CREATE SCHEMA AUTHORIZATION with appended schema elements can lead to
crashes when comparing the schema name of the query with the schemas
used in the qualification of some clauses in the elements' queries.
The origin of the problem is that the transformation routine for the
elements listed in a CREATE SCHEMA query uses as new, expected, schema
name the one listed in CreateSchemaStmt itself. However, depending on
the query, CreateSchemaStmt.schemaname may be NULL, being computed
instead from the role specification of the query given by the
AUTHORIZATION clause, that could be either:
- A user name string, with the new schema name being set to the same
value as the role given.
- Guessed from CURRENT_ROLE, SESSION_ROLE or CURRENT_ROLE, with a new
schema name computed from the security context where CREATE SCHEMA is
running.
Regression tests are added for CREATE SCHEMA with some appended elements
(some of them with schema qualifications), covering also some role
specification patterns.
While on it, this simplifies the context structure used during the
transformation of the elements listed in a CREATE SCHEMA query by
removing the fields for the role specification and the role type. They
were not used, and for the role specification this could be confusing as
the schema name may by extracted from that at the beginning of
CreateSchemaCommand().
This issue exists for a long time, so backpatch down to all the versions
supported.
Reported-by: Song Hongyu
Author: Michael Paquier
Reviewed-by: Richard Guo
Discussion: https://postgr.es/m/17909-f65c12dfc5f0451d@postgresql.org
Backpatch-through: 11
The recently added inclusion of guc.h in smgr.h is not necessary and
introduces more server-related stuff. Removing the directive helps
avoid potential issues with including sgmr.h in frontends.
Author: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Discussion: https://postgr.es/m/20230425.115748.2130383825066921512.horikyota.ntt%40gmail.com
vacuum_defer_cleanup_age was introduced before hot_standby_feedback and
replication slots existed. It is hard to use reasonably - commonly it will
either be set too low (not preventing recovery conflicts, while still causing
some bloat), or too high (causing a lot of bloat). The alternatives do not
have that issue.
That on its own might not be sufficient reason to remove
vacuum_defer_cleanup_age, but it also complicates computation of xid
horizons. See e.g. the bug fixed in be504a3e97. It also is untested.
This commit removes TransactionIdRetreatSafely(), as there are no users
anymore. There might be potential future users, hence noting that here.
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/20230317230930.nhsgk3qfk7f4axls@awork3.anarazel.de
The name of this function suggests that it ought to reparent R/W
expanded objects to be children of the persistent aggcontext, instead
of copying them. In fact it does no such thing, and if you try to
make it do so you will see multiple regression failures. Rename it
to the less-misleading ExecAggCopyTransValue, and add commentary
about why that attractive-sounding optimization won't work. Also
adjust comments at call sites, some of which were describing logic
that has since been moved into ExecAggCopyTransValue.
Discussion: https://postgr.es/m/3004282.1681930251@sss.pgh.pa.us
a9c70b46 added the statistics view pg_stat_io which contained columns
"io_context" and "io_object". Given that the columns are in the
pg_stat_io view, the "io" prefix is somewhat redundant, so remove it.
The code variables referring to these fields are kept unchanged so as
they can keep their context about I/O.
Bump catalog version.
Author: Melanie Plageman
Reviewed-by: Kyotaro Horiguchi, Fabrízio de Royes Mello
Discussion: https://postgr.es/m/CAAKRu_aAQoJWrvT2BYYQvJChFKra_O-5ra3jhzKJZqWsTR1CPQ@mail.gmail.com
Old versions of Solaris and illumos had buffer overrun bugs in their
strxfrm() implementations. The bugs were fixed more than a decade ago
and the relevant releases are long out of vendor support. It's time to
remove the defense added by commit be8b06c3.
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CA+hUKGJ-ZPJwKHVLbqye92-ZXeLoCHu5wJL6L6HhNP7FkJ=meA@mail.gmail.com
Recent enhancements to rmgr desc routines that made the output summarize
certain block data (added by commits 7d8219a4 and 1c453cfd) dealt with
records that lack relevant block data (and so have nothing to give a
more detailed summary of) by testing !DecodedBkpBlock.has_image. As a
result, more detailed descriptions of block data were not output when
wal_consistency_checking was enabled.
This bug affected records with summarizable block data that also
happened to have an FPI that the REDO routine isn't supposed to apply
(FPIs used for consistency checking purposes only). The presence of
such an FPI was incorrectly taken to indicate the absence of block data.
To fix, test DecodedBkpBlock.has_data, not !DecodedBkpBlock.has_image.
This is the exact condition that we care about, not an inexact proxy.
Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-Wzm5Sc9cBg1qWV_cEBfLNJCrW9FjS-SoHVt8FLA7Ldn8yg@mail.gmail.com
_bt_dedup_pass()'s heapRel argument hasn't been needed or used since
commit cf2acaf4dc made deleting any existing LP_DEAD index tuples the
caller's responsibility.
This fixes many spelling mistakes in comments, but a few references to
invalid parameter names, function names and option names too in comments
and also some in string constants
Also, fix an #undef that was undefining the incorrect definition
Author: Alexander Lakhin
Reviewed-by: Justin Pryzby
Discussion: https://postgr.es/m/d5f68d19-c0fc-91a9-118d-7c6a5a3f5fad@gmail.com
The nbtree VACUUM WAL record stores its page offset number payload in
blk 0 (just like the closely related nbtree DELETE WAL record). Commit
ebd551f5 fixed a similar issue with the DELETE WAL record, but missed
this one.
Make sure that function declarations use names that exactly match the
corresponding names from function definitions in a few places. These
inconsistencies were all introduced relatively recently, after the code
base had parameter name mismatches fixed in bulk (see commits starting
with commits 4274dc22 and 035ce1fe).
pg_bsd_indent still has a couple of similar inconsistencies, which I
(pgeoghegan) have left untouched for now.
Like all earlier commits that cleaned up function parameter names, this
commit was written with help from clang-tidy.
This reverts commit 3d03b24c3 (Revert Add support for Kerberos
credential delegation) which was committed on the grounds of concern
about portability, but on further review and discussion, it's clear that
we are better off explicitly requiring MIT Kerberos as that appears to
be the only GSSAPI library currently that's under proper maintenance
and ongoing development. The API used for storing credentials was added
to MIT Kerberos over a decade ago while for the other libraries which
appear to be mainly based on Heimdal, which exists explicitly to be a
re-implementation of MIT Kerberos, the API never made it to a released
version (even though it was added to the Heimdal git repo over 5 years
ago..).
This post-feature-freeze change was approved by the RMT.
Discussion: https://postgr.es/m/ZDDO6jaESKaBgej0%40tamriel.snowman.net
This reverts commit e056c557ae and minor later fixes thereof.
There's a few problems in this new feature -- most notably regarding
pg_upgrade behavior, but others as well. This new feature is not in any
way critical on its own, so instead of scrambling to fix it we revert it
and try again in early 17 with these issues in mind.
Discussion: https://postgr.es/m/3801207.1681057430@sss.pgh.pa.us
Calling fseek() or ftello() on a handle to a non-seeking device such as
a pipe or a communications device is not supported. Unfortunately,
MSVC's flavor of these routines, _fseeki64() and _ftelli64(), do not
return an error when given a pipe as handle. Some of the logic of
pg_dump and restore relies on these routines to check if a handle is
seekable, causing failures when passing the contents of pg_dump to
pg_restore through a pipe, for example.
This commit introduces wrappers for fseeko() and ftello() on MSVC so as
any callers are able to properly detect the cases of non-seekable
handles. This relies mainly on GetFileType(), sharing a bit of code
with the MSVC port for fstat(). The code in charge of getting a file
type is refactored into a new file called win32common.c, shared by
win32stat.c and the new win32fseek.c. It includes the MSVC ports for
fseeko() and ftello().
Like 765f5df, this is backpatched down to 14, where the fstat()
implementation for MSVC is able to understand about files larger than
4GB in size. Using a TAP test for that is proving to be tricky as
IPC::Run handles the pipes by itself, still I have been able to check
the fix manually.
Reported-by: Daniel Watzinger
Author: Juan José Santamaría Flecha, Michael Paquier
Discussion: https://postgr.es/m/CAC+AXB26a4EmxM2suXxPpJaGrqAdxracd7hskLg-zxtPB50h7A@mail.gmail.com
Backpatch-through: 14
Clarify the goals of the recently added guidelines for rmgrdesc authors:
to avoid gratuitous inconsistencies across resource managers, and to
make it reasonably easy to write a reusable custom parser.
Beyond that, the guidelines leave rmgrdesc authors with a significant
amount of leeway. This even includes the leeway to invent custom
conventions (in cases where it's warranted).
Follow-up to commit 7d8219a4.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAH2-WzkbYuvwYKm-Y-72QEh6SPMQcAo9uONv+mR3bMGcu9E_Cg@mail.gmail.com
Make xl_heap_lock's infobits_set field of type uint8, not int8. Using
int8 isn't appropriate given that the field just holds status bits.
This fixes an oversight in commit 0ac5ad5134.
In passing rename the nearby TransactionId field to "xmax" to make
things consistency with related records, such as xl_heap_lock_updated.
Deliberately avoid a bump in XLOG_PAGE_MAGIC. No backpatch, either.
Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-WzkCd3kOS8b7Rfxw7Mh1_6jvX=Nzo-CWR1VBTiOtVZkWHA@mail.gmail.com
We cannot use the generic array_desc approach with per-tuple nbtree
posting list update metadata because array_desc can only deal with fixed
width elements (e.g., page offset numbers). Using array_desc led to
incorrect rmgr descriptions for updates from nbtree DELETE/VACUUM WAL
records.
To fix, add specialized code to describe the update metadata as array
elements in desc output. We now iterate over the update metadata using
an approach that matches related REDO routines.
Also stop showing the updates offset number array separately in nbtree
DELETE/VACUUM desc output. It's redundant information, since the same
page offset numbers appear in the description of each individual update
element. Also make some small tweaks to the way that we format arrays
in all desc routines (not just nbtree desc routines) to make arrays a
little less verbose.
Oversight in commit 1c453cfd, which enhanced the nbtree rmgr desc
routines.
Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-WzkbYuvwYKm-Y-72QEh6SPMQcAo9uONv+mR3bMGcu9E_Cg@mail.gmail.com
This reverts commit 3d4fa227bc.
Per discussion and buildfarm, this depends on APIs that seem to not
be available on at least one platform (NetBSD). Should be certainly
possible to rework to be optional on that platform if necessary but bit
late for that at this point.
Discussion: https://postgr.es/m/3286097.1680922218@sss.pgh.pa.us
Previously, a PostgreSQL-specific callback checked by the regex engine
had a way to trigger a special error code REG_CANCEL if it detected that
the next call to CHECK_FOR_INTERRUPTS() would certainly throw via
ereport().
A later proposed bugfix aims to move some complex logic out of signal
handlers, so that it won't run until the next CHECK_FOR_INTERRUPTS(),
which makes the above design impossible unless we split
CHECK_FOR_INTERRUPTS() into two phases, one to run logic and another to
ereport(). We may develop such a system in the future, but for the
regex code it is no longer necessary.
An earlier commit moved regex memory management over to our
MemoryContext system. Given that the purpose of the two-phase interrupt
checking was to free memory before throwing, something we don't need to
worry about anymore, it seems simpler to inject CHECK_FOR_INTERRUPTS()
directly into cancelation points, and just let it throw.
Since the plan is to keep PostgreSQL-specific concerns separate from the
main regex engine code (with a view to bein able to stay in sync with
other projects), do this with a new macro INTERRUPT(), customizable in
regcustom.h and defaulting to nothing.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CA%2BhUKGK3PGKwcKqzoosamn36YW-fsuTdOPPF1i_rtEO%3DnEYKSg%40mail.gmail.com
Now that our regex engine uses palloc(), it's not necessary to set up a
special memory context callback to free compiled regexes. The regex has
no resources other than the memory that is already going to be freed in
bulk.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CA%2BhUKGK3PGKwcKqzoosamn36YW-fsuTdOPPF1i_rtEO%3DnEYKSg%40mail.gmail.com
Previously, regex_t objects' memory was managed with malloc() and free()
directly. Switch to palloc()-based memory management instead.
Advantages:
* memory used by cached regexes is now visible with MemoryContext
observability tools
* cleanup can be done automatically in certain failure modes
(something that later commits will take advantage of)
* cleanup can be done in bulk
On the downside, there may be more fragmentation (wasted memory) due to
per-regex MemoryContext objects. This is a problem shared with other
cached objects in PostgreSQL and can probably be improved with later
tuning.
Thanks to Noah Misch for suggesting this general approach, which
unblocks later work on interrupts.
Suggested-by: Noah Misch <noah@leadboat.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CA%2BhUKGK3PGKwcKqzoosamn36YW-fsuTdOPPF1i_rtEO%3DnEYKSg%40mail.gmail.com
Unsurprisingly, this requires wal_level = logical to be set on the primary and
standby. The infrastructure added in 26669757b6 ensures that slots are
invalidated if the primary's wal_level is lowered.
Creating a slot on a standby waits for a xl_running_xact record to be
processed. If the primary is idle (and thus not emitting xl_running_xact
records), that can take a while. To make that faster, this commit also
introduces the pg_log_standby_snapshot() function. By executing it on the
primary, completion of slot creation on the standby can be accelerated.
Note that logical decoding on a standby does not itself enforce that required
catalog rows are not removed. The user has to use physical replication slots +
hot_standby_feedback or other measures to prevent that. If catalog rows
required for a slot are removed, the slot is invalidated.
See 6af1793954 for an overall design of logical decoding on a standby.
Bumps catversion, for the addition of the pg_log_standby_snapshot() function.
Author: "Drouvot, Bertrand" <bertranddrouvot.pg@gmail.com>
Author: Andres Freund <andres@anarazel.de> (in an older version)
Author: Amit Khandekar <amitdkhan.pg@gmail.com> (in an older version)
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: FabrÌzio de Royes Mello <fabriziomello@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-By: Robert Haas <robertmhaas@gmail.com>
Physical walsenders can't send data until it's been flushed; logical
walsenders can't decode and send data until it's been applied. On the
standby, the WAL is flushed first, which will only wake up physical
walsenders; and then applied, which will only wake up logical
walsenders.
Previously, all walsenders were awakened when the WAL was flushed. That
was fine for logical walsenders on the primary; but on the standby the
flushed WAL would have been not applied yet, so logical walsenders were
awakened too early.
Per idea from Jeff Davis and Amit Kapila.
Author: "Drouvot, Bertrand" <bertranddrouvot.pg@gmail.com>
Reviewed-By: Jeff Davis <pgsql@j-davis.com>
Reviewed-By: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/CAA4eK1+zO5LUeisabX10c81LU-fWMKO4M9Wyg1cdkbW7Hqh6vQ@mail.gmail.com
During WAL replay on the standby, when a conflict with a logical slot is
identified, invalidate such slots. There are two sources of conflicts:
1) Using the information added in 6af1793954, logical slots are invalidated if
required rows are removed
2) wal_level on the primary server is reduced to below logical
Uses the infrastructure introduced in the prior commit. FIXME: add commit
reference.
Change InvalidatePossiblyObsoleteSlot() to use a recovery conflict to
interrupt use of a slot, if called in the startup process. The new recovery
conflict is added to pg_stat_database_conflicts, as confl_active_logicalslot.
See 6af1793954 for an overall design of logical decoding on a standby.
Bumps catversion for the addition of the pg_stat_database_conflicts column.
Bumps PGSTAT_FILE_FORMAT_ID for the same reason.
Author: "Drouvot, Bertrand" <bertranddrouvot.pg@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Author: Amit Khandekar <amitdkhan.pg@gmail.com> (in an older version)
Reviewed-by: "Drouvot, Bertrand" <bertranddrouvot.pg@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Fabrízio de Royes Mello <fabriziomello@gmail.com>
Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/20230407075009.igg7be27ha2htkbt@awork3.anarazel.de
Needed for logical decoding on a standby. Slots need to be invalidated because
of the horizon if rows required for logical decoding are removed. If the
primary's wal_level is lowered from 'logical', logical slots on the standby
need to be invalidated.
The new invalidation methods will be used in a subsequent commit.
Logical slots that have been invalidated can be identified via the new
pg_replication_slots.conflicting column.
See 6af1793954 for an overall design of logical decoding on a standby.
Bumps catversion for the addition of the new pg_replication_slots column.
Author: "Drouvot, Bertrand" <bertranddrouvot.pg@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Author: Amit Khandekar <amitdkhan.pg@gmail.com> (in an older version)
Reviewed-by: "Drouvot, Bertrand" <bertranddrouvot.pg@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Fabrízio de Royes Mello <fabriziomello@gmail.com>
Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/20230407075009.igg7be27ha2htkbt@awork3.anarazel.de
This is mainly useful because the upcoming logical-decoding-on-standby feature
adds further reasons for invalidating slots, and we don't want to end up with
multiple invalidated_* fields, or check different attributes.
Eventually we should consider not resetting restart_lsn when invalidating a
slot due to max_slot_wal_keep_size. But that's a user visible change, so left
for later.
Increases SLOT_VERSION, due to the changed field (with a different alignment,
no less).
Reviewed-by: "Drouvot, Bertrand" <bertranddrouvot.pg@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/20230407075009.igg7be27ha2htkbt@awork3.anarazel.de
Provide a way to ask the kernel to use O_DIRECT (or local equivalent)
where available for data and WAL files, to avoid or minimize kernel
caching. This hurts performance currently and is not intended for end
users yet. Later proposed work would introduce our own I/O clustering,
read-ahead, etc to replace the facilities the kernel disables with this
option.
The only user-visible change, if the developer-only GUC is not used, is
that this commit also removes the obscure logic that would activate
O_DIRECT for the WAL when wal_sync_method=open_[data]sync and
wal_level=minimal (which also requires max_wal_senders=0). Those are
non-default and unlikely settings, and this behavior wasn't (correctly)
documented. The same effect can be achieved with io_direct=wal.
Author: Thomas Munro <thomas.munro@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKGK1X532hYqJ_MzFWt0n1zt8trz980D79WbjwnT-yYLZpg%40mail.gmail.com
In order to have the option to use O_DIRECT/FILE_FLAG_NO_BUFFERING in a
later commit, we need the addresses of user space buffers to be well
aligned. The exact requirements vary by OS and file system (typically
sectors and/or memory pages). The address alignment size is set to
4096, which is enough for currently known systems: it matches modern
sectors and common memory page size. There is no standard governing
O_DIRECT's requirements so we might eventually have to reconsider this
with more information from the field or future systems.
Aligning I/O buffers on memory pages is also known to improve regular
buffered I/O performance.
Three classes of I/O buffers for regular data pages are adjusted:
(1) Heap buffers are now allocated with the new palloc_aligned() or
MemoryContextAllocAligned() functions introduced by commit 439f6175.
(2) Stack buffers now use a new struct PGIOAlignedBlock to respect
PG_IO_ALIGN_SIZE, if possible with this compiler. (3) The buffer
pool is also aligned in shared memory.
WAL buffers were already aligned on XLOG_BLCKSZ. It's possible for
XLOG_BLCKSZ to be configured smaller than PG_IO_ALIGNED_SIZE and thus
for O_DIRECT WAL writes to fail to be well aligned, but that's a
pre-existing condition and will be addressed by a later commit.
BufFiles are not yet addressed (there's no current plan to use O_DIRECT
for those, but they could potentially get some incidental speedup even
in plain buffered I/O operations through better alignment).
If we can't align stack objects suitably using the compiler extensions
we know about, we disable the use of O_DIRECT by setting PG_O_DIRECT to
0. This avoids the need to consider systems that have O_DIRECT but
can't align stack objects the way we want; such systems could in theory
be supported with more work but we don't currently know of any such
machines, so it's easier to pretend there is no O_DIRECT support
instead. That's an existing and tested class of system.
Add assertions that all buffers passed into smgrread(), smgrwrite() and
smgrextend() are correctly aligned, unless PG_O_DIRECT is 0 (= stack
alignment tricks may be unavailable) or the block size has been set too
small to allow arrays of buffers to be all aligned.
Author: Thomas Munro <thomas.munro@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://postgr.es/m/CA+hUKGK1X532hYqJ_MzFWt0n1zt8trz980D79WbjwnT-yYLZpg@mail.gmail.com
Support GSSAPI/Kerberos credentials being delegated to the server by a
client. With this, a user authenticating to PostgreSQL using Kerberos
(GSSAPI) credentials can choose to delegate their credentials to the
PostgreSQL server (which can choose to accept them, or not), allowing
the server to then use those delegated credentials to connect to
another service, such as with postgres_fdw or dblink or theoretically
any other service which is able to be authenticated using Kerberos.
Both postgres_fdw and dblink are changed to allow non-superuser
password-less connections but only when GSSAPI credentials have been
delegated to the server by the client and GSSAPI is used to
authenticate to the remote system.
Authors: Stephen Frost, Peifeng Qiu
Reviewed-By: David Christensen
Discussion: https://postgr.es/m/CO1PR05MB8023CC2CB575E0FAAD7DF4F8A8E29@CO1PR05MB8023.namprd05.prod.outlook.com
a9c70b46db and 8aaa04b32S added counting of IO operations to a new view,
pg_stat_io. Now, add IO timing for reads, writes, extends, and fsyncs to
pg_stat_io as well.
This combines the tracking for pgBufferUsage with the tracking for pg_stat_io
into a new function pgstat_count_io_op_time(). This should make it a bit
easier to avoid the somewhat costly instr_time conversion done for
pgBufferUsage.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/flat/CAAKRu_ay5iKmnbXZ3DsauViF3eMxu4m1oNnJXqV_HyqYeg55Ww%40mail.gmail.com
Show a detailed description of the page offset number arrays that appear
in certain nbtree WAL records.
Also brings nbtree desc routines in line with the guidelines established
by recent commit 7d8219a4.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-By: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/flat/20230109215842.fktuhesvayno6o4g%40awork3.anarazel.de
Add helper functions that output arrays in a standard format, and use
the functions inside heapdesc routines. This allows tools like
pg_walinspect to show a detailed description of the page offset number
arrays for records like PRUNE and VACUUM (unless there was an FPI).
Also document the conventions that desc routines should follow. Only
the heapdesc routines follow the conventions for now, so they're just
guidelines for the time being.
Based on a suggestion from Andres Freund.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-By: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/flat/20230109215842.fktuhesvayno6o4g%40awork3.anarazel.de
We now create pg_constaint rows for NOT NULL constraints with
contype='n'.
We propagate these constraints during operations such as adding
inheritance relationships, creating and attaching partitions, creating
tables LIKE other tables. We mostly follow the well-known rules of
conislocal and coninhcount that we have for CHECK constraints, with some
adaptations; for example, as opposed to CHECK constraints, we don't
match NOT NULL ones by name when descending a hierarchy to alter it;
instead we match by column number. This means we don't require the
constraint names to be identical across a hierarchy.
For now, we omit them from system catalogs. Maybe this is worth
reconsidering. We don't support NOT VALID nor DEFERRABLE clauses
either; these can be added as separate features later (this patch is
already large and complicated enough.)
This has been very long in the making. The first patch was written by
Bernd Helmle in 2010 to add a new pg_constraint.contype value ('n'),
which I (Álvaro) then hijacked in 2011 and 2012, until that one was
killed by the realization that we ought to use contype='c' instead:
manufactured CHECK constraints. However, later SQL standard
development, as well as nonobvious emergent properties of that design
(mostly, failure to distinguish them from "normal" CHECK constraints as
well as the performance implication of having to test the CHECK
expression) led us to reconsider this choice, so now the current
implementation uses contype='n' again.
In 2016 Vitaly Burovoy also worked on this feature[1] but found no
consensus for his proposed approach, which was claimed to be closer to
the letter of the standard, requiring additional pg_attribute columns to
track the OID of the NOT NULL constraint for that column.
[1] https://postgr.es/m/CAKOSWNkN6HSyatuys8xZxzRCR-KL1OkHS5-b9qd9bf1Rad3PLA@mail.gmail.com
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Author: Bernd Helmle <mailings@oopsware.de>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Discussion: https://postgr.es/m/CACA0E642A0267EDA387AF2B%40%5B172.26.14.62%5D
Discussion: https://postgr.es/m/AANLkTinLXMOEMz+0J29tf1POokKi4XDkWJ6-DDR9BKgU@mail.gmail.com
Discussion: https://postgr.es/m/20110707213401.GA27098@alvh.no-ip.org
Discussion: https://postgr.es/m/1343682669-sup-2532@alvh.no-ip.org
Discussion: https://postgr.es/m/CAKOSWNkN6HSyatuys8xZxzRCR-KL1OkHS5-b9qd9bf1Rad3PLA@mail.gmail.com
Discussion: https://postgr.es/m/20220817181249.q7qvj3okywctra3c@alvherre.pgsql
This commit adds a limit to the size of an XLogRecord at 1020MB, based
on a suggestion by Heikki Linnakangas. This counts for the overhead
needed by the XLogReader when allocating the memory it needs to read a
record in DecodeXLogRecordRequiredSpace(), based on the record size. An
assertion based on that is added to detect that any additions in the
XLogReader facilities would not cause any overflows. If that's ever the
case, the upper bound allowed would need to be adjusted.
Before this, it was possible for an external module to create WAL
records large enough to be assembled but not replayable, causing
failures when replaying such WAL records on standbys. One case
mentioned where this is possible is the in-core function
pg_logical_emit_message() (wrapper for LogLogicalMessage), that allows
to emit WAL records with an arbitrary amount of data potentially higher
than the replay limit of approximately 1GB (limit of a palloc, minus the
overhead needed by a XLogReader).
This commit is a follow-up of ffd1b6b that has added similar protections
for the block-level data. Here, the checks are extended to the whole
record length, mainrdata_len being extended from uint32 to uint64 with
the routines registering buffer and record data still limited to uint32
to minimize the checks when assembling a record. All the error messages
related to overflow checks are improved to provide more context about
the error happening.
Author: Matthias van de Meent
Reviewed-by: Andres Freund, Heikki Linnakangas, Michael Paquier
Discussion: https://postgr.es/m/CAEze2WgGiw+LZt+vHf8tWqB_6VxeLsMeoAuod0N=ij1q17n5pw@mail.gmail.com
1cbbee033 added BUFFER_USAGE_LIMIT to the VACUUM and ANALYZE commands, so
here we permit that option to be specified in vacuumdb.
In passing, adjust the documents for vacuum_buffer_usage_limit and the
BUFFER_USAGE_LIMIT VACUUM option to mention "kB" rather than "KB". Do the
same for the ERROR message in ExecVacuum() and
check_vacuum_buffer_usage_limit(). Without that we might tell a user that
the valid minimum value is 128 KB only to reject that because we accept
only "kB" and not "KB".
Also, add a small reminder comment in vacuum.h to try to trigger the
memory of anyone adding new fields to VacuumParams that they might want to
consider if vacuumdb needs to grow a new option too.
Author: Melanie Plageman
Reviewed-by: Justin Pryzby
Reviewed-by: David Rowley
Discussion: https://postgr.es/m/ZAzTg3iEnubscvbf@telsasoft.com
While we already had some form of bulk extension for relations, it was fairly
limited. It only amortized the cost of acquiring the extension lock, the
relation itself was still extended one-by-one. Bulk extension was also solely
triggered by contention, not by the amount of data inserted.
To address this, use ExtendBufferedRelBy(), introduced in 31966b151e, to
extend the relation. We try to extend the relation by multiple blocks in two
situations:
1) The caller tells RelationGetBufferForTuple() that it will need multiple
pages. For now that's only used by heap_multi_insert(), see commit FIXME.
2) If there is contention on the extension lock, use the number of waiters for
the lock as a multiplier for the number of blocks to extend by. This is
similar to what we already did. Previously we additionally multiplied the
numbers of waiters by 20, but with the new relation extension
infrastructure I could not see a benefit in doing so.
Using the freespacemap to provide empty pages can cause significant
contention, and adds measurable overhead, even if there is no contention. To
reduce that, remember the blocks the relation was extended by in the
BulkInsertState, in the extending backend. In case 1) from above, the blocks
the extending backend needs are not entered into the FSM, as we know that we
will need those blocks.
One complication with using the FSM to record empty pages, is that we need to
insert blocks into the FSM, when we already hold a buffer content lock. To
avoid doing IO while holding a content lock, release the content lock before
recording free space. Currently that opens a small window in which another
backend could fill the block, if a concurrent VACUUM records the free
space. If that happens, we retry, similar to the already existing case when
otherBuffer is provided. In the future it might be worth closing the race by
preventing VACUUM from recording the space in newly extended pages.
This change provides very significant wins (3x at 16 clients, on my
workstation) for concurrent COPY into a single relation. Even single threaded
COPY is measurably faster, primarily due to not dirtying pages while
extending, if supported by the operating system (see commit 4d330a61bb). Even
single-row INSERTs benefit, although to a much smaller degree, as the relation
extension lock rarely is the primary bottleneck.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/20221029025420.eplyow6k7tgu6he3@awork3.anarazel.de
Add new options to the VACUUM and ANALYZE commands called
BUFFER_USAGE_LIMIT to allow users more control over how large to make the
buffer access strategy that is used to limit the usage of buffers in
shared buffers. Larger rings can allow VACUUM to run more quickly but
have the drawback of VACUUM possibly evicting more buffers from shared
buffers that might be useful for other queries running on the database.
Here we also add a new GUC named vacuum_buffer_usage_limit which controls
how large to make the access strategy when it's not specified in the
VACUUM/ANALYZE command. This defaults to 256KB, which is the same size as
the access strategy was prior to this change. This setting also
controls how large to make the buffer access strategy for autovacuum.
Per idea by Andres Freund.
Author: Melanie Plageman
Reviewed-by: David Rowley
Reviewed-by: Andres Freund
Reviewed-by: Justin Pryzby
Reviewed-by: Bharath Rupireddy
Discussion: https://postgr.es/m/20230111182720.ejifsclfwymw2reb@awork3.anarazel.de
A future commit will use this information to determine how aggressively to
extend the relation by. In heap_multi_insert() we know accurately how many
pages we need once we need to extend the relation, providing an accurate lower
bound for how much to extend.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/20221029025420.eplyow6k7tgu6he3@awork3.anarazel.de
Allow autovacuum to reload the config file more often so that cost-based
delay parameters can take effect while VACUUMing a relation. Previously,
autovacuum workers only reloaded the config file once per relation
vacuumed, so config changes could not take effect until beginning to
vacuum the next table.
Now, check if a reload is pending roughly once per block, when checking
if we need to delay.
In order for autovacuum workers to safely update their own cost delay
and cost limit parameters without impacting performance, we had to
rethink when and how these values were accessed.
Previously, an autovacuum worker's wi_cost_limit was set only at the
beginning of vacuuming a table, after reloading the config file.
Therefore, at the time that autovac_balance_cost() was called, workers
vacuuming tables with no cost-related storage parameters could still
have different values for their wi_cost_limit_base and wi_cost_delay.
Now that the cost parameters can be updated while vacuuming a table,
workers will (within some margin of error) have no reason to have
different values for cost limit and cost delay (in the absence of
cost-related storage parameters). This removes the rationale for keeping
cost limit and cost delay in shared memory. Balancing the cost limit
requires only the number of active autovacuum workers vacuuming a table
with no cost-based storage parameters.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAAKRu_ZngzqnEODc7LmS1NH04Kt6Y9huSjz5pp7%2BDXhrjDA0gw%40mail.gmail.com
Vacuum code run both by autovacuum workers and a backend doing
VACUUM/ANALYZE previously inspected VacuumCostLimit and VacuumCostDelay,
which are the global variables backing the GUCs vacuum_cost_limit and
vacuum_cost_delay.
Autovacuum workers needed to override these variables with their
own values, derived from autovacuum_vacuum_cost_limit and
autovacuum_vacuum_cost_delay and worker cost limit balancing logic.
This led to confusing code which, in some cases, both derived and
set a new value of VacuumCostLimit from VacuumCostLimit.
In preparation for refreshing these GUC values more often, introduce
new, independent global variables and add a function to update them
using the GUCs and existing logic.
Per suggestion by Kyotaro Horiguchi
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAAKRu_ZngzqnEODc7LmS1NH04Kt6Y9huSjz5pp7%2BDXhrjDA0gw%40mail.gmail.com
While vacuuming a table in failsafe mode, VacuumCostActive should
not be re-enabled. This currently isn't a problem because vacuum
cost parameters are only refreshed in between vacuuming tables and
failsafe status is reset for every table.
In preparation for allowing vacuum cost parameters to be updated
more frequently, elevate LVRelState->failsafe_active to a global,
VacuumFailsafeActive, which will be checked when determining whether
or not to re-enable vacuum cost-related delays.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAAKRu_ZngzqnEODc7LmS1NH04Kt6Y9huSjz5pp7%2BDXhrjDA0gw%40mail.gmail.com
zstd compression supports a special mode for finding matched in distant
past, which may result in better compression ratio, at the expense of
using more memory (the window size is 128MB).
To enable this optional mode, use the "long" keyword when specifying the
compression method (--compress=zstd:long).
Author: Justin Pryzby
Reviewed-by: Tomas Vondra, Jacob Champion
Discussion: https://postgr.es/m/20230224191840.GD1653@telsasoft.com
Discussion: https://postgr.es/m/20220327205020.GM28503@telsasoft.com
vacuum() is used for both the VACUUM command and for autovacuum. There
were many prechecks being done inside vacuum() that were just not relevant
to autovacuum. Let's move the bulk of these into ExecVacuum() so that
they're only executed when running the VACUUM command. This removes a
small amount of overhead when autovacuum vacuums a table.
While we are at it, allocate VACUUM's BufferAccessStrategy in ExecVacuum()
and pass it into vacuum() instead of expecting vacuum() to make it if it's
not already made by the calling function. To make this work, we need to
create the vacuum memory context slightly earlier, so we now need to pass
that down to vacuum() so that it's available for use in other memory
allocations.
Author: Melanie Plageman
Reviewed-by: David Rowley
Discussion: https://postgr.es/m/20230405211534.4skgskbilnxqrmxg@awork3.anarazel.de
pg_stat_statements relies on EState->es_processed to count the number of
rows processed by ExecutorRun(). This proves to be a problem under the
extended query protocol when the result of a query is fetched through
more than one call of ExecutorRun(), as es_processed is reset each time
ExecutorRun() is called. This causes pg_stat_statements to report the
number of rows calculated in the last execute fetch, rather than the
global sum of all the rows processed.
As pquery.c tells, this is a problem when a portal does not use
holdStore. For example, DMLs with RETURNING would report a correct
tuple count as these do one execution cycle when the query is first
executed to fill in the portal's store with one ExecutorRun(), feeding
on the portal's store for each follow-up execute fetch depending on the
fetch size requested by the client.
The fix proposed for this issue is simple with the addition of an extra
counter in EState that's preserved across multiple ExecutorRun() calls,
incremented with the value calculated in es_processed. This approach is
not back-patchable, unfortunately.
Note that libpq does not currently give any way to control the fetch
size when using the extended v3 protocol, meaning that in-core testing
is not possible yet. This issue can be easily verified with the JDBC
driver, though, with *autocommit disabled*. Hence, having in-core tests
requires more features, left for future discussion:
- At least two new libpq routines splitting PQsendQueryGuts(), one for
the bind/describe and a second for a series of execute fetches with a
custom fetch size, likely in a fashion similar to what JDBC does.
- A psql meta-command for the execute phase. This part is not strictly
mandatory, still it could be handy.
Reported-by: Andrew Dunstan (original discovery by Simon Siggs)
Author: Sami Imseih
Reviewed-by: Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/EBE6C507-9EB6-4142-9E4D-38B1673363A7@amazon.com
Discussion: https://postgr.es/m/c90890e7-9c89-c34f-d3c5-d5c763a34bd8@dunslane.net
The primary bottlenecks for relation extension are:
1) The extension lock is held while acquiring a victim buffer for the new
page. Acquiring a victim buffer can require writing out the old page
contents including possibly needing to flush WAL.
2) When extending via ReadBuffer() et al, we write a zero page during the
extension, and then later write out the actual page contents. This can
nearly double the write rate.
3) The existing bulk relation extension infrastructure in hio.c just amortized
the cost of acquiring the relation extension lock, but none of the other
costs.
Unfortunately 1) cannot currently be addressed in a central manner as the
callers to ReadBuffer() need to acquire the extension lock. To address that,
this this commit moves the responsibility for acquiring the extension lock
into bufmgr.c functions. That allows to acquire the relation extension lock
for just the required time. This will also allow us to improve relation
extension further, without changing callers.
The reason we write all-zeroes pages during relation extension is that we hope
to get ENOSPC errors earlier that way (largely works, except for CoW
filesystems). It is easier to handle out-of-space errors gracefully if the
page doesn't yet contain actual tuples. This commit addresses 2), by using the
recently introduced smgrzeroextend(), which extends the relation, without
dirtying the kernel page cache for all the extended pages.
To address 3), this commit introduces a function to extend a relation by
multiple blocks at a time.
There are three new exposed functions: ExtendBufferedRel() for extending the
relation by a single block, ExtendBufferedRelBy() to extend a relation by
multiple blocks at once, and ExtendBufferedRelTo() for extending a relation up
to a certain size.
To avoid duplicating code between ReadBuffer(P_NEW) and the new functions,
ReadBuffer(P_NEW) now implements relation extension with
ExtendBufferedRel(), using a flag to tell ExtendBufferedRel() that the
relation lock is already held.
Note that this commit does not yet lead to a meaningful performance or
scalability improvement - for that uses of ReadBuffer(P_NEW) will need to be
converted to ExtendBuffered*(), which will be done in subsequent commits.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/20221029025420.eplyow6k7tgu6he3@awork3.anarazel.de
Michael Paquier
Thomas Munro
Andres Freund
Tom Lane
Peter Geoghegan
David Rowley
Stephen Frost
Alvaro Herrera
Daniel Gustafsson
Tomas Vondra