Commit 719dcf3c42 introduced a field called CachedPlanType in
PlannedStmt to allow extensions to determine whether a cached plan is
generic or custom.
After discussion, the concepts that we want to track are a bit wider
than initially anticipated, as it is closer to knowing from which
"source" or "origin" a PlannedStmt has been generated or retrieved.
Custom and generic cached plans are a subset of that.
Based on the state of HEAD, we have been able to define two more
origins:
- "standard", for the case where PlannedStmt is generated in
standard_planner(), the most common case.
- "internal", for the fake PlannedStmt generated internally by some
query patterns.
This could be tuned in the future depending on what is needed. This
looks like a good starting point, at least. The default value is called
"UNKNOWN", provided as fallback value. This value is not used in the
core code, the idea is to let extensions building their own PlannedStmts
know about this new field.
Author: Michael Paquier <michael@paquier.xyz>
Co-authored-by: Sami Imseih <samimseih@gmail.com>
Discussion: https://postgr.es/m/aILaHupXbIGgF2wJ@paquier.xyz
If the client sent a query cancel request with backend PID 0, it
tripped an assertion. With assertions disabled, you got this in the
log instead:
LOG: invalid cancel request with PID 0
LOG: wrong key in cancel request for process 0
Query cancellations don't even require authentication, so we better
tolerate bogus requests. Fix by turning the assertion into a regular
runtime check.
Spotted while testing libpq behavior with a modified server that
didn't send BackendKeyData to the client.
Backpatch-through: 18
For many optional libraries, we extract the -L and -l switches needed
to link the library from a helper program such as llvm-config. In
some cases we put the resulting -L switches into LDFLAGS ahead of
-L switches specified via --with-libraries. That risks breaking
the user's intention for --with-libraries.
It's not such a problem if the library's -L switch points to a
directory containing only that library, but on some platforms a
library helper may "helpfully" offer a switch such as -L/usr/lib
that points to a directory holding all standard libraries. If the
user specified --with-libraries in hopes of overriding the standard
build of some library, the -L/usr/lib switch prevents that from
happening since it will come before the user-specified directory.
To fix, avoid inserting these switches directly into LDFLAGS during
configure, instead adding them to LIBDIRS or SHLIB_LINK. They will
still eventually get added to LDFLAGS, but only after the switches
coming from --with-libraries.
The same problem exists for -I switches: those coming from
--with-includes should appear before any coming from helper programs
such as llvm-config. We have not heard field complaints about this
case, but it seems certain that a user attempting to override a
standard library could have issues.
The changes for this go well beyond configure itself, however,
because many Makefiles have occasion to manipulate CPPFLAGS to
insert locally-desirable -I switches, and some of them got it wrong.
The correct ordering is any -I switches pointing at within-the-
source-tree-or-build-tree directories, then those from the tree-wide
CPPFLAGS, then those from helper programs. There were several places
that risked pulling in a system-supplied copy of libpq headers, for
example, instead of the in-tree files. (Commit cb36f8ec2 fixed one
instance of that a few months ago, but this exercise found more.)
The Meson build scripts may or may not have any comparable problems,
but I'll leave it to someone else to investigate that.
Reported-by: Charles Samborski <demurgos@demurgos.net>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/70f2155f-27ca-4534-b33d-7750e20633d7@demurgos.net
Backpatch-through: 13
When I prepared 71c0921b6 et al yesterday, I was thinking that the
logic involving explicitly freeing the node_list output was still
needed to dodge leakage bugs in libxml2. But I was misremembering:
we introduced that only because with early 2.13.x releases we could
not trust xmlParseBalancedChunkMemory's result code, so we had to
look to see if a node list was returned or not. There's no reason
to believe that xmlParseBalancedChunkMemory will fail to clean up
the node list when required, so simplify. (This essentially
completes reverting all the non-cosmetic changes in 6082b3d5d.)
Reported-by: Jim Jones <jim.jones@uni-muenster.de>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/997668.1753802857@sss.pgh.pa.us
Backpatch-through: 13
There've been a few complaints that it can be overly difficult to figure
out why the planner picked a Memoize plan. To help address that, here we
adjust the EXPLAIN output to display the following additional details:
1) The estimated number of cache entries that can be stored at once
2) The estimated number of unique lookup keys that we expect to see
3) The number of lookups we expect
4) The estimated hit ratio
Technically #4 can be calculated using #1, #2 and #3, but it's not a
particularly obvious calculation, so we opt to display it explicitly.
The original patch by Lukas Fittl only displayed the hit ratio, but
there was a fear that might lead to more questions about how that was
calculated. The idea with displaying all 4 is to be transparent which
may allow queries to be tuned more easily. For example, if #2 isn't
correct then maybe extended statistics or a manual n_distinct estimate can
be used to help fix poor plan choices.
Author: Ilia Evdokimov <ilya.evdokimov@tantorlabs.com>
Author: Lukas Fittl <lukas@fittl.com>
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/CAP53Pky29GWAVVk3oBgKBDqhND0BRBN6yTPeguV_qSivFL5N_g%40mail.gmail.com
This mostly reverts commit 6082b3d5d, "Use xmlParseInNodeContext
not xmlParseBalancedChunkMemory". It turns out that
xmlParseInNodeContext will reject text chunks exceeding 10MB, while
(in most libxml2 versions) xmlParseBalancedChunkMemory will not.
The bleeding-edge libxml2 bug that we needed to work around a year
ago is presumably no longer a factor, and the argument that
xmlParseBalancedChunkMemory is semi-deprecated is not enough to
justify a functionality regression. Hence, go back to doing it
the old way.
Reported-by: Michael Paquier <michael@paquier.xyz>
Author: Michael Paquier <michael@paquier.xyz>
Co-authored-by: Erik Wienhold <ewie@ewie.name>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/aIGknLuc8b8ega2X@paquier.xyz
Backpatch-through: 13
Commit 473a575e05 purported to make this
function stash the error message in *syncrep_parse_result_p, but
it didn't actually.
As a result, an attempt to set synchronous_standby_names to any value
that does not parse resulted in a generic "parser failed." message
rather than anything more specific. This fixes that.
Discussion: http://postgr.es/m/CA+TgmoYF9wPNZ-Q_EMfib_espgHycY-eX__6Tzo2GpYpVXqCdQ@mail.gmail.com
Backpatch-through: 18
The callback added in fc415edf8c used to check if there is any pending
data to flush for fixed-numbered statistics, done by looping across all
the builtin and custom stats kinds with a call to have_fixed_pending_cb,
is proving to able to show in workloads that do not report any stats
(read-only, no function calls, no WAL, no IO, etc). The code used in
v17 was cheaper than that what HEAD has introduced, relying on three
boolean checks for WAL, SLRU and IO stats.
This commit switches the code to use a more efficient approach than
fc415edf8c, with a single boolean flag that can be switched to "true"
by any fixed-numbered stats kinds to force pgstat_report_stat() to go
through one round of reports. The flag is reset by pgstat_report_stat()
once a full round of reports is done. The flag being false means that
fixed-numbered stats kinds saw no activity, and that there is no pending
data to flush.
ac000fca74 took one step in improving the performance by reducing the
number of stats kinds that the backend can hold. This commit takes a
more drastic step by bringing back the code efficiency to what it was
before v18 with a cheap check at the beginning of pgstat_report_stat()
for its fast-exit path.
The callback have_static_pending_cb is removed as an effect of all that.
Reported-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/eb224uegsga2hgq7dfq3ps5cduhpqej7ir2hjxzzozjthrekx5@dysei6buqthe
Backpatch-through: 18
If the number of sync requests is big enough, the palloc() call in
AbsorbSyncRequests() will attempt to allocate more than 1 GB of memory,
resulting in failure. This can lead to an infinite loop in the checkpointer
process, as it repeatedly fails to absorb the pending requests.
This commit introduces the following changes to cope with this problem:
1. Turn pending checkpointer requests array in shared memory into a bounded
ring buffer.
2. Limit maximum ring buffer size to 10M items.
3. Make AbsorbSyncRequests() process requests incrementally in 10K batches.
Even #2 makes the whole queue size fit the maximum palloc() size of 1 GB.
of continuous lock holding.
This commit is for master only. Simpler fix, which just limits a request
queue size to 10M, will be backpatched.
Reported-by: Ekaterina Sokolova <e.sokolova@postgrespro.ru>
Discussion: https://postgr.es/m/db4534f83a22a29ab5ee2566ad86ca92%40postgrespro.ru
Author: Maxim Orlov <orlovmg@gmail.com>
Co-authored-by: Xuneng Zhou <xunengzhou@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
Similar checks are done for the mandatory table AM callbacks. A portion
of the index AM callbacks are optional and can be NULL; the rest is
mandatory and is documented as such in the documentation and in amapi.h.
These checks are useful to detect quickly if all the mandatory callbacks
are defined when implementing a new index access method, as the
assertions are run when loading the AM.
Author: Japin Li <japinli@hotmail.com>
Discussion: https://postgr.es/m/ME0P300MB0445795D31CEAB92C58B41FDB651A@ME0P300MB0445.AUSP300.PROD.OUTLOOK.COM
Remove a bunch of PG_TRY constructs, de-volatilize related
variables, remove some PQclear calls in error paths.
Aside from making the code simpler and shorter, this should
provide some marginal performance gains.
For ease of review, I did not re-indent code within the removed
PG_TRY constructs. That'll be done in a separate patch.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Matheus Alcantara <matheusssilv97@gmail.com>
Discussion: https://postgr.es/m/2976982.1748049023@sss.pgh.pa.us
Commit 232d8caea fixed a case where postgres_fdw could lose track
of a PGresult object, resulting in a process-lifespan memory leak.
But I have little faith that there aren't other potential PGresult
leakages, now or in future, in the backend modules that use libpq.
Therefore, this patch proposes infrastructure that makes all
PGresults returned from libpq act as though they are palloc'd
in the CurrentMemoryContext (with the option to relocate them to
another context later). This should greatly reduce the risk of
careless leaks, and it also permits removal of a bunch of code
that attempted to prevent such leaks via PG_TRY blocks.
This patch adds infrastructure that wraps each PGresult in a
"libpqsrv_PGresult" that provides a memory context reset callback
to PQclear the PGresult. Code using this abstraction is inherently
memory-safe to the same extent as we are accustomed to in most backend
code. Furthermore, we add some macros that automatically redirect
calls of the libpq functions concerned with PGresults to use this
infrastructure, so that almost no source-code changes are needed to
wheel this infrastructure into place in all the backend code that
uses libpq.
Perhaps in future we could create similar infrastructure for
PGconn objects, but there seems less need for that.
This patch just creates the infrastructure and makes relevant code
use it, including reverting 232d8caea in favor of this mechanism.
A good deal of follow-on simplification is possible now that we don't
have to be so cautious about freeing PGresults, but I'll put that in
a separate patch.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Matheus Alcantara <matheusssilv97@gmail.com>
Discussion: https://postgr.es/m/2976982.1748049023@sss.pgh.pa.us
This flag was effectively a no-op in EXEC_BACKEND (ie, Windows)
builds, because it was kept in the process-local HTAB struct,
and it could only ever become set in the postmaster's copy.
The simplest fix is to move it to the shared HASHHDR struct.
We could keep a copy in HTAB as well, as we do with keysize
and some other fields, but the "too much contention" argument
doesn't seem to apply here: we only examine isfixed during
element_alloc(), which had better not get hit very often for
a shared hashtable.
This oversight dates to 7c797e719 which invented the option.
But back-patching doesn't seem appropriate given the lack of
field complaints. If there is anyone running an affected
workload on Windows, they might be unhappy about the behavior
changing in a minor release.
Author: Aidar Imamov <a.imamov@postgrespro.ru>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/4d0cb35ff01c5c74d2b9a582ecb73823@postgrespro.ru
Previously, if a background worker crashed (e.g., due to a SIGKILL) and
the server restarted due to restart_after_crash being enabled,
the worker was not restarted as expected. Background workers without
the never-restart flag should automatically restart in this case.
This issue was introduced in commit 28a520c0b7, which failed to reset
the rw_pid field in the RegisteredBgWorker struct for the crashed worker.
This commit fixes the problem by resetting rw_pid for all eligible
background workers during the crash-and-restart cycle.
Back-patched to v18, where the bug was introduced.
Bug fix patches were proposed by Andrey Rudometov and ChangAo Chen,
but this commit uses a different approach.
Reported-by: Andrey Rudometov <unlimitedhikari@gmail.com>
Reported-by: ChangAo Chen <cca5507@qq.com>
Author: Andrey Rudometov <unlimitedhikari@gmail.com>
Author: ChangAo Chen <cca5507@qq.com>
Co-authored-by: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: ChangAo Chen <cca5507@qq.com>
Reviewed-by: Shveta Malik <shveta.malik@gmail.com>
Discussion: https://postgr.es/m/CAF6JsWiO=i24qYitWe6ns1sXqcL86rYxdyU+pNYk-WueKPSySg@mail.gmail.com
Discussion: https://postgr.es/m/tencent_E00A056B3953EE6440F0F40F80EC30427D09@qq.com
Backpatch-through: 18
LatchWaitSetPostmasterDeathPos, the latch event position for the
postmaster death event, is initialized under IsUnderPostmaster.
WaitLatch() considered it as a valid wait target in single-user mode
(!IsUnderPostmaster), which was incorrect.
One code path found to fail with an assertion failure is a database drop
in single-user mode while waiting in WaitForProcSignalBarrier() after
the drop.
Oversight in commit 84e5b2f07a.
Author: Patrick Stählin <me@packi.ch>
Co-authored-by: Ronan Dunklau <ronan.dunklau@aiven.io>
Discussion: https://postgr.es/m/18996-3a2744c8140488de@postgresql.org
Backpatch-through: 18
This function is declared as returning a uint8, but it returns a
bool in one code path. To fix, return (uint8) 0 instead of false
there. This should behave exactly the same as before, but it might
prevent future compiler complaints.
Oversight in commit a892234f83.
Author: Julien Rouhaud <rjuju123@gmail.com>
Discussion: https://postgr.es/m/aIHluT2isN58jqHV%40jrouhaud
PlannedStmt gains a new field, called CachedPlanType, able to track if a
given plan tree originates from the cache and if we are dealing with a
generic or custom cached plan.
This field can be used for monitoring or statistical purposes, in the
executor hooks, for example, based on the planned statement attached to
a QueryDesc. A patch is under discussion for pg_stat_statements to
provide an equivalent of the counters in pg_prepared_statements for
custom and generic plans, to provide a more global view of such data, as
this data is now restricted to the current session.
The concept introduced in this commit is useful on its own, and has been
extracted from a larger patch by the same author.
Author: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAA5RZ0uFw8Y9GCFvafhC=OA8NnMqVZyzXPfv_EePOt+iv1T-qQ@mail.gmail.com
Solaris has never bothered to add "const" to the second argument
of PAM conversation procs, as all other Unixen did decades ago.
This resulted in an "incompatible pointer" compiler warning when
building --with-pam, but had no more serious effect than that,
so we never did anything about it. However, as of GCC 14 the
case is an error not warning by default.
To complicate matters, recent OpenIndiana (and maybe illumos
in general?) *does* supply the "const" by default, so we can't
just assume that platforms using our solaris template need help.
What we can do, short of building a configure-time probe,
is to make solaris.h #define _PAM_LEGACY_NONCONST, which
causes OpenIndiana's pam_appl.h to revert to the traditional
definition, and hopefully will have no effect anywhere else.
Then we can use that same symbol to control whether we include
"const" in the declaration of pam_passwd_conv_proc().
Bug: #18995
Reported-by: Andrew Watkins <awatkins1966@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18995-82058da9ab4337a7@postgresql.org
Backpatch-through: 13
lwlock.c, lwlock.h, and wait_event_names.txt each contain a list of
built-in LWLock tranches. It is easy to miss one or the other when
adding or removing tranches, and discrepancies have adverse effects
(e.g., breaking JOINs between pg_stat_activity and pg_wait_events).
This commit moves the lists of built-in tranches in lwlock.{c,h} to
lwlocklist.h and adds a cross-check to the script that generates
lwlocknames.h. If the lists do not match exactly, building will
fail.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/aHpOgwuFQfcFMZ/B%40ip-10-97-1-34.eu-west-3.compute.internal
Logical replication requires reliable conflict detection to maintain data
consistency across nodes. To achieve this, we must prevent premature
removal of tuples deleted by other origins and their associated commit_ts
data by VACUUM, which could otherwise lead to incorrect conflict reporting
and resolution.
This patch introduces a mechanism to retain deleted tuples on the
subscriber during the application of concurrent transactions from remote
nodes. Retaining these tuples allows us to correctly ignore concurrent
updates to the same tuple. Without this, an UPDATE might be misinterpreted
as an INSERT during resolutions due to the absence of the original tuple.
Additionally, we ensure that origin metadata is not prematurely removed by
vacuum freeze, which is essential for detecting update_origin_differs and
delete_origin_differs conflicts.
To support this, a new replication slot named pg_conflict_detection is
created and maintained by the launcher on the subscriber. Each apply
worker tracks its own non-removable transaction ID, which the launcher
aggregates to determine the appropriate xmin for the slot, thereby
retaining necessary tuples.
Conflict information retention (deleted tuples and commit_ts) can be
enabled per subscription via the retain_conflict_info option. This is
disabled by default to avoid unnecessary overhead for configurations that
do not require conflict resolution or logging.
During upgrades, if any subscription on the old cluster has
retain_conflict_info enabled, a conflict detection slot will be created to
protect relevant tuples from deletion when the new cluster starts.
This is a foundational work to correctly detect update_deleted conflict
which will be done in a follow-up patch.
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: shveta malik <shveta.malik@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: Nisha Moond <nisha.moond412@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Discussion: https://postgr.es/m/OS0PR01MB5716BE80DAEB0EE2A6A5D1F5949D2@OS0PR01MB5716.jpnprd01.prod.outlook.com
Commit 112faf1378 introduced a translation marker in libpq-be-fe-helpers.h,
but this caused build failures on some platforms—such as the one reported
by buildfarm member indri—due to linker issues with dblink. This is the same
problem previously addressed in commit 213c959a29.
To fix the issue, this commit removes the translation marker from
libpq-be-fe-helpers.h, following the approach used in 213c959a29.
It also removes the associated gettext_noop() calls added in commit
112faf1378, as they are no longer needed.
While reviewing this, a gettext_noop() call was also found in
contrib/basic_archive. Since contrib modules don't support translation,
this call has been removed as well.
Per buildfarm member indri.
Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Discussion: https://postgr.es/m/0e6299d9-608a-4ffa-aeb1-40cb8a99000b@oss.nttdata.com
Previously, NOTICE, WARNING, and similar messages received from remote
servers over replication, postgres_fdw, or dblink connections were printed
directly to stderr on the local server (e.g., the subscriber). As a result,
these messages lacked log prefixes (e.g., timestamp), making them harder
to trace and correlate with other log entries.
This commit addresses the issue by introducing a custom notice receiver
for replication, postgres_fdw, and dblink connections. These messages
are now logged via ereport(), ensuring they appear in the logs with proper
formatting and context, which improves clarity and aids in debugging.
Author: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/CALDaNm2xsHpWRtLm-VL_HJCsaE3+1Y_n-jDEAr3-suxVqc3xoQ@mail.gmail.com
In commit b262ad440, we introduced an optimization that reduces an IS
[NOT] NULL qual on a NOT NULL column to constant true or constant
false, provided we can prove that the input expression of the NullTest
is not nullable by any outer joins or grouping sets. This deduction
happens quite late in the planner, during the distribution of quals to
rels in query_planner. However, this approach has some drawbacks: we
can't perform any further folding with the constant, and it turns out
to be prone to bugs.
Ideally, this deduction should happen during constant folding.
However, the per-relation information about which columns are defined
as NOT NULL is not available at that point. This information is
currently collected from catalogs when building RelOptInfos for base
or "other" relations.
This patch moves the collection of NOT NULL attribute information for
relations before pull_up_sublinks, storing it in a hash table keyed by
relation OID. It then uses this information to perform the NullTest
deduction for Vars during constant folding. This also makes it
possible to leverage this information to pull up NOT IN subqueries.
Note that this patch does not get rid of restriction_is_always_true
and restriction_is_always_false. Removing them would prevent us from
reducing some IS [NOT] NULL quals that we were previously able to
reduce, because (a) the self-join elimination may introduce new IS NOT
NULL quals after constant folding, and (b) if some outer joins are
converted to inner joins, previously irreducible NullTest quals may
become reducible.
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAMbWs4-bFJ1At4btk5wqbezdu8PLtQ3zv-aiaY3ry9Ymm=jgFQ@mail.gmail.com
There are several pieces of catalog information that need to be
retrieved for a relation during the early stage of planning. These
include relhassubclass, which is used to clear the inh flag if the
relation has no children, as well as a column's attgenerated and
default value, which are needed to expand virtual generated columns.
More such information may be required in the future.
Currently, these pieces of catalog data are collected in multiple
places, resulting in repeated table_open/table_close calls for each
relation in the rangetable. This patch centralizes the collection of
all required early-stage catalog information into a single loop over
the rangetable, allowing each relation to be opened and closed only
once.
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAMbWs4-bFJ1At4btk5wqbezdu8PLtQ3zv-aiaY3ry9Ymm=jgFQ@mail.gmail.com
Currently, we expand virtual generated columns after we have pulled up
any SubLinks within the query's quals. This ensures that the virtual
generated column references within SubLinks that should be transformed
into joins are correctly expanded. This approach works well and has
posed no issues.
In an upcoming patch, we plan to centralize the collection of catalog
information needed early in the planner. This will help avoid
repeated table_open/table_close calls for relations in the rangetable.
Since this information is required during sublink pull-up, we are
moving the expansion of virtual generated columns to occur beforehand.
To achieve this, if any EXISTS SubLinks can be pulled up, their
rangetables are processed just before pulling them up.
Author: Richard Guo <guofenglinux@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAMbWs4-bFJ1At4btk5wqbezdu8PLtQ3zv-aiaY3ry9Ymm=jgFQ@mail.gmail.com
The only practical effect of these changes is to avoid a useless
list_copy() operation when there is a single hashclause. That's
never going to make any noticeable performance difference, but
the code is arguably clearer this way, especially if we take the
opportunity to add some comments so that readers don't have to
reverse-engineer the usage of these local variables. Also add
some braces for better/more consistent style.
Author: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAHewXNnHBOO9NEa=NBDYOrwZL4oHu2NOcTYvqyNyWEswo8f5OQ@mail.gmail.com
If a crash occurs while writing a WAL record that spans multiple pages, the
recovery process marks the page with the XLP_FIRST_IS_OVERWRITE_CONTRECORD
flag. However, logical decoding currently attempts to read the full WAL
record based on its expected size before checking this flag, which can lead
to an infinite wait if the remaining data is never written (e.g., no activity
after crash).
This patch updates the logic first to read the page header and check for
the XLP_FIRST_IS_OVERWRITE_CONTRECORD flag before attempting to reconstruct
the full WAL record. If the flag is set, decoding correctly identifies
the record as incomplete and avoids waiting for WAL data that will never
arrive.
Discussion: https://postgr.es/m/CAAKRu_ZCOzQpEumLFgG_%2Biw3FTa%2BhJ4SRpxzaQBYxxM_ZAzWcA%40mail.gmail.com
Discussion: https://postgr.es/m/CALDaNm34m36PDHzsU_GdcNXU0gLTfFY5rzh9GSQv%3Dw6B%2BQVNRQ%40mail.gmail.com
Author: Vignesh C <vignesh21@gmail.com>
Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
Backpatch-through: 13
Instead of laboriously computing the exact output length, use strlen
to get an upper bound cheaply. (This is still O(N) of course, but
the constant factor is a lot less.) This will typically result in
overallocating the output datum, but that's of little concern since
it's a short-lived allocation in just about all use-cases.
A simple microbenchmark showed about 40% speedup for long input
strings.
While here, make some cosmetic cleanups and add a test case that
covers the double-backslash code path in byteain and byteaout.
Author: Steven Niu <niushiji@gmail.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Reviewed-by: Stepan Neretin <slpmcf@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/ca315729-140b-426e-81a6-6cd5cfe7ecc5@gmail.com
If a MERGE inside a CTE attempts an UPDATE or DELETE on a table with
BEFORE ROW triggers, and a concurrent UPDATE or DELETE happens, the
merge code would fail (crashing in the case of an UPDATE action, and
potentially executing the wrong action for a DELETE action).
This is the same issue that 9321c79c86 attempted to fix, except now
for a MERGE inside a CTE. As noted in 9321c79c86, what needs to happen
is for the trigger code to exit early, returning the TM_Result and
TM_FailureData information to the merge code, if a concurrent
modification is detected, rather than attempting to do an EPQ
recheck. The merge code will then do its own rechecking, and rescan
the action list, potentially executing a different action in light of
the concurrent update. In particular, the trigger code must never call
ExecGetUpdateNewTuple() for MERGE, since that is bound to fail because
MERGE has its own per-action projection information.
Commit 9321c79c86 did this using estate->es_plannedstmt->commandType
in the trigger code to detect that a MERGE was being executed, which
is fine for a plain MERGE command, but does not work for a MERGE
inside a CTE. Fix by passing that information to the trigger code as
an additional parameter passed to ExecBRUpdateTriggers() and
ExecBRDeleteTriggers().
Back-patch as far as v17 only, since MERGE cannot appear inside a CTE
prior to that. Additionally, take care to preserve the trigger ABI in
v17 (though not in v18, which is still in beta).
Bug: #18986
Reported-by: Yaroslav Syrytsia <me@ys.lc>
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/18986-e7a8aac3d339fa47@postgresql.org
Backpatch-through: 17
We have an assertion to ensure that a command tag has been assigned by
the time we're done executing, but if we happen to execute a command
with no queries, the assertion would fail. Per discussion, rather than
contort things to get a tag assigned, just remove the assertion.
Oversight in 2f9661311b. That commit also retained a comment that
explained logic that had been adjacent to it but diffused into various
places, leaving none apt to keep part of the comment. Remove that part,
and rewrite what remains for extra clarity.
Bug: #18984
Backpatch-through: 13
Reported-by: Aleksander Alekseev <aleksander@tigerdata.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Michaël Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/18984-0f4778a6599ac3ae@postgresql.org
The terms used in wait_event_names.txt and lwlock.c were inconsistent
for MultiXactOffsetSLRU and MultiXactMemberSLRU, which could cause joins
between pg_wait_events and pg_stat_activity to fail. lwlock.c is
adjusted in this commit to what the historical name of the event has
always been, and what is documented.
Oversight in 53c2a97a92. 08b9b9e043 has fixed a similar
inconsistency some time ago.
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@kurilemu.de>
Discussion: https://postgr.es/m/aHdxN0D0hKXzHFQG@ip-10-97-1-34.eu-west-3.compute.internal
Backpatch-through: 17
Avoid dependence on setlocale().
strcoll(), etc., are not called directly; all collation-sensitive
calls should go through pg_locale.c and use the appropriate
provider. By setting LC_COLLATE to C, we avoid accidentally depending
on libc behavior when using a different provider.
No behavior change in the backend, but it's possible that some
extensions will be affected. Such extensions should be updated to use
the pg_locale_t APIs.
Discussion: https://postgr.es/m/9875f7f9-50f1-4b5d-86fc-ee8b03e8c162@eisentraut.org
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
_bt_first need only store one ScanKeyData struct on the stack for the
purposes of building an IS NOT NULL key based on an implied NOT NULL
constraint. We don't need INDEX_MAX_KEYS-many ScanKeyData structs.
This saves us a little over 2KB in stack space. It's possible that this
has some performance benefit. It also seems simpler and more direct.
It isn't possible for more than a single index attribute to need its own
implied IS NOT NULL key: the first such attribute/IS NOT NULL key always
makes _bt_first stop adding additional boundary keys to startKeys[].
Using INDEX_MAX_KEYS-many ScanKeyData entries was (at best) misleading.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Mircea Cadariu <cadariu.mircea@gmail.com>
Discussion: https://postgr.es/m/CAH2-Wzm=1kJMSZhhTLoM5BPbwQNWxUj-ynOEh=89ptDZAVgauw@mail.gmail.com
This code used a NO_LZ4_SUPPORT() macro to issue an error in the code
paths where LZ4 [de]compression is attempted but the build does not
support it. This commit refactors the code to use a more flexible error
message so as it can be used for other compression methods, where the
method is given in input of macro.
Extracted from a larger patch by the same author.
Author: Nikhil Kumar Veldanda <veldanda.nikhilkumar17@gmail.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Discussion: https://postgr.es/m/CAFAfj_HX84EK4hyRYw50AOHOcdVi-+FFwAAPo7JHx4aShCvunQ@mail.gmail.com
The pgoutput plugin initializes optional parameters like "binary" with
default values at the start of processing. However, the "origin"
parameter was previously missed and left without explicit initialization.
Although the PGOutputData struct, which holds these settings,
is zero-initialized at allocation (resulting in publish_no_origin field
for "origin" parameter being false by default), this default was not
set explicitly, unlike other parameters.
This commit adds explicit initialization of the "origin" parameter to
ensure consistency and clarity in how defaults are handled.
Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Euler Taveira <euler@eulerto.com>
Discussion: https://postgr.es/m/d2790f10-238d-4cb5-a743-d9d2a9dd900f@oss.nttdata.com
The grammar was a little shaky and confusing here, so word-smith it
a bit. Also, adjust the comments in pg_ident.conf.sample to use the
same terminology as the SGML docs, in particular "DATABASE-USERNAME"
not "PG-USERNAME".
Back-patch appropriate subsets. I did not risk changing
pg_ident.conf.sample in released branches, but it still seems OK
to change it in v18.
Reported-by: Alexey Shishkin <alexey.shishkin@enterprisedb.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: David G. Johnston <david.g.johnston@gmail.com>
Discussion: https://postgr.es/m/175206279327.3157504.12519088928605422253@wrigleys.postgresql.org
Backpatch-through: 13
It's impossible to reach this case with either ra or rb being
WJB_DONE, because our earlier checks that the structure and
length of the inputs match should guarantee that we reach their
ends simultaneously. However, the comment completely fails to
explain this, and the Asserts don't cover it either. The comment
is pretty obscure anyway, so rewrite it, and extend the Asserts
to reject WJB_DONE.
This is only cosmetic, so no need for back-patch.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/0c623e8a204187b87b4736792398eaf1@postgrespro.ru
Because not every path through JsonbIteratorNext() sets val->type,
some compilers complain that compareJsonbContainers() is comparing
possibly-uninitialized values. The paths that don't set it return
WJB_DONE, WJB_END_ARRAY, or WJB_END_OBJECT, so it's clear by
manual inspection that the "(ra == rb)" code path is safe, and
indeed we aren't seeing warnings about that. But the (ra != rb)
case is much less obviously safe. In Assert-enabled builds it
seems that the asserts rejecting WJB_END_ARRAY and WJB_END_OBJECT
persuade gcc 15.x not to warn, which makes little sense because
it's impossible to believe that the compiler can prove of its
own accord that ra/rb aren't WJB_DONE here. (In fact they never
will be, so the code isn't wrong, but why is there no warning?)
Without Asserts, the appearance of warnings is quite unsurprising.
We discussed fixing this by converting those two Asserts into
pg_assume, but that seems not very satisfactory when it's so unclear
why the compiler is or isn't warning: the warning could easily
reappear with some other compiler version. Let's fix it in a less
magical, more future-proof way by changing JsonbIteratorNext()
so that it always does set val->type. The cost of that should be
pretty negligible, and it makes the function's API spec less squishy.
Reported-by: Erik Rijkers <er@xs4all.nl>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/988bf1bc-3f1f-99f3-bf98-222f1cd9dc5e@xs4all.nl
Discussion: https://postgr.es/m/0c623e8a204187b87b4736792398eaf1@postgrespro.ru
Backpatch-through: 13
If the system-name field of a pg_ident.conf line is a regex
containing capturing parentheses, you can write \1 in the
user-name field to represent the captured part of the system
name. But what happens if you write \1 more than once?
The only reasonable expectation IMO is that each \1 gets
replaced, but presently our code replaces only the first.
Fix that.
Also, improve the tests for this feature to exercise cases
where a non-empty string needs to be substituted for \1.
The previous testing didn't inspire much faith that it
was verifying correct operation of the substitution code.
Given the lack of field complaints about this, I don't
feel a need to back-patch.
Reported-by: David G. Johnston <david.g.johnston@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAKFQuwZu6kZ8ZPvJ3pWXig+6UX4nTVK-hdL_ZS3fSdps=RJQQQ@mail.gmail.com
The values of the "result" variables in these functions are
always integers; using a float8 variable accomplishes nothing
except to incur useless conversions to and from float. While
that wastes a few nanoseconds, these functions aren't all that
time-critical. But it seems worth fixing to remove possible
reader confusion.
Also, in the case of date2isoyear(), "result" is a very poorly
chosen variable name because it is *not* the function's result.
Rename it to "week", and do the same in date2isoweek() for
consistency.
Since this is mostly cosmetic, there seems little need
for back-patch.
Author: Sergey Fukanchik <s.fukanchik@postgrespro.ru>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/6323a-68726500-1-7def9d00@137821581
