When this assertion was installed (in commit d2f60a3ab), I thought
it was only for catching server logic errors that caused accesses to
catalogs that were undergoing index rebuilds. However, it will also
fire in case of a user-defined index expression that attempts to
access its own table. We occasionally see reports of people trying
to do that, and typically getting unintelligible low-level errors
as a result. We can provide a more on-point message by making this
a regular runtime check.
While at it, adjust the similar error check in
systable_beginscan_ordered to use the same message text. That one
is (probably) not reachable without a coding bug, but we might as
well use a translatable message if we have one.
Per bug #18363 from Alexander Lakhin. Back-patch to all supported
branches.
Discussion: https://postgr.es/m/18363-e3598a5a572d0699@postgresql.org
The new facility makes it easier to optimize bulk loading, as the
logic for buffering, WAL-logging, and syncing the relation only needs
to be implemented once. It's also less error-prone: We have had a
number of bugs in how a relation is fsync'd - or not - at the end of a
bulk loading operation. By centralizing that logic to one place, we
only need to write it correctly once.
The new facility is faster for small relations: Instead of of calling
smgrimmedsync(), we register the fsync to happen at next checkpoint,
which avoids the fsync latency. That can make a big difference if you
are e.g. restoring a schema-only dump with lots of relations.
It is also slightly more efficient with large relations, as the WAL
logging is performed multiple pages at a time. That avoids some WAL
header overhead. The sorted GiST index build did that already, this
moves the buffering to the new facility.
The changes to pageinspect GiST test needs an explanation: Before this
patch, the sorted GiST index build set the LSN on every page to the
special GistBuildLSN value, not the LSN of the WAL record, even though
they were WAL-logged. There was no particular need for it, it just
happened naturally when we wrote out the pages before WAL-logging
them. Now we WAL-log the pages first, like in B-tree build, so the
pages are stamped with the record's real LSN. When the build is not
WAL-logged, we still use GistBuildLSN. To make the test output
predictable, use an unlogged index.
Reviewed-by: Andres Freund
Discussion: https://www.postgresql.org/message-id/30e8f366-58b3-b239-c521-422122dd5150%40iki.fi
By enabling slot synchronization, all the failover logical replication
slots on the primary (assuming configurations are appropriate) are
automatically created on the physical standbys and are synced
periodically. The slot sync worker on the standby server pings the primary
server at regular intervals to get the necessary failover logical slots
information and create/update the slots locally. The slots that no longer
require synchronization are automatically dropped by the worker.
The nap time of the worker is tuned according to the activity on the
primary. The slot sync worker waits for some time before the next
synchronization, with the duration varying based on whether any slots were
updated during the last cycle.
A new parameter sync_replication_slots enables or disables this new
process.
On promotion, the slot sync worker is shut down by the startup process to
drop any temporary slots acquired by the slot sync worker and to prevent
the worker from trying to fetch the failover slots.
A functionality to allow logical walsenders to wait for the physical will
be done in a subsequent commit.
Author: Shveta Malik, Hou Zhijie based on design inputs by Masahiko Sawada and Amit Kapila
Reviewed-by: Masahiko Sawada, Bertrand Drouvot, Peter Smith, Dilip Kumar, Ajin Cherian, Nisha Moond, Kuroda Hayato, Amit Kapila
Discussion: https://postgr.es/m/514f6f2f-6833-4539-39f1-96cd1e011f23@enterprisedb.com
Commit 6b80394781 introduced integer comparison functions designed
to be as efficient as possible while avoiding overflow. This
commit makes use of these functions in many of the in-tree qsort()
comparators to help ensure transitivity. Many of these comparator
functions should also see a small performance boost.
Author: Mats Kindahl
Reviewed-by: Andres Freund, Fabrízio de Royes Mello
Discussion: https://postgr.es/m/CA%2B14426g2Wa9QuUpmakwPxXFWG_1FaY0AsApkvcTBy-YfS6uaw%40mail.gmail.com
Previously, some callers requested XLOG_BLCKSZ bytes
unconditionally. While this did not cause a problem, because the extra
bytes are ignored, it's confusing and makes it harder to add safety
checks. Additionally, the comment about zero padding was incorrect.
With this commit, all callers request the number of bytes they
actually need.
Author: Bharath Rupireddy
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/CALj2ACWBRFac2TingD3PE3w2EBHXUHY3=AEEZPJmqhpEOBGExg@mail.gmail.com
Don't deal with transaction timeout in PostgresMain(). Instead, release
transaction timeout activated by StartTransaction() in
CommitTransaction()/AbortTransaction()/PrepareTransaction(). Deal with both
enabling and disabling transaction timeout in assign_transaction_timeout().
Also, remove potentially flaky timeouts-long isolation test, which has no
guarantees to pass on slow/busy machines.
Reported-by: Andres Freund
Discussion: https://postgr.es/m/20240215230856.pc6k57tqxt7fhldm%40awork3.anarazel.de
This commit adds timeout that is expected to be used as a prevention
of long-running queries. Any session within the transaction will be
terminated after spanning longer than this timeout.
However, this timeout is not applied to prepared transactions.
Only transactions with user connections are affected.
Discussion: https://postgr.es/m/CAAhFRxiQsRs2Eq5kCo9nXE3HTugsAAJdSQSmxncivebAxdmBjQ%40mail.gmail.com
Author: Andrey Borodin <amborodin@acm.org>
Author: Japin Li <japinli@hotmail.com>
Author: Junwang Zhao <zhjwpku@gmail.com>
Reviewed-by: Nikolay Samokhvalov <samokhvalov@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: bt23nguyent <bt23nguyent@oss.nttdata.com>
Reviewed-by: Yuhang Qiu <iamqyh@gmail.com>
If available, read directly from WAL buffers, avoiding the need to go
through the filesystem. Only for physical replication for now, but can
be expanded to other callers.
In preparation for replicating unflushed WAL data.
Author: Bharath Rupireddy
Discussion: https://postgr.es/m/CALj2ACXKKK%3DwbiG5_t6dGao5GoecMwRkhr7GjVBM_jg54%2BNa%3DQ%40mail.gmail.com
Reviewed-by: Andres Freund, Alvaro Herrera, Nathan Bossart, Dilip Kumar, Nitin Jadhav, Melih Mutlu, Kyotaro Horiguchi
Commit 861f86beea used REGBUF_NO_CHANGE at one of the places in the hash
index to register the clean buffers but forgot to avoid setting LSN in
that case.
Reported-by: Michael Paquier
Author: Kuroda Hayato
Reviewed-by: Amit Kapila, Michael Paquier
Discussion: https://postgr.es/m/ZbyVVG_7eW3YD5-A@paquier.xyz
The new concurrency model proposed for slru.c to improve performance
does not include any single lock that would coordinate processes
doing concurrent reads/writes on SlruShared->latest_page_number.
We can instead use atomic reads and writes for that variable.
Author: Dilip Kumar <dilipbalaut@gmail.com>
Reviewed-by: Andrey M. Borodin <x4mmm@yandex-team.ru>
Discussion: https://postgr.es/m/CAFiTN-vzDvNz=ExGXz6gdyjtzGixKSqs0mKHMmaQ8sOSEFZ33A@mail.gmail.com
After calling smgropen(), it was not clear how long you could continue
to use the result, because various code paths including cache
invalidation could call smgrclose(), which freed the memory.
Guarantee that the object won't be destroyed until the end of the
current transaction, or in recovery, the commit/abort record that
destroys the underlying storage.
smgrclose() is now just an alias for smgrrelease(). It closes files
and forgets all state except the rlocator, but keeps the SMgrRelation
object valid.
A new smgrdestroy() function is used by rare places that know there
should be no other references to the SMgrRelation.
The short version:
* smgrclose() is now just an alias for smgrrelease(). It releases
resources, but doesn't destroy until EOX
* smgrdestroy() now frees memory, and should rarely be used.
Existing code should be unaffected, but it is now possible for code that
has an SMgrRelation object to use it repeatedly during a transaction as
long as the storage hasn't been physically dropped. Such code would
normally hold a lock on the relation.
This also replaces the "ownership" mechanism of SMgrRelations with a
pin counter. An SMgrRelation can now be "pinned", which prevents it
from being destroyed at end of transaction. There can be multiple pins
on the same SMgrRelation. In practice, the pin mechanism is only used
by the relcache, so there cannot be more than one pin on the same
SMgrRelation. Except with swap_relation_files XXX
Author: Thomas Munro, Heikki Linnakangas
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://www.postgresql.org/message-id/CA%2BhUKGJ8NTvqLHz6dqbQnt2c8XCki4r2QvXjBQcXpVwxTY_pvA@mail.gmail.com
ginFinishSplit() expects the caller to hold an exclusive lock on the
buffer, but when finishing an earlier "leftover" incomplete split of
an internal page, the caller held a shared lock. That caused an
assertion failure in MarkBufferDirty(). Without assertions, it could
lead to corruption if two backends tried to complete the split at the
same time.
On master, add a test case using the new injection point facility.
Report and analysis by Fei Changhong. Backpatch the fix to all
supported versions.
Reviewed-by: Fei Changhong, Michael Paquier
Discussion: https://www.postgresql.org/message-id/tencent_A3CE810F59132D8E230475A5F0F7A08C8307@qq.com
lazy_scan_prune() and lazy_scan_noprune() update the freespace map
with identical conditions; combine them. This consolidation is easier
now that cb970240f1 moved visibility map
updates into lazy_scan_prune().
While combining the FSM updates, simplify the logic for calling
lazy_scan_new_or_empty() and lazy_scan_noprune().
Also update a few comemnts in this part of the code to make them,
hopefully, clearer.
Melanie Plageman and Robert Haas
Discussion: https://postgr.es/m/CA%2BTgmoaLTvipm%3Dxx4rJLr07m908PCu%3DQH3uCjD1UOn8YaEuO2g%40mail.gmail.com
Three LOG messages are added in the recovery code paths, providing
information that can be useful to track corruption issues depending on
the state of the cluster, telling that:
- Recovery has started from a backup_label.
- Recovery is restarting from a backup start LSN, without a
backup_label.
- Recovery has completed from a backup.
Author: Andres Freund
Reviewed-by: David Steele, Laurenz Albe, Michael Paquier
Discussion: https://postgr.es/m/20231117041811.vz4vgkthwjnwp2pp@awork3.anarazel.de
Add WITHOUT OVERLAPS clause to PRIMARY KEY and UNIQUE constraints.
These are backed by GiST indexes instead of B-tree indexes, since they
are essentially exclusion constraints with = for the scalar parts of
the key and && for the temporal part.
Author: Paul A. Jungwirth <pj@illuminatedcomputing.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
This is support function 12 for the GiST AM and translates
"well-known" RT*StrategyNumber values into whatever strategy number is
used by the opclass (since no particular numbers are actually
required). We will use this to support temporal PRIMARY
KEY/UNIQUE/FOREIGN KEY/FOR PORTION OF functionality.
This commit adds two implementations, one for internal GiST opclasses
(just an identity function) and another for btree_gist opclasses. It
updates btree_gist from 1.7 to 1.8, adding the support function for
all its opclasses.
Author: Paul A. Jungwirth <pj@illuminatedcomputing.com>
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: jian he <jian.universality@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/CA+renyUApHgSZF9-nd-a0+OPGharLQLO=mDHcY4_qQ0+noCUVg@mail.gmail.com
Commit cb970240f1 moved some code from
lazy_scan_heap() to lazy_scan_prune(), and now some things that used to
need to be passed back and forth are completely local to lazy_scan_prune().
Hence, this struct is mostly obsolete. The only thing that still
needs to be passed back to the caller is has_lpdead_items, and that's
also passed back by lazy_scan_noprune(), so do it the same way in both
cases.
Melanie Plageman, reviewed and slightly revised by me.
Discussion: http://postgr.es/m/CAAKRu_aM=OL85AOr-80wBsCr=vLVzhnaavqkVPRkFBtD0zsuLQ@mail.gmail.com
Most of the output parameters of lazy_scan_prune() were being
used to update the VM in lazy_scan_heap(). Moving that code into
lazy_scan_prune() simplifies lazy_scan_heap() and requires less
communication between the two.
This change permits some further code simplification, but that
is left for a separate commit.
Melanie Plageman, reviewed by me.
Discussion: http://postgr.es/m/CAAKRu_aM=OL85AOr-80wBsCr=vLVzhnaavqkVPRkFBtD0zsuLQ@mail.gmail.com
If there are no indexes on a relation, items can be marked LP_UNUSED
instead of LP_DEAD when pruning. This significantly reduces WAL
volume, since we no longer need to emit one WAL record for pruning
and a second to change the LP_DEAD line pointers thus created to
LP_UNUSED.
Melanie Plageman, reviewed by Andres Freund, Peter Geoghegan, and me
Discussion: https://postgr.es/m/CAAKRu_bgvb_k0gKOXWzNKWHt560R0smrGe3E8zewKPs8fiMKkw%40mail.gmail.com
try_index_open() is able to open an index if its relkind fits, except
that it would return NULL instead of generated an error if the relation
does not exist. This new routine will be used by an upcoming patch to
make REINDEX on partitioned relations more robust when an index in a
partition tree is dropped.
Extracted from a larger patch by the same author.
Author: Fei Changhong
Discussion: https://postgr.es/m/tencent_6A52106095ACDE55333E3AD33F304C0C3909@qq.com
Backpatch-through: 14
Previously, when lazy_scan_noprune() was called and returned true, we would
update the FSM immediately if the relation had no indexes or if the page
contained no dead items. On the other hand, when lazy_scan_prune() was
called, we would update the FSM if either of those things was true or
if index vacuuming was disabled. Eliminate that behavioral difference by
considering vacrel->do_index_vacuuming in both cases.
Also, make lazy_scan_heap() responsible for deciding whether to update
the FSM, instead of doing it inside lazy_scan_noprune(). This is
more consistent with the lazy_scan_prune() case. lazy_scan_noprune()
still needs an output parameter for whether there are LP_DEAD items
on the page, but the real decision-making now happens in the caller.
Patch by me, reviewed by Peter Geoghegan and Melanie Plageman.
Discussion: http://postgr.es/m/CA+TgmoaOzvN1TcHd9iej=PR3fY40En1USxzOnXSR2CxCLaRM0g@mail.gmail.com
This changes the pg_attribute field attstattarget into a nullable
field in the variable-length part of the row. If no value is set by
the user for attstattarget, it is now null instead of previously -1.
This saves space in pg_attribute and tuple descriptors for most
practical scenarios. (ATTRIBUTE_FIXED_PART_SIZE is reduced from 108
to 104.) Also, null is the semantically more correct value.
The ANALYZE code internally continues to represent the default
statistics target by -1, so that that code can avoid having to deal
with null values. But that is now contained to the ANALYZE code.
Only the DDL code deals with attstattarget possibly null.
For system columns, the field is now always null. The ANALYZE code
skips system columns anyway.
To set a column's statistics target to the default value, the new
command form ALTER TABLE ... SET STATISTICS DEFAULT can be used. (SET
STATISTICS -1 still works.)
Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://www.postgresql.org/message-id/flat/4da8d211-d54d-44b9-9847-f2a9f1184c76@eisentraut.org
Instead, just have lazy_scan_prune() and lazy_scan_noprune() update
LVRelState->nonempty_pages directly. This makes the two functions
more similar and also removes makes lazy_scan_noprune need one fewer
output parameters.
Melanie Plageman, reviewed by Andres Freund, Michael Paquier, and me
Discussion: http://postgr.es/m/CAAKRu_btji_wQdg=ok-5E4v_bGVxKYnnFFe7RA6Frc1EcOwtSg@mail.gmail.com
The brinbuildCallbackParallel callback used by parallel BRIN builds did
not consider that the parallel table scans may be synchronized, starting
from an arbitrary block and then wrap around.
If this happened and the scan actually did wrap around, tuples from the
beginning of the table were added to the last range produced by the same
worker. The index would be missing range at the beginning of the table,
while the last range would be too wide. This would not produce incorrect
query results, but it'd be less efficient.
Fixed by checking for both past and future ranges in the callback. The
worker may produce multiple summaries for the same page range, but the
leader will merge them as if the summaries came from different workers.
Discussion: https://postgr.es/m/c2ee7d69-ce17-43f2-d1a0-9811edbda6e6%40enterprisedb.com
Commit b437571714 added support for parallel builds for BRIN indexes,
using code similar to BTREE parallel builds, and also a new tuplesort
variant. This commit simplifies the new code in two ways:
* The "spool" grouping tuplesort and the heap/index is not necessary.
The heap/index are available as separate arguments, causing confusion.
So remove the spool, and use the tuplesort directly.
* The new tuplesort variant does not need the heap/index, as it sorts
simply by the range block number, without accessing the tuple data.
So simplify that too.
Initial report and patch by Ranier Vilela, further cleanup by me.
Author: Ranier Vilela
Discussion: https://postgr.es/m/CAEudQAqD7f2i4iyEaAz-5o-bf6zXVX-AkNUBm-YjUXEemaEh6A%40mail.gmail.com
Recently-introduced code in reconstruct.c was using "unsigned"
to store the result of read(), pg_pread(), or write(). This is
completely bogus: it breaks subsequent tests for the result being
negative, as we're being reminded of by a chorus of buildfarm
warnings. Switch to "int" as was doubtless intended. (There are
several other uses of "unsigned" in this file that also look poorly
chosen to me, but for now I'm just trying to clean up the buildfarm.)
A larger problem is that "int" is not necessarily wide enough to hold
the result: per POSIX, all these functions return ssize_t. In places
where the requested read or write length clearly fits in int, that's
academic. It may be academic anyway as long as we constrain
individual data files to 1GB, since even a readv or writev-like
operation would then not be responsible for transferring more than
1GB. Nonetheless it seems like trouble waiting to happen, so I made
a pass over readv and writev calls and fixed the result variables
where that seemed appropriate. We might want to think about changing
some of the fd.c functions to return ssize_t too, for future-proofing;
but I didn't tackle that here.
Discussion: https://postgr.es/m/1672202.1703441340@sss.pgh.pa.us
e0b1ee17dc introduced optimization for matching B-tree scan keys required for
the directional scan. However, it incorrectly assumed that all keys required
for opposite direction scan are satisfied by _bt_first(). It has been
illustrated that with multiple scan keys over the same column, a lesser one
(according to the scan direction) could win leaving the other one unsatisfied.
Instead of relying on _bt_first() this commit introduces code that memorizes
whether there was at least one match on the page. If that's true we know that
keys required for opposite-direction scan are satisfied as soon as
corresponding values are not NULLs.
Also, this commit simplifies the description for the optimization of keys
required for the current direction scan. Now the flag used for this is named
continuescanPrechecked and means exactly that *continuescan flag is known
to be true for the last item on the page.
Reported-by: Peter Geoghegan
Discussion: https://postgr.es/m/CAH2-Wzn0LeLcb1PdBnK0xisz8NpHkxRrMr3NWJ%2BKOK-WZ%2BQtTQ%40mail.gmail.com
Reviewed-by: Pavel Borisov
It's not necessary to keep the firstPage flag as a field of BTScanOpaqueData.
This commit makes it an argument of the _bt_readpage() function. We can easily
distinguish first-time and repeated calls (within the scan) of this function.
Reported-by: Peter Geoghegan
Discussion: https://postgr.es/m/CAH2-Wzk4SOsw%2BtHuTFiz8U9Jqj-R77rYPkhWKODCBb1mdHACXA%40mail.gmail.com
Reviewed-by: Pavel Borisov
This is necessary when spgcanreturn() is invoked on a partitioned
index, and the failure might be reachable in other scenarios as
well. The rest of what spgGetCache() does is perfectly sensible
for a partitioned index, so we should allow it to go through.
I think the main takeaway from this is that we lack sufficient test
coverage for non-btree partitioned indexes. Therefore, I added
simple test cases for brin and gin as well as spgist (hash and
gist AMs were covered already in indexing.sql).
Per bug #18256 from Alexander Lakhin. Although the known test case
only fails since v16 (3c569049b), I've got no faith at all that there
aren't other ways to reach this problem; so back-patch to all
supported branches.
Discussion: https://postgr.es/m/18256-0b0e1b6e4a620f1b@postgresql.org
Commit 6af179395 added isCatalogRel field to some WAL record types,
but this field was not shown in the rmgr descriptions. This commit
changes the several rmgr descriptions to display the isCatalogRel
field.
Author: Bertrand Drouvot
Reviewed-by: Michael Paquier, Masahiko Sawada
Discussion: https://postgr.es/m/957dc8f9-2a02-4640-9c01-9dcbf97c4187%40gmail.com
To take an incremental backup, you use the new replication command
UPLOAD_MANIFEST to upload the manifest for the prior backup. This
prior backup could either be a full backup or another incremental
backup. You then use BASE_BACKUP with the INCREMENTAL option to take
the backup. pg_basebackup now has an --incremental=PATH_TO_MANIFEST
option to trigger this behavior.
An incremental backup is like a regular full backup except that
some relation files are replaced with files with names like
INCREMENTAL.${ORIGINAL_NAME}, and the backup_label file contains
additional lines identifying it as an incremental backup. The new
pg_combinebackup tool can be used to reconstruct a data directory
from a full backup and a series of incremental backups.
Patch by me. Reviewed by Matthias van de Meent, Dilip Kumar, Jakub
Wartak, Peter Eisentraut, and Álvaro Herrera. Thanks especially to
Jakub for incredibly helpful and extensive testing.
Discussion: http://postgr.es/m/CA+TgmoYOYZfMCyOXFyC-P+-mdrZqm5pP2N7S-r0z3_402h9rsA@mail.gmail.com
When active, this process writes WAL summary files to
$PGDATA/pg_wal/summaries. Each summary file contains information for a
certain range of LSNs on a certain TLI. For each relation, it stores a
"limit block" which is 0 if a relation is created or destroyed within
a certain range of WAL records, or otherwise the shortest length to
which the relation was truncated during that range of WAL records, or
otherwise InvalidBlockNumber. In addition, it stores a list of blocks
which have been modified during that range of WAL records, but
excluding blocks which were removed by truncation after they were
modified and never subsequently modified again.
In other words, it tells us which blocks need to copied in case of an
incremental backup covering that range of WAL records. But this
doesn't yet add the capability to actually perform an incremental
backup; the next patch will do that.
A new parameter summarize_wal enables or disables this new background
process. The background process also automatically deletes summary
files that are older than wal_summarize_keep_time, if that parameter
has a non-zero value and the summarizer is configured to run.
Patch by me, with some design help from Dilip Kumar and Andres Freund.
Reviewed by Matthias van de Meent, Dilip Kumar, Jakub Wartak, Peter
Eisentraut, and Álvaro Herrera.
Discussion: http://postgr.es/m/CA+TgmoYOYZfMCyOXFyC-P+-mdrZqm5pP2N7S-r0z3_402h9rsA@mail.gmail.com
First, mark the xlblocks member with InvalidXLogRecPtr, then issue a
write barrier, then initialize it. That ensures that the xlblocks
member doesn't appear valid while the contents are being initialized.
In preparation for reading WAL buffer contents without a lock.
Author: Bharath Rupireddy
Discussion: https://postgr.es/m/CALj2ACVfFMfqD5oLzZSQQZWfXiJqd-NdX0_317veP6FuB31QWA@mail.gmail.com
Reviewed-by: Andres Freund
Dead tuples are ignored and are not marked as dead during recovery, as
it can lead to MVCC issues on a standby because its xmin may not match
with the primary. This information is tracked by a field called
"xactStartedInRecovery" in the transaction state data, switched on when
starting a transaction in recovery.
Unfortunately, this information was not correctly tracked when starting
a subtransaction, because the transaction state used for the
subtransaction did not update "xactStartedInRecovery" based on the state
of its parent. This would cause index scans done in subtransactions to
return inconsistent data, depending on how the xmin of the primary
and/or the standby evolved.
This is broken since the introduction of hot standby in efc16ea520, so
backpatch all the way down.
Author: Fei Changhong
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/tencent_C4D907A5093C071A029712E73B43C6512706@qq.com
Backpatch-through: 12
This GUC was intended as a debugging help in the 9.0 area when hot
standby and streaming replication were being developped, able to offer
more information at LOG level rather than DEBUGn. There are more tools
available these days that are able to offer rather equivalent
information, like pg_waldump introduced in 9.3. It is not obvious how
this facility is useful these days, so let's remove it.
Author: Bharath Rupireddy
Discussion: https://postgr.es/m/ZXEXEAUVFrvpquSd@paquier.xyz
Remove comments that supposed that holding a pin was a useful interlock
for _bt_walk_left(). There are times when _bt_walk_left() doesn't hold
either a lock or a pin on any page, so clearly this can't be true.
_bt_walk_left() is even prepared to deal with concurrent deletion of
both the original page and any pages to its left.
Oversight in commit 2ed5b87f96.
Teach _bt_binsrch (and related helper routines like _bt_search and
_bt_compare) about the initial positioning requirements of backward
scans. Routines like _bt_binsrch already know all about "nextkey"
searches, so it seems natural to teach them about "goback"/backward
searches, too. These concepts are closely related, and are much easier
to understand when discussed together.
Now that certain implementation details are hidden from _bt_first, it's
straightforward to add a new optimization: backward scans using the <
strategy now avoid extra leaf page accesses in certain "boundary cases".
Consider the following example, which uses the tenk1 table (and its
tenk1_hundred index) from the standard regression tests:
SELECT * FROM tenk1 WHERE hundred < 12 ORDER BY hundred DESC LIMIT 1;
Before this commit, nbtree would scan two leaf pages, even though it was
only really necessary to scan one leaf page. We'll now descend straight
to the leaf page containing a (12, -inf) high key instead. The scan
will locate matching non-pivot tuples with "hundred" values starting
from the value 11. The scan won't waste a page access on the right
sibling leaf page, which cannot possibly contain any matching tuples.
You can think of the optimization added by this commit as disabling an
optimization (the _bt_compare "!pivotsearch" behavior that was added to
Postgres 12 in commit dd299df8) for a small subset of cases where it was
always counterproductive.
Equivalently, you can think of the new optimization as extending the
"pivotsearch" behavior that page deletion by VACUUM has long required
(since the aforementioned Postgres 12 commit went in) to other, similar
cases. Obviously, this isn't strictly necessary for these new cases
(unlike VACUUM, _bt_first is prepared to move the scan to the left once
on the leaf level), but the underlying principle is the same.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Matthias van de Meent <boekewurm+postgres@gmail.com>
Discussion: https://postgr.es/m/CAH2-Wz=XPzM8HzaLPq278Vms420mVSHfgs9wi5tjFKHcapZCEw@mail.gmail.com
Allow using multiple worker processes to build BRIN index, which until
now was supported only for BTREE indexes. For large tables this often
results in significant speedup when the build is CPU-bound.
The work is split in a simple way - each worker builds BRIN summaries on
a subset of the table, determined by the regular parallel scan used to
read the data, and feeds them into a shared tuplesort which sorts them
by blkno (start of the range). The leader then reads this sorted stream
of ranges, merges duplicates (which may happen if the parallel scan does
not align with BRIN pages_per_range), and adds the resulting ranges into
the index.
The number of duplicate results produced by workers (requiring merging
in the leader process) should be fairly small, thanks to how parallel
scans assign chunks to workers. The likelihood of duplicate results may
increase for higher pages_per_range values, but then there are fewer
page ranges in total. In any case, we expect the merging to be much
cheaper than summarization, so this should be a win.
Most of the parallelism infrastructure is a simplified copy of the code
used by BTREE indexes, omitting the parts irrelevant for BRIN indexes
(e.g. uniqueness checks).
This also introduces a new index AM flag amcanbuildparallel, determining
whether to attempt to start parallel workers for the index build.
Original patch by me, with reviews and substantial reworks by Matthias
van de Meent, certainly enough to make him a co-author.
Author: Tomas Vondra, Matthias van de Meent
Reviewed-by: Matthias van de Meent
Discussion: https://postgr.es/m/c2ee7d69-ce17-43f2-d1a0-9811edbda6e6%40enterprisedb.com
When building BRIN indexes, the brinbuildCallback only advances to the
next page range when seeing a tuple that doesn't belong to the current
one. This means that the index may end up missing ranges at the end of
the table, if those pages do not contain any indexable tuples.
We tend not to have completely empty pages at the end of a relation, but
this also applies to partial indexes, where the tuples may simply not
match the index predicate. This results in inefficient scans using the
affected BRIN index - without the summaries, the page ranges have to be
read and processed, which consumes I/O and possibly also CPU time.
The existing code already added empty ranges for earlier parts of the
table, this commit makes sure we add them for the ranges at the end of
the table too.
Patch by Matthias van de Meent, with review/improvements by me.
Author: Matthias van de Meent
Reviewed-by: Tomas Vondra
Discussion: https://postgr.es/m/CAEze2WiMsPZg%3DxkvSF_jt4%3D69k6K7gz5B8V2wY3gCGZ%2B1BzCbQ%40mail.gmail.com
While checking if a record could fit in the circular WAL decoding
buffer, the coding from commit 3f1ce973 used arithmetic that could
overflow. 64 bit systems were unaffected for various technical reasons,
which probably explains the lack of problem reports. Likewise for 32
bit systems running known 32 bit kernels. The systems at risk of
problems appear to be 32 bit processes running on 64 bit kernels, with
unlucky placement in memory.
Per complaint from GCC -fsanitize=undefined -m32, while testing
variations of 039_end_of_wal.pl.
Back-patch to 15.
Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKGKH0oRPOX7DhiQ_b51sM8HqcPp2J3WA-Oen%3DdXog%2BAGGQ%40mail.gmail.com
Commit 861f86beea changed hash_xlog_squeeze_page() to start reading
the write buffer conditionally but forgot to initialize it leading to an
uninitialized access.
Reported-by: Alexander Lakhin
Author: Hayato Kuroda
Reviewed-by: Alexander Lakhin, Amit Kapila
Discussion: http://postgr.es/m/62ed1a9f-746a-8e86-904b-51b9b806a1d9@gmail.com
Quotes are applied to GUCs in a very inconsistent way across the code
base, with a mix of double quotes or no quotes used. This commit
removes double quotes around all the GUC names that are obviously
referred to as parameters with non-English words (use of underscore,
mixed case, etc).
This is the result of a discussion with Álvaro Herrera, Nathan Bossart,
Laurenz Albe, Peter Eisentraut, Tom Lane and Daniel Gustafsson.
Author: Peter Smith
Discussion: https://postgr.es/m/CAHut+Pv-kSN8SkxSdoHano_wPubqcg5789ejhCDZAcLFceBR-w@mail.gmail.com
Switch from using TransactionId to FullTransactionId in naming of 2PC files.
Transaction state file in the pg_twophase directory now have extra 8 bytes in
the name to address an epoch of a given xid.
Author: Maxim Orlov, Aleksander Alekseev, Alexander Korotkov, Teodor Sigaev
Author: Nikita Glukhov, Pavel Borisov, Yura Sokolov
Reviewed-by: Jacob Champion, Heikki Linnakangas, Alexander Korotkov
Reviewed-by: Japin Li, Pavel Borisov, Tom Lane, Peter Eisentraut, Andres Freund
Reviewed-by: Andrey Borodin, Dilip Kumar, Aleksander Alekseev
Discussion: https://postgr.es/m/CACG%3DezZe1NQSCnfHOr78AtAZxJZeCvxrts0ygrxYwe%3DpyyjVWA%40mail.gmail.com
Discussion: https://postgr.es/m/CAJ7c6TPDOYBYrnCAeyndkBktO0WG2xSdYduTF0nxq%2BvfkmTF5Q%40mail.gmail.com
We've had repeated bugs in the area of handling SLRU wraparound in the past,
some of which have caused data loss. Switching to an indexing system for SLRUs
that does not wrap around should allow us to get rid of a whole bunch
of problems and improve the overall reliability of the system.
This particular patch however only changes the indexing and doesn't address
the wraparound per se. This is going to be done in the following patches.
Author: Maxim Orlov, Aleksander Alekseev, Alexander Korotkov, Teodor Sigaev
Author: Nikita Glukhov, Pavel Borisov, Yura Sokolov
Reviewed-by: Jacob Champion, Heikki Linnakangas, Alexander Korotkov
Reviewed-by: Japin Li, Pavel Borisov, Tom Lane, Peter Eisentraut, Andres Freund
Reviewed-by: Andrey Borodin, Dilip Kumar, Aleksander Alekseev
Discussion: https://postgr.es/m/CACG%3DezZe1NQSCnfHOr78AtAZxJZeCvxrts0ygrxYwe%3DpyyjVWA%40mail.gmail.com
Discussion: https://postgr.es/m/CAJ7c6TPDOYBYrnCAeyndkBktO0WG2xSdYduTF0nxq%2BvfkmTF5Q%40mail.gmail.com
If the tuple being updated is not visible to the crosscheck snapshot,
we return TM_Updated but the assertions would not hold in that case.
Move them to before the cross-check.
Fixes bug #17893. Backpatch to all supported versions.
Author: Alexander Lakhin
Backpatch-through: 12
Discussion: https://www.postgresql.org/message-id/17893-35847009eec517b5%40postgresql.org
Fix a bug introduced by c1ec02be1d. It may happen that the executor
opens indexes on the result relation, but no rows end up being inserted.
Then the index_insert_cleanup still gets executed, but passes down NULL
to the AM callback. The AM callback may not expect this, as is the case
of brininsertcleanup, leading to a crash.
Fixed by only calling the cleanup callback if (ii_AmCache != NULL). This
way the AM can simply assume to only see a valid cache.
Reported-by: Richard Guo
Discussion: https://postgr.es/m/CAMbWs4-w9qC-o9hQox9UHvdVZAYTp8OrPQOKtwbvzWaRejTT=Q@mail.gmail.com
XLogSetAsyncXactLSN(), called at asynchronous commit, would wake up
walwriter every time the LSN advances, but walwriter doesn't actually
do anything unless it has at least 'wal_writer_flush_after' full
blocks of WAL to write. Repeatedly waking up walwriter to do nothing
is a waste of CPU cycles in both walwriter and the backends doing the
wakeups. To fix, apply the same logic in XLogSetAsyncXactLSN() to
decide whether to wake up walwriter, as walwriter uses to determine if
it has any work to do.
In the passing, rename misleadingly named 'flushbytes' local variable
to 'flushblocks'.
Author: Andres Freund, Heikki Linnakangas
Discussion: https://www.postgresql.org/message-id/20231024230929.vsc342baqs7kmbte@awork3.anarazel.de
The brininsert code used to initialize (and destroy) BrinDesc and
BrinRevmap for each tuple, which is not free. This patch initializes
these structures only once, and reuses them for all inserts in the same
command. The data is passed through indexInfo->ii_AmCache.
This also introduces an optional AM callback "aminsertcleanup" that
allows performing custom cleanup in case simply pfree-ing ii_AmCache is
not sufficient (which is the case when the cache contains TupleDesc,
Buffers, and so on).
Author: Soumyadeep Chakraborty
Reviewed-by: Alvaro Herrera, Matthias van de Meent, Tomas Vondra
Discussion: https://postgr.es/m/CAE-ML%2B9r2%3DaO1wwji1sBN9gvPz2xRAtFUGfnffpd0ZqyuzjamA%40mail.gmail.com
When there are no indexes on a table, we vacuum each heap block after
pruning it and then update the freespace map. Periodically, we also
vacuum the freespace map. This was done while unnecessarily holding a
lock on the heap page. Release the lock before calling
FreeSpaceMapVacuumRange() and, while we're at it, ensure the range
includes the heap block we just vacuumed.
There are no known deadlocks or other similar issues, therefore don't
backpatch. It's certainly not good to do all this work under a lock, but it's
not frequently reached, making it not worth the risk of backpatching.
Author: Melanie Plageman <melanieplageman@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CAAKRu_YiL%3D44GvGnt1dpYouDSSoV7wzxVoXs8m3p311rp-TVQQ%40mail.gmail.com
As of commit eaa5808e8e, MemoryContextResetAndDeleteChildren() is
just a backwards compatibility macro for MemoryContextReset(). Now
that some time has passed, this macro seems more likely to create
confusion.
This commit removes the macro and replaces all remaining uses with
calls to MemoryContextReset(). Any third-party code that use this
macro will need to be adjusted to call MemoryContextReset()
instead. Since the two have behaved the same way since v9.5, such
adjustments won't produce any behavior changes for all
currently-supported versions of PostgreSQL.
Reviewed-by: Amul Sul, Tom Lane, Alvaro Herrera, Dagfinn Ilmari Mannsåker
Discussion: https://postgr.es/m/20231113185950.GA1668018%40nathanxps13
Alexander reported a crash with repeated create + drop database, after
the ResourceOwner rewrite (commit b8bff07daa). That was fixed by the
previous commit, but it nevertheless seems like a good idea clear
CurrentResourceOwner earlier, because you're not supposed to use it
for anything after we start releasing it.
Reviewed-by: Alexander Lakhin
Discussion: https://www.postgresql.org/message-id/11b70743-c5f3-3910-8e5b-dd6c115ff829%40gmail.com
It's clearly stated in the comments that ginFindParents() must keep
the pin on the index's root page that's associated with the topmost
GinBtreeStack item. However, the code path for the case that the
desired downlink has been pushed down to the next index level
ignored this proviso, and would release the pin anyway if we were
still examining the root level. That led to an assertion failure
or "buffer NNNN is not owned by resource owner" error later, when
we try to release the pin again at the end of the insertion.
This is quite hard to reproduce, since it can only happen if an
index root page split occurs concurrently with our own insertion.
Thanks to Jeff Janes for finding a test case that triggers it
often enough to allow investigation.
This has been there since the beginning of GIN, so back-patch
to all supported branches.
Discussion: https://postgr.es/m/CAMkU=1yCAKtv86dMrD__Ja-7KzjE=uMeKX8y__cx5W-OEWy2ow@mail.gmail.com
Commit 00d7fb5e2e started to use REGBUF_NO_CHANGE at a few places in the
code where we register the buffer before marking it dirty but missed
updating one of the code flows in the hash index where we free the overflow
page without any live tuples on it.
Author: Amit Kapila and Hayato Kuroda
Discussion: http://postgr.es/m/f045c8f7-ee24-ead6-3679-c04a43d21351@gmail.com
We don't want existing slots in the old cluster to get invalidated during
the upgrade. During an upgrade, we set this variable to -1 via the command
line in an attempt to prevent such invalidations, but users have ways to
override it. This patch ensures the value is not overridden by the user.
Author: Kyotaro Horiguchi
Reviewed-by: Peter Smith, Alvaro Herrera
Discussion: http://postgr.es/m/20231027.115759.2206827438943188717.horikyota.ntt@gmail.com
Instead of having a separate array/hash for each resource kind, use a
single array and hash to hold all kinds of resources. This makes it
possible to introduce new resource "kinds" without having to modify
the ResourceOwnerData struct. In particular, this makes it possible
for extensions to register custom resource kinds.
The old approach was to have a small array of resources of each kind,
and if it fills up, switch to a hash table. The new approach also uses
an array and a hash, but now the array and the hash are used at the
same time. The array is used to hold the recently added resources, and
when it fills up, they are moved to the hash. This keeps the access to
recent entries fast, even when there are a lot of long-held resources.
All the resource-specific ResourceOwnerEnlarge*(),
ResourceOwnerRemember*(), and ResourceOwnerForget*() functions have
been replaced with three generic functions that take resource kind as
argument. For convenience, we still define resource-specific wrapper
macros around the generic functions with the old names, but they are
now defined in the source files that use those resource kinds.
The release callback no longer needs to call ResourceOwnerForget on
the resource being released. ResourceOwnerRelease unregisters the
resource from the owner before calling the callback. That needed some
changes in bufmgr.c and some other files, where releasing the
resources previously always called ResourceOwnerForget.
Each resource kind specifies a release priority, and
ResourceOwnerReleaseAll releases the resources in priority order. To
make that possible, we have to restrict what you can do between
phases. After calling ResourceOwnerRelease(), you are no longer
allowed to remember any more resources in it or to forget any
previously remembered resources by calling ResourceOwnerForget. There
was one case where that was done previously. At subtransaction commit,
AtEOSubXact_Inval() would handle the invalidation messages and call
RelationFlushRelation(), which temporarily increased the reference
count on the relation being flushed. We now switch to the parent
subtransaction's resource owner before calling AtEOSubXact_Inval(), so
that there is a valid ResourceOwner to temporarily hold that relcache
reference.
Other end-of-xact routines make similar calls to AtEOXact_Inval()
between release phases, but I didn't see any regression test failures
from those, so I'm not sure if they could reach a codepath that needs
remembering extra resources.
There were two exceptions to how the resource leak WARNINGs on commit
were printed previously: llvmjit silently released the context without
printing the warning, and a leaked buffer io triggered a PANIC. Now
everything prints a WARNING, including those cases.
Add tests in src/test/modules/test_resowner.
Reviewed-by: Aleksander Alekseev, Michael Paquier, Julien Rouhaud
Reviewed-by: Kyotaro Horiguchi, Hayato Kuroda, Álvaro Herrera, Zhihong Yu
Reviewed-by: Peter Eisentraut, Andres Freund
Discussion: https://www.postgresql.org/message-id/cbfabeb0-cd3c-e951-a572-19b365ed314d%40iki.fi
false_positive_rate is a parameter that can be set with the bloom
opclass in BRIN, and setting it to a value of exactly 0.25 would trigger
an assertion in the first INSERT done on the index with value set.
The assertion changed here relied on BLOOM_{MIN|MAX}_FALSE_POSITIVE_RATE
that are somewhat arbitrary values, and specifying an out-of-range value
would also trigger a failure when defining such an index. So, as-is,
the assertion was just doubling on the min-max check of the reloption.
This is now enlarged to check that it is a correct percentage value,
instead, based on a suggestion by Tom Lane.
Author: Alexander Lakhin
Reviewed-by: Tom Lane, Shihao Zhong
Discussion: https://postgr.es/m/17969-a6c54de48026d694@postgresql.org
Backpatch-through: 14
pgstatindex failed with ERRCODE_DATA_CORRUPTED, of the "can't-happen"
class XX. The other functions succeeded on an empty index; they might
have malfunctioned if the failed index build left torn I/O or other
complex state. Report an ERROR in statistics functions pgstatindex,
pgstatginindex, pgstathashindex, and pgstattuple. Report DEBUG1 and
skip all index I/O in maintenance functions brin_desummarize_range,
brin_summarize_new_values, brin_summarize_range, and
gin_clean_pending_list. Back-patch to v11 (all supported versions).
Discussion: https://postgr.es/m/20231001195309.a3@google.com
When beginning recovery, a LOG is displayed by the startup process to
show which recovery mode will be used depending on the .signal file(s)
set in the data folder, like "standby mode", recovery up to a given
target type and value, or archive recovery.
A different patch is under discussion to simplify the startup code by
requiring the presence of recovery.signal and/or standby.signal when a
backup_label file is read. Delaying a bit this LOG ensures that the
correct recovery mode would be reported, and putting it at this position
does not make it lose its value.
While on it, this commit adds a few comments documenting a bit more the
initial recovery steps and their dependencies, and fixes an incorrect
comment format. This introduces no behavior changes.
Extracted from a larger patch by me.
Reviewed-by: David Steele, Bowen Shi
Discussion: https://postgr.es/m/ZArVOMifjzE7f8W7@paquier.xyz
When beginning recovery from a base backup by reading a backup_label
file, it may be possible that no checkpoint record is available
depending on the method used when the case backup was taken, which would
prevent recovery from beginning. In this case, the FATAL messages
issued, initially added by c900c15269, mentioned recovery.signal as
an option to do recovery but not standby.signal. Let's add it as an
available option, for clarity.
Per suggestion from Bowen Shi, extracted from a larger patch by me.
Author: Michael Paquier
Discussion: https://postgr.es/m/CAM_vCudkSjr7NsNKSdjwtfAm9dbzepY6beZ5DP177POKy8=2aw@mail.gmail.com
Historically, the statistics of the checkpointer have been always part
of pg_stat_bgwriter. This commit removes a few columns from
pg_stat_bgwriter, and introduces pg_stat_checkpointer with equivalent,
renamed columns (plus a new one for the reset timestamp):
- checkpoints_timed -> num_timed
- checkpoints_req -> num_requested
- checkpoint_write_time -> write_time
- checkpoint_sync_time -> sync_time
- buffers_checkpoint -> buffers_written
The fields of PgStat_CheckpointerStats and its SQL functions are renamed
to match with the new field names, for consistency. Note that
background writer and checkpointer have been split into two different
processes in commits 806a2aee37 and bf405ba8e4. The pgstat
structures were already split, making this change straight-forward.
Bump catalog version.
Author: Bharath Rupireddy
Reviewed-by: Bertrand Drouvot, Andres Freund, Michael Paquier
Discussion: https://postgr.es/m/CALj2ACVxX2ii=66RypXRweZe2EsBRiPMj0aHfRfHUeXJcC7kHg@mail.gmail.com
When calculating distance for interval values, the code mostly mimicked
interval_mi, i.e. it built a new interval value for the difference.
That however does not work for sufficiently distant interval values,
when the difference overflows the interval range.
Instead, we can calculate the distance directly, without constructing
the intermediate (and unnecessary) interval value.
Backpatch to 14, where minmax-multi indexes were introduced.
Reported-by: Dean Rasheed
Reviewed-by: Ashutosh Bapat, Dean Rasheed
Backpatch-through: 14
Discussion: https://postgr.es/m/eef0ea8c-4aaa-8d0d-027f-58b1f35dd170@enterprisedb.com
Make sure that infinite values in date/timestamp columns are treated as
if in infinite distance. Infinite values should not be merged with other
values, leaving them as outliers. The code however returned distance 0
in this case, so that infinite values were merged first. While this does
not break the index (i.e. it still produces correct query results), it
may make it much less efficient.
We don't need explicit handling of infinite date/timestamp values when
calculating distances, because those values are represented as extreme
but regular values (e.g. INT64_MIN/MAX for the timestamp type).
We don't need an exact distance, just a value that is much larger than
distanced between regular values. With the added cast to double values,
we can simply subtract the values.
The regression test queries a value in the "gap" and checks the range
was properly eliminated by the BRIN index.
This only affects minmax-multi indexes on timestamp/date columns with
infinite values, which is not very common in practice. The affected
indexes may need to be rebuilt.
Backpatch to 14, where minmax-multi indexes were introduced.
Reported-by: Ashutosh Bapat
Reviewed-by: Ashutosh Bapat, Dean Rasheed
Backpatch-through: 14
Discussion: https://postgr.es/m/eef0ea8c-4aaa-8d0d-027f-58b1f35dd170@enterprisedb.com
When calculating the distance between date values, make sure to subtract
them in the right order, i.e. (larger - smaller).
The distance is used to determine which values to merge, and is expected
to be a positive value. The code unfortunately did the subtraction in
the opposite order, i.e. (smaller - larger), thus producing negative
values and merging values the most distant values first.
The resulting index is correct (i.e. produces correct results), but may
be significantly less efficient. This affects all minmax-multi indexes
on date columns.
Backpatch to 14, where minmax-multi indexes were introduced.
Reported-by: Ashutosh Bapat
Reviewed-by: Ashutosh Bapat, Dean Rasheed
Backpatch-through: 14
Discussion: https://postgr.es/m/eef0ea8c-4aaa-8d0d-027f-58b1f35dd170@enterprisedb.com
When calculating distances for timestamp values for BRIN minmax-multi
indexes, we need to be careful about overflows for extreme values. If
the value overflows into a negative value, the index may be inefficient.
The new regression test checks this for the timestamp type by adding a
table with enough values to force range compaction/merging. The values
are close to min/max, which means a risk of overflow.
Fixed by converting the int64 values to double first, before calculating
the distance. This prevents the overflow. We may lose some precision, of
course, but that's good enough. In the worst case we build a slightly
less efficient index, but for large distances this won't matter.
This only affects minmax-multi indexes on timestamp columns, with ranges
containing values sufficiently distant to cause an overflow. That seems
like a fairly rare case in practice.
Backpatch to 14, where minmax-multi indexes were introduced.
Reported-by: Ashutosh Bapat
Reviewed-by: Ashutosh Bapat, Dean Rasheed
Backpatch-through: 14
Discussion: https://postgr.es/m/eef0ea8c-4aaa-8d0d-027f-58b1f35dd170@enterprisedb.com
Since C99, there can be a trailing comma after the last value in an
enum definition. A lot of new code has been introducing this style on
the fly. Some new patches are now taking an inconsistent approach to
this. Some add the last comma on the fly if they add a new last
value, some are trying to preserve the existing style in each place,
some are even dropping the last comma if there was one. We could
nudge this all in a consistent direction if we just add the trailing
commas everywhere once.
I omitted a few places where there was a fixed "last" value that will
always stay last. I also skipped the header files of libpq and ecpg,
in case people want to use those with older compilers. There were
also a small number of cases where the enum type wasn't used anywhere
(but the enum values were), which ended up confusing pgindent a bit,
so I left those alone.
Discussion: https://www.postgresql.org/message-id/flat/386f8c45-c8ac-4681-8add-e3b0852c1620%40eisentraut.org
Enforce the rule from transam/README in XLogRegisterBuffer(), and
update callers to follow the rule.
Hash indexes sometimes register clean pages as a part of the locking
protocol, so provide a REGBUF_NO_CHANGE flag to support that use.
Discussion: https://postgr.es/m/c84114f8-c7f1-5b57-f85a-3adc31e1a904@iki.fi
Reviewed-by: Heikki Linnakangas
This shouldn't change behavior except in the unusual case where
there are file in the tablespace directory that have entirely
numeric names but are nevertheless not possible names for a
tablespace directory, either because their names have leading zeroes
that shouldn't be there, or the value is actually zero, or because
the value is too large to represent as an OID.
In those cases, the directory would previously have made it into
the list of tablespaceinfo objects and no longer will. Thus, base
backups will now ignore such directories, instead of treating them
as legitimate tablespace directories. Similarly, if entries for
such tablespaces occur in a tablespace_map file, they will now
be rejected as erroneous, instead of being honored.
This is infrastructure for future work that wants to be able to
know the tablespace of each relation that is part of a backup
*as an OID*. By strengthening the up-front validation, we don't
have to worry about weird cases later, and can more easily avoid
repeated string->integer conversions.
Patch by me, reviewed by David Steele.
Discussion: http://postgr.es/m/CA+TgmoZNVeBzoqDL8xvr-nkaepq815jtDR4nJzPew7=3iEuM1g@mail.gmail.com
This allows tools that read the WAL sequentially to identify (possible)
redo points when they're reached, rather than only being able to
detect them in retrospect when XLOG_CHECKPOINT_ONLINE is found, possibly
much later in the WAL stream. There are other possible applications as
well; see the discussion links below.
Any redo location that precedes the checkpoint location should now point
to an XLOG_CHECKPOINT_REDO record, so add a cross-check to verify this.
While adjusting the code in CreateCheckPoint() for this patch, I made it
call WALInsertLockAcquireExclusive a bit later than before, since there
appears to be no need for it to be held while checking whether the system
is idle, whether this is an end-of-recovery checkpoint, or what the current
timeline is.
Bump XLOG_PAGE_MAGIC.
Patch by me, based in part on earlier work from Dilip Kumar. Review by
Dilip Kumar, Amit Kapila, Andres Freund, and Michael Paquier.
Discussion: http://postgr.es/m/CA+TgmoYy-Vc6G9QKcAKNksCa29cv__czr+N9X_QCxEfQVpp_8w@mail.gmail.com
Discussion: http://postgr.es/m/20230614194717.jyuw3okxup4cvtbt%40awork3.anarazel.de
Discussion: http://postgr.es/m/CA+hUKG+b2ego8=YNW2Ohe9QmSiReh1-ogrv8V_WZpJTqP3O+2w@mail.gmail.com
First, we shouldn't recommend switching to single-user mode, because
that's terrible advice. Especially on newer versions where VACUUM
will enter emergency mode when nearing (M)XID exhaustion, it's
perfectly fine to just VACUUM in multi-user mode. Doing it that way
is less disruptive and avoids disabling the safeguards that prevent
actual wraparound, so recommend that instead.
Second, be more precise about what is going to happen (when we're
nearing the limits) or what is happening (when we actually hit them).
The database doesn't shut down, nor does it refuse all commands. It
refuses commands that assign whichever of XIDs and MXIDs are nearly
exhausted.
No back-patch. The existing hint that advises going to single-user
mode is sufficiently awful advice that removing it or changing it
might be justifiable even though we normally avoid changing
user-facing messages in back-branches, but I (rhaas) felt that it
was better to be more conservative and limit this fix to master
only. Aside from the usual risk of breaking translations, people
might be used to the existing message, or even have monitoring
scripts that look for it.
Alexander Alekseev, John Naylor, Robert Haas, reviewed at various
times by Peter Geoghegan, Hannu Krosing, and Andres Freund.
Discussion: http://postgr.es/m/CA+TgmoZBg95FiR9wVQPAXpGPRkacSt2okVge+PKPPFppN7sfnQ@mail.gmail.com
The word "assign" is used in various places internally to describe what
GetNewMultiXactId does, but the user-facing messages have previously
said "generate". For consistency, standardize on "assign," which seems
(at least to me) to be slightly clearer.
Discussion: http://postgr.es/m/CA+TgmoaoE1_i3=4-7GCTtKLVZVQ2Gh6qESW2VG1OprtycxOHMA@mail.gmail.com
If SIGTERM is received within this section, the startup process
will immediately proc_exit() in the signal handler, so it is
inadvisable to include any more code than is required there (as
such code is unlikely to be compatible with doing proc_exit() in a
signal handler). This commit moves the code recently added to this
section (see 1b06d7bac9 and 7fed801135) to outside of the section.
This ensures that the startup process only calls proc_exit() in its
SIGTERM handler for the duration of the system() call, which is how
this code worked from v8.4 to v14.
Reported-by: Michael Paquier, Thomas Munro
Analyzed-by: Andres Freund
Suggested-by: Tom Lane
Reviewed-by: Michael Paquier, Robert Haas, Thomas Munro, Andres Freund
Discussion: https://postgr.es/m/Y9nGDSgIm83FHcad%40paquier.xyz
Discussion: https://postgr.es/m/20230223231503.GA743455%40nathanxps13
Backpatch-through: 15
When COPYing into a partitioned table that does now permit the use of
table_multi_insert(), we could error out with
ERROR: could not read block NN in file "base/...": read only 0 of 8192 bytes
because BulkInsertState->next_free was not reset between partitions. This
problem occurred only when not able to use table_multi_insert(), as a
dedicated BulkInsertState for each partition is used in that case.
The bug was introduced in 00d1e02be2, but it was hard to hit at that point,
as commonly bulk relation extension is not used when not using
table_multi_insert(). It became more likely after 82a4edabd2, which expanded
the use of bulk extension.
To fix the bug, reset the bulk relation extension state in BulkInsertState in
ReleaseBulkInsertStatePin(). That was added (in b1ecb9b3fc) to tackle a very
similar issue. Obviously the name is not quite correct, but there might be
external callers, and bulk insert state needs to be reset in precisely in the
situations that ReleaseBulkInsertStatePin() already needed to be called.
Medium term the better fix likely is to disallow reusing BulkInsertState
across relations.
Add a test that, without the fix, reproduces #18130 in most
configurations. The test also catches the problem fixed in b1ecb9b3fc when
run with small shared_buffers.
Reported-by: Ivan Kolombet <enderstd@gmail.com>
Analyzed-by: Tom Lane <tgl@sss.pgh.pa.us>
Analyzed-by: Andres Freund <andres@anarazel.de>
Bug: #18130
Discussion: https://postgr.es/m/18130-7a86a7356a75209d%40postgresql.org
Discussion: https://postgr.es/m/257696.1695670946%40sss.pgh.pa.us
Backpatch: 16-
* sync_method is renamed to wal_sync_method.
* sync_method_options[] is renamed to wal_sync_method_options[].
* assign_xlog_sync_method() is renamed to assign_wal_sync_method().
* The names of the available synchronization methods are now
prefixed with "WAL_SYNC_METHOD_" and have been moved into a
WalSyncMethod enum.
* PLATFORM_DEFAULT_SYNC_METHOD is renamed to
PLATFORM_DEFAULT_WAL_SYNC_METHOD, and DEFAULT_SYNC_METHOD is
renamed to DEFAULT_WAL_SYNC_METHOD.
These more descriptive names help distinguish the code for
wal_sync_method from the code for DataDirSyncMethod (e.g., the
recovery_init_sync_method configuration parameter and the
--sync-method option provided by several frontend utilities). This
change also prevents name collisions between the aforementioned
sets of code. Since this only improves the naming of internal
identifiers, there should be no behavior change.
Author: Maxim Orlov
Discussion: https://postgr.es/m/CACG%3DezbL1gwE7_K7sr9uqaCGkWhmvRTcTEnm3%2BX1xsRNwbXULQ%40mail.gmail.com
When MyProc->delayChkptFlags is set to temporarily block phase
transitions in a concurrent checkpoint, the checkpointer enters a
sleep-poll loop to wait for the flag to be cleared. We should show that
as a wait event in the pg_stat_activity view.
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CA%2BhUKGL7Whi8iwKbzkbn_1fixH3Yy8aAPz7mfq6Hpj7FeJrKMg%40mail.gmail.com
An upcoming patch wants to introduce an additional special case in
this function. To keep that as cheap as possible, minimize the amount
of branching that we do based on whether this is an XLOG_SWITCH
record.
Additionally, and also in the interest of keeping the overhead of
special-case code paths as low as possible, apply likely() to the
non-XLOG_SWITCH case, since only a very tiny fraction of WAL records
will be XLOG_SWITCH records.
Patch by me, reviewed by Dilip Kumar, Amit Kapila, Andres Freund,
and Michael Paquier.
Discussion: http://postgr.es/m/CA+TgmoYy-Vc6G9QKcAKNksCa29cv__czr+N9X_QCxEfQVpp_8w@mail.gmail.com
Currently, B-tree code matches every scan key to every item on the page.
Imagine the ordered B-tree scan for the query like this.
SELECT * FROM tbl WHERE col > 'a' AND col < 'b' ORDER BY col;
The (col > 'a') scan key will be always matched once we find the location to
start the scan. The (col < 'b') scan key will match every item on the page
as long as it matches the last item on the page.
This patch implements prechecking of the scan keys required for directional
scan on beginning of page scan. If precheck is successful we can skip this
scan keys check for the items on the page. That could lead to significant
acceleration especially if the comparison operator is expensive.
Idea from patch by Konstantin Knizhnik.
Discussion: https://postgr.es/m/079c3f8e-3371-abe2-e93c-fc8a0ae3f571%40garret.ru
Reviewed-by: Peter Geoghegan, Pavel Borisov
BuildDescForRelation() main job is to convert ColumnDef lists to
pg_attribute/tuple descriptor arrays, which is really mostly an
internal subroutine of DefineRelation() and some related functions,
which is more the remit of tablecmds.c and doesn't have much to do
with the basic tuple descriptor interfaces in tupdesc.c. This is also
supported by observing the header includes we can remove in tupdesc.c.
By moving it over, we can also (in the future) make
BuildDescForRelation() use more internals of tablecmds.c that are not
sensible to be exposed in tupdesc.c.
Discussion: https://www.postgresql.org/message-id/flat/52a125e4-ff9a-95f5-9f61-b87cf447e4da@eisentraut.org
Make a few newish calls to appendStringInfo() which have no special
formatting use appendStringInfoString() instead. Also, adjust usages of
appendStringInfoString() which only append a string containing a single
character to make use of appendStringInfoChar() instead.
This makes the code marginally faster, but primarily this change is so
we use the StringInfo type as it was intended to be used.
Discussion: https://postgr.es/m/CAApHDvpXKQmL+r=VDNS98upqhr9yGBhv2Jw3GBFFk_wKHcB39A@mail.gmail.com
This commit changes the WAL reader routines so as a FATAL for the
backend or exit(FAILURE) for the frontend is triggered if an allocation
for a WAL record decode fails in walreader.c, rather than treating this
case as bogus data, which would be equivalent to the end of WAL. The
key is to avoid palloc_extended(MCXT_ALLOC_NO_OOM) in walreader.c,
relying on plain palloc() calls.
The previous behavior could make WAL replay finish too early than it
should. For example, crash recovery finishing earlier may corrupt
clusters because not all the WAL available locally was replayed to
ensure a consistent state. Out-of-memory failures would show up
randomly depending on the memory pressure on the host, but one simple
case would be to generate a large record, then replay this record after
downsizing a host, as Ethan Mertz originally reported.
This relies on bae868caf2, as the WAL reader routines now do the
memory allocation required for a record only once its header has been
fully read and validated, making xl_tot_len trustable. Making the WAL
reader react differently on out-of-memory or bogus record data would
require ABI changes, so this is the safest choice for stable branches.
Also, it is worth noting that 3f1ce97346 has been using a plain
palloc() in this code for some time now.
Thanks to Noah Misch and Thomas Munro for the discussion.
Like the other commit, backpatch down to 12, leaving out v11 that will
be EOL'd soon. The behavior of considering a failed allocation as bogus
data comes originally from 0ffe11abd3, where the record length
retrieved from its header was not entirely trustable.
Reported-by: Ethan Mertz
Discussion: https://postgr.es/m/ZRKKdI5-RRlta3aF@paquier.xyz
Backpatch-through: 12
The retry loop is needed because heap_page_prune() calls
HeapTupleSatisfiesVacuum() and then lazy_scan_prune() does the same
thing again, and they might get different answers due to concurrent
clog updates. But this patch makes heap_page_prune() return the
HeapTupleSatisfiesVacuum() results that it computed back to the
caller, which allows lazy_scan_prune() to avoid needing to recompute
those values in the first place. That's nice both because it eliminates
the need for a retry loop and also because it's cheaper.
Melanie Plageman, reviewed by David Geier, Andres Freund, and me.
Discussion: https://postgr.es/m/CAAKRu_br124qsGJieuYA0nGjywEukhK1dKBfRdby_4yY3E9SXA%40mail.gmail.com
nbtree's mark/restore processing failed to correctly handle an edge case
involving array key advancement and related search-type scan key state.
Scans with ScalarArrayScalarArrayOpExpr quals requiring mark/restore
processing (for a merge join) could incorrectly conclude that an
affected array/scan key must not have advanced during the time between
marking and restoring the scan's position.
As a result of all this, array key handling within btrestrpos could skip
a required call to _bt_preprocess_keys(). This confusion allowed later
primitive index scans to overlook tuples matching the true current array
keys. The scan's search-type scan keys would still have spurious values
corresponding to the final array element(s) -- not values matching the
first/now-current array element(s).
To fix, remember that "array key wraparound" has taken place during the
ongoing btrescan in a flag variable stored in the scan's state, and use
that information at the point where btrestrpos decides if another call
to _bt_preprocess_keys is required.
Oversight in commit 70bc5833, which taught nbtree to handle array keys
during mark/restore processing, but missed this subtlety. That commit
was itself a bug fix for an issue in commit 9e8da0f7, which taught
nbtree to handle ScalarArrayOpExpr quals natively.
Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-WzkgP3DDRJxw6DgjCxo-cu-DKrvjEv_ArkP2ctBJatDCYg@mail.gmail.com
Backpatch: 11- (all supported branches).
Previously, one of the values in the struct was returned as the return
value, and another was returned via an output parameter. In
preparation for returning more stuff, consolidate both values into a
struct returned via an output parameter.
Melanie Plageman, reviewed by Andres Freund and by me.
Discussion: https://postgr.es/m/CAAKRu_br124qsGJieuYA0nGjywEukhK1dKBfRdby_4yY3E9SXA%40mail.gmail.com
This unifies some repetitive code.
Note: I didn't push the "not found" error message into the new
function, even though all existing callers would be able to make use
of it. Using the existing error handling as-is would probably require
exposing the Relation type via tupdesc.h, which doesn't seem
desirable. (Or even if we changed it to just report the OID, it would
inject the concept of a relation containing the tuple descriptor into
tupdesc.h, which might be a layering violation. Perhaps some further
improvements could be considered here separately.)
Discussion: https://www.postgresql.org/message-id/flat/52a125e4-ff9a-95f5-9f61-b87cf447e4da%40eisentraut.org
Yet another bug in the ilk of commits a7ee7c851 and 741b88435. In
741b88435, we took care to clear the memorized location of the
downlink when we split the parent page, because splitting the parent
page can move the downlink. But we missed that even *updating* a tuple
on the parent can move it, because updating a tuple on a gist page is
implemented as a delete+insert, so the updated tuple gets moved to the
end of the page.
This commit fixes the bug in two different ways (belt and suspenders):
1. Clear the downlink when we update a tuple on the parent page, even
if it's not split. This the same approach as in commits a7ee7c851
and 741b88435.
I also noticed that gistFindCorrectParent did not clear the
'downlinkoffnum' when it stepped to the right sibling. Fix that
too, as it seems like a clear bug even though I haven't been able
to find a test case to hit that.
2. Change gistFindCorrectParent so that it treats 'downlinkoffnum'
merely as a hint. It now always first checks if the downlink is
still at that location, and if not, it scans the page like before.
That's more robust if there are still more cases where we fail to
clear 'downlinkoffnum' that we haven't yet uncovered. With this,
it's no longer necessary to meticulously clear 'downlinkoffnum',
so this makes the previous fixes unnecessary, but I didn't revert
them because it still seems nice to clear it when we know that the
downlink has moved.
Also add the test case using the same test data that Alexander
posted. I tried to reduce it to a smaller test, and I also tried to
reproduce this with different test data, but I was not able to, so
let's just include what we have.
Backpatch to v12, like the previous fixes.
Reported-by: Alexander Lakhin
Discussion: https://www.postgresql.org/message-id/18129-caca016eaf0c3702@postgresql.org
bae868ca removed a check that was still needed. If you had an
xl_tot_len at the end of a page that was too small for a record header,
but not big enough to span onto the next page, we'd immediately perform
the CRC check using a bogus large length. Because of arbitrary coding
differences between the CRC implementations on different platforms,
nothing very bad happened on common modern systems. On systems using
the _sb8.c fallback we could segfault.
Restore that check, add a new assertion and supply a test for that case.
Back-patch to 12, like bae868ca.
Tested-by: Tom Lane <tgl@sss.pgh.pa.us>
Tested-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKGLCkTT7zYjzOxuLGahBdQ%3DMcF%3Dz5ZvrjSOnW4EDhVjT-g%40mail.gmail.com
xl_tot_len comes first in a WAL record. Usually we don't trust it to be
the true length until we've validated the record header. If the record
header was split across two pages, previously we wouldn't do the
validation until after we'd already tried to allocate enough memory to
hold the record, which was bad because it might actually be garbage
bytes from a recycled WAL file, so we could try to allocate a lot of
memory. Release 15 made it worse.
Since 70b4f82a4b, we'd at least generate an end-of-WAL condition if the
garbage 4 byte value happened to be > 1GB, but we'd still try to
allocate up to 1GB of memory bogusly otherwise. That was an
improvement, but unfortunately release 15 tries to allocate another
object before that, so you could get a FATAL error and recovery could
fail.
We can fix both variants of the problem more fundamentally using
pre-existing page-level validation, if we just re-order some logic.
The new order of operations in the split-header case defers all memory
allocation based on xl_tot_len until we've read the following page. At
that point we know that its first few bytes are not recycled data, by
checking its xlp_pageaddr, and that its xlp_rem_len agrees with
xl_tot_len on the preceding page. That is strong evidence that
xl_tot_len was truly the start of a record that was logged.
This problem was most likely to occur on a standby, because
walreceiver.c recycles WAL files without zeroing out trailing regions of
each page. We could fix that too, but it wouldn't protect us from rare
crash scenarios where the trailing zeroes don't make it to disk.
With reliable xl_tot_len validation in place, the ancient policy of
considering malloc failure to indicate corruption at end-of-WAL seems
quite surprising, but changing that is left for later work.
Also included is a new TAP test to exercise various cases of end-of-WAL
detection by writing contrived data into the WAL from Perl.
Back-patch to 12. We decided not to put this change into the final
release of 11.
Author: Thomas Munro <thomas.munro@gmail.com>
Author: Michael Paquier <michael@paquier.xyz>
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Reviewed-by: Noah Misch <noah@leadboat.com> (the idea, not the code)
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Sergei Kornilov <sk@zsrv.org>
Reviewed-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/17928-aa92416a70ff44a2%40postgresql.org
In older branches, COMMIT/ROLLBACK AND CHAIN failed to propagate
the current transaction's properties to the new transaction if
there was any open subtransaction (unreleased savepoint).
Instead, some previous transaction's properties would be restored.
This is because the "if (s->chain)" check in CommitTransactionCommand
examined the wrong instance of the "chain" flag and falsely
concluded that it didn't need to save transaction properties.
Our regression tests would have noticed this, except they used
identical transaction properties for multiple tests in a row,
so that the faulty behavior was not distinguishable from correct
behavior.
Commit 12d768e70 fixed the problem in v15 and later, but only rather
accidentally, because I removed the "if (s->chain)" test to avoid a
compiler warning, while not realizing that the warning was flagging a
real bug.
In v14 and before, remove the if-test and save transaction properties
unconditionally; just as in the newer branches, that's not expensive
enough to justify thinking harder.
Add the comment and extra regression test to v15 and later to
forestall any future recurrence, but there's no live bug in those
branches.
Patch by me, per bug #18118 from Liu Xiang. Back-patch to v12 where
the AND CHAIN feature was added.
Discussion: https://postgr.es/m/18118-4b72fcbb903aace6@postgresql.org
When tracking IO timing for WAL, the duration is what we calculate
based on the start and end timestamps, it's not what the variable
contains. Rename the timestamp variable to end to better communicate
what it contains. Original patch by Krishnakumar with additional
hacking to fix another occurrence by me.
Author: Krishnakumar R <kksrcv001@gmail.com>
Discussion: https://postgr.es/m/CAPMWgZ9f9o8awrQpjo8oxnNQ=bMDVPx00NE0QcDzvHD_ZrdLPw@mail.gmail.com
This became safe after commit 4b4798e138. The smgrcreate() call will
now register the segment for syncing at the next checkpoint, so we
don't need to sync it here. If a checkpoint happens before the
creation is WAL-logged, the records will be replayed when starting
recovery from the checkpoint. If a checkpoint happens after the WAL
logging, the checkpoint will fsync() it.
In the passing, clarify a comment in smgrDoPendingSyncs().
Discussion: https://www.postgresql.org/message-id/6e5bbc08-cdfc-b2b3-9e23-1a914b9850a9%40iki.fi
Reviewed-by: Robert Haas
The majority of all filenames are quoted in user facing error and
log messages, but a few were still printed without quotes. While
these filenames do not risk causing any ambiguity as their format
is strict, quote them anyways to be consistent across all logs.
Also concatenate a message to keep it one line to make it easier
to grep for in the code.
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/080EEABE-6645-4A46-AB20-6285ADAC44FE@yesql.se
It's entirely possible for a logical slot to have a confirmed_flush LSN
higher than the last value saved on disk while not being marked as dirty.
Currently, it is not a major problem but a later patch adding support for
the upgrade of slots relies on that value being properly flushed to disk.
It can also help avoid processing the same transactions again in some
boundary cases after the clean shutdown and restart. Say, we process
some transactions for which we didn't send anything downstream (the
changes got filtered) but the confirm_flush LSN is updated due to
keepalives. As we don't flush the latest value of confirm_flush LSN, it
may lead to processing the same changes again without this patch.
The approach taken by this patch has been suggested by Ashutosh Bapat.
Author: Vignesh C, Julien Rouhaud, Kuroda Hayato
Reviewed-by: Amit Kapila, Dilip Kumar, Michael Paquier, Ashutosh Bapat, Peter Smith, Hou Zhijie
Discussion: http://postgr.es/m/CAA4eK1JzJagMmb_E8D4au=GYQkxox0AfNBm1FbP7sy7t4YWXPQ@mail.gmail.com
Discussion: http://postgr.es/m/TYAPR01MB58664C81887B3AF2EB6B16E3F5939@TYAPR01MB5866.jpnprd01.prod.outlook.com
The comment in heapgettup_advance_block() says that it reports the
scan position before checking for end of scan, but that didn't match
the code. The code was refactored in commit 7ae0ab0ad9, which
inadvertently changed the order of the check and reporting. Change it
back.
This caused a few regression test failures with a small shared_buffers
setting like 10 MB. The 'portals' and 'cluster' tests perform seqscans
that are large enough that sync seqscans kick in. When the sync scan
position is not updated at end of scan, the next seq scan doesn't
start at the beginning of the table, and the test queries are
sensitive to that.
Reviewed-by: Melanie Plageman, David Rowley
Discussion: https://www.postgresql.org/message-id/6f991389-ae22-d844-a9d8-9aceb7c01a9a@iki.fi
Backpatch-through: 16
Since its introduction in 10074651e3, pg_promote() has been returning
a false status in three cases:
- SIGUSR1 not sent to the postmaster process.
- Postmaster death during standby promotion.
- Standby not promoted within the specified wait time.
An application calling this function will have a hard time understanding
what a false state returned actually means.
Per discussion, this switches the two first states to fail rather than
return a "false" status, making the second case more consistent with the
existing CHECK_FOR_INTERRUPTS in the wait loop. False is only returned
when the promotion is not completed within the specified time (60s by
default).
Author: Ashutosh Sharma
Reviewed-by: Fujii Masao, Laurenz Albe, Michael Paquier
Discussion: https://postgr.es/m/CAE9k0P=QTrwptL0t4J0fuBRDDjgsT-0PVKd-ikd96i1hyL7Bcg@mail.gmail.com
Make the primary messages more compact and make the detail messages
uniform. In initdb.c and pg_resetwal.c, use the newish
option_parse_int() to simplify some of the option parsing. For the
backend GUC wal_segment_size, add a GUC check hook to do the
verification instead of coding it in bootstrap.c. This might be
overkill, but that way the check is in the right place and it becomes
more self-documenting.
In passing, make pg_controldata use the logging API for warning
messages.
Reviewed-by: Aleksander Alekseev <aleksander@timescale.com>
Discussion: https://www.postgresql.org/message-id/flat/9939aa8a-d7be-da2c-7715-0a0b5535a1f7@eisentraut.org
Some of the ambuildempty functions used smgrwrite() directly, followed
by smgrimmedsync(). A few small problems with that:
Firstly, one is supposed to use smgrextend() when extending a
relation, not smgrwrite(). It doesn't make much difference in
production builds. smgrextend() updates the relation size cache, so
you miss that, but that's harmless because we never use the cached
relation size of an init fork. But if you compile with
CHECK_WRITE_VS_EXTEND, you get an assertion failure.
Secondly, the smgrwrite() calls were performed before WAL-logging, so
the page image written to disk had 0/0 as the LSN, not the LSN of the
WAL record. That's also harmless in practice, but seems sloppy.
Thirdly, it's better to use the buffer cache, because then you don't
need to smgrimmedsync() the relation to disk, which adds latency.
Bypassing the cache makes sense for bulk operations like index
creation, but not when you're just initializing an empty index.
Creation of unlogged tables is hardly performance bottleneck in any
real world applications, but nevertheless.
Backpatch to v16, but no further. These issues should be harmless in
practice, so better to not rock the boat in older branches.
Reviewed-by: Robert Haas
Discussion: https://www.postgresql.org/message-id/6e5bbc08-cdfc-b2b3-9e23-1a914b9850a9@iki.fi
This commit introduces descriptively-named macros for the
identifiers used in wire protocol messages. These new macros are
placed in a new header file so that they can be easily used by
third-party code.
Author: Dave Cramer
Reviewed-by: Alvaro Herrera, Tatsuo Ishii, Peter Smith, Robert Haas, Tom Lane, Peter Eisentraut, Michael Paquier
Discussion: https://postgr.es/m/CADK3HHKbBmK-PKf1bPNFoMC%2BoBt%2BpD9PH8h5nvmBQskEHm-Ehw%40mail.gmail.com
Commit 31966b15 invented a way for functions dealing with relation
extension to accept a Relation in online code and an SMgrRelation in
recovery code. It seems highly likely that future bufmgr.c interfaces
will face the same problem, and need to do something similar.
Generalize the names so that each interface doesn't have to re-invent
the wheel.
Back-patch to 16. Since extension AM authors might start using the
constructor macros once 16 ships, we agreed to do the rename in 16
rather than waiting for 17.
Reviewed-by: Peter Geoghegan <pg@bowt.ie>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA%2BhUKG%2B6tLD2BhpRWycEoti6LVLyQq457UL4ticP5xd8LqHySA%40mail.gmail.com
Attribute missing values might be needed past the lifetime of the tuple
descriptors from which they are extracted. To avoid possibly using
pointers for by-reference values which might thus be left dangling, we
cache a datumCopy'd version of the datum in the TopMemoryContext. Since
we first search for the value this only needs to be done once per
session for any such value.
Original complaint from Tom Lane, idea for mitigation by Andrew Dunstan,
tweaked by Tom Lane.
Backpatch to version 11 where missing values were introduced.
Discussion: https://postgr.es/m/1306569.1687978174@sss.pgh.pa.us
The new relation extension logic, introduced in 00d1e02be2, could lead to
slowdowns in some scenarios. E.g., when loading narrow rows into a table using
COPY, the caller of RelationGetBufferForTuple() will only request a small
number of pages. Without concurrency, we just extended using pwritev() in that
case. However, if there is *some* concurrency, we switched between extending
by a small number of pages and a larger number of pages, depending on the
number of waiters for the relation extension logic. However, some
filesystems, XFS in particular, do not perform well when switching between
extending files using fallocate() and pwritev().
To avoid that issue, remember the number of prior relation extensions in
BulkInsertState and extend more aggressively if there were prior relation
extensions. That not just avoids the aforementioned slowdown, but also leads
to noticeable performance gains in other situations, primarily due to
extending more aggressively when there is no concurrency. I should have done
it this way from the get go.
Reported-by: Masahiko Sawada <sawada.mshk@gmail.com>
Author: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CAD21AoDvDmUQeJtZrau1ovnT_smN940=Kp6mszNGK3bq9yRN6g@mail.gmail.com
Backpatch: 16-, where the new relation extension code was added
pg_logical_emit_message(false, '_', repeat('x', 1069547465)) failed with
self-contradictory message "WAL record would be 1069547520 bytes (of
maximum 1069547520 bytes)". There's no particular benefit from allowing
or denying one byte in either direction; XLogRecordMaxSize could rise a
few megabytes without trouble. Hence, this is just for cleanliness.
Back-patch to v16, where this check first appeared.
This commit adds a few comments about what LWLockWaitForVar() relies on
when a backend waits for a variable update on its LWLocks for WAL
insertions up to an expected LSN.
First, LWLockWaitForVar() does not include a memory barrier, relying on
a spinlock taken at the beginning of WaitXLogInsertionsToFinish(). This
was hidden behind two layers of routines in lwlock.c. This assumption
is now documented at the top of LWLockWaitForVar(), and detailed at bit
more within LWLockConflictsWithVar().
Second, document why WaitXLogInsertionsToFinish() does not include
memory barriers, relying on a spinlock at its top, which is, per Andres'
input, fine for two different reasons, both depending on the fact that
the caller of WaitXLogInsertionsToFinish() is waiting for a LSN up to a
certain value.
This area's documentation and assumptions could be improved more in the
future, but at least that's a beginning.
Author: Bharath Rupireddy, Andres Freund
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/CALj2ACVF+6jLvqKe6xhDzCCkr=rfd6upaGc3477Pji1Ke9G7Bg@mail.gmail.com
The WAL insertion lock variable insertingAt is currently being read
and written with the help of the LWLock wait list lock to avoid any read
of torn values. This wait list lock can become a point of contention on
a highly concurrent write workloads.
This commit switches insertingAt to a 64b atomic variable that provides
torn-free reads/writes. On platforms without 64b atomic support, the
fallback implementation uses spinlocks to provide the same guarantees
for the values read. LWLockWaitForVar(), through
LWLockConflictsWithVar(), reads the new value to check if it still needs
to wait with a u64 atomic operation. LWLockUpdateVar() updates the
variable before waking up the waiters with an exchange_u64 (full memory
barrier). LWLockReleaseClearVar() now uses also an exchange_u64 to
reset the variable. Before this commit, all these steps relied on
LWLockWaitListLock() and LWLockWaitListUnlock().
This reduces contention on LWLock wait list lock and improves
performance of highly-concurrent write workloads. Here are some
numbers using pg_logical_emit_message() (HEAD at d6677b93) with various
arbitrary record lengths and clients up to 1k on a rather-large machine
(64 vCPUs, 512GB of RAM, 16 cores per sockets, 2 sockets), in terms of
TPS numbers coming from pgbench:
message_size_b | 16 | 64 | 256 | 1024
--------------------+--------+--------+--------+-------
patch_4_clients | 83830 | 82929 | 80478 | 73131
patch_16_clients | 267655 | 264973 | 250566 | 213985
patch_64_clients | 380423 | 378318 | 356907 | 294248
patch_256_clients | 360915 | 354436 | 326209 | 263664
patch_512_clients | 332654 | 321199 | 287521 | 240128
patch_1024_clients | 288263 | 276614 | 258220 | 217063
patch_2048_clients | 252280 | 243558 | 230062 | 192429
patch_4096_clients | 212566 | 213654 | 205951 | 166955
head_4_clients | 83686 | 83766 | 81233 | 73749
head_16_clients | 266503 | 265546 | 249261 | 213645
head_64_clients | 366122 | 363462 | 341078 | 261707
head_256_clients | 132600 | 132573 | 134392 | 165799
head_512_clients | 118937 | 114332 | 116860 | 150672
head_1024_clients | 133546 | 115256 | 125236 | 151390
head_2048_clients | 137877 | 117802 | 120909 | 138165
head_4096_clients | 113440 | 115611 | 120635 | 114361
Bharath has been measuring similar improvements, where the limit of the
WAL insertion lock begins to be felt when more than 256 concurrent
clients are involved in this specific workload.
An extra patch has been discussed to introduce a fast-exit path in
LWLockUpdateVar() when there are no waiters, still this does not
influence the write-heavy workload cases discussed as there are always
waiters. This will be considered separately.
Author: Bharath Rupireddy
Reviewed-by: Nathan Bossart, Andres Freund, Michael Paquier
Discussion: https://postgr.es/m/CALj2ACVF+6jLvqKe6xhDzCCkr=rfd6upaGc3477Pji1Ke9G7Bg@mail.gmail.com
This has been missed in cb0cca1, noticed before buildfarm member koel
has been able to complain while poking at a different patch. Like the
other commit, backpatch all the way down to limit the odds of merge
conflicts.
Backpatch-through: 11
A crash in the middle of a checkpoint with some two-phase state data
already flushed to disk by this checkpoint could cause a follow-up crash
recovery to recover twice the same transaction, once from what has been
found in pg_twophase/ at the beginning of recovery and a second time
when replaying its corresponding record.
This would lead to FATAL failures in the startup process during
recovery, where the same transaction would have a state recovered twice
instead of once:
LOG: recovering prepared transaction 731 from shared memory
LOG: recovering prepared transaction 731 from shared memory
FATAL: lock ExclusiveLock on object 731/0/0 is already held
This issue is fixed by skipping the addition of any 2PC state coming
from a record whose equivalent 2PC state file has already been loaded in
TwoPhaseState at the beginning of recovery by restoreTwoPhaseData(),
which is OK as long as the system has not reached a consistent state.
The timing to get a messed up recovery processing is very racy, and
would very unlikely happen. The thread that has reported the issue has
demonstrated the bug using injection points to force a PANIC in the
middle of a checkpoint.
Issue introduced in 728bd99, so backpatch all the way down.
Reported-by: "suyu.cmj" <mengjuan.cmj@alibaba-inc.com>
Author: "suyu.cmj" <mengjuan.cmj@alibaba-inc.com>
Author: Michael Paquier
Discussion: https://postgr.es/m/109e6994-b971-48cb-84f6-829646f18b4c.mengjuan.cmj@alibaba-inc.com
Backpatch-through: 11
This commit adds two columns: indexes_total and indexes_processed, to
pg_stat_progress_vacuum system view to show the index vacuum
progress. These numbers are reported in the "vacuuming indexes" and
"cleaning up indexes" phases.
This uses the new parallel message type for progress reporting added
by be06506e7.
Bump catversion because this changes the definition of
pg_stat_progress_vacuum.
Author: Sami Imseih
Reviewed by: Masahiko Sawada, Michael Paquier, Nathan Bossart, Andres Freund
Discussion: https://www.postgresql.org/message-id/flat/5478DFCD-2333-401A-B2F0-0D186AB09228@amazon.com
This commit adds a new type of parallel message 'P' to allow a
parallel worker to poke at a leader to update the progress.
Currently it supports only incremental progress reporting but it's
possible to allow for supporting of other backend progress APIs in the
future.
There are no users of this new message type as of this commit. That
will follow in future commits.
Idea from Andres Freund.
Author: Sami Imseih
Reviewed by: Michael Paquier, Masahiko Sawada
Discussion: https://www.postgresql.org/message-id/flat/5478DFCD-2333-401A-B2F0-0D186AB09228@amazon.com
Commit 19d8e2308b allowed a weaker check for HOT with summarizing
indexes, but it did not update README.HOT. So do that now.
Patch by Matthias van de Meent, minor changes by me. Backpatch to 16,
where the optimization was introduced.
Author: Matthias van de Meent
Reviewed-by: Tomas Vondra
Backpatch-through: 16
Discussion: https://postgr.es/m/CAEze2WiEOm8V+c9kUeYp2BPhbEc5s473fUf51xNeqvSFGv44Ew@mail.gmail.com
The ginfast.c code previously checked for conflicts in before locking
the relevant buffer, leaving a window where a RW conflict could be
missed. Re-order.
There was also a place where buffer ID and block number were confused
while trying to predicate-lock a page, noted by visual inspection.
Back-patch to all supported releases. Fixes one more problem discovered
with the reproducer from bug #17949, in this case when Dmitry tried
other index types.
Reported-by: Artem Anisimov <artem.anisimov.255@gmail.com>
Reported-by: Dmitry Dolgov <9erthalion6@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Discussion: https://postgr.es/m/17949-a0f17035294a55e2%40postgresql.org
When performing a bitmap heap scan, we don't want to miss concurrent
writes that occurred after we observed the heap's rs_nblocks, but before
we took predicate locks on index pages. Therefore, we can't skip
fetching any heap tuples that are referenced by the index, because we
need to test them all with CheckForSerializableConflictOut(). The
old optimization that would ignore any references to blocks >=
rs_nblocks gets in the way of that requirement, because it means that
concurrent writes in that window are ignored.
Removing that optimization shouldn't affect correctness at any isolation
level, because any new tuples shouldn't be visible to an MVCC snapshot.
There also shouldn't be any error-causing references to heap blocks past
the end, because we should have held at least an AccessShareLock on the
table before the index scan. It can't get smaller while our transaction
is running. For now, though, we'll keep the optimization at lower
levels to avoid making unnecessary changes in a bug fix.
Back-patch to all supported releases. In release 11, the code is in a
different place but not fundamentally different. Fixes one aspect of
bug #17949.
Reported-by: Artem Anisimov <artem.anisimov.255@gmail.com>
Reviewed-by: Dmitry Dolgov <9erthalion6@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Discussion: https://postgr.es/m/17949-a0f17035294a55e2%40postgresql.org
When predicate-locking btrees, we have a special case for completely
empty btrees, since there is no page to lock. This was racy, because,
without buffer lock held, a matching key could be inserted between the
_bt_search() and the PredicateLockRelation() calls.
Fix, by rechecking _bt_search() after taking the relation-level SIREAD
lock, if using SERIALIZABLE isolation and an empty btree is discovered.
Back-patch to all supported releases. Fixes one aspect of bug #17949.
Reported-by: Artem Anisimov <artem.anisimov.255@gmail.com>
Reviewed-by: Dmitry Dolgov <9erthalion6@gmail.com>
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Discussion: https://postgr.es/m/17949-a0f17035294a55e2%40postgresql.org
When table_block_relation_estimate_size() estimated the number of tuples
in a relation without statistics (e.g. right after load), it did not
consider fillfactor when calculating density. With non-default
fillfactor values, this may result in significant overestimate of the
number of tuples - up to 10x with the minimum 10% fillfactor. This may
have unexpected consequences, e.g. when creating hash indexes.
This considers the current fillfactor value in the "no statistics" code
path. If the fillfactor changes after loading data into the table, the
estimate may be off. But that seems much less likely than changing the
fillfactor before the data load.
Reviewed-by: Corey Huinker, Peter Eisentraut
Discussion: https://postgr.es/m/cf154ef9-6bac-d268-b735-67a3443debba@enterprisedb.com
Tom Lane
Heikki Linnakangas
Amit Kapila
Nathan Bossart
Jeff Davis
Alexander Korotkov
Alvaro Herrera
Robert Haas
Michael Paquier
Peter Eisentraut
Bruce Momjian
Tomas Vondra
Masahiko Sawada
Peter Geoghegan
Thomas Munro
Andres Freund
David Rowley
Noah Misch
Etsuro Fujita
Daniel Gustafsson
Andrew Dunstan