wal_compression gains a new value, "zstd", to allow the compression of
full-page images using the compression method of the same name.
Compression is done using the default level recommended by the library,
as of ZSTD_CLEVEL_DEFAULT = 3. Some benchmarking has shown that it
could make sense to use a level lower for the FPI compression, like 1 or
2, as the compression rate did not change much with a bit less CPU
consumed, but any tests done would only cover few scenarios so it is
hard to come to a clear conclusion. Anyway, there is no reason to not
use the default level instead, which is the level recommended by the
library so it should be fine for most cases.
zstd outclasses easily pglz, and is better than LZ4 where one wants to
have more compression at the cost of extra CPU but both are good enough
in their own scenarios, so the choice between one or the other of these
comes to a study of the workload patterns and the schema involved,
mainly.
This commit relies heavily on 4035cd5, that reshaped the code creating
and restoring full-page writes to be aware of the compression type,
making this integration straight-forward.
This patch borrows some early work from Andrey Borodin, though the patch
got a complete rewrite.
Author: Justin Pryzby
Discussion: https://postgr.es/m/20220222231948.GJ9008@telsasoft.com
Add ability to scan all entries sequentially to dshash. The interface is
similar but a bit different both from that of dynahash and simple dshash
search functions. The most significant differences is that dshash's interfac
always needs a call to dshash_seq_term when scan ends. Another is
locking. Dshash holds partition lock when returning an entry,
dshash_seq_next() also holds lock when returning an entry but callers
shouldn't release it, since the lock is essential to continue a scan. The
seqscan interface allows entry deletion while a scan is in progress using
dshash_delete_current().
Reviewed-By: Andres Freund <andres@anarazel.de>
Author: Kyotaro Horiguchi <horikyoga.ntt@gmail.com>
Both client-side compression and server-side compression are now
supported for zstd. In addition, a backup compressed by the server
using zstd can now be decompressed by the client in order to
accommodate the use of -Fp.
Jeevan Ladhe, with some edits by me.
Discussion: http://postgr.es/m/CA+Tgmobyzfbz=gyze2_LL1ZumZunmaEKbHQxjrFkOR7APZGu-g@mail.gmail.com
This new function extracts common code from PrepareQuery() and
exec_parse_message(). It is then exactly analogous to the existing
pg_analyze_and_rewrite_fixedparams() and
pg_analyze_and_rewrite_withcb().
To unify these two code paths, this makes PrepareQuery() now subject
to log_parser_stats. Also, both paths now invoke
TRACE_POSTGRESQL_QUERY_REWRITE_START(). PrepareQuery() no longer
checks whether a utility statement was specified. The grammar doesn't
allow that anyway, and exec_parse_message() supports it, so
restricting it doesn't seem necessary.
This also adds QueryEnvironment support to the *varparams functions,
for consistency with its cousins, even though it is not used right
now.
Reviewed-by: Nathan Bossart <bossartn@amazon.com>
Discussion: https://www.postgresql.org/message-id/flat/c67ce276-52b4-0239-dc0e-39875bf81840@enterprisedb.com
Set-returning functions that use the Materialize mode, creating a
tuplestore to include all the tuples returned in a set rather than doing
so in multiple calls, use roughly the same set of steps to prepare
ReturnSetInfo for this job:
- Check if ReturnSetInfo supports returning a tuplestore and if the
materialize mode is enabled.
- Create a tuplestore for all the tuples part of the returned set in the
per-query memory context, stored in ReturnSetInfo->setResult.
- Build a tuple descriptor mostly from get_call_result_type(), then
stored in ReturnSetInfo->setDesc. Note that there are some cases where
the SRF's tuple descriptor has to be the one specified by the function
caller.
This refactoring is done so as there are (well, should be) no behavior
changes in any of the in-core functions refactored, and the centralized
function that checks and sets up the function's ReturnSetInfo can be
controlled with a set of bits32 options. Two of them prove to be
necessary now:
- SRF_SINGLE_USE_EXPECTED to use expectedDesc as tuple descriptor, as
expected by the function's caller.
- SRF_SINGLE_BLESS to validate the tuple descriptor for the SRF.
The same initialization pattern is simplified in 28 places per my
count as of src/backend/, shaving up to ~900 lines of code. These
mostly come from the removal of the per-query initializations and the
sanity checks now grouped in a single location. There are more
locations that could be simplified in contrib/, that are left for a
follow-up cleanup.
fcc2817, 07daca5 and d61a361 have prepared the areas of the code related
to this change, to ease this refactoring.
Author: Melanie Plageman, Michael Paquier
Reviewed-by: Álvaro Herrera, Justin Pryzby
Discussion: https://postgr.es/m/CAAKRu_azyd1Z3W_r7Ou4sorTjRCs+PxeHw1CWJeXKofkE6TuZg@mail.gmail.com
There are three parallel ways to call parse/analyze: with fixed
parameters, with variable parameters, and by supplying your own parser
callback. Some of the involved functions were confusingly named and
made this API structure more confusing. This patch renames some
functions to make this clearer:
parse_analyze() -> parse_analyze_fixedparams()
pg_analyze_and_rewrite() -> pg_analyze_and_rewrite_fixedparams()
(Otherwise one might think this variant doesn't accept parameters, but
in fact all three ways accept parameters.)
pg_analyze_and_rewrite_params() -> pg_analyze_and_rewrite_withcb()
(Before, and also when considering pg_analyze_and_rewrite(), one might
think this is the only way to pass parameters. Moreover, the parser
callback doesn't necessarily need to parse only parameters, it's just
one of the things it could do.)
parse_fixed_parameters() -> setup_parse_fixed_parameters()
parse_variable_parameters() -> setup_parse_variable_parameters()
(These functions don't actually do any parsing, they just set up
callbacks to use during parsing later.)
This patch also adds some const decorations to the fixed-parameters
API, so the distinction from the variable-parameters API is more
clear.
Reviewed-by: Nathan Bossart <bossartn@amazon.com>
Discussion: https://www.postgresql.org/message-id/flat/c67ce276-52b4-0239-dc0e-39875bf81840@enterprisedb.com
There's no visible point in casting the result of a comparison to
bool, because it already is that, at least on C99 compilers.
I see no point in these assertions that a pointer we're about to
dereference isn't null, either. If it is, the resulting SIGSEGV
will notify us of the problem just fine.
Noted while reviewing Zhihong Yu's patch. This is basically
cosmetic, so no need for back-patch.
Discussion: https://postgr.es/m/CALNJ-vT9r0DSsAOw9OXVJFxLENoVS_68kJ5x0p44atoYH+H4dg@mail.gmail.com
This macro cast the result to BlockNumber after shifting, not before,
which is the wrong thing. Per the C spec, the uint16 fields would
promote to int not unsigned int, so that (for 32-bit int) the shift
potentially shifts a nonzero bit into the sign position. I doubt
there are any production systems where this would actually end with
the wrong answer, but it is undefined behavior per the C spec, and
clang's -fsanitize=undefined option reputedly warns about it on some
platforms. (I can't reproduce that right now, but the code is
undeniably wrong per spec.) It's easy to fix by casting to
BlockNumber (uint32) in the proper places.
It's been wrong for ages, so back-patch to all supported branches.
Report and patch by Zhihong Yu (cosmetic tweaking by me)
Discussion: https://postgr.es/m/CALNJ-vT9r0DSsAOw9OXVJFxLENoVS_68kJ5x0p44atoYH+H4dg@mail.gmail.com
This function has been incorrectly marked as a set-returning function
with prorows (estimated number of rows) set to 1 since its creation in
7117685, that introduced non-exclusive backups. There is no need for
that as the function is designed to return only one tuple.
This commit fixes the catalog definition of pg_stop_backup_v2() so as it
is not marked as proretset anymore, with prorows set to 0. This
simplifies its internals by removing one tuplestore (used for one single
record anyway) and by removing all the checks related to a set-returning
function.
Issue found during my quest to simplify some of the logic used in
in-core system functions.
Bump catalog version.
Reviewed-by: Aleksander Alekseev, Kyotaro Horiguchi
Discussion: https://postgr.es/m/Yh8guT78f1Ercfzw@paquier.xyz
It was decided (refer to the Discussion link below) that the stats
collector is not an appropriate place to store the error information of
subscription workers.
This patch changes the pg_stat_subscription_workers view (introduced by
commit 8d74fc96db) so that it stores only statistics counters:
apply_error_count and sync_error_count, and has one entry for
each subscription. The removed error information such as error-XID and
the error message would be stored in another way in the future which is
more reliable and persistent.
After removing these error details, there is no longer any relation
information, so the subscription statistics are now a cluster-wide
statistics.
The patch also changes the view name to pg_stat_subscription_stats since
the word "worker" is an implementation detail that we use one worker for
one tablesync and one apply.
Author: Masahiko Sawada, based on suggestions by Andres Freund
Reviewed-by: Peter Smith, Haiying Tang, Takamichi Osumi, Amit Kapila
Discussion: https://postgr.es/m/20220125063131.4cmvsxbz2tdg6g65@alap3.anarazel.de
This is pretty queasy-making on general principles, and the more so
once you notice that CommitTransactionCommand() is actually stomping
on the values saved by _SPI_commit(). It's okay as long as the
active values didn't change during HoldPinnedPortals(); but that's
a larger assumption than I think we want to make, especially since
the fix is so simple.
Discussion: https://postgr.es/m/1533956.1645731245@sss.pgh.pa.us
SPI_commit previously left it up to the caller to recover from any error
occurring during commit. Since that's complicated and requires use of
low-level xact.c facilities, it's not too surprising that no caller got
it right. Let's move the responsibility for cleanup into spi.c. Doing
that requires redefining SPI_commit as starting a new transaction, so
that it becomes equivalent to SPI_commit_and_chain except that you get
default transaction characteristics instead of preserving the prior
transaction's characteristics. We can make this pretty transparent
API-wise by redefining SPI_start_transaction() as a no-op. Callers
that expect to do something in between might be surprised, but
available evidence is that no callers do so.
Having made that API redefinition, we can fix this mess by having
SPI_commit[_and_chain] trap errors and start a new, clean transaction
before re-throwing the error. Likewise for SPI_rollback[_and_chain].
Some cleanup is also needed in AtEOXact_SPI, which was nowhere near
smart enough to deal with SPI contexts nested inside a committing
context.
While plperl and pltcl need no changes beyond removing their now-useless
SPI_start_transaction() calls, plpython needs some more work because it
hadn't gotten the memo about catching commit/rollback errors in the
first place. Such an error resulted in longjmp'ing out of the Python
interpreter, which leaks Python stack entries at present and is reported
to crash Python 3.11 altogether. Add the missing logic to catch such
errors and convert them into Python exceptions.
We are probably going to have to back-patch this once Python 3.11 ships,
but it's a sufficiently basic change that I'm a bit nervous about doing
so immediately. Let's let it bake awhile in HEAD first.
Peter Eisentraut and Tom Lane
Discussion: https://postgr.es/m/3375ffd8-d71c-2565-e348-a597d6e739e3@enterprisedb.com
Discussion: https://postgr.es/m/17416-ed8fe5d7213d6c25@postgresql.org
See also afdeff10526. Failures after that commit provided a few more hints,
but not yet enough to understand what's going on.
In 019_replslot_limit.pl shut down nodes with fast instead of immediate mode
if we observe the failure mode. That should tell us whether the failures we're
observing are just a timing issue under high load. PGCTLTIMEOUT should prevent
buildfarm animals from hanging endlessly.
Also adds a bit more logging to replication slot drop and ShutdownPostgres().
Discussion: https://postgr.es/m/20220225192941.hqnvefgdzaro6gzg@alap3.anarazel.de
The buffer argument hasn't been used since the function was first added
by commit bbb6e559c4. The sibling heap_prepare_freeze_tuple function
doesn't have such an argument either. Remove it.
This feature adds row filtering for publication tables. When a publication
is defined or modified, an optional WHERE clause can be specified. Rows
that don't satisfy this WHERE clause will be filtered out. This allows a
set of tables to be partially replicated. The row filter is per table. A
new row filter can be added simply by specifying a WHERE clause after the
table name. The WHERE clause must be enclosed by parentheses.
The row filter WHERE clause for a table added to a publication that
publishes UPDATE and/or DELETE operations must contain only columns that
are covered by REPLICA IDENTITY. The row filter WHERE clause for a table
added to a publication that publishes INSERT can use any column. If the
row filter evaluates to NULL, it is regarded as "false". The WHERE clause
only allows simple expressions that don't have user-defined functions,
user-defined operators, user-defined types, user-defined collations,
non-immutable built-in functions, or references to system columns. These
restrictions could be addressed in the future.
If you choose to do the initial table synchronization, only data that
satisfies the row filters is copied to the subscriber. If the subscription
has several publications in which a table has been published with
different WHERE clauses, rows that satisfy ANY of the expressions will be
copied. If a subscriber is a pre-15 version, the initial table
synchronization won't use row filters even if they are defined in the
publisher.
The row filters are applied before publishing the changes. If the
subscription has several publications in which the same table has been
published with different filters (for the same publish operation), those
expressions get OR'ed together so that rows satisfying any of the
expressions will be replicated.
This means all the other filters become redundant if (a) one of the
publications have no filter at all, (b) one of the publications was
created using FOR ALL TABLES, (c) one of the publications was created
using FOR ALL TABLES IN SCHEMA and the table belongs to that same schema.
If your publication contains a partitioned table, the publication
parameter publish_via_partition_root determines if it uses the partition's
row filter (if the parameter is false, the default) or the root
partitioned table's row filter.
Psql commands \dRp+ and \d <table-name> will display any row filters.
Author: Hou Zhijie, Euler Taveira, Peter Smith, Ajin Cherian
Reviewed-by: Greg Nancarrow, Haiying Tang, Amit Kapila, Tomas Vondra, Dilip Kumar, Vignesh C, Alvaro Herrera, Andres Freund, Wei Wang
Discussion: https://www.postgresql.org/message-id/flat/CAHE3wggb715X%2BmK_DitLXF25B%3DjE6xyNCH4YOwM860JR7HarGQ%40mail.gmail.com
"regress" is a new mode added to compute_query_id aimed at facilitating
regression testing when a module computing query IDs is loaded into the
backend, like pg_stat_statements. It works the same way as "auto",
meaning that query IDs are computed if a module enables it, except that
query IDs are hidden in EXPLAIN outputs to ensure regression output
stability.
Like any GUCs of the kind (force_parallel_mode, etc.), this new
configuration can be added to an instance's postgresql.conf, or just
passed down with PGOPTIONS at command level. compute_query_id uses an
enum for its set of option values, meaning that this addition ensures
ABI compatibility.
Using this new configuration mode allows installcheck-world to pass when
running the tests on an instance with pg_stat_statements enabled,
stabilizing the test output while checking the paths doing query ID
computations.
Reported-by: Anton Melnikov
Reviewed-by: Julien Rouhaud
Discussion: https://postgr.es/m/1634283396.372373993@f75.i.mail.ru
Discussion: https://postgr.es/m/YgHlxgc/OimuPYhH@paquier.xyz
Backpatch-through: 14
Commit 75d22069e tried to throw a warning for setting a custom GUC whose
prefix belongs to a previously-loaded extension, if there is no such GUC
defined by the extension. But that caused unstable behavior with
parallel workers, because workers don't necessarily load extensions and
GUCs in the same order their leader did. To make that work safely, we
have to completely disallow the case. We now actually remove any such
GUCs at the time of initial extension load, and then throw an error not
just a warning if you try to add one later. While this might create a
compatibility issue for a few people, the improvement in error-detection
capability seems worth it; it's hard to believe that there's any good
use-case for choosing such GUC names.
This also un-reverts 5609cc01c (Rename EmitWarningsOnPlaceholders() to
MarkGUCPrefixReserved()), since that function's old name is now even
more of a misnomer.
Florin Irion and Tom Lane
Discussion: https://postgr.es/m/1902182.1640711215@sss.pgh.pa.us
Commit <FIXME> fixed the bug that RemoveTempRelationsCallback() did not
push/register a snapshot. That only went unnoticed because often a valid
catalog snapshot exists and is returned by GetOldestSnapshot(). But due to
invalidation processing that is not reliable.
Thus assert in init_toast_snapshot() that there is a registered or active
snapshot, using the new HaveRegisteredOrActiveSnapshot().
Author: Andres Freund
Discussion: https://postgr.es/m/20220219180002.6tubjq7iw7m52bgd@alap3.anarazel.de
There were a number of places in the code that used bespoke bit-twiddling
expressions to do bitwise rotation. While we've had pg_rotate_right32()
for a while now, we hadn't gotten around to standardizing on that. Do so
now. Since many potential call sites look more natural with the "left"
equivalent, add that function too.
Reviewed by Tom Lane and Yugo Nagata
Discussion:
https://www.postgresql.org/message-id/CAFBsxsH7c1LC0CGZ0ADCBXLHU5-%3DKNXx-r7tHYPAW51b2HK4Qw%40mail.gmail.com
GCC 12 complains that set_stack_base is storing the address of
a local variable in a long-lived pointer. This is an entirely
reasonable warning (indeed, it just helped us find a bug);
but that behavior is intentional here. We can work around it
by using __builtin_frame_address(0) instead of a specific local
variable; that produces an address a dozen or so bytes different,
in my testing, but we don't care about such a small difference.
Maybe someday a compiler lacking that function will start to issue
a similar warning, but we'll worry about that when it happens.
Patch by me, per a suggestion from Andres Freund. Back-patch to
v12, which is as far back as the patch will go without some pain.
(Recently-established project policy would permit a back-patch as
far as 9.2, but I'm disinclined to expend the work until GCC 12
is much more widespread.)
Discussion: https://postgr.es/m/3773792.1645141467@sss.pgh.pa.us
Commit 6e0cb3dec1 allowed postgres_fdw.application_name to include
escape sequences %a (application name), %d (database name), %u (user name)
and %p (pid). In addition to them, this commit makes it support
the escape sequences for session ID (%c) and cluster name (%C).
These are helpful to investigate where each remote transactions came from.
Author: Fujii Masao
Reviewed-by: Ryohei Takahashi, Kyotaro Horiguchi
Discussion: https://postgr.es/m/1041dc9a-c976-049f-9f14-e7d94c29c4b2@oss.nttdata.com
This routine is a no-op since dd04e95 from 2003, with a macro kept
around for compatibility purposes. This has led to the same code
patterns being copy-pasted around for no effect, sometimes in confusing
ways like in pg_logical_slot_get_changes_guts() from logical.c where the
code was actually incorrect.
This issue has been discussed on two different threads recently, so
rather than living with this legacy, remove any uses of this routine in
the C code to simplify things. The compatibility macro is kept to avoid
breaking any out-of-core modules that depend on it.
Reported-by: Tatsuhito Kasahara, Justin Pryzby
Author: Tatsuhito Kasahara
Discussion: https://postgr.es/m/20211217200419.GQ17618@telsasoft.com
Discussion: https://postgr.es/m/CAP0=ZVJeeYfAeRfmzqAF2Lumdiv4S4FewyBnZd4DPTrsSQKJKw@mail.gmail.com
This moves the functions related to performing WAL recovery into the new
xlogrecovery.c source file, leaving xlog.c responsible for maintaining
the WAL buffers, coordinating the startup and switch from recovery to
normal operations, and other miscellaneous stuff that have always been in
xlog.c.
Reviewed-by: Andres Freund, Kyotaro Horiguchi, Robert Haas
Discussion: https://www.postgresql.org/message-id/a31f27b4-a31d-f976-6217-2b03be646ffa%40iki.fi
The AF_UNIX macro was being used unprotected by HAVE_UNIX_SOCKETS,
apparently since 2008. So the redirection through IS_AF_UNIX() is
apparently no longer necessary. (More generally, all supported
platforms are now HAVE_UNIX_SOCKETS, but even if there were a new
platform in the future, it seems plausible that it would define the
AF_UNIX symbol even without kernel support.) So remove the
IS_AF_UNIX() macro and make the code a bit more consistent.
Discussion: https://www.postgresql.org/message-id/flat/f2d26815-9832-e333-d52d-72fbc0ade896%40enterprisedb.com
Previously, replication slots were released in ProcKill() on error, resulting
in reporting replication slot drop of ephemeral slots after the stats
subsystem was already shut down.
To fix this problem, move replication slot release to a before_shmem_exit()
hook that is called before the stats collector shuts down. There wasn't really
a good reason for the slot handling to be in ProcKill() anyway.
Patch by Masahiko Sawada, with very minor polishing by me.
I, Andres, wrote a test for dropping slots during process exit, but there may
be some OS dependent issues around the number of times FATAL error messages
are displayed due to a still debated libpq issue. So that test will be
committed separately / later.
Reviewed-By: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Reviewed-By: Andres Freund <andres@anarazel.de>
Author: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/CAD21AoDAeEpAbZEyYJsPZJUmSPaRicVSBObaL7sPaofnKz+9zg@mail.gmail.com
This adds to database objects the same version tracking that collation
objects have. There is a new pg_database column datcollversion that
stores the version, a new function
pg_database_collation_actual_version() to get the version from the
operating system, and a new subcommand ALTER DATABASE ... REFRESH
COLLATION VERSION.
This was not originally added together with pg_collation.collversion,
since originally version tracking was only supported for ICU, and ICU
on a database-level is not currently supported. But we now have
version tracking for glibc (since PG13), FreeBSD (since PG14), and
Windows (since PG13), so this is useful to have now.
Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/f0ff3190-29a3-5b39-a179-fa32eee57db6%40enterprisedb.com
Provide a way for WaitEventSet to report that the remote peer has shut
down its socket, independently of whether there is any buffered data
remaining to be read. This works only on systems where the kernel
exposes that information, namely:
* WAIT_USE_POLL builds using POLLRDHUP, if available
* WAIT_USE_EPOLL builds using EPOLLRDHUP
* WAIT_USE_KQUEUE builds using EV_EOF
Reviewed-by: Zhihong Yu <zyu@yugabyte.com>
Reviewed-by: Maksim Milyutin <milyutinma@gmail.com>
Discussion: https://postgr.es/m/77def86b27e41f0efcba411460e929ae%40postgrespro.ru
Report on scanned pages within VACUUM VERBOSE and autovacuum logging.
These are pages that were physically examined during the VACUUM
operation. Note that this can include a small number of pages that were
marked all-visible in the visibility map by some earlier VACUUM
operation. VACUUM won't skip all-visible pages that aren't part of a
range of all-visible pages that's at least 32 blocks in length (partly
to avoid missing out on opportunities to advance relfrozenxid during
non-aggressive VACUUMs).
Commit 44fa8488 simplified the definition of scanned pages. It became
the complement of the pages (of those pages from rel_pages) that were
skipped using the visibility map. And so scanned pages precisely
indicates how effective the visibility map was at saving work. (Before
now we displayed the number of pages skipped via the visibility map when
happened to be frozen pages, but not when they were merely all-visible,
which was less useful to users.)
Rename the user-visible OldestXmin output field to "removal cutoff", and
show some supplementary information: how far behind the cutoff is
(number of XIDs behind) by the time the VACUUM operation finished. This
will help users to figure out what's _not_ working in extreme cases
where VACUUM is fundamentally unable to remove dead tuples or freeze
older tuples (e.g., due to a leaked replication slot). Also report when
relfrozenxid is advanced by VACUUM in output that immediately follows
"removal cutoff". This structure is intended to highlight the
relationship between the new relfrozenxid value for the table, and the
VACUUM operation's removal cutoff.
Finally, add instrumentation of "missed dead tuples", and the number of
pages that had at least one such tuple. These are fully DEAD (not just
RECENTLY_DEAD) tuples with storage that could not be pruned due to
failure to acquire a cleanup lock on a heap page. This is a replacement
for the "skipped due to pin" instrumentation removed by commit 44fa8488.
It shows more details than before for pages where failing to get a
cleanup lock actually resulted in VACUUM missing out on useful work, but
usually shows nothing at all instead (the mere fact that we couldn't get
a cleanup lock is usually of no consequence whatsoever now).
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CAH2-Wznp=c=Opj8Z7RMR3G=ec3_JfGYMN_YvmCEjoPCHzWbx0g@mail.gmail.com
Previously, it was possible for DROP DATABASE, DROP TABLESPACE and ALTER
DATABASE SET TABLESPACE to fail because other backends still had file
handles open for dropped tables. Windows won't allow a directory
containing unlinked-but-still-open files to be unlinked. Tackle this
problem by forcing all backends to close all smgr fds. No change for
Unix systems, which don't suffer from the problem, but the new code path
can be tested by Unix-based developers by defining
USE_BARRIER_SMGRRELEASE explicitly.
It's possible that PROCSIGNAL_BARRIER_SMGRRELEASE will have more
bug-fixing applications soon (under discussion). Note that this is the
first user of the ProcSignalBarrier mechanism from commit 16a4e4aec. It
could in principle be back-patched as far as 14, but since field
complaints are rare and ProcSignalBarrier hasn't been battle-tested,
that seems like a bad idea. Fix in master only, where these failures
have started to show up in automated testing due to new tests.
Suggested-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/CA+hUKGLdemy2gBm80kz20GTe6hNVwoErE8KwcJk6-U56oStjtg@mail.gmail.com
LZ4 compression can be a lot faster than gzip compression, so users
may prefer it even if the compression ratio is not as good. We will
want pg_basebackup to support LZ4 compression and decompression on the
client side as well, and there is a pending patch for that, but it's
by a different author, so I am committing this part separately for
that reason.
Jeevan Ladhe, reviewed by Tushar Ahuja and by me.
Discussion: http://postgr.es/m/CANm22Cg9cArXEaYgHVZhCnzPLfqXCZLAzjwTq7Fc0quXRPfbxA@mail.gmail.com
This extends the logical decoding to also decode sequence increments.
We differentiate between sequences created in the current (in-progress)
transaction, and sequences created earlier. This mixed behavior is
necessary because while sequences are not transactional (increments are
not subject to ROLLBACK), relfilenode changes are. So we do this:
* Changes for sequences created in the same top-level transaction are
treated as transactional, i.e. just like any other change from that
transaction, and discarded in case of a rollback.
* Changes for sequences created earlier are applied immediately, as if
performed outside any transaction. This applies also after ALTER
SEQUENCE, which may create a new relfilenode.
Moreover, if we ever get support for DDL replication, the sequence
won't exist until the transaction gets applied.
Sequences created in the current transaction are tracked in a simple
hash table, identified by a relfilenode. That means a sequence may
already exist, but if a transaction does ALTER SEQUENCE then the
increments for the new relfilenode will be treated as transactional.
For each relfilenode we track the XID of (sub)transaction that created
it, which is needed for cleanup at transaction end. We don't need to
check the XID to decide if an increment is transactional - if we find a
match in the hash table, it has to be the same transaction.
This requires two minor changes to WAL-logging. Firstly, we need to
ensure the sequence record has a valid XID - until now the the increment
might have XID 0 if it was the first change in a subxact. But the
sequence might have been created in the same top-level transaction. So
we ensure the XID is assigned when WAL-logging increments.
The other change is addition of "created" flag, marking increments for
newly created relfilenodes. This makes it easier to maintain the hash
table of sequences that need transactional handling.
Note: This is needed because of subxacts. A XID 0 might still have the
sequence created in a different subxact of the same top-level xact.
This does not include any changes to test_decoding and/or the built-in
replication - those will be committed in separate patches.
A patch adding decoding of sequences was originally submitted by Cary
Huang. This commit reworks various important aspects (e.g. the WAL
logging and transactional/non-transactional handling). However, the
original patch and reviews were very useful.
Author: Tomas Vondra, Cary Huang
Reviewed-by: Peter Eisentraut, Hannu Krosing, Andres Freund
Discussion: https://postgr.es/m/d045f3c2-6cfb-06d3-5540-e63c320df8bc@enterprisedb.com
Discussion: https://postgr.es/m/1710ed7e13b.cd7177461430746.3372264562543607781@highgo.ca
Commit cc333f32336f5146b75190f57ef587dff225f565 added a new COPY
sub-protocol for taking base backups, but retained support for the
previous protocol. For the same reasons articulated in the message
for commit 9cd28c2e5f11dfeef64a14035b82e70acead65fd, remove support
for the previous protocol from the server.
Discussion: http://postgr.es/m/CA+TgmoazKcKUWtqVa0xZqSzbKgTH+X-aw4V7GyLD68EpDLMh8A@mail.gmail.com
Commit 6a2a70a02 supposed that any platform having <sys/epoll.h>
would also have <sys/signalfd.h>. It turns out there are still a
few people using platforms where that's not so, so we'd better make
a separate configure probe for it. But since it took this long to
notice, I'm content with the decision to not have a separate code
path for epoll-only machines; we'll just fall back to using poll()
for these stragglers.
Per gripe from Gabriela Serventi. Back-patch to v14 where this
code came in.
Discussion: https://postgr.es/m/CAHOHWE-JjJDfcYuLAAEO7Jk07atFAU47z8TzHzg71gbC0aMy=g@mail.gmail.com
Previously, it was really easy to write code that accessed MaxBackends
before we'd actually initialized it, especially when coding up an
extension. To make this less error-prune, introduce a new function
GetMaxBackends() which should be used to obtain the correct value.
This will ERROR if called too early. Demote the global variable to
a file-level static, so that nobody can peak at it directly.
Nathan Bossart. Idea by Andres Freund. Review by Greg Sabino Mullane,
by Michael Paquier (who had doubts about the approach), and by me.
Discussion: http://postgr.es/m/20210802224204.bckcikl45uezv5e4@alap3.anarazel.de
Running a shell command for each file to be archived has a lot of
overhead and may not offer as much error checking as you want, or the
exact semantics that you want. So, offer the option to call a loadable
module for each file to be archived, rather than running a shell command.
Also, add a 'basic_archive' contrib module as an example implementation
that archives to a local directory.
Nathan Bossart, with a little bit of kibitzing by me.
Discussion: http://postgr.es/m/20220202224433.GA1036711@nathanxps13
The SQL standard has been ambiguous about whether null values in
unique constraints should be considered equal or not. Different
implementations have different behaviors. In the SQL:202x draft, this
has been formalized by making this implementation-defined and adding
an option on unique constraint definitions UNIQUE [ NULLS [NOT]
DISTINCT ] to choose a behavior explicitly.
This patch adds this option to PostgreSQL. The default behavior
remains UNIQUE NULLS DISTINCT. Making this happen in the btree code
is pretty easy; most of the patch is just to carry the flag around to
all the places that need it.
The CREATE UNIQUE INDEX syntax extension is not from the standard,
it's my own invention.
I named all the internal flags, catalog columns, etc. in the negative
("nulls not distinct") so that the default PostgreSQL behavior is the
default if the flag is false.
Reviewed-by: Maxim Orlov <orlovmg@gmail.com>
Reviewed-by: Pavel Borisov <pashkin.elfe@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/84e5ee1b-387e-9a54-c326-9082674bde78@enterprisedb.com
The comment for PGAC_READLINE_VARIABLES says "Readline versions < 2.1
don't have rl_completion_append_character". It seems certain that such
versions are extinct in the wild, though; for sure there are none in the
buildfarm. Libedit has had this variable for at least twenty years too.
Also, tab-complete.c's behavior without it is quite unfriendly, since
we'll emit a space even when completion fails; but we've had no
complaints about that.
Therefore, let's assume this variable is always there, and drop the
configure check to save a few build cycles.
Discussion: https://postgr.es/m/147685.1643858911@sss.pgh.pa.us
Some cleanup for commit 54637508f87bd5f07fb9406bac6b08240283be3b:
Reformat pg_database.dat to reflect the new field order. Also update
the corresponding example in bki.sgml. Reorder the way the fields are
filled in dbcommands.c to correspond to the new order.
The most meaningful flags are shown, which are the ones useful for the
user and for automating and extending the set of tests supported
currently by check_guc.
This script may actually be removed in the future, but we are not
completely sure yet if and how we want to support the remaining sanity
checks performed there, that are now integrated in the main regression
test suite as of this commit.
Thanks also to Peter Eisentraut and Kyotaro Horiguchi for the
discussion.
Bump catalog version.
Author: Justin Pryzby
Discussion: https://postgr.es/m/20211129030833.GJ17618@telsasoft.com
