nbtree preprocessing's handling of redundant (and contradictory) keys
created problems for scans with = arrays. It was just about possible
for a scan with an = array key and one or more redundant keys (keys that
preprocessing could not eliminate due an incomplete opfamily and a
cross-type key) to get stuck. Testing has shown that infinite cycling
where the scan never manages to make forward progress was possible.
This could happen when the scan's arrays were reset in _bt_readpage's
forcenonrequired=true path (added by bugfix commit 5f4d98d4) when the
arrays weren't at least advanced up to the same point that they were in
at the start of the _bt_readpage call. Earlier redundant keys prevented
the finaltup call to _bt_advance_array_keys from reaching lower-order
keys that needed to be used to sufficiently advance the scan's arrays.
To fix, make preprocessing leave the scan's keys in a state that is as
close as possible to how it'll usually leave them (in the common case
where there's no redundant keys that preprocessing failed to eliminate).
Now nbtree preprocessing _reliably_ leaves behind at most one required
>/>= key per index column, and at most one required </<= key per index
column. Columns that have one or more = keys that are eligible to be
marked required (based on the traditional rules) prioritize the = keys
over redundant inequality keys; they'll _reliably_ be left with only one
of the = keys as the index column's only required key.
Keys that are not marked required (whether due to the new preprocessing
step running or for some other reason) are relocated to the end of the
so->keyData[] array as needed. That way they'll always be evaluated
after the scan's required keys, and so cannot prevent code in places
like _bt_advance_array_keys and _bt_first from reaching a required key.
Also teach _bt_first to decide which initial positioning keys to use
based on the same requiredness markings that have long been used by
_bt_checkkeys/_bt_advance_array_keys. This is a necessary condition for
reliably avoiding infinite cycling. _bt_advance_array_keys expects to
be able to reason about what'll happen in the next _bt_first call should
it start another primitive index scan, by evaluating inequality keys
that were marked required in the opposite-to-scan scan direction only.
Now everybody (_bt_first, _bt_checkkeys, and _bt_advance_array_keys)
will always agree on which exact key will be used on each index column
to start and/or end the scan (except when row compare keys are involved,
which have similar problems not addressed by this commit).
An upcoming commit will finish off the work started by this commit by
harmonizing how _bt_first, _bt_checkkeys, and _bt_advance_array_keys
apply row compare keys to start and end scans.
This fixes what was arguably an oversight in either commit 5f4d98d4 or
commit 8a510275.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Discussion: https://postgr.es/m/CAH2-Wz=ds4M+3NXMgwxYxqU8MULaLf696_v5g=9WNmWL2=Uo2A@mail.gmail.com
Backpatch-through: 18
Commit c120550edb optimized the vacuuming of relations without
indexes (a.k.a. one-pass strategy) by directly marking dead item IDs
as LP_UNUSED. However, the periodic FSM vacuum was still checking if
dead item IDs had been marked as LP_DEAD when attempting to vacuum the
FSM every VACUUM_FSM_EVERY_PAGES blocks. This condition was never met
due to the optimization, resulting in missed FSM vacuum
opportunities.
This commit modifies the periodic FSM vacuum condition to use the
number of tuples deleted during HOT pruning. This count includes items
marked as either LP_UNUSED or LP_REDIRECT, both of which are expected
to result in new free space to report.
Back-patch to v17 where the vacuum optimization for tables with no
indexes was introduced.
Reviewed-by: Melanie Plageman <melanieplageman@gmail.com>
Discussion: https://postgr.es/m/CAD21AoBL8m6B9GSzQfYxVaEgvD7-Kr3AJaS-hJPHC+avm-29zw@mail.gmail.com
Backpatch-through: 17
When decompressing some input data, the calculation for the initial
starting point and the initial size were incorrect, potentially leading
to failures when decompressing contents with LZ4. These initialization
points are fixed in this commit, bringing the logic closer to what
exists for gzip and zstd.
The contents of the compressed data is clear (for example backups taken
with LZ4 can still be decompressed with a "lz4" command), only the
decompression part reading the input data was impacted by this issue.
This code path impacts pg_basebackup and pg_verifybackup, which can use
the LZ4 decompression routines with an archive streamer, or any tools
that try to use the archive streamers in src/fe_utils/.
The issue is easier to reproduce with files that have a low-compression
rate, like ones filled with random data, for a size of at least 512kB,
but this could happen with anything as long as it is stored in a data
folder. Some tests are added based on this idea, with a file filled
with random bytes grabbed from the backend, written at the root of the
data folder. This is proving good enough to reproduce the original
problem.
Author: Mikhail Gribkov <youzhick@gmail.com>
Discussion: https://postgr.es/m/CAMEv5_uQS1Hg6KCaEP2JkrTBbZ-nXQhxomWrhYQvbdzR-zy-wA@mail.gmail.com
Backpatch-through: 15
We stopped defining IOV_MAX on non-Windows systems in 75357ab94, on
the assumption that every non-Windows system defines it in <limits.h>
as required by X/Open. GNU Hurd, however, doesn't follow that
standard either. Put back the old logic to assume 16 if it's
not defined.
Author: Michael Banck <mbanck@gmx.net>
Co-authored-by: Christoph Berg <myon@debian.org>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/6862e8d1.050a0220.194b8d.76fa@mx.google.com
Discussion: https://postgr.es/m/6846e0c3.df0a0220.39ef9b.c60e@mx.google.com
Backpatch-through: 16
The existing code assumed that O_RDONLY is defined as 0, but this is
not required by POSIX and is not true on GNU Hurd. We can avoid
the assumption by relying on O_ACCMODE to mask the fcntl() result.
(Hopefully, all supported platforms define that.)
Author: Michael Banck <mbanck@gmx.net>
Co-authored-by: Samuel Thibault
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/6862e8d1.050a0220.194b8d.76fa@mx.google.com
Discussion: https://postgr.es/m/68480868.5d0a0220.1e214d.68a6@mx.google.com
Backpatch-through: 13
Querying the NUMA status can be quite time consuming, especially with
large shared buffers. 8cc139bec3 called numa_move_pages() once, for
all buffers, and we had to wait for the syscall to complete.
But with the chunking, introduced by 7fe2f67c7c to work around a kernel
bug, we can do CHECK_FOR_INTERRUPTS() after each chunk, allowing users
to abort the execution.
Reviewed-by: Christoph Berg <myon@debian.org>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/aEtDozLmtZddARdB@msg.df7cb.de
Backpatch-through: 18
When querying NUMA status of pages in shared memory, we need to touch
the memory first to get valid results. This may trigger valgrind
reports, because some of the memory (e.g. unpinned buffers) may be
marked as noaccess.
Solved by adding a valgrind suppresion. An alternative would be to
adjust the access/noaccess status before touching the memory, but that
seems far too invasive. It would require all those places to have
detailed knowledge of what the shared memory stores.
The pg_numa_touch_mem_if_required() macro is replaced with a function.
Macros are invisible to suppressions, so it'd have to suppress reports
for the caller - e.g. pg_get_shmem_allocations_numa(). So we'd suppress
reports for the whole function, and that seems to heavy-handed. It might
easily hide other valid issues.
Reviewed-by: Christoph Berg <myon@debian.org>
Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/aEtDozLmtZddARdB@msg.df7cb.de
Backpatch-through: 18
There's a kernel bug in do_pages_stat(), affecting systems combining
64-bit kernel and 32-bit user space. The function splits the request
into chunks of 16 pointers, but forgets the pointers are 32-bit when
advancing to the next chunk. Some of the pointers get skipped, and
memory after the array is interpreted as pointers. The result is that
the produced status of memory pages is mostly bogus.
Systems combining 64-bit and 32-bit environments like this might seem
rare, but that's not the case - all 32-bit Debian packages are built in
a 32-bit chroot on a system with a 64-bit kernel.
This is a long-standing kernel bug (since 2010), affecting pretty much
all kernels, so it'll take time until all systems get a fixed kernel.
Luckily, we can work around the issue by chunking the requests the same
way do_pages_stat() does, at least on affected systems. We don't know
what kernel a 32-bit build will run on, so all 32-bit builds use chunks
of 16 elements (the largest chunk before hitting the issue).
64-bit builds are not affected by this issue, and so could work without
the chunking. But chunking has other advantages, so we apply chunking
even for 64-bit builds, with chunks of 1024 elements.
Reported-by: Christoph Berg <myon@debian.org>
Author: Christoph Berg <myon@debian.org>
Author: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Discussion: https://postgr.es/m/aEtDozLmtZddARdB@msg.df7cb.de
Context: https://marc.info/?l=linux-mm&m=175077821909222&w=2
Backpatch-through: 18
Commit 1546e17f9d accidentally misspelled additionally as
additionaly. Backpatch to v17 to match where the original
commit was backpatched.
Author: Daniel Gustafsson <daniel@yesql.se>
Backpatch-through: 17
Per the checklist in RELEASE_CHANGES for the creation of a new stable
branch, this commit does the following things:
- Arm gen_node_support.pl's nodetag ABI stability, based on the contents
of nodetags.h.
- Update URLs of top-level README and Makefile to point to the new
stable version.
Run renumber_oids.pl to move high-numbered OIDs down, as per pre-beta
tasks specified by RELEASE_CHANGES. For reference, the command was
./renumber_oids.pl --first-mapped-oid 8000 --target-oid 6300
This should have been done prior to beta1, but it was forgotten. This
will ensure we get the correct numbering for beta2 onward.
This is required before the creation of a new branch. pgindent is
clean, as well as is reformat-dat-files.
perltidy version is v20230309, as documented in pgindent's README.
In the wake of commit a16ef313f, we need to deal with more cases
involving PlaceHolderVars in NestLoopParams than we did before.
For one thing, a16ef313f was incorrect to suppose that we could
rely on the required-outer relids of the lefthand path to decide
placement of nestloop-parameter PHVs. As Richard Guo argued at
the time, we must look at the required-outer relids of the join
path itself.
For another, we have to apply replace_nestloop_params() to such
a PHV's expression, in case it contains references to values that
will be supplied from NestLoopParams of higher-level nestloops.
For another, we need to be more careful about the phnullingrels
of the PHV than we were being. identify_current_nestloop_params
only bothered to ensure that the phnullingrels didn't contain
"too many" relids, but now it has to be exact, because setrefs.c
will apply both NRM_SUBSET and NRM_SUPERSET checks in different
places. We can compute the correct relids by determining the
set of outer joins that should be able to null the PHV and then
subtracting whatever's been applied at or below this join.
Do the same for plain Vars, too. (This should make it possible
to use NRM_EQUAL to process nestloop params in setrefs.c, but
I won't risk making such a change in v18 now.)
Lastly, if a nestloop parameter PHV was pulled up out of a subquery
and it contains a subquery that was originally pushed down from this
query level, then that will still be represented as a SubLink, because
SS_process_sublinks won't recurse into outer PHVs, so it didn't get
transformed during expression preprocessing in the subquery. We can
substitute the version of the PHV's expression appearing in its
PlaceHolderInfo to ensure that that preprocessing has happened.
(Seems like this processing sequence could stand to be redesigned,
but again, late in v18 development is not the time for that.)
It's not very clear to me why the old have_dangerous_phv join-order
restriction prevented us from seeing the last three of these problems.
But given the lack of field complaints, it must have done so.
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18953-1c9883a9d4afeb30@postgresql.org
Sometimes a table's constraint may depend on a column of another
table, so that we have to update the constraint when changing the
referenced column's type. We need to have lock on the constraint's
table to do that. ATPostAlterTypeCleanup believed that this case
was only possible for FOREIGN KEY constraints, but it's wrong at
least for CHECK and EXCLUDE constraints; and in general, we'd
probably need exclusive lock to alter any sort of constraint.
So just remove the contype check and acquire lock for any other
table. This prevents a "you don't have lock" assertion failure,
though no ill effect is observed in production builds.
We'll error out later anyway because we don't presently support
physically altering column types within stored composite columns.
But the catalog-munging is basically all there, so we may as well
make that part work.
Bug: #18970
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Diagnosed-by: jian he <jian.universality@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/18970-a7d1cfe1f8d5d8d9@postgresql.org
Backpatch-through: 13
This commit renames the pg_recvlogical options --two-phase and
--failover to --enable-two-phase and --enable-failover, respectively.
The new names distinguish these enabling options from action options
like --start and --create-slot, while clearly indicating their purpose
to enable specific logical slot features.
The option --failover is new in PostgreSQL 18 (commit cf2655a902), so
no compatibility break there. The option --two-phase has existed
since PostgreSQL 15 (commit cda03cfed6), so for compatibility we keep
the old option name --two-phase around as deprecated.
Also note that pg_createsubscriber has acquired an --enable-two-phase
option, so this increases consistency across tools.
Co-authored-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/a28f66df-1354-4709-8d63-932ded4cac35@eisentraut.org
ca307d5cec made CheckPointReplicationSlots() unconditionally call
ReplicationSlotsComputeRequiredLSN(). It causes an assertion trap when
max_replication_slots equals 0. This commit makes
CheckPointReplicationSlots() call ReplicationSlotsComputeRequiredLSN() only
when at least one slot gets its last_saved_restart_lsn updated. That avoids
an assert trap and also saves some cycles when no one slot has
last_saved_restart_lsn updated.
Based on ideas from Dilip Kumar <dilipbalaut@gmail.com> and
Hayato Kuroda <kuroda.hayato@fujitsu.com>.
Reported-by: Zhijie Hou <houzj.fnst@fujitsu.com>
Discussion: https://postgr.es/m/OS0PR01MB5716BB506AF934376FF3A8BB947BA%40OS0PR01MB5716.jpnprd01.prod.outlook.com
Commit 7d6d2c4bbd dropped opcintype from the index AM strategy
translation API. But some error messages about failed lookups still
mentioned it, even though it was not used for the lookup. Fix by
removing ipcintype from the error messages as well.
8e03eb92e9 reverted the commit 39b66a91bd which allowed freezing
in the heap_insert() code path but forgot to remove the corresponding
check in heap_xlog_insert(). This code is extraneous but not harmful.
However, cleaning it up makes it very clear that, as of now, we do not
support any freezing of pages in the heap_insert() path.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Tomas Vondra <tomas@vondra.me>
Discussion: https://postgr.es/m/flat/CAAKRu_Zp4Pi-t51OFWm1YZ-cctDfBhHCMZ%3DEx6PKxv0o8y2GvA%40mail.gmail.com
Backpatch-through: 14
We can simplify the VM counters added in dc6acfd910 to
lazy_vacuum_heap_page() and lazy_scan_new_or_empty().
We won't invoke lazy_vacuum_heap_page() unless there are dead line
pointers, so we know the page can't be all-visible.
In lazy_scan_new_or_empty(), we only update the VM if the page-level
hint PD_ALL_VISIBLE is clear, and the VM bit cannot be set if the page
level bit is clear because a subsequent page update would fail to clear
the visibility map bit.
Simplify the logic for determining which log counters to increment based
on this knowledge. Doing so is worthwhile because the old logic was
confusing and misguided.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Nazir Bilal Yavuz <byavuz81@gmail.com>
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
Discussion: https://postgr.es/m/flat/CAAKRu_a9w_n2mwY%3DG4LjfWTvRTJtjbfvnYAKi4WjO8QXHHrA0g%40mail.gmail.com
We were missing collecting comments for not-null constraints that are
dumped inline with the table definition (i.e., valid ones), because they
aren't represented by a separately dumpable object. Fix by creating
separate TocEntries for the comments.
Co-Authored-By: Jian He <jian.universality@gmail.com>
Co-Authored-By: Álvaro Herrera <alvherre@kurilemu.de>
Reported-By: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-By: Fujii Masao <masao.fujii@oss.nttdata.com>
Discussion: https://postgr.es/m/d50ff977-c728-4e9e-8488-fc2688e08754@oss.nttdata.com
Commit 14e87ffa5c introduced support for adding comments to NOT NULL
constraints. However, CREATE TABLE LIKE INCLUDING COMMENTS did not copy
these comments to the new table. This was an oversight in that commit.
This commit corrects the behavior by ensuring CREATE TABLE LIKE to also copy
the comments on NOT NULL constraints when INCLUDING COMMENTS is specified.
Author: Jian He <jian.universality@gmail.com>
Co-authored-by: Álvaro Herrera <alvherre@kurilemu.de>
Reviewed-by: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/127debef-e558-4784-9e24-0d5eaf91e2d1@oss.nttdata.com
The convention in the documentation for other SQL commands is to
indent continuation lines and sub-clauses in the "Synopsis" section by
4 spaces, so do the same for MERGE.
Author: Dean Rasheed <dean.a.rasheed@gmail.com>
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/CAEZATCV+9tR9+WM-SCcdBEZ3x7WVxUpADD5jX9WeGX97z4LCGA@mail.gmail.com
Backpatch-through: 15
For the subcommand ALTER COLUMN TYPE of the ALTER TABLE command, the
USING expression may reference virtual generated columns. These
columns must be expanded before the expression is fed through
expression_planner and the expression-execution machinery. Failing to
do so can result in incorrect rewrite decisions, and can also lead to
"ERROR: unexpected virtual generated column reference".
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://postgr.es/m/b5f96b24-ccac-47fd-9e20-14681b894f36@gmail.com
Just like selecting from a view is exploitable (CVE-2024-7348),
selecting from a table with virtual generated columns is exploitable.
Users who are concerned about this can avoid selecting from views, but
telling them to avoid selecting from tables is less practical.
To address this, this changes it so that generation expressions for
virtual generated columns are restricted to using built-in functions
and types, and the columns are restricted to having a built-in type.
We assume that built-in functions and types cannot be exploited for
this purpose.
In the future, this could be expanded by some new mechanism to declare
other functions and types as safe or trusted for this purpose, but
that is to be designed.
(An alternative approach might have been to expand the
restrict_nonsystem_relation_kind GUC to handle this, like the fix for
CVE-2024-7348. But that is kind of an ugly approach. That fix had to
fit in the constraints of fixing an ancient vulnerability in all
branches. Since virtual generated columns are new, we're free from
the constraints of the past, and we can and should use cleaner
options.)
Reported-by: Feike Steenbergen <feikesteenbergen@gmail.com>
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CAK_s-G2Q7de8Q0qOYUR%3D_CTB5FzzVBm5iZjOp%2BmeVWpMpmfO0w%40mail.gmail.com
Protocol v4 introduces parallel streaming, which allows Stream Abort
messages to include additional abort information such as LSN and
timestamp. However, the current documentation only states, "This field is
available since protocol version 4," which may misleadingly suggest that
the fields are always present when using protocol v4.
This patch clarifies that the abort LSN and timestamp are included only
when parallel streaming is enabled, even under protocol v4.
Author: Anthonin Bonnefoy <anthonin.bonnefoy@datadoghq.com>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Backpatch-through: 16, where it was introduced
Discussion: https://postgr.es/m/CAO6_XqoKteQR1AnaR8iPcegbBE+HkAc2-g12rxN04yOt4-2ORg@mail.gmail.com
This fixes two issues with the handling of VacuumParams in vacuum_rel().
This code path has the idea to change the passed-in pointer of
VacuumParams for the "truncate" and "index_cleanup" options for the
relation worked on, impacting the two following scenarios where
incorrect options may be used because a VacuumParams pointer is shared
across multiple relations:
- Multiple relations in a single VACUUM command.
- TOAST relations vacuumed with their main relation.
The problem is avoided by providing to the two callers of vacuum_rel()
copies of VacuumParams, before the pointer is updated for the "truncate"
and "index_cleanup" options.
The refactoring of the VACUUM option and parameters done in 0d83138974
did not introduce an issue, but it has encouraged the problem we are
dealing with in this commit, with b84dbc8eb8 for "truncate" and
a96c41feec for "index_cleanup" that have been added a couple of years
after the initial refactoring. HEAD will be improved with a different
patch that hardens the uses of VacuumParams across the tree. This
cannot be backpatched as it introduces an ABI breakage.
The backend portion of the patch has been authored by Nathan, while I
have implemented the tests. The tests rely on injection points to check
the option values, making them faster, more reliable than the tests
originally proposed by Shihao, and they also provide more coverage.
This part can only be backpatched down to v17.
Reported-by: Shihao Zhong <zhong950419@gmail.com>
Author: Nathan Bossart <nathandbossart@gmail.com>
Co-authored-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAGRkXqTo+aK=GTy5pSc-9cy8H2F2TJvcrZ-zXEiNJj93np1UUw@mail.gmail.com
Backpatch-through: 13
The documentation previously described the type of the io_workers GUC
parameter as "int". However, the documentation consistently uses "integer"
for parameters of this type.
This commit updates the type description of io_workers to "integer"
for consistency with other GUC parameter descriptions.
Author: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/e95c899a-2aeb-45b7-8fd3-7a27dcdb475b@oss.nttdata.com
The documentation for track_cost_delay_timing describes where cost-based
vacuum delay timing information is displayed when the setting is enabled.
While this information is also shown in the output of ANALYZE VERBOSE,
that was previously omitted from the list.
This commit updates the documentation to include ANALYZE VERBOSE in the list,
clarifying that it also reports cost-based delay timing information.
Author: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/e95c899a-2aeb-45b7-8fd3-7a27dcdb475b@oss.nttdata.com
For parameters that exist as both configuration and storage options,
the documentation typically includes secondary index entries to
help users distinguish and locate the relevant references easily.
However, such index entries were missing for vacuum_truncate and
vacuum_max_eager_freeze_failure_rate, both introduced in v18.
This commit adds appropriate secondary index terms for these parameters
to ensure consistency with other parameters and improve usability of
the documentation index.
Author: Fujii Masao <masao.fujii@gmail.com>
Discussion: https://postgr.es/m/e95c899a-2aeb-45b7-8fd3-7a27dcdb475b@oss.nttdata.com
The logical replication launcher process would sometimes sleep
for as much as 3 minutes before noticing that it is supposed
to launch a new worker. This could happen if
(1) WaitForReplicationWorkerAttach absorbed a process latch wakeup
that was meant to cause ApplyLauncherMain to do work, or
(2) logicalrep_worker_launch reported failure, either because of
resource limits or because the new worker terminated immediately.
In case (2), the expected behavior is that we retry the launch after
wal_retrieve_retry_interval, but that didn't reliably happen.
It's not clear how often such conditions would occur in the field,
but in our subscription test suite they are somewhat common,
especially in tests that exercise cases that cause quick worker
failure. That causes the tests to take substantially longer than
they ought to do on typical setups.
To fix (1), make WaitForReplicationWorkerAttach re-set the latch
before returning if it cleared it while looping. To fix (2), ensure
that we reduce wait_time to no more than wal_retrieve_retry_interval
when logicalrep_worker_launch reports failure. In passing, fix a
couple of perhaps-hypothetical race conditions, e.g. examining
worker->in_use without a lock.
Backpatch to v16. Problem (2) didn't exist before commit 5a3a95385
because the previous code always set wait_time to
wal_retrieve_retry_interval when launching a worker, regardless of
success or failure of the launch. That behavior also greatly
mitigated problem (1), so I'm not excited about adapting the remainder
of the patch to the substantially-different code in older branches.
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Discussion: https://postgr.es/m/817604.1750723007@sss.pgh.pa.us
Backpatch-through: 16
Commit 62d712ecfd made query jumbling squash lists of Consts as a
single element, but there's no reason not to treat PARAM_EXTERN
parameters the same. For these purposes, these values are indeed
constants for any particular execution of a query.
In particular, this should make list squashing more useful for
applications using extended query protocol, which would use parameters
extensively.
A complication arises: if a query has both external parameters and
squashable lists, then the parameter number used as placeholder for the
squashed list might be inconsistent with regards to the parameter
numbers used by the query literal. To reduce the surprise factor, all
parameters are renumbered starting from 1 in that case.
Author: Sami Imseih <samimseih@gmail.com>
Author: Dmitry Dolgov <9erthalion6@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAA5RZ0tRXoPG2y6bMgBCWNDt0Tn=unRerbzYM=oW0syi1=C1OA@mail.gmail.com
Peter Geoghegan