Now that pg_upgrade can carry over most optimizer statistics, we
should recommend using vacuumdb's new --missing-stats-only option
to only analyze relations that are missing statistics.
Reviewed-by: John Naylor <johncnaylorls@gmail.com>
Discussion: https://postgr.es/m/Z5O1bpcwDrMgyrYy%40nathan
This commit adds a new --missing-stats-only option that can be used
with --analyze-only or --analyze-in-stages. When this option is
specified, vacuumdb will analyze a relation if it lacks any
statistics for a column, expression index, or extended statistics
object. This new option is primarily intended for use after
pg_upgrade (since it can now retain most optimizer statistics), but
it might be useful in other situations, too.
Author: Corey Huinker <corey.huinker@gmail.com>
Co-authored-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: John Naylor <johncnaylorls@gmail.com>
Discussion: https://postgr.es/m/Z5O1bpcwDrMgyrYy%40nathan
Presently, each call to vacuum_one_database() queries the catalogs
to retrieve the list of tables to process. A follow-up commit will
add a "missing stats only" feature to --analyze-in-stages, which
requires saving the catalog query results (since tables without
statistics will have them after the first stage). This commit adds
a new parameter to vacuum_one_database() that specifies either a
previously-retrieved list or a place to return the catalog query
results. Note that nothing uses this new parameter yet.
Author: Corey Huinker <corey.huinker@gmail.com>
Co-authored-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: John Naylor <johncnaylorls@gmail.com>
Discussion: https://postgr.es/m/Z5O1bpcwDrMgyrYy%40nathan
pg_stat_statements produces multiple entries for queries like
SELECT something FROM table WHERE col IN (1, 2, 3, ...)
depending on the number of parameters, because every element of
ArrayExpr is individually jumbled. Most of the time that's undesirable,
especially if the list becomes too large.
Fix this by introducing a new GUC query_id_squash_values which modifies
the node jumbling code to only consider the first and last element of a
list of constants, rather than each list element individually. This
affects both the query_id generated by query jumbling, as well as
pg_stat_statements query normalization so that it suppresses printing of
the individual elements of such a list.
The default value is off, meaning the previous behavior is maintained.
Author: Dmitry Dolgov <9erthalion6@gmail.com>
Reviewed-by: Sergey Dudoladov (mysterious, off-list)
Reviewed-by: David Geier <geidav.pg@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
Reviewed-by: Sutou Kouhei <kou@clear-code.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Marcos Pegoraro <marcos@f10.com.br>
Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Reviewed-by: Zhihong Yu <zyu@yugabyte.com>
Tested-by: Yasuo Honda <yasuo.honda@gmail.com>
Tested-by: Sergei Kornilov <sk@zsrv.org>
Tested-by: Maciek Sakrejda <m.sakrejda@gmail.com>
Tested-by: Chengxi Sun <sunchengxi@highgo.com>
Tested-by: Jakub Wartak <jakub.wartak@enterprisedb.com>
Discussion: https://postgr.es/m/CA+q6zcWtUbT_Sxj0V6HY6EZ89uv5wuG5aefpe_9n0Jr3VwntFg@mail.gmail.com
The previous commit introduced the infrastructure to start io_workers. This
commit actually makes the workers execute IOs.
IO workers consume IOs from a shared memory submission queue, run traditional
synchronous system calls, and perform the shared completion handling
immediately. Client code submits most requests by pushing IOs into the
submission queue, and waits (if necessary) using condition variables. Some
IOs cannot be performed in another process due to lack of infrastructure for
reopening the file, and must processed synchronously by the client code when
submitted.
For now the default io_method is changed to "worker". We should re-evaluate
that around beta1, we might want to be careful and set the default to "sync"
for 18.
Reviewed-by: Noah Misch <noah@leadboat.com>
Co-authored-by: Thomas Munro <thomas.munro@gmail.com>
Co-authored-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
Discussion: https://postgr.es/m/20210223100344.llw5an2aklengrmn@alap3.anarazel.de
Discussion: https://postgr.es/m/stj36ea6yyhoxtqkhpieia2z4krnam7qyetc57rfezgk4zgapf@gcnactj4z56m
This commit contains the basic, system-wide, infrastructure for
io_method=worker. It does not yet actually execute IO, this commit just
provides the infrastructure for running IO workers, kept separate for easier
review.
The number of IO workers can be adjusted with a PGC_SIGHUP GUC. Eventually
we'd like to make the number of workers dynamically scale up/down based on the
current "IO load".
To allow the number of IO workers to be increased without a restart, we need
to reserve PGPROC entries for the workers unconditionally. This has been
judged to be worth the cost. If it turns out to be problematic, we can
introduce a PGC_POSTMASTER GUC to control the maximum number.
As io workers might be needed during shutdown, e.g. for AIO during the
shutdown checkpoint, a new PMState phase is added. IO workers are shut down
after the shutdown checkpoint has been performed and walsender/archiver have
shut down, but before the checkpointer itself shuts down. See also
87a6690cc69.
Updates PGSTAT_FILE_FORMAT_ID due to the addition of a new BackendType.
Reviewed-by: Noah Misch <noah@leadboat.com>
Co-authored-by: Thomas Munro <thomas.munro@gmail.com>
Co-authored-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
Discussion: https://postgr.es/m/20210223100344.llw5an2aklengrmn@alap3.anarazel.de
Discussion: https://postgr.es/m/stj36ea6yyhoxtqkhpieia2z4krnam7qyetc57rfezgk4zgapf@gcnactj4z56m
Assorted buildfarm members are complaining about "'process_list' may
be used uninitialized in this function" since f76892c9f, presumably
because they don't trust that the switch case labels are exhaustive.
We can silence that by initializing the variable to NULL. Should
a switch fall-through actually happen, we'll get SIGSEGV at the
first use, which is as good as an Assert.
Since many clients default to the X25519 curve in the TLS handshake,
the fact that the server by defualt doesn't support it cause an extra
roundtrip for each TLS connection. By adding multiple curves, which
is supported since 3d1ef3a15c3eb68da, we can reduce the risk of extra
roundtrips.
Author: Daniel Gustafsson <daniel@yesql.se>
Co-authored-by: Jacob Champion <jacob.champion@enterprisedb.com>
Reported-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Jacob Champion <jacob.champion@enterprisedb.com>
Discussion: https://postgr.es/m/20240616234612.6cslu7nqexquvwj7@awork3.anarazel.de
Specifically, add a per-node hook that is called after the per-node
information has been displayed but before we display children, and a
per-query hook that is called after existing query-level information
is printed. This assumes that extension-added information should
always go at the end rather than the beginning or the middle, but
that seems like an acceptable limitation for simplicity. It also
assumes that extensions will only want to add information, not remove
or reformat existing details; those also seem like acceptable
restrictions, at least for now.
If multiple EXPLAIN extensions are used, the order in which any
additional details are printed is likely to depend on the order in
which the modules are loaded. That seems OK, since the user may
have opinions about the order in which output should appear, and the
extension author can't really know whether their stuff is more or
less important to a particular user than some other extension.
Discussion: http://postgr.es/m/CA+TgmoYSzg58hPuBmei46o8D3SKX+SZoO4K_aGQGwiRzvRApLg@mail.gmail.com
Reviewed-by: Srinath Reddy <srinath2133@gmail.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
get_parallel_object_list() was trying to serve two masters, and it was
doing a bad job at both. In particular, it treated the given user_list
as an output argument, but only sometimes. This was confusing, and the
two paths through it didn't really have all that much in common, so the
complexity wasn't buying us much. Split it in two:
get_parallel_tables_list() handles the straightforward cases for
schemas, databases and tables, takes one list as argument and returns
another list.
A new function get_parallel_tabidx_list() handles the case for indexes.
This takes a list as argument and outputs two lists, just like
get_parallel_object_list used to do, but now the API is clearer (IMO
anyway). Another difference is that accompanying the list of indexes
now we have a list of tables as an OID list rather than a
fully-qualified table name list. This makes some comparisons easier,
and we don't really need the names of the tables, just their OIDs.
(This requires atooid, which requires <stdlib.h>).
Author: Ranier Vilela <ranier.vf@gmail.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/CAEudQArfqr0-s0VVPSEh=0kgOgBJvFNdGW=xSL5rBcr0WDMQYQ@mail.gmail.com
Since its introduction in fc34b0d9de27a, the default
maintenance_io_concurrency has been larger than the default
effective_io_concurrency. maintenance_io_concurrency primarily
controlled prefetching done on behalf of the whole system, for
operations like recovery. Therefore it makes sense for it to have a
value equal to or greater than effective_io_concurrency, which controls
I/O concurrency for reading a relation in a bitmap heap scan.
ff79b5b2ab increased effective_io_concurrency to 16, so we'll increase
maintenance_io_concurrency as well. For now, though, we'll keep the
defaults of effective_io_concurrency and maintenance_io_concurrency
equal to one another (16).
On fast, high IOPs systems, significantly higher values of
maintenance_io_concurrency are observably beneficial [1]. However, such
values would flood low IOPs systems and increase overall system I/O
latency.
It is worth mentioning that since 9256822608f and c3e775e608f,
maintenance_io_concurrency also controls the I/O concurrency of each
vacuum worker. Since many autovacuum workers may be simultaneously
issuing I/Os, we want to keep maintenance_io_concurrency appropriately
conservative.
[1] https://postgr.es/m/c5d52837-6256-0556-ac8c-d6d3d558820a%40enterprisedb.com
Suggested-by: Jakub Wartak <jakub.wartak@enterprisedb.com>
Discussion: https://postgr.es/m/CAKZiRmxdHQaU%2B2Zpe6d%3Dx%3D0vigJ1sfWwwVYLJAf%3Dud_wQ_VcUw%40mail.gmail.com
Modules can use RegisterExtensionExplainOption to register new
EXPLAIN options, and GetExplainExtensionId, GetExplainExtensionState,
and SetExplainExtensionState to store related state inside the
ExplainState object.
Since this substantially increases the amount of code that needs
to handle ExplainState-related tasks, move a few bits of existing
code to a new file explain_state.c and add the rest of this
infrastructure there.
See the comments at the top of explain_state.c for further
explanation of how this mechanism works.
This does not yet provide a way for such such options to do anything
useful. The intention is that we'll add hooks for that purpose in a
separate commit.
Discussion: http://postgr.es/m/CA+TgmoYSzg58hPuBmei46o8D3SKX+SZoO4K_aGQGwiRzvRApLg@mail.gmail.com
Reviewed-by: Srinath Reddy <srinath2133@gmail.com>
Reviewed-by: Andrei Lepikhov <lepihov@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Sami Imseih <samimseih@gmail.com>
We were rejecting non-btree indexes in some cases owing to the
inability to determine the equality operators for other index AMs;
that problem no longer exists, because we can look up the equality
operator using COMPARE_EQ.
Stop rejecting these indexes, but instead rely on all unique indexes
having equality operators. Unique indexes must have equality
operators.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
We were rejecting non-btree indexes in some cases owing to the
inability to determine the equality operators for other index AMs;
that problem no longer exists, because we can look up the equality
operator using COMPARE_EQ. The problem of not knowing the strategy
number for equality in other index AMs is already resolved.
Stop rejecting the indexes upfront, and instead reject any for which
the equality operator lookup fails.
Author: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/E72EAA49-354D-4C2E-8EB9-255197F55330@enterprisedb.com
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
pg_upgrade test 005_char_signedness was leaving files like
delete_old_cluster.sh in the source directory for VPATH and meson
builds. The fix is to change the directory to tmp_check before running
the test.
Reported-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: http://postgr.es/m/CA+TgmoYg5e4oznn0XGoJ3+mceG1qe_JJt34rF2JLwvGS5T1hgQ@mail.gmail.com
In the initial pipeline support for psql added in 41625ab8ea3d, \g was
used as the way to push extended query into an ongoing pipeline. \gx
was blocked.
These two meta-commands have format-related options that can be applied
when fetching a query result (expanded, etc.). As the results of a
pipeline are fetched asynchronously, not at the moment of the
meta-command execution but at the moment of a \getresults or a
\endpipeline, authorizing \g while blocking \gx leads to a confusing
implementation, making one think that psql should be smart enough to
remember the output format options defined from the time when \g or \gx
were executed. Doing so would lead to more code complications when
retrieving a batch of results. There is an extra argument other than
simplicity here: the output format options defined at the point of a
\getresults or a \endpipeline execution should be what affect the output
format for a batch of results.
To avoid any confusion, we have settled to the introduction of a new
meta-command called \sendpipeline, replacing \g when within a pipeline.
An advantage of this design is that it is possible to add new options
specific to pipelines when sending a query buffer, independent of \g
and \gx, should it prove to be necessary.
Most of the changes of this commit happen in the regression tests, where
\g is replaced by \sendpipeline. More tests are added to check that \g
is not allowed.
Per discussion between the author, Daniel Vérité and me.
Author: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com>
Discussion: https://postgr.es/m/ad4b9f1a-f7fe-4ab8-8546-90754726d0be@manitou-mail.org
The main motivations to use AIO in PostgreSQL are:
a) Reduce the time spent waiting for IO by issuing IO sufficiently early.
In a few places we have approximated this using posix_fadvise() based
prefetching, but that is fairly limited (no completion feedback, double the
syscalls, only works with buffered IO, only works on some OSs).
b) Allow to use Direct-I/O (DIO).
DIO can offload most of the work for IO to hardware and thus increase
throughput / decrease CPU utilization, as well as reduce latency. While we
have gained the ability to configure DIO in d4e71df6, it is not yet usable
for real world workloads, as every IO is executed synchronously.
For portability, the new AIO infrastructure allows to implement AIO using
different methods. The choice of the AIO method is controlled by the new
io_method GUC. As of this commit, the only implemented method is "sync",
i.e. AIO is not actually executed asynchronously. The "sync" method exists to
allow to bypass most of the new code initially.
Subsequent commits will introduce additional IO methods, including a
cross-platform method implemented using worker processes and a linux specific
method using io_uring.
To allow different parts of postgres to use AIO, the core AIO infrastructure
does not need to know what kind of files it is operating on. The necessary
behavioral differences for different files are abstracted as "AIO
Targets". One example target would be smgr. For boring portability reasons,
all targets currently need to be added to an array in aio_target.c. This
commit does not implement any AIO targets, just the infrastructure for
them. The smgr target will be added in a later commit.
Completion (and other events) of IOs for one type of file (i.e. one AIO
target) need to be reacted to differently, based on the IO operation and the
callsite. This is made possible by callbacks that can be registered on
IOs. E.g. an smgr read into a local buffer does not need to update the
corresponding BufferDesc (as there is none), but a read into shared buffers
does. This commit does not contain any callbacks, they will be added in
subsequent commits.
For now the AIO infrastructure only understands READV and WRITEV operations,
but it is expected that more operations will be added. E.g. fsync/fdatasync,
flush_range and network operations like send/recv.
As of this commit, nothing uses the AIO infrastructure. Later commits will add
an smgr target, md.c and bufmgr.c callbacks and then finally use AIO for
read_stream.c IO, which, in one fell swoop, will convert all read stream users
to AIO.
The goal is to use AIO in many more places. There are patches to use AIO for
checkpointer and bgwriter that are reasonably close to being ready. There also
are prototypes to use it for WAL, relation extension, backend writes and many
more. Those prototypes were important to ensure the design of the AIO
subsystem is not too limiting (e.g. WAL writes need to happen in critical
sections, which influenced a lot of the design).
A future commit will add an AIO README explaining the AIO architecture and how
to use the AIO subsystem. The README is added later, as it references details
only added in later commits.
Many many more people than the folks named below have contributed with
feedback, work on semi-independent patches etc. E.g. various folks have
contributed patches to use the read stream infrastructure (added by Thomas in
b5a9b18cd0b) in more places. Similarly, a *lot* of folks have contributed to
the CI infrastructure, which I had started to work on to make adding AIO
feasible.
Some of the work by contributors has gone into the "v1" prototype of AIO,
which heavily influenced the current design of the AIO subsystem. None of the
code from that directly survives, but without the prototype, the current
version of the AIO infrastructure would not exist.
Similarly, the reviewers below have not necessarily looked at the current
design or the whole infrastructure, but have provided very valuable input. I
am to blame for problems, not they.
Author: Andres Freund <andres@anarazel.de>
Co-authored-by: Thomas Munro <thomas.munro@gmail.com>
Co-authored-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Co-authored-by: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Noah Misch <noah@leadboat.com>
Reviewed-by: Jakub Wartak <jakub.wartak@enterprisedb.com>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Dmitry Dolgov <9erthalion6@gmail.com>
Reviewed-by: Antonin Houska <ah@cybertec.at>
Discussion: https://postgr.es/m/uvrtrknj4kdytuboidbhwclo4gxhswwcpgadptsjvjqcluzmah%40brqs62irg4dt
Discussion: https://postgr.es/m/20210223100344.llw5an2aklengrmn@alap3.anarazel.de
Discussion: https://postgr.es/m/stj36ea6yyhoxtqkhpieia2z4krnam7qyetc57rfezgk4zgapf@gcnactj4z56m
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
Added tests:
- recovery from running out of unpinned local buffers
- that we don't run out of unpinned buffers due to read stream (only recently
fixed, in 92fc6856cb4)
- temp tables can't be dropped while in use by cursors
Discussion: weskknhckugbdm2yt7sa2uq53xlsax67gcdkac34sanb7qpd3p@hcc2wadao5wy
Discussion: https://postgr.es/m/ge6nsuddurhpmll3xj22vucvqwp4agqz6ndtcf2mhyeydzarst@l75dman5x53p
This is similar to pg_upgrade's --link option, except that here we won't
typically be able to use it for every input file: sometimes we will need
to reconstruct a complete backup from blocks stored in different files.
However, when a whole file does need to be copied, we can use an
optimized copying strategy: see the existing --clone and
--copy-file-range options and the code to use CopyFile() on Windows.
This commit adds a new strategy: add a hard link to an existing file.
Making a hard link doesn't actually copy anything, but it makes sense
for the code to treat it as doing so.
This is useful when the input directories are merely staging directories
that will be removed once the restore is complete. In such cases, there
is no need to actually copy the data, and making a bunch of new hard
links can be very quick. However, it would be quite dangerous to use it
if the input directories might later be reused for any other purpose,
since starting postgres on the output directory would destructively
modify the input directories. For that reason, using this new option
causes pg_combinebackup to emit a warning about the danger involved.
Author: Israel Barth Rubio <barthisrael@gmail.com>
Co-authored-by: Robert Haas <robertmhaas@gmail.com> (cosmetic changes)
Reviewed-by: Vignesh C <vignesh21@gmail.com>
Discussion: http://postgr.es/m/CA+TgmoaEFsYHsMefNaNkU=2SnMRufKE3eVJxvAaX=OWgcnPmPg@mail.gmail.com
Row-level security is mostly referred to as "row security" in
user-facing messages. Commit cd3c45125 introduced one inconsistent
use of "row level security"; make that one match the rest.
Author: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Discussion: https://postgr.es/m/20250317.135305.573764276033358827.horikyota.ntt@gmail.com
This commit addresses some inconsistencies with how the options of some
routines from PostgreSQL/Test/ are written, mainly for init() and
init_from_backup() in Cluster.pm. These are written as unquoted, except
in the locations updated here.
Changes extracted from a larger patch by the same author.
Author: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: https://postgr.es/m/87jz8rzf3h.fsf@wibble.ilmari.org
This commit reshapes the grammar of some commands to apply a more
consistent style across the board, following rules similar to
ce1b0f9da03e:
- Elimination of some pointless used-once variables.
- Use of long options, to self-document better the options used.
- Use of fat commas to link option names and their assigned values,
including redirections, so as perltidy can be tricked to put them
together.
Author: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Discussion: https://postgr.es/m/87jz8rzf3h.fsf@wibble.ilmari.org
This reverts commit b860848232aa, that was added as a prerequisite for
the support of pgstats data flush across checkpoints, linking a pgstats
file to a specific checkpoint redo LSN.
As reported, this is proving to be currently problematic when going
through a pg_upgrade, that does direct manipulations of the control file
in the new cluster. The LSN stored in the pgstats file is not able to
cope with any changes done in the control file by pg_upgrade yet,
causing the pgstats file to be discarded when starting the new cluster
after overriding its redo LSN (one is a `pg_resetwal -l` where the new
cluster's start LSN is bumped by a hardcoded value of 8 segments, see
copy_xact_xlog_xid).
The least painful path going forward is likely going to be a refactor of
the pgstats code so as it is possible to read and write some of its data
with some routines in src/common/, so as pg_upgrade or pg_resetwal are
able to update its data. The main point is that we are going to need a
LSN in the stats file should we make it written at checkpoint time and
not only as part of a shutdown sequence. It is too late to dive into
these details for v18, so let's revert the change, and let's try to
figure out all the details in the next release cycle. The pgstats file
is currently only written as part of a shutdown sequence, and its
contents are still lost on crash, same as older releases.
Bump PGSTAT_FILE_FORMAT_ID.
Reported-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/2563883.1741826489@sss.pgh.pa.us
Add --no-policies option to control row level security policy handling
in dump and restore operations. When this option is used, both CREATE
POLICY commands and ALTER TABLE ... ENABLE ROW LEVEL SECURITY commands
are excluded from dumps and skipped during restores.
This is useful in scenarios where policies need to be redefined in the
target system or when moving data between environments with different
security requirements.
Author: Nikolay Samokhvalov <nik@postgres.ai>
Reviewed-by: Greg Sabino Mullane <htamfids@gmail.com>
Reviewed-by: Jim Jones <jim.jones@uni-muenster.de>
Reviewed-by: newtglobal postgresql_contributors <postgresql_contributors@newtglobalcorp.com>
Discussion: https://postgr.es/m/CAM527d8kG2qPKvbfJ=OYJkT7iRNd623Bk+m-a4ngm+nyHYsHog@mail.gmail.com
47f99a407d introduced a parallel index-level REINDEX. The code was written
assuming that running run_reindex_command() with 'async == true' can schedule
a number of queries for a connection. That's not true, and the second query
sent using run_reindex_command() will wait for the completion of the previous
one.
This commit fixes that by putting REINDEX commands for the same table into a
single query.
Also, this commit removes the 'async' argument from run_reindex_command(),
as only its call always passes 'async == true'.
Reported-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/202503071820.j25zn3lo4hvn%40alvherre.pgsql
Reviewed-by: Álvaro Herrera <alvherre@alvh.no-ip.org>
Backpatch-through: 17
This commit adjusts some code added by e117cfb2f6c6 in the atexit()
callback of pg_createsubscriber.c, in charge of performing post-failure
cleanup actions. The code loops over all the databases specified, and
it is changed here to rely on a single LogicalRepInfo for each database
rather than always using LogicalRepInfos, simplifying its logic.
Author: Peter Smith <smithpb2250@gmail.com>
Discussion: https://postgr.es/m/CAHut+PtdBSVi4iH7BObDVwDNVwOpn+H3fezOBdSTtENx+rhNMw@mail.gmail.com
To initiate IO on a shared buffer we have StartBufferIO(). For temporary table
buffers no similar function exists - likely because the code for that
currently is very simple due to the lack of concurrency.
However, the upcoming AIO support will make it possible to re-encounter a
local buffer, while the buffer already is the target of IO. In that case we
need to wait for already in-progress IO to complete. This commit makes it
easier to add the necessary code, by introducing StartLocalBufferIO().
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_b9anbWzEs5AAF9WCvcEVmgz-1AkHSQ-CLLy-p7WHzvFw@mail.gmail.com
Previously we had two paths implementing writing out temporary table
buffers. For shared buffers, the logic for that is centralized in
FlushBuffer(). Introduce FlushLocalBuffer() to do the same for local buffers.
Besides being a nice cleanup on its own, it also makes an upcoming change
slightly easier.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_b9anbWzEs5AAF9WCvcEVmgz-1AkHSQ-CLLy-p7WHzvFw@mail.gmail.com
Previously TerminateLocalBufferIO() was open-coded in multiple places, which
doesn't seem like a great idea. While TerminateLocalBufferIO() currently is
rather simple, an upcoming patch requires additional code to be added to
TerminateLocalBufferIO(), making this modification particularly worthwhile.
For some reason FlushRelationBuffers() previously cleared BM_JUST_DIRTIED,
even though that's never set for temporary buffers. This is not carried over
as part of this change.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_b9anbWzEs5AAF9WCvcEVmgz-1AkHSQ-CLLy-p7WHzvFw@mail.gmail.com
Previously, there were three copies of this code, two of them
identical. There's no good reason for that.
This change is nice on its own, but the main motivation is the AIO patchset,
which needs to add extra checks the deduplicated code, which of course is
easier if there is only one version.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_b9anbWzEs5AAF9WCvcEVmgz-1AkHSQ-CLLy-p7WHzvFw@mail.gmail.com
If PinLocalBuffer() were to modify the buf_state, the buf_state in
GetLocalVictimBuffer() would be out of date. Currently that does not happen,
as PinLocalBuffer() only modifies the buf_state if adjust_usagecount=true and
GetLocalVictimBuffer() passes false.
However, it's easy to make this not the case anymore - it cost me a few hours
to debug the consequences.
The minimal fix would be to just refetch the buf_state after after calling
PinLocalBuffer(), but the same danger exists in later parts of the
function. Instead, declare buf_state in the narrower scopes and re-read the
state in conditional branches. Besides being safer, it also fits well with
an upcoming set of cleanup patches that move the contents of the conditional
branches in GetLocalVictimBuffer() into helper functions.
I "broke" this in 794f2594479.
Arguably this should be backpatched, but as the relevant functions are not
exported and there is no actual misbehaviour, I chose to not backpatch, at
least for now.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAAKRu_b9anbWzEs5AAF9WCvcEVmgz-1AkHSQ-CLLy-p7WHzvFw@mail.gmail.com
Commit 27bdec06841 uses a loop variable that is not strictly local to
the loop. Perlcritic disapproves, and there's really no reason as the
variable is not used outside the loop.
Per buildfarm animals koel and crake.
Improve performance and reduce table sizes for case mapping.
The main case mapping table stores only 16-bit offsets, which can be
used to look up the mapped code point in any of the case tables (fold,
lower, upper, or title case). Simple case pairs point to the same
offsets.
Generate a function in generate-unicode_case_table.pl that consists of
a nested branches to test for specific codepoint ranges that determine
the offset in the main table.
Other approaches were considered, such as representing these ranges as
another structure (rather than branches in a generated function), or a
different approach such as a radix tree, or perfect hashing. The
author implemented and tested these alternatives and settled on the
generated branches.
Author: Alexander Borisov <lex.borisov@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Discussion: https://postgr.es/m/7cac7e66-9a3b-4e3f-a997-42aa0c401f80%40gmail.com
After pushing the bitmap iterator into table-AM specific code (as part
of making bitmap heap scan use the read stream API in 2b73a8cd33b7),
scan_bitmap_next_block() no longer returns the current block number.
Since scan_bitmap_next_block() isn't returning any relevant information
to bitmap table scan code, it makes more sense to get rid of it.
Now, bitmap table scan code only calls table_scan_bitmap_next_tuple(),
and the heap AM implementation of scan_bitmap_next_block() is a local
helper in heapam_handler.c.
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/flat/CAAKRu_ZwCwWFeL_H3ia26bP2e7HiKLWt0ZmGXPVwPO6uXq0vaA%40mail.gmail.com
Make Bitmap Heap Scan use the read stream API instead of invoking
ReadBuffer() for each block indicated by the bitmap.
The read stream API handles prefetching, so remove all of the explicit
prefetching from bitmap heap scan code.
Now, heap table AM implements a read stream callback which uses the
bitmap iterator to return the next required block to the read stream
code.
Tomas Vondra conducted extensive regression testing of this feature.
Andres Freund, Thomas Munro, and I analyzed regressions and Thomas Munro
patched the read stream API.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Tested-by: Tomas Vondra <tomas@vondra.me>
Tested-by: Andres Freund <andres@anarazel.de>
Tested-by: Thomas Munro <thomas.munro@gmail.com>
Tested-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Discussion: https://postgr.es/m/flat/CAAKRu_ZwCwWFeL_H3ia26bP2e7HiKLWt0ZmGXPVwPO6uXq0vaA%40mail.gmail.com
Remove the TBMIterateResult member from the TBMPrivateIterator and
TBMSharedIterator and make tbm_[shared|private_]iterate() take a
TBMIterateResult as a parameter.
This allows tidbitmap API users to manage multiple TBMIterateResults per
scan. This is required for bitmap heap scan to use the read stream API,
with which there may be multiple I/Os in flight at once, each one with a
TBMIterateResult.
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/d4bb26c9-fe07-439e-ac53-c0e244387e01%40vondra.me
Make the distance control heuristics simpler and more aggressive in
preparation for asynchronous I/O.
The v17 version of read_stream.c made a conservative choice to limit the
look-ahead distance when streaming sequential blocks, because it
couldn't benefit very much from looking ahead further yet. It had a
three-behavior model where only random I/O would rapidly increase the
look-ahead distance, to support read-ahead advice. Sequential I/O would
move it towards the io_combine_limit setting, just enough to build one
full-sized synchronous I/O at a time, and then expect kernel read-ahead
to avoid I/O stalls.
That already left I/O performance on the table with advice-based I/O
concurrency, since sequential blocks could be followed by random jumps,
eg with the proposed streaming Bitmap Heap Scan patch.
It is time to delete the cautious middle option and adjust the distance
based on recent I/O needs only, since asynchronous reads will need to be
started ahead of time whether random or sequential. It is still limited
by io_combine_limit, *_io_concurrency, buffer availability and
strategy ring size, as before.
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier version)
Tested-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKGK_%3D4CVmMHvsHjOVrK6t4F%3DLBpFzsrr3R%2BaJYN8kcTfWg%40mail.gmail.com
read_stream.c tries not to issue read-ahead advice when it thinks the
kernel's own read-ahead should be active, ie when using buffered I/O and
reading sequential blocks. It previously gave up too easily, and issued
advice only for the first read of up to io_combine_limit blocks in a
larger range of sequential blocks after random jump. The following read
could suffer an avoidable I/O stall.
Fix, by continuing to issue advice until the corresponding preadv()
calls catch up with the start of the region we're currently issuing
advice for, if ever. That's when the kernel actually sees the
sequential pattern. Advice is now disabled only when the stream is
entirely sequential as far as we can see in the look-ahead window, or
in other words, when a sequential region is larger than we can cover
with the current io_concurrency and io_combine_limit settings.
While refactoring the advice control logic, also get rid of the
"suppress_advice" argument that was passed around between functions to
skip useless posix_fadvise() calls immediately followed by preadv().
read_stream_start_pending_read() can figure that out, so let's
concentrate knowledge of advice heuristics in fewer places (our goal
being to make advice-based I/O concurrency a legacy mode soon).
The problem cases were revealed by Tomas Vondra's extensive regression
testing with many different disk access patterns using Melanie
Plageman's streaming Bitmap Heap Scan patch, in a battle against the
venerable always-issue-advice-and-always-one-block-at-a-time code.
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier version)
Reported-by: Melanie Plageman <melanieplageman@gmail.com>
Reported-by: Tomas Vondra <tomas@vondra.me>
Reported-by: Andres Freund <andres@anarazel.de>
Tested-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKGK_%3D4CVmMHvsHjOVrK6t4F%3DLBpFzsrr3R%2BaJYN8kcTfWg%40mail.gmail.com
Discussion: https://postgr.es/m/CA%2BhUKGJ3HSWciQCz8ekP1Zn7N213RfA4nbuotQawfpq23%2Bw-5Q%40mail.gmail.com
This commit introduces a new GUC, log_lock_failure, which controls whether
a detailed log message is produced when a lock acquisition fails. Currently,
it only supports logging lock failures caused by SELECT ... NOWAIT.
The log message includes information about all processes holding or
waiting for the lock that couldn't be acquired, helping users analyze and
diagnose the causes of lock failures.
Currently, this option does not log failures from SELECT ... SKIP LOCKED,
as that could generate excessive log messages if many locks are skipped,
causing unnecessary noise.
This mechanism can be extended in the future to support for logging
lock failures from other commands, such as LOCK TABLE ... NOWAIT.
Author: Yuki Seino <seinoyu@oss.nttdata.com>
Co-authored-by: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Jelte Fennema-Nio <postgres@jeltef.nl>
Discussion: https://postgr.es/m/411280a186cc26ef7034e0f2dfe54131@oss.nttdata.com
This commit improves efficiency in FastPathTransferRelationLocks()
and GetLockConflicts(), which iterate over PGPROCs to search for
fast-path locks.
Previously, these functions recalculated the fast-path group during
every loop iteration, even though it remained constant. This update
optimizes the process by calculating the group once and reusing it
throughout the loop.
The functions also now skip empty fast-path groups, avoiding
unnecessary scans of their slots. Additionally, groups belonging to
inactive backends (with pid=0) are always empty, so checking
the group is sufficient to bypass these backends, further enhancing
performance.
Author: Fujii Masao <masao.fujii@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: https://postgr.es/m/07d5fd6a-71f1-4ce8-8602-4cc6883f4bd1@oss.nttdata.com
