomas.vondra@enterprisedb.com>
Reviewed-by: Alena Rybakina <lena.ribackina@yandex.ru>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
2025-03-10 13:42:01 +02:00
Michael Paquier
c76db55c90 Split pgstat_bestart() into three different routines
pgstat_bestart(), used post-authentication to set up a backend entry
in the PgBackendStatus array, so as its data becomes visible in
pg_stat_activity and related catalogs, has its logic divided into three
routines with this commit, called in order at different steps of the
backend initialization:
* pgstat_bestart_initial() sets up the backend entry with a minimal
amount of information, reporting it with a new BackendState called
STATE_STARTING while waiting for backend initialization and client
authentication to complete.  The main benefit that this offers is
observability, so as it is possible to monitor the backend activity
during authentication.  This step happens earlier than in the logic
prior to this commit.  pgstat_beinit() happens earlier as well, before
authentication.
* pgstat_bestart_security() reports the SSL/GSS status of the
connection, once authentication completes.  Auxiliary processes, for
example, do not need to call this step, hence it is optional.  This
step is called after performing authentication, same as previously.
* pgstat_bestart_final() reports the user and database IDs, takes the
entry out of STATE_STARTING, and reports its application_name.  This is
called as the last step of the three, once authentication completes.

An injection point is added, with a test checking that the "starting"
phase of a backend entry is visible in pg_stat_activity.  Some follow-up
patches are planned to take advantage of this refactoring with more
information provided in backend entries during authentication (LDAP
hanging was a problem for the author, initially).

Author: Jacob Champion <jacob.champion@enterprisedb.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CAOYmi+=60deN20WDyCoHCiecgivJxr=98s7s7-C8SkXwrCfHXg@mail.gmail.com
2025-03-04 14:09:44 +09:00
Tomas Vondra
8492feb98f Allow parallel CREATE INDEX for GIN indexes
Allow using parallel workers to build a GIN index, similarly to BTREE
and BRIN. For large tables this may result in significant speedup when
the build is CPU-bound.

The work is divided so that each worker builds index entries on a subset
of the table, determined by the regular parallel scan used to read the
data. Each worker uses a local tuplesort to sort and merge the entries
for the same key. The TID lists do not overlap (for a given key), which
means the merge sort simply concatenates the two lists. The merged
entries are written into a shared tuplesort for the leader.

The leader needs to merge the sorted entries again, before writing them
into the index. But this way a significant part of the work happens in
the workers, and the leader is left with merging fewer large entries,
which is more efficient.

Most of the parallelism infrastructure is a simplified copy of the code
used by BTREE indexes, omitting the parts irrelevant for GIN indexes
(e.g. uniqueness checks).

Original patch by me, with reviews and substantial improvements by
Matthias van de Meent, certainly enough to make him a co-author.

Author: Tomas Vondra, Matthias van de Meent
Reviewed-by: Matthias van de Meent, Andy Fan, Kirill Reshke
Discussion: https://postgr.es/m/6ab4003f-a8b8-4d75-a67f-f25ad98582dc%40enterprisedb.com
2025-03-03 16:53:06 +01:00
Michael Paquier
d7cbeaf261 Remove pgstat_flush_wal()
All the processes that generate WAL should call pgstat_report_wal() to
report all their statistics related to WAL, and this is already what
happens in the tree.  Keeping pgstat_report_wal() is confusing while the
other routine is encouraged.

This routine is not required since fc415edf8c, where it was lastly
used in pgstat_report_stat() before an equivalent callback existed.

Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/Z71oPkJJICrRB5Ws@paquier.xyz
2025-02-26 15:37:28 +09:00
Amit Langote
525392d572 Don't lock partitions pruned by initial pruning
Before executing a cached generic plan, AcquireExecutorLocks() in
plancache.c locks all relations in a plan's range table to ensure the
plan is safe for execution. However, this locks runtime-prunable
relations that will later be pruned during "initial" runtime pruning,
introducing unnecessary overhead.

This commit defers locking for such relations to executor startup and
ensures that if the CachedPlan is invalidated due to concurrent DDL
during this window, replanning is triggered. Deferring these locks
avoids unnecessary locking overhead for pruned partitions, resulting
in significant speedup, particularly when many partitions are pruned
during initial runtime pruning.

* Changes to locking when executing generic plans:

AcquireExecutorLocks() now locks only unprunable relations, that is,
those found in PlannedStmt.unprunableRelids (introduced in commit
cbc127917e), to avoid locking runtime-prunable partitions
unnecessarily.  The remaining locks are taken by
ExecDoInitialPruning(), which acquires them only for partitions that
survive pruning.

This deferral does not affect the locks required for permission
checking in InitPlan(), which takes place before initial pruning.
ExecCheckPermissions() now includes an Assert to verify that all
relations undergoing permission checks, none of which can be in the
set of runtime-prunable relations, are properly locked.

* Plan invalidation handling:

Deferring locks introduces a window where prunable relations may be
altered by concurrent DDL, invalidating the plan. A new function,
ExecutorStartCachedPlan(), wraps ExecutorStart() to detect and handle
invalidation caused by deferred locking. If invalidation occurs,
ExecutorStartCachedPlan() updates CachedPlan using the new
UpdateCachedPlan() function and retries execution with the updated
plan. To ensure all code paths that may be affected by this handle
invalidation properly, all callers of ExecutorStart that may execute a
PlannedStmt from a CachedPlan have been updated to use
ExecutorStartCachedPlan() instead.

UpdateCachedPlan() replaces stale plans in CachedPlan.stmt_list. A new
CachedPlan.stmt_context, created as a child of CachedPlan.context,
allows freeing old PlannedStmts while preserving the CachedPlan
structure and its statement list. This ensures that loops over
statements in upstream callers of ExecutorStartCachedPlan() remain
intact.

ExecutorStart() and ExecutorStart_hook implementations now return a
boolean value indicating whether plan initialization succeeded with a
valid PlanState tree in QueryDesc.planstate, or false otherwise, in
which case QueryDesc.planstate is NULL. Hook implementations are
required to call standard_ExecutorStart() at the beginning, and if it
returns false, they should do the same without proceeding.

* Testing:

To verify these changes, the delay_execution module tests scenarios
where cached plans become invalid due to changes in prunable relations
after deferred locks.

* Note to extension authors:

ExecutorStart_hook implementations must verify plan validity after
calling standard_ExecutorStart(), as explained earlier. For example:

    if (prev_ExecutorStart)
        plan_valid = prev_ExecutorStart(queryDesc, eflags);
    else
        plan_valid = standard_ExecutorStart(queryDesc, eflags);

    if (!plan_valid)
        return false;

    <extension-code>

    return true;

Extensions accessing child relations, especially prunable partitions,
via ExecGetRangeTableRelation() must now ensure their RT indexes are
present in es_unpruned_relids (introduced in commit cbc127917e), or
they will encounter an error. This is a strict requirement after this
change, as only relations in that set are locked.

The idea of deferring some locks to executor startup, allowing locks
for prunable partitions to be skipped, was first proposed by Tom Lane.

Reviewed-by: Robert Haas <robertmhaas@gmail.com> (earlier versions)
Reviewed-by: David Rowley <dgrowleyml@gmail.com> (earlier versions)
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> (earlier versions)
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Reviewed-by: Junwang Zhao <zhjwpku@gmail.com>
Discussion: https://postgr.es/m/CA+HiwqFGkMSge6TgC9KQzde0ohpAycLQuV7ooitEEpbKB0O_mg@mail.gmail.com
2025-02-20 17:09:48 +09:00
Alexander Korotkov
e983ee9380 Improve statistics estimation for single-column GROUP BY in sub-queries
This commit follows the idea of the 4767bc8ff2.  If sub-query has only one
GROUP BY column, we can consider its output variable as being unique. We can
employ this fact in the statistics to make more precise estimations in the
upper query block.

Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
2025-02-19 11:59:30 +02:00
Amit Kapila
ac0e33136a Invalidate inactive replication slots.
This commit introduces idle_replication_slot_timeout GUC that allows
inactive slots to be invalidated at the time of checkpoint. Because
checkpoints happen checkpoint_timeout intervals, there can be some lag
between when the idle_replication_slot_timeout was exceeded and when the
slot invalidation is triggered at the next checkpoint. To avoid such lags,
users can force a checkpoint to promptly invalidate inactive slots.

Note that the idle timeout invalidation mechanism is not applicable for
slots that do not reserve WAL or for slots on the standby server that are
synced from the primary server (i.e., standby slots having 'synced' field
'true'). Synced slots are always considered to be inactive because they
don't perform logical decoding to produce changes.

The slots can become inactive for a long period if a subscriber is down
due to a system error or inaccessible because of network issues. If such a
situation persists, it might be more practical to recreate the subscriber
rather than attempt to recover the node and wait for it to catch up which
could be time-consuming.

Then, external tools could create replication slots (e.g., for migrations
or upgrades) that may fail to remove them if an error occurs, leaving
behind unused slots that take up space and resources. Manually cleaning
them up can be tedious and error-prone, and without intervention, these
lingering slots can cause unnecessary WAL retention and system bloat.

As the duration of idle_replication_slot_timeout is in minutes, any test
using that would be time-consuming. We are planning to commit a follow up
patch for tests by using the injection point framework.

Author: Nisha Moond <nisha.moond412@gmail.com>
Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Hou Zhijie <houzj.fnst@fujitsu.com>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/CALj2ACW4aUe-_uFQOjdWCEN-xXoLGhmvRFnL8SNw_TZ5nJe+aw@mail.gmail.com
Discussion: https://postgr.es/m/OS0PR01MB5716C131A7D80DAE8CB9E88794FC2@OS0PR01MB5716.jpnprd01.prod.outlook.com
2025-02-19 09:29:50 +05:30
Daniel Gustafsson
95ef3d9029 Add PGErrorVerbosity to typedefs.list
PGErrorVerbosity was missing which resulted in incorrect whitespace
alignment going back all the way to e3860ffa4d.  No backpatch for
this though since we don't pgindent backbranches.

Author: Jelte Fennema-Nio <postgres@jeltef.nl>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/CAGECzQTVi8n-HW4Q27je-b9ckQk7zf6bS_it42gNvQu+DX0NCQ@mail.gmail.com
2025-02-18 13:23:13 +01:00
Nathan Bossart
977d865c36 Describe special values in GUC descriptions more consistently.
Many GUCs accept special values like -1 or an empty string to
disable the feature, use a system default, etc.  While the
documentation consistently lists these special values, the GUC
descriptions do not.  Many such descriptions fail to mention the
special values, and those that do vary in phrasing and placement.
This commit aims to bring some consistency to this area by applying
the following rules:

* Special values should be listed at the end of the long
  description.
* Descriptions should use numerals (e.g., "0") instead of words
  (e.g., "zero").
* Special value mentions should be concise and direct (e.g., "0
  disables the timeout.", "An empty string means use the operating
  system setting.").
* Multiple special values should be listed in ascending order.

Of course, there are exceptions, such as
max_pred_locks_per_relation and search_path, whose special values
are too complex to include.  And there are cases like
listen_addresses, where the meaning of an empty string is arguably
too obvious to include.  In those cases, I've refrained from adding
special value information to the GUC description.

Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: "David G. Johnston" <david.g.johnston@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/Z6aIy4aywxUZHAo6%40nathan
2025-02-14 10:44:30 -06:00
Melanie Plageman
052026c9b9 Eagerly scan all-visible pages to amortize aggressive vacuum
Aggressive vacuums must scan every unfrozen tuple in order to advance
the relfrozenxid/relminmxid. Because data is often vacuumed before it is
old enough to require freezing, relations may build up a large backlog
of pages that are set all-visible but not all-frozen in the visibility
map. When an aggressive vacuum is triggered, all of these pages must be
scanned. These pages have often been evicted from shared buffers and
even from the kernel buffer cache. Thus, aggressive vacuums often incur
large amounts of extra I/O at the expense of foreground workloads.

To amortize the cost of aggressive vacuums, eagerly scan some
all-visible but not all-frozen pages during normal vacuums.

All-visible pages that are eagerly scanned and set all-frozen in the
visibility map are counted as successful eager freezes and those not
frozen are counted as failed eager freezes.

If too many eager scans fail in a row, eager scanning is temporarily
suspended until a later portion of the relation. The number of failures
tolerated is configurable globally and per table.

To effectively amortize aggressive vacuums, we cap the number of
successes as well. Capping eager freeze successes also limits the amount
of potentially wasted work if these pages are modified again before the
next aggressive vacuum. Once we reach the maximum number of blocks
successfully eager frozen, eager scanning is disabled for the remainder
of the vacuum of the relation.

Original design idea from Robert Haas, with enhancements from
Andres Freund, Tomas Vondra, and me

Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Robert Treat <rob@xzilla.net>
Reviewed-by: Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/flat/CAAKRu_ZF_KCzZuOrPrOqjGVe8iRVWEAJSpzMgRQs%3D5-v84cXUg%40mail.gmail.com
2025-02-11 13:53:48 -05:00
Andres Freund
4dd09a1d41 config: Rename "Asynchronous Behavior" to "I/O"
"I/O" seems more descriptive than "Asynchronous Behavior", given that some of
the GUCs in the section don't relate to anything asynchronous.

Most other abbreviations in the config sections are un-abbreviated, but
"Input/Output" seems less likely to be helpful than just IO or I/O.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/x3tlw2jk5gm3r3mv47hwrshffyw7halpczkfbk3peksxds7bvc@lguk43z3bsyq
2025-02-11 12:53:40 -05:00
Andres Freund
740766d37c config: Split "Worker Processes" out of "Asynchronous Behavior"
Having all the worker related GUCs in the same section as IO controlling GUCs
doesn't really make sense. Create a separate section for them.

Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/x3tlw2jk5gm3r3mv47hwrshffyw7halpczkfbk3peksxds7bvc@lguk43z3bsyq
2025-02-11 12:53:40 -05:00
Nathan Bossart
306dc520b9 Introduce autovacuum_vacuum_max_threshold.
One way autovacuum chooses tables to vacuum is by comparing the
number of updated or deleted tuples with a value calculated using
autovacuum_vacuum_threshold and autovacuum_vacuum_scale_factor.
The threshold specifies the base value for comparison, and the
scale factor specifies the fraction of the table size to add to it.
This strategy ensures that smaller tables are vacuumed after fewer
updates/deletes than larger tables, which is reasonable in many
cases but can result in infrequent vacuums on very large tables.
This is undesirable for a couple of reasons, such as very large
tables incurring a huge amount of bloat between vacuums.

This new parameter provides a way to set a limit on the value
calculated with autovacuum_vacuum_threshold and
autovacuum_vacuum_scale_factor so that very large tables are
vacuumed more frequently.  By default, it is set to 100,000,000
tuples, but it can be disabled by setting it to -1.  It can also be
adjusted for individual tables by changing storage parameters.

Author: Nathan Bossart <nathandbossart@gmail.com>
Co-authored-by: Frédéric Yhuel <frederic.yhuel@dalibo.com>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: Michael Banck <mbanck@gmx.net>
Reviewed-by: Joe Conway <mail@joeconway.com>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: wenhui qiu <qiuwenhuifx@gmail.com>
Reviewed-by: Vinícius Abrahão <vinnix.bsd@gmail.com>
Reviewed-by: Robert Treat <rob@xzilla.net>
Reviewed-by: Alena Rybakina <a.rybakina@postgrespro.ru>
Discussion: https://postgr.es/m/956435f8-3b2f-47a6-8756-8c54ded61802%40dalibo.com
2025-02-05 15:48:18 -06:00
Peter Eisentraut
43493cceda Add get_opfamily_name() function
This refactors and simplifies various existing code to make use of the
new function.

Reviewed-by: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
2025-02-01 10:42:58 +01:00
Tom Lane
041e8b95b8 Get rid of our dependency on type "long" for memory size calculations.
Consistently use "Size" (or size_t, or in some places int64 or double)
as the type for variables holding memory allocation sizes.  In most
places variables' data types were fine already, but we had an ancient
habit of computing bytes from kilobytes-units GUCs with code like
"work_mem * 1024L".  That risks overflow on Win64 where they did not
make "long" as wide as "size_t".  We worked around that by restricting
such GUCs' ranges, so you couldn't set work_mem et al higher than 2GB
on Win64.  This patch removes that restriction, after replacing such
calculations with "work_mem * (Size) 1024" or variants of that.

It should be noted that this patch was constructed by searching
outwards from the GUCs that have MAX_KILOBYTES as upper limit.
So I can't positively guarantee there are no other places doing
memory-size arithmetic in int or long variables.  I do however feel
pretty confident that increasing MAX_KILOBYTES on Win64 is safe now.
Also, nothing in our code should be dealing in multiple-gigabyte
allocations without authorization from a relevant GUC, so it seems
pretty likely that this search caught everything that could be at
risk of overflow.

Author: Vladlen Popolitov <v.popolitov@postgrespro.ru>
Co-authored-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/1a01f0-66ec2d80-3b-68487680@27595217
2025-01-31 13:52:40 -05:00
Michael Paquier
ce5c620fb6 Add pgstat_drop_matching_entries() to pgstats
This allows users of the cumulative statistics to drop entries in the
shared hash stats table, deleting as well local references.  Callers of
this function can optionally define a callback able to filter which
entries to drop, similarly to pgstat_reset_matching_entries() with its
callback do_reset().

pgstat_drop_all_entries() is refactored so as it uses this new function.

Author: Lukas Fitti
Discussion: https://postgr.es/m/CAP53PkwuFbo3NkwZgxwNRMjMfqPEqidD-SggaoQ4ijotBVLJAA@mail.gmail.com
2025-01-31 12:27:19 +09:00
Jeff Davis
bfc5992069 Add SQL function CASEFOLD().
Useful for caseless matching. Similar to LOWER(), but avoids edge-case
problems with using LOWER() for caseless matching.

For collations that support it, CASEFOLD() handles characters with
more than two case variations or multi-character case variations. Some
characters may fold to uppercase. The results of case folding are also
more stable across Unicode versions than LOWER() or UPPER().

Discussion: https://postgr.es/m/a1886ddfcd8f60cb3e905c93009b646b4cfb74c5.camel%40j-davis.com
Reviewed-by: Ian Lawrence Barwick
2025-01-24 14:56:22 -08:00
Michael Paquier
4feba03d8b Rework handling of pending data for backend statistics
9aea73fc61 has added support for backend statistics, relying on
PgStat_EntryRef->pending for its data pending for flush.  This design
lacks in flexibility, because the pending list does some memory
allocation, making it unsuitable if incrementing counters in critical
sections.

Pending data of backend statistics is reworked so the implementation
does not depend on PgStat_EntryRef->pending anymore, relying on a static
area of memory to store the counters that are flushed when stats are
reported to the pgstats dshash.  An advantage of this approach is to
allow the pending data to be manipulated in critical sections; some
patches are under discussion and require that.

The pending data is tracked by PendingBackendStats, local to
pgstat_backend.c.  Two routines are introduced to allow IO statistics to
update the backend-side counters.  have_static_pending_cb and
flush_static_cb are used for the flush, instead of flush_pending_cb.

Author: Bertrand Drouvot, Michael Paquier
Discussion: https://postgr.es/m/66efowskppsns35v5u2m7k4sdnl7yoz5bo64tdjwq7r5lhplrz@y7dme5xwh2r5
2025-01-21 11:30:42 +09:00
Michael Paquier
28de66cee5 Rename some pgstats callbacks related to flush of entries
The two callbacks have_fixed_pending_cb and flush_fixed_cb have been
introduced in fc415edf8c to provide a way for fixed-numbered
statistics to control the flush of their data.  These are renamed to
respectively have_static_pending_cb and flush_static_cb.  The
restriction that these only apply to fixed-numbered stats is removed.

A follow-up patch will make use of them for backend statistics.  This
stats kind is variable-numbered, and patches are under discussion to
track WAL data for IO and backend stats which cannot use
PgStat_EntryRef->pending as pending data would be touched in critical
sections, where no memory allocation can happen.

Per discussion with Andres Freund.

Author: Bertrand Drouvot
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/66efowskppsns35v5u2m7k4sdnl7yoz5bo64tdjwq7r5lhplrz@y7dme5xwh2r5
2025-01-21 10:12:39 +09:00
Jeff Davis
d3d0983169 Support PG_UNICODE_FAST locale in the builtin collation provider.
The PG_UNICODE_FAST locale uses code point sort order (fast,
memcmp-based) combined with Unicode character semantics. The character
semantics are based on Unicode full case mapping.

Full case mapping can map a single codepoint to multiple codepoints,
such as "ß" uppercasing to "SS". Additionally, it handles
context-sensitive mappings like the "final sigma", and it uses
titlecase mappings such as "Dž" when titlecasing (rather than plain
uppercase mappings).

Importantly, the uppercasing of "ß" as "SS" is specifically mentioned
by the SQL standard. In Postgres, UCS_BASIC uses plain ASCII semantics
for case mapping and pattern matching, so if we changed it to use the
PG_UNICODE_FAST locale, it would offer better compliance with the
standard. For now, though, do not change the behavior of UCS_BASIC.

Discussion: https://postgr.es/m/ddfd67928818f138f51635712529bc5e1d25e4e7.camel@j-davis.com
Discussion: https://postgr.es/m/27bb0e52-801d-4f73-a0a4-02cfdd4a9ada@eisentraut.org
Reviewed-by: Peter Eisentraut, Daniel Verite
2025-01-17 15:56:30 -08:00
Tom Lane
d7674c9fab Seek zone abbreviations in the IANA data before timezone_abbreviations.
If a time zone abbreviation used in datetime input is defined in
the currently active timezone, use that definition in preference
to looking in the timezone_abbreviations list.  That allows us to
correctly handle abbreviations that have different meanings in
different timezones.  Also, it eliminates an inconsistency between
datetime input and datetime output: the non-ISO datestyles for
timestamptz have always printed abbreviations taken from the IANA
data, not from timezone_abbreviations.  Before this fix, it was
possible to demonstrate cases where casting a timestamp to text
and back fails or changes the value significantly because of that
inconsistency.

While this change removes the ability to override the IANA data about
an abbreviation known in the current zone, it's not clear that there's
any real use-case for doing so.  But it is clear that this makes life
a lot easier for dealing with abbreviations that have conflicts across
different time zones.

Also update the pg_timezone_abbrevs view to report abbreviations
that are recognized via the IANA data, and *not* report any
timezone_abbreviations entries that are thereby overridden.
Under the hood, there are now two SRFs, one that pulls the IANA
data and one that pulls timezone_abbreviations entries.  They're
combined by logic in the view.  This approach was useful for
debugging (since the functions can be called on their own).
While I don't intend to document the functions explicitly,
they might be useful to call directly.

Also improve DecodeTimezoneAbbrev's caching logic so that it can
cache zone abbreviations found in the IANA data.  Without that,
this patch would have caused a noticeable degradation of the
runtime of timestamptz_in.

Per report from Aleksander Alekseev and additional investigation.

Discussion: https://postgr.es/m/CAJ7c6TOATjJqvhnYsui0=CO5XFMF4dvTGH+skzB--jNhqSQu5g@mail.gmail.com
2025-01-16 14:11:19 -05:00
Peter Eisentraut
74938d1320 IWYU widely useful pragmas
Add various widely useful "IWYU pragma" annotations, such as

- Common header files such as c.h, postgres.h should be "always_keep".

- System headers included in c.h, postgres.h etc. should be considered
  "export".

- Some portability headers such as getopt_long.h should be
  "always_keep", so they are not considered superfluous on some
  platforms.

- Certain system headers included from portability headers should be
  considered "export" because the purpose of the portability header is
  to wrap them.

- Superfluous includes marked as "for backward compatibility" get a
  formal IWYU annotation.

- Generated header included in utils/syscache.h is marked exported.
  This is a very commonly used include and this avoids lots of
  complaints.

Discussion: https://www.postgresql.org/message-id/flat/9395d484-eff4-47c2-b276-8e228526c8ae@eisentraut.org
2025-01-15 18:57:53 +01:00
Melanie Plageman
2ae98ea5ab Synchronize guc_tables.c categories with vacuum docs categories
ca9c6a5680 consolidated most of the vacuum-related GUCs' documentation
into a new subsection. af2317652d then enforced this order in
postgresql.conf.sample. This commit reorganizes the GUC groups in
guc_tables.c/h to match the updated ordering in the docs.

Reported-by: Álvaro Herrera
Reviewed-by: Álvaro Herrera, Alena Rybakina
Discussion: https://postgr.es/m/202501132046.m4mcvxxswznu%40alvherre.pgsql
2025-01-14 15:31:00 -05:00
Heikki Linnakangas
af8cd1639a Fix catcache invalidation of a list entry that's being built
If a new catalog tuple is inserted that belongs to a catcache list
entry, and cache invalidation happens while the list entry is being
built, the list entry might miss the newly inserted tuple.

To fix, change the way we detect concurrent invalidations while a
catcache entry is being built. Keep a stack of entries that are being
built, and apply cache invalidation to those entries in addition to
the real catcache entries. This is similar to the in-progress list in
relcache.c.

Back-patch to all supported versions.

Reviewed-by: Noah Misch
Discussion: https://www.postgresql.org/message-id/2234dc98-06fe-42ed-b5db-ac17384dc880@iki.fi
2025-01-14 14:28:49 +02:00
Michael Paquier
d35ea27e51 Move information about pgstats kinds into its own header pgstat_kind.h
This includes all the definitions for the various PGSTAT_KIND_* values,
the range allowed for custom stats kinds and some macros related all
that.

One use-case behind this split is the possibility to use this
information for frontend tools, without having to rely on pgstat.h and a
backend footprint.

Author: Michael Paquier
Reviewed-by: Bertrand Drouvot
Discussion: https://postgr.es/m/Z24fyb3ipXKR38oS@paquier.xyz
2025-01-14 12:43:07 +09:00
Michael Paquier
2c14037bb5 Refactor some code related to backend statistics
This commit changes the way pending backend statistics are tracked by
moving them into a new structure called PgStat_BackendPending, removing
PgStat_BackendPendingIO.  PgStat_BackendPending currently only includes
PgStat_PendingIO for the pending I/O stats.

pgstat_flush_backend() is extended with a "flags" argument to control
which parts of the stats of a backend should be flushed.

With this refactoring, it becomes easier to plug into backend statistics
more data.  A patch to add information related to WAL in this stats kind
is under discussion.

Author: Bertrand Drouvot
Discussion: https://postgr.es/m/Z3zqc4o09dM/Ezyz@ip-10-97-1-34.eu-west-3.compute.internal
2025-01-10 09:00:48 +09:00
Jeff Davis
229e7793d9 Fix duplicate typedef from commit a2f17f004d.
Reported-by: Thomas Munro
2025-01-08 15:25:05 -08:00
Jeff Davis
a2f17f004d Control collation behavior with a method table.
Previously, behavior branched based on the provider. A method table is
less error-prone and more flexible.

The ctype behavior will be addressed in an upcoming commit.

Reviewed-by: Andreas Karlsson
Discussion: https://postgr.es/m/2830211e1b6e6a2e26d845780b03e125281ea17b.camel%40j-davis.com
2025-01-08 14:26:46 -08:00
Bruce Momjian
50e6eb731d Update copyright for 2025
Backpatch-through: 13
2025-01-01 11:21:55 -05:00
Heikki Linnakangas
1f81b48a9d Mark CatalogSnapshotData static
Like CurrentSnapshotData, it should not be accessed directly outside
snapmgr.c.
2024-12-20 19:37:50 +02:00
Michael Paquier
9aea73fc61 Add backend-level statistics to pgstats
This adds a new variable-numbered statistics kind in pgstats, where the
object ID key of the stats entries is based on the proc number of the
backends.  This acts as an upper-bound for the number of stats entries
that can exist at once.  The entries are created when a backend starts
after authentication succeeds, and are removed when the backend exits,
making the stats entry exist for as long as their backend is up and
running.  These are not written to the pgstats file at shutdown (note
that write_to_file is disabled, as a safety measure).

Currently, these stats include only information about the I/O generated
by a backend, using the same layer as pg_stat_io, except that it is now
possible to know how much activity is happening in each backend rather
than an overall aggregate of all the activity.  A function called
pg_stat_get_backend_io() is added to access this data depending on the
PID of a backend.  The existing structure could be expanded in the
future to add more information about other statistics related to
backends, depending on requirements or ideas.

Auxiliary processes are not included in this set of statistics.  These
are less interesting to have than normal backends as they have dedicated
entries in pg_stat_io, and stats kinds of their own.

This commit includes also pg_stat_reset_backend_stats(), function able
to reset all the stats associated to a single backend.

Bump catalog version and PGSTAT_FILE_FORMAT_ID.

Author: Bertrand Drouvot
Reviewed-by: Álvaro Herrera, Kyotaro Horiguchi, Michael Paquier, Nazir
Bilal Yavuz
Discussion: https://postgr.es/m/ZtXR+CtkEVVE/LHF@ip-10-97-1-34.eu-west-3.compute.internal
2024-12-19 13:19:22 +09:00