For AIO we execute completion callbacks in critical sections (to ensure that
AIO can in the future be used for WAL, which in turn requires that we can call
completion callbacks in critical sections, to get the resources for WAL
io). To report checksum errors a backend now has to call
pgstat_prepare_report_checksum_failure(), before entering a critical section,
which guarantees the relevant pgstats entry is in shared memory, the relevant
DSM segment is mapped into the backend's memory and the address is known via a
PgStat_EntryRef.
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/wkjj4p2rmkevutkwc6tewoovdqznj6c6nvjmvii4oo5wmbh5sr@retq7d6uqs4j
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
Some of these comments have been wrong for a while (12f3867f55), some I
recently introduced (da7226993f, 55b454d0e1). This includes an update to a
comment in FlushBuffer(), which will be copied in a future commit.
These changes seem big enough to be worth doing in separate commits.
Suggested-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20250319212530.80.nmisch@google.com
Checksum failure stats could be attributed to the wrong database in two cases:
- when a read of a shared relation encountered a checksum error , it would be
attributed to the current database, instead of the "database" representing
shared relations
- when using CREATE DATABASE ... STRATEGY WAL_LOG checksum errors in the
source database would be attributed to the current database
The checksum stats reporting via PageIsVerifiedExtended(PIV_REPORT_STAT) does
not have access to the information about what database a page belongs to.
This fixes the issue by removing PIV_REPORT_STAT and delegating the
responsibility to report stats to the caller, which now can learn about the
number of stats via a new optional argument.
As this changes the signature of PageIsVerifiedExtended() and all callers
should adapt to the new signature, use the occasion to rename the function to
PageIsVerified() and remove the compatibility macro.
We could instead have fixed this by adding information about the database to
the args of PageIsVerified(), but there are soon-to-be-applied patches that
need to separate the stats reporting from the PageIsVerified() call
anyway. Those patches also include testing for the failure paths, something we
inexplicably have not had.
As there is no caller of pgstat_report_checksum_failure() left, remove it.
It'd be possible, but awkward to fix this in the back branches. We considered
doing the work not quite worth it, as mis-attributed stats should still elicit
concern. The emitted error messages do allow to attribute the errors
correctly.
Discussion: https://postgr.es/m/5tyic6epvdlmd6eddgelv47syg2b5cpwffjam54axp25xyq2ga@ptwkinxqo3az
Discussion: https://postgr.es/m/mglpvvbhighzuwudjxzu4br65qqcxsnyvio3nl4fbog3qknwhg@e4gt7npsohuz
This commit introduces SVE implementations of pg_popcount{32,64}.
Unlike the Neon versions, we need an additional configure-time
check to determine if the compiler supports SVE intrinsics, and we
need a runtime check to determine if the current CPU supports SVE
instructions. Our testing showed that the SVE implementations are
much faster for larger inputs and are comparable to the status
quo for smaller inputs.
Author: "Devanga.Susmitha@fujitsu.com" <Devanga.Susmitha@fujitsu.com>
Co-authored-by: "Chiranmoy.Bhattacharya@fujitsu.com" <Chiranmoy.Bhattacharya@fujitsu.com>
Co-authored-by: "Malladi, Rama" <ramamalladi@hotmail.com>
Reviewed-by: John Naylor <johncnaylorls@gmail.com>
Reviewed-by: Kirill Reshke <reshkekirill@gmail.com>
Discussion: https://postgr.es/m/010101936e4aaa70-b474ab9e-b9ce-474d-a3ba-a3dc223d295c-000000%40us-west-2.amazonses.com
Discussion: https://postgr.es/m/OSZPR01MB84990A9A02A3515C6E85A65B8B2A2%40OSZPR01MB8499.jpnprd01.prod.outlook.com
This commit introduces Neon implementations of pg_popcount{32,64},
pg_popcount(), and pg_popcount_masked(). As in simd.h, we assume
that all available AArch64 hardware supports Neon, so we don't need
any new configure-time or runtime checks. Some compilers already
emit Neon instructions for these functions, but our hand-rolled
implementations for pg_popcount() and pg_popcount_masked()
performed better in testing, likely due to better instruction-level
parallelism.
Author: "Chiranmoy.Bhattacharya@fujitsu.com" <Chiranmoy.Bhattacharya@fujitsu.com>
Reviewed-by: John Naylor <johncnaylorls@gmail.com>
Discussion: https://postgr.es/m/010101936e4aaa70-b474ab9e-b9ce-474d-a3ba-a3dc223d295c-000000%40us-west-2.amazonses.com
This macro protects x86_64-specific code, and a subsequent commit
will introduce AArch64-specific versions of that code. To prevent
confusion, let's rename it to clearly indicate that it's for
x86_64. We should likely move this code to its own file (perhaps
merging it with the AVX-512 popcount code), but that is left as a
future exercise.
Reviewed-by: "Chiranmoy.Bhattacharya@fujitsu.com" <Chiranmoy.Bhattacharya@fujitsu.com>
Reviewed-by: John Naylor <johncnaylorls@gmail.com>
Discussion: https://postgr.es/m/010101936e4aaa70-b474ab9e-b9ce-474d-a3ba-a3dc223d295c-000000%40us-west-2.amazonses.com
Remove setlocale() and _configthreadlocal() as fallback strategy on
systems that don't have uselocale(), where ECPG tries to control
LC_NUMERIC formatting on input and output of floating point numbers. It
was probably broken on some systems (NetBSD), and the code was also
quite messy and complicated, with obsolete configure tests (Windows).
It was also arguably broken, or at least had unstated environmental
requirements, if pgtypeslib code was called directly.
Instead, introduce PG_C_LOCALE to refer to the "C" locale as a locale_t
value. It maps to the special constant LC_C_LOCALE when defined by libc
(macOS, NetBSD), or otherwise uses a process-lifetime locale_t that is
allocated on first use, just as ECPG previously did itself. The new
replacement might be more widely useful. Then change the float parsing
and printing code to pass that to _l() functions where appropriate.
Unfortunately the portability of those functions is a bit complicated.
First, many obvious and useful _l() functions are missing from POSIX,
though most standard libraries define some of them anyway. Second,
although the thread-safe save/restore technique can be used to replace
the missing ones, Windows and NetBSD refused to implement standard
uselocale(). They might have a point: "wide scope" uselocale() is hard
to combine with other code and error-prone, especially in library code.
Luckily they have the _l() functions we want so far anyway. So we have
to be prepared for both ways of doing things:
1. In ECPG, use strtod_l() for parsing, and supply a port.h replacement
using uselocale() over a limited scope if missing.
2. Inside our own snprintf.c, use three different approaches to format
floats. For frontend code, call libc's snprintf_l(), or wrap libc's
snprintf() in uselocale() if it's missing. For backend code, snprintf.c
can keep assuming that the global locale's LC_NUMERIC is "C" and call
libc's snprintf() without change, for now.
(It might eventually be possible to call our in-tree Ryū routines to
display floats in snprintf.c, given the C-locale-always remit of our
in-tree snprintf(), but this patch doesn't risk changing anything that
complicated.)
Author: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Tristan Partin <tristan@partin.io>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Discussion: https://postgr.es/m/CWZBBRR6YA8D.8EHMDRGLCKCD%40neon.tech
This was left out of the original patch for virtual generated columns
(commit 83ea6c5402).
This just involves a bit of extra work in the executor to expand the
generation expressions and run a "IS NOT NULL" test against them.
There is also a bit of work to make sure that not-null constraints are
checked during a table rewrite.
Author: jian he <jian.universality@gmail.com>
Reviewed-by: Xuneng Zhou <xunengzhou@gmail.com>
Reviewed-by: Navneet Kumar <thanit3111@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/CACJufxHArQysbDkWFmvK+D1TPHQWWTxWN15cMuUaTYX3xhQXgg@mail.gmail.com
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
As revised by commit 9324c8c58, PG_MODULE_MAGIC constructed a
struct initializer containing both designated fields and a
non-designated "0". That's okay in C, but not in C++, with
the result that extensions written in C++ failed to compile.
Change it to use only designated field initializers.
Author: Yurii Rashkovskii <yrashk@omnigres.com>
Discussion: https://postgr.es/m/CAG=VW14mctsR543gpzLCuJ9JgJqwa=ptmBfGvxEjs+k8Jf7-Bg@mail.gmail.com
Commit 62d712ecfd introduced the capability to calculate the same
queryId for queries with different lengths of constants in a list for an
IN clause. This behavior was originally enabled with a GUC
query_id_squash_values. After a discussion about the value of such a
GUC, it was decided to back out of the use of a GUC and make the
squashing behavior the only available option.
Author: Sami Imseih <samimseih@gmail.com>
Discussion: https://postgr.es/m/Z-LZyygkkNyA8-kR@msg.df7cb.de
Discussion: https://postgr.es/m/CA+q6zcVTK-3C-8NWV1oY2NZrvtnMCDqnyYYyk1T7WMUG65MeOQ@mail.gmail.com
This involves four different implementation strategies:
1. For Windows, we now require _configthreadlocale() to be available
and work (commit f1da075d9a), and the documentation says that the
object returned by localeconv() is in thread-local memory.
2. For glibc, we translate to nl_langinfo_l() calls, because it
offers the same information that way as an extension, and that API is
thread-safe.
3. For macOS/*BSD, use localeconv_l(), which is thread-safe.
4. For everything else, use uselocale() to set the locale for the
thread, and use a big ugly lock to defend against the returned object
being concurrently clobbered. In practice this currently means only
Solaris.
The new call is used in pg_locale.c, replacing calls to setlocale() and
localeconv().
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
Previously NULL nodes were ignored. This could cause issues where the
computed query ID could match for queries where fields that are next to
each other in their Node struct where one field was NULL and the other
non-NULL. For example, the Query struct had distinctClause and sortClause
next to each other. If someone wrote;
SELECT DISTINCT c1 FROM t;
and then;
SELECT c1 FROM t ORDER BY c1;
these would produce the same query ID since, in the first query, we
ignored the NULL sortClause and appended the jumble bytes for the
distictClause. In the latter query, since we did nothing for the NULL
distinctClause then jumble the non-NULL sortClause, and since the node
representation stored is the same in both cases, the query IDs were
identical.
Here we fix this by always accounting for NULL nodes by recording that
we saw a NULL in the jumble buffer. This fixes the issue as the order that
the NULL is recorded isn't the same in the above two queries.
Author: Bykov Ivan <i.bykov@modernsys.ru>
Author: Michael Paquier <michael@paquier.xyz>
Author: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/aafce7966e234372b2ba876c0193f1e9%40localhost.localdomain
Performing AIO using io_uring can be considerably faster than
io_method=worker, particularly when lots of small IOs are issued, as
a) the context-switch overhead for worker based AIO becomes more significant
b) the number of IO workers can become limiting
io_uring, however, is linux specific and requires an additional compile-time
dependency (liburing).
This implementation is fairly simple and there are substantial optimization
opportunities.
The description of the existing AIO_IO_COMPLETION wait event is updated to
make the difference between it and the new AIO_IO_URING_EXECUTION clearer.
Reviewed-by: Noah Misch <noah@leadboat.com>
Reviewed-by: Jakub Wartak <jakub.wartak@enterprisedb.com>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
Discussion: https://postgr.es/m/20210223100344.llw5an2aklengrmn@alap3.anarazel.de
Discussion: https://postgr.es/m/stj36ea6yyhoxtqkhpieia2z4krnam7qyetc57rfezgk4zgapf@gcnactj4z56m
The old naming pattern (mirroring liburing's naming) was inconsistent with
the (not yet introduced) callers. It seems better to get rid of the
inconsistency now than to grow more users of the odd naming.
Reported-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20250326001915.bc.nmisch@google.com
Otherwise the results of e.g. temp table buffer verification errors will not
reach bufmgr.c. Obviously that's not right. Found while expanding the tests
for invalid buffer contents.
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20250326001915.bc.nmisch@google.com
This macro allows dynamically loaded shared libraries (modules) to
provide a wired-in module name and version, and possibly other
compile-time-constant fields in future. This information can be
retrieved with the new pg_get_loaded_modules() function.
This feature is expected to be particularly useful for modules
that do not have any exposed SQL functionality and thus are
not associated with a SQL-level extension object. But even for
modules that do belong to extensions, being able to verify the
actual code version can be useful.
Author: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Yurii Rashkovskii <yrashk@omnigres.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/dd4d1b59-d0fe-49d5-b28f-1e463b68fa32@gmail.com
Due to a conflict in macro names on Windows between <wincrypt.h>
and <openssl/ssl.h> these headers need to be included using a
predictable pattern with an undef to handle that. The GSSAPI
header <gssapi.h> does include <wincrypt.h> which cause problems
with compiling PostgreSQL using MSVC when OpenSSL and GSSAPI are
both enabled in the tree. Rather than fixing piecemeal for each
file including gssapi headers, move the the includes and undef
to a new file which should be used to centralize the logic.
This patch is a reworked version of a patch by Imran Zaheer
proposed earlier in the thread. Once this has proven effective
in master we should look at backporting this as the problem
exist at least since v16.
Author: Daniel Gustafsson <daniel@yesql.se>
Co-authored-by: Imran Zaheer <imran.zhir@gmail.com>
Reported-by: Dave Page <dpage@pgadmin.org>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Discussion: https://postgr.es/m/20240708173204.3f3xjilglx5wuzx6@awork3.anarazel.de
These are useful general-purpose math functions which are included in
POSIX and C99, and are commonly included in other math libraries, so
expose them as SQL-callable functions.
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
Reviewed-by: Stepan Neretin <sncfmgg@gmail.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Dmitry Koval <d.koval@postgrespro.ru>
Reviewed-by: Alexandra Wang <alexandra.wang.oss@gmail.com>
Discussion: https://postgr.es/m/CAEZATCXpGyfjXCirFk9au+FvM0y2Ah+2-0WSJx7MO368ysNUPA@mail.gmail.com
custom_query_jumble (introduced in 5ac462e2b7 as a node field
attribute) is now assigned to the expanded reference name "eref" of
RangeTblEntry, adding in the query jumble computation the non-qualified
aliased relation name, without the list of column names. The relation
OID is removed from the query jumbling.
The effects of this change can be seen in the tests added by
3430215fe3, where pg_stat_statements (PGSS) entries are now grouped
using the relation name, ignoring the relation search_path may point at.
For example, these two relations are different, but are now grouped in a
single PGSS entry as they are assigned the same query ID:
CREATE TABLE foo1.tab (a int);
CREATE TABLE foo2.tab (b int);
SET search_path = 'foo1';
SELECT count(*) FROM tab;
SET search_path = 'foo2';
SELECT count(*) FROM tab;
SELECT count(*) FROM foo1.tab;
SELECT count(*) FROM foo2.tab;
SELECT query, calls FROM pg_stat_statements WHERE query ~ 'FROM tab';
query | calls
--------------------------+-------
SELECT count(*) FROM tab | 4
(1 row)
It is still possible to use an alias in the FROM clause to split these.
This behavior is useful for relations re-created with the same name,
where queries based on such relations would be grouped in the same
PGSS entry. For permanent schemas, it should not really matter in
practice. The main benefit is for workloads that use a lot of temporary
relations, which are usually re-created with the same name continuously.
These can be a heavy source of bloat in PGSS depending on the workload.
Such entries can now be grouped together, improving the user experience.
The original idea from Christoph Berg used catalog lookups to find
temporary relations, something that the query jumble has never done, and
it could cause some performance regressions. The idea to use
RangeTblEntry.eref and the relation name, applying the same rules for
all relations, temporary and not temporary, has been proposed by Tom
Lane. The documentation additions have been suggested by Sami Imseih.
Author: Michael Paquier <michael@paquier.xyz>
Co-authored-by: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Christoph Berg <myon@debian.org>
Reviewed-by: Lukas Fittl <lukas@fittl.com>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Discussion: https://postgr.es/m/Z9iWXKGwkm8RAC93@msg.df7cb.de
This new option instructs pg_upgrade to move the data directories
from the old cluster to the new cluster and then to replace the
catalog files with those generated for the new cluster. This mode
can outperform --link, --clone, --copy, and --copy-file-range,
especially on clusters with many relations.
However, this mode creates many garbage files in the old cluster,
which can prolong the file synchronization step if
--sync-method=syncfs is used. To handle that, we recommend using
--sync-method=fsync with this mode, and pg_upgrade internally uses
"initdb --sync-only --no-sync-data-files" for file synchronization.
pg_upgrade will synchronize the catalog files as they are
transferred. We assume that the database files transferred from
the old cluster were synchronized prior to upgrade.
This mode also complicates reverting to the old cluster, so we
recommend restoring from backup upon failure during or after file
transfer. We did consider teaching pg_upgrade how to generate a
revert script for such failures, but we decided against it due to
the rarity of failing during file transfer, the complexity of
generating the script, and the potential for misusing the script.
The new mode is limited to clusters located in the same file
system. With some effort, we could probably support upgrades
between different file systems, but this mode is unlikely to offer
much benefit if we have to copy the files across file system
boundaries.
It is also limited to upgrades from version 10 or newer. There are
a few known obstacles for using swap mode to upgrade from older
versions. For example, the visibility map format changed in v9.6,
and the sequence tuple format changed in v10. In fact, swap mode
omits the --sequence-data option in its uses of pg_dump and instead
reuses the old cluster's sequence data files. While teaching swap
mode to deal with these kinds of changes is surely possible (and we
may have to deal with similar problems in the future, anyway), it
doesn't seem worth the effort to support upgrades from
long-unsupported versions.
Reviewed-by: Greg Sabino Mullane <htamfids@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/Zyvop-LxLXBLrZil%40nathan
This new option instructs initdb to skip synchronizing any files
in database directories, the database directories themselves, and
the tablespace directories, i.e., everything in the base/
subdirectory and any other tablespace directories. Other files,
such as those in pg_wal/ and pg_xact/, will still be synchronized
unless --no-sync is also specified. --no-sync-data-files is
primarily intended for internal use by tools that separately ensure
the skipped files are synchronized to disk. A follow-up commit
will use this to help optimize pg_upgrade's file transfer step.
The --sync-method=fsync implementation of this option makes use of
a new exclude_dir parameter for walkdir(). When not NULL,
exclude_dir specifies a directory to skip processing. The
--sync-method=syncfs implementation of this option just skips
synchronizing the non-default tablespace directories. This means
that initdb will still synchronize some or all of the database
files, but there's not much we can do about that.
Discussion: https://postgr.es/m/Zyvop-LxLXBLrZil%40nathan
For import and export, use schemaname/relname rather than
regclass.
This is more natural during export, fits with the other arguments
better, and it gives better control over error handling in case we
need to downgrade more errors to warnings.
Also, use text for the argument types for schemaname, relname, and
attname so that casts to "name" are not required.
Author: Corey Huinker <corey.huinker@gmail.com>
Discussion: https://postgr.es/m/CADkLM=ceOSsx_=oe73QQ-BxUFR2Cwqum7-UP_fPe22DBY0NerA@mail.gmail.com
Previously we used pg_int64 in three function prototypes in libpq. It
was added by commit 461ef73f to expose the platform-dependent type used
for int64 in the C89 era. As of commit 962da900 it is defined as
standard int64_t, and the dust seems to have settled.
Let's just use int64_t directly in these three client-facing functions
instead of (yet) another name. We've required C99 and thus <stdint.h>
since PostgreSQL 12, C89 and C++98 compilers are long gone, and client
applications very likely use standard types for their own 64-bit needs.
This also cleans up the obscure placement of a new #include <stdint.h>
directive in postgres_ext.h, required for the new definition. The
typedef was hiding in there for historical reasons, but it doesn't fit
postgres_ext.h's own description of its purpose and there is no evidence
of client applications including postgres_ext.h directly to see it.
Keep a typedef marked deprecated for backward compatibility, but move it
into libpq-fe.h where it was used.
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/CA%2BhUKGKn_EkNNGMY5RzMcKP%2Ba6urT4JF%3DCPhw_zHtQwjvX6P2g%40mail.gmail.com
This option gives the possibility for query jumble to define a custom
routine for the field of a Node, extending support for
custom_query_jumble as a node field attribute. When dealing with
complex node structures, this can be simpler than having to enforce a
custom function across a full node.
Custom functions need to be defined in queryjumblefuncs.c, named as
_jumble${node}_${field}(), and use in input the JumbleState, the node
and its field. The field is not really required if we have the Node,
but it makes custom implementations somewhat easier to think about. The
code generated by gen_node_support.pl uses a macro called
JUMBLE_CUSTOM(), hiding the internals of the logic inside
queryjumblefuncs.c.
This will be used by an upcoming patch manipulating adding a custom
routine into a field of RangeTblEntry, but this facility can become
useful in more cases.
Reviewed-by: Christoph Berg <myon@debian.org>
Discussion: https://postgr.es/m/Z9y43-dRvb4EtxQ0@paquier.xyz
Reduces memory required for hash aggregation by avoiding an allocation
and a pointer in the TupleHashEntryData structure. That structure is
used for all buckets, whether occupied or not, so the savings is
substantial.
Discussion: https://postgr.es/m/AApHDvpN4v3t_sdz4dvrv1Fx_ZPw=twSnxuTEytRYP7LFz5K9A@mail.gmail.com
Reviewed-by: David Rowley <dgrowleyml@gmail.com>
Allows an "extra" argument that allocates extra memory at the end of
the MinimalTuple. This is important for callers that need to store
additional data, but do not want to perform an additional allocation.
Suggested-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAApHDvppeqw2pNM-+ahBOJwq2QmC0hOAGsmCpC89QVmEoOvsdg@mail.gmail.com
The entries aren't freed until the entire hash table is destroyed, so
use the Bump allocator to improve allocation speed, avoid wasting
space on the chunk header, and avoid wasting space due to the
power-of-two allocations.
Discussion: https://postgr.es/m/CAApHDvqv1aNB4cM36FzRwivXrEvBO_LsG_eQ3nqDXTjECaatOQ@mail.gmail.com
Reviewed-by: David Rowley
This field was added in commit 0164a0f9ee to provide a way to
determine whether a storage parameter was explicitly set for the
relation or if it just picked up the default value. In most cases,
this can be accomplished by giving the storage parameter a special
out-of-range default value (e.g., the
autovacuum_vacuum_insert_threshold storage parameter defaults to
-2), but this approach doesn't work in all cases. For example, a
Boolean storage parameter cannot be given an out-of-range default,
so we need another way to discover the source of its value.
Reported-by: "David G. Johnston" <david.g.johnston@gmail.com>
Reviewed-by: "David G. Johnston" <david.g.johnston@gmail.com>
Discussion: https://postgr.es/m/CAKFQuwYKtEUYKS%2B18gRs-xPhn0qOJgM2KGyyWVCODHuVn9F-XQ%40mail.gmail.com
Introduce a new conflict type, multiple_unique_conflicts, to handle cases
where an incoming row during logical replication violates multiple UNIQUE
constraints.
Previously, the apply worker detected and reported only the first
encountered key conflict (insert_exists/update_exists), causing repeated
failures as each constraint violation needs to be handled one by one
making the process slow and error-prone.
With this patch, the apply worker checks all unique constraints upfront
once the first key conflict is detected and reports
multiple_unique_conflicts if multiple violations exist. This allows users
to resolve all conflicts at once by deleting all conflicting tuples rather
than dealing with them individually or skipping the transaction.
In the future, this will also allow us to specify different resolution
handlers for such a conflict type.
Add the stats for this conflict type in pg_stat_subscription_stats.
Author: Nisha Moond <nisha.moond412@gmail.com>
Author: Zhijie Hou <houzj.fnst@fujitsu.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Peter Smith <smithpb2250@gmail.com>
Reviewed-by: Dilip Kumar <dilipbalaut@gmail.com>
Discussion: https://postgr.es/m/CABdArM7FW-_dnthGkg2s0fy1HhUB8C3ELA0gZX1kkbs1ZZoV3Q@mail.gmail.com
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
Add a new scheduling heuristic: don't end the ongoing primitive index
scan immediately (at the point where _bt_advance_array_keys notices that
the next set of matching tuples must be on a later page) if the primscan
already managed to step right/left from its first leaf page. Schedule a
recheck against the next sibling leaf page's finaltup instead.
The new heuristic tends to avoid scenarios where the top-level scan
repeatedly starts and ends primitive index scans that each read only one
leaf page from a group of neighboring leaf pages. Affected top-level
scans will now tend to step forward (or backward) through the index
instead, without wasting cycles on descending the index anew.
The recheck mechanism isn't exactly new. But up until now it has only
been used to deal with edge cases involving high key finaltups with one
or more truncated -inf attributes that _bt_advance_array_keys deemed
"provisionally satisfied" (satisfied for the purposes of allowing the
scan to step onto the next page, subject to recheck once on that page).
The mechanism was added by commit 5bf748b8, which invented the general
concept of primitive scan scheduling. It was later enhanced by commit
79fa7b3b, which taught it about cases involving -inf attributes that
satisfy inequality scan keys required in the opposite-to-scan direction
only (arguably, they should have been covered by the earliest version).
Now the recheck mechanism can be applied based on scan-level heuristics,
which have nothing to do with truncated high keys. Now rechecks might
be performed by _bt_readpage when scanning in _either_ scan direction.
The theory behind the new heuristic is that any primitive scan that
makes it past its first leaf page is one that is already likely to have
arrays whose key values match index tuples that are closely clustered
together in the index. The rules that determine whether we ever get
past the first page are still conservative (that'll still only happen
when pstate.finaltup strongly suggests that it's the right thing to do).
Surviving past the first leaf page is a strong signal in itself.
Preparation for an upcoming patch that will add skip scan optimizations
to nbtree. That'll work by adding skip arrays, which behave similarly
to SAOP arrays, but generate their elements procedurally and on-demand.
Note that this commit isn't specifically concerned with skip arrays; the
scheduling logic doesn't (and won't) condition anything on whether the
scan uses skip arrays, SAOP arrays, or some combination of the two
(which seems like a good general principle for _bt_advance_array_keys).
While the problems that this commit ameliorates are more likely with
skip arrays (at least in practice), SAOP arrays (or those with very
dense, contiguous array elements) are also affected.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/CAH2-Wzkz0wPe6+02kr+hC+JJNKfGtjGTzpG3CFVTQmKwWNrXNw@mail.gmail.com
This commit introduces a new GUC option max_active_replication_origins
to control the maximum number of active replication
origins. Previously, this was controlled by
'max_replication_slots'. Having a separate GUC option provides better
flexibility for setting up subscribers, as they may not require
replication slots (for cascading replication) but always require
replication origins.
Author: Euler Taveira <euler@eulerto.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: vignesh C <vignesh21@gmail.com>
Discussion: https://postgr.es/m/b81db436-8262-4575-b7c4-bc0c1551000b@app.fastmail.com
errdetail_relkind_not_supported() was declared within
EXPOSE_TO_CLIENT_CODE, which is mistaken since that function
isn't available client-side. While relatively harmless,
this isn't good precedent.
Discussion: https://postgr.es/m/1134562.1742507765@sss.pgh.pa.us
StartReadBuffers() reports a short read when it finds a cached block
that ends a range needing I/O by updating the caller's *nblocks. It
doesn't want to have to unpin the trailing hit that it knows the caller
wants, so the v17 version used sleight of hand in the name of
simplicity: it included it in *nblocks as if it were part of the I/O,
but internally tracked the shorter real I/O size in io_buffers_len (now
removed).
This API change "forwards" the delimiting buffer to the next call. It's
still pinned, and still stored in the caller's array, but *nblocks no
longer includes stray buffers that are not really part of the operation.
The expectation is that the caller still wants the rest of the blocks
and will call again starting from that point, and now it can pass the
already pinned buffer back in (or choose not to and release it).
The change is needed for the coming asynchronous I/O version's larger
version of the problem: by definition it must move BM_IO_IN_PROGRESS
negotiation from WaitReadBuffers() to StartReadBuffers(), but it might
already have many buffers pinned before it discovers a need to split an
I/O. (The current synchronous I/O version hides that detail from
callers by looping over smaller reads if required to make all covered
buffers valid in WaitReadBuffers(), so it looks like one operation but
it might occasionally be several under the covers.)
Aside from avoiding unnecessary pin traffic, this will also be important
for later work on out-of-order streams: you can't prioritize data that
is already available right now if that fact is hidden from you.
The new API is natural for read_stream.c (see ed0b87ca). After a short
read it leaves forwarded buffers where they fell in its circular queue
for the continuing call to pick up.
Single-block StartReadBuffer() and traditional ReadBuffer() share code
but are not affected by the change. They don't do multi-block I/O.
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier versions)
Discussion: https://postgr.es/m/CA%2BhUKGK_%3D4CVmMHvsHjOVrK6t4F%3DLBpFzsrr3R%2BaJYN8kcTfWg%40mail.gmail.com
Commit c65bc2e1d1 made it possible for
loadable modules to add EXPLAIN options. Normally, any necessary
validation can be performed by the hook function passed to
RegisterExtensionExplainOption, but if a loadable module wants to sanity
check options against each other, that needs to be done after the entire
options list has been processed. So, add an additional hook for that
purpose.
Author: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: http://postgr.es/m/CAA5RZ0vOcJF91O2e5AQN+V6guMNLMhJx83dxALf-iUZ-hLGO_Q@mail.gmail.com
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
The new GUC extension_control_path specifies a path to look for
extension control files. The default value is $system, which looks in
the compiled-in location, as before.
The path search uses the same code and works in the same way as
dynamic_library_path.
Some use cases of this are: (1) testing extensions during package
builds, (2) installing extensions outside security-restricted
containers like Python.app (on macOS), (3) adding extensions to
PostgreSQL running in a Kubernetes environment using operators such as
CloudNativePG without having to rebuild the base image for each new
extension.
There is also a tweak in Makefile.global so that it is possible to
install extensions using PGXS into an different directory than the
default, using 'make install prefix=/else/where'. This previously
only worked when specifying the subdirectories, like 'make install
datadir=/else/where/share pkglibdir=/else/where/lib', for purely
implementation reasons. (Of course, without the path feature,
installing elsewhere was rarely useful.)
Author: Peter Eisentraut <peter@eisentraut.org>
Co-authored-by: Matheus Alcantara <matheusssilv97@gmail.com>
Reviewed-by: David E. Wheeler <david@justatheory.com>
Reviewed-by: Gabriele Bartolini <gabriele.bartolini@enterprisedb.com>
Reviewed-by: Marco Nenciarini <marco.nenciarini@enterprisedb.com>
Reviewed-by: Niccolò Fei <niccolo.fei@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E7C7BFFB-8857-48D4-A71F-88B359FADCFD@justatheory.com
Commit cbc127917e introduced tracking of unpruned relids to avoid
processing pruned relations, and changed ExecInitModifyTable() to
initialize only unpruned result relations. As a result, MERGE
statements that prune all target partitions can now lead to crashes
or incorrect behavior during execution.
The crash occurs because some executor code paths rely on
ModifyTableState.resultRelInfo[0] being present and initialized,
even when no result relations remain after pruning. For example,
ExecMerge() and ExecMergeNotMatched() use the first resultRelInfo
to determine the appropriate action. Similarly,
ExecInitPartitionInfo() assumes that at least one result relation
exists.
To preserve these assumptions, ExecInitModifyTable() now includes the
first result relation in the initialized result relation list if all
result relations for that ModifyTable were pruned. To enable that,
ExecDoInitialPruning() ensures the first relation is locked if it was
pruned and locking is necessary.
To support this exception to the pruning logic, PlannedStmt now
includes a list of RT indexes identifying the first result relation
of each ModifyTable node in the plan. This allows
ExecDoInitialPruning() to check whether each such relation was
pruned and, if so, lock it if necessary.
Bug: #18830
Reported-by: Robins Tharakan <tharakan@gmail.com>
Diagnozed-by: Tender Wang <tndrwang@gmail.com>
Diagnozed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Co-authored-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Reviewed-by: Tender Wang <tndrwang@gmail.com>
Reviewed-by: Dean Rasheed <dean.a.rasheed@gmail.com>
Discussion: https://postgr.es/m/18830-1f31ea1dc930d444%40postgresql.org
The default of 128kB is unchanged, but the upper limit is changed from
32 blocks to 128 blocks, unless the operating system's IOV_MAX is too
low. Some other RDBMSes seem to cap their multi-block buffer pool I/O
around this number, and it seems useful to allow experimentation.
The concrete change is to our definition of PG_IOV_MAX, which provides
the maximum for io_combine_limit and io_max_combine_limit. It also
affects a couple of other places that work with arrays of struct iovec
or smaller objects on the stack, so we still don't want to use the
system IOV_MAX directly without a clamp: it is not under our control and
likely to be 1024. 128 seems acceptable for our current usage.
For Windows, we can't use real scatter/gather yet, so we continue to
define our own IOV_MAX value of 16 and emulate preadv()/pwritev() with
loops. Someone would need to research the trade-offs of raising that
number.
NB if trying to see this working: you might temporarily need to hack
BAS_BULKREAD to be bigger, since otherwise the obvious way of "a very
big SELECT" is limited by that for now.
Suggested-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/CA%2BhUKG%2B2T9p-%2BzM6Eeou-RAJjTML6eit1qn26f9twznX59qtCA%40mail.gmail.com
