The same code pattern is repeated 17 times for int64 counters (0 for
missing entry) and 5 times for timestamps (NULL for missing entry) on
table entries. This code is switched to use a macro for the basic code
instead, shaving a few hundred lines of originally-duplicated code. The
function names remain the same, but some fields of PgStat_StatTabEntry
have to be renamed to cope with the new style.
Author: Bertrand Drouvot
Reviewed-by: Nathan Bossart
Discussion: https:/postgr.es/m/20221204173207.GA2669116@nathanxps13
Passing a NULL snapshot (InvalidSnapshot) is going to work but only as long
as the index can't find any matching rows. This can be confusing for
the extension authors, so add an explicit check for this argument. The check
is implemented with Assert() in order to avoid overhead in release builds.
Reported-by: Sven Klemm
Discussion: https://postgr.es/m/CAJ7c6TPxitD4vbKyP-mpmC1XwyHdPPqvjLzm%2BVpB88h8LGgneQ%40mail.gmail.com
Author: Aleksander Alekseev
Reviewed-by: Pavel Borisov
The error messages reported during any failures while reading or
validating the header of a WAL currently includes only the offset of the
page but not the compiled LSN referring to the page, requiring an extra
step to compile it if looking at the surroundings with pg_waldump or
similar. Adding this information costs a bit in translation, but also
eases debugging.
Author: Bharath Rupireddy
Reviewed-by: Álvaro Herrera, Kyotaro Horiguchi, Maxim Orlov, Michael
Paquier
Discussion: https://postgr.es/m/CALj2ACWV=FCddsxcGbVOA=cvPyMr75YCFbSQT6g4KDj=gcJK4g@mail.gmail.com
ri_RootToPartitionMap is currently only initialized for tuple routing
target partitions, though a future commit will need the ability to use
it even for the non-partition child tables, so make adjustments to the
decouple it from the partitioning code.
Also, make it lazily initialized via ExecGetRootToChildMap(), making
that function its preferred access path. Existing third-party code
accessing it directly should no longer do so; consequently, it's been
renamed to ri_RootToChildMap, which also makes it consistent with
ri_ChildToRootMap.
ExecGetRootToChildMap() houses the logic of setting the map appropriately
depending on whether a given child relation is partition or not.
To support this, also add a separate entry point for TupleConversionMap
creation that receives an AttrMap. No new code here, just split an
existing function in two.
Author: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/CA+HiwqEYUhDXSK5BTvG_xk=eaAEJCD4GS3C6uH7ybBvv+Z_Tmg@mail.gmail.com
Previously, we'd compress only when the active range of array entries
reached Max(4 * PROCARRAY_MAXPROCS, 2 * pArray->numKnownAssignedXids).
If max_connections is large, the first term could result in not
compressing for a long time, resulting in much wastage of cycles in
hot-standby backends scanning the array to take snapshots. Get rid
of that term, and just bound it to 2 * pArray->numKnownAssignedXids.
That however creates the opposite risk, that we might spend too much
effort compressing. Hence, consider compressing only once every 128
commit records. (This frequency was chosen by benchmarking. While
we only tried one benchmark scenario, the results seem stable over
a fairly wide range of frequencies.)
Also, force compression when processing RecoveryInfo WAL records
(which should be infrequent); the old code could perform compression
then, but would do so only after the same array-range check as for
the transaction-commit path.
Also, opportunistically run compression if the startup process is about
to wait for WAL, though not oftener than once a second. This should
prevent cases where we waste lots of time by leaving the array
not-compressed for long intervals due to low WAL traffic.
Lastly, add a simple check to keep us from uselessly compressing
when the array storage is already compact.
Back-patch, as the performance problem is worse in pre-v14 branches
than in HEAD.
Simon Riggs and Michail Nikolaev, with help from Tom Lane and
Andres Freund.
Discussion: https://postgr.es/m/CALdSSPgahNUD_=pB_j=1zSnDBaiOtqVfzo8Ejt5J_k7qZiU1Tw@mail.gmail.com
When it's given as true, return a 0 in the position of the missing
column rather than raising an error.
This is currently unused, but it allows us to reimplement column
permission checking in a subsequent commit. It seems worth breaking
into a separate commit because it affects unrelated code.
Author: Amit Langote <amitlangote09@gmail.com>
Discussion: https://postgr.es/m/CA+HiwqFfiai=qBxPDTjaio_ZcaqUKh+FC=prESrB8ogZgFNNNQ@mail.gmail.com
Previously, an idle startup (recovery) process would wake up every 5
seconds to have a chance to poll for promote_trigger_file, even if that
GUC was not configured. That promotion triggering mechanism was
effectively superseded by pg_ctl promote and pg_promote() a long time
ago. There probably aren't many users left and it's very easy to change
to the modern mechanisms, so we agreed to remove the feature.
This is part of a campaign to reduce wakeups on idle systems.
Author: Simon Riggs <simon.riggs@enterprisedb.com>
Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Ian Lawrence Barwick <barwick@gmail.com>
Discussion: https://postgr.es/m/CANbhV-FsjnzVOQGBpQ589%3DnWuL1Ex0Ykn74Nh1hEjp2usZSR5g%40mail.gmail.com
When building hash indexes using the spool method, tuples are added to the
index page in hashkey order. Because of this, we can safely skip
performing the binary search on the existing tuples on the page to find
the location to insert the tuple based on its hashkey value. For this
case, we can just always put the tuple at the end of the item array as the
tuples will always arrive in hashkey order.
Testing has shown that this can improve hash index build speeds by 5-15%
with a unique set of integer values.
Author: Simon Riggs
Reviewed-by: David Rowley
Tested-by: David Zhang, Tomas Vondra
Discussion: https://postgr.es/m/CANbhV-GBc5JoG0AneUGPZZW3o4OK5LjBGeKe_icpC3R1McrZWQ@mail.gmail.com
Pass VACUUM parameters (VacuumParams state) to vacuum_set_xid_limits()
directly, rather than passing most individual VacuumParams fields as
separate arguments.
Also make vacuum_set_xid_limits() output parameter symbol names match
those used by its vacuumlazy.c caller.
Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-Wz=TE7gW5DgSahDkf0UEZigFGAoHNNN6EvSrdzC=Kn+hrA@mail.gmail.com
We shouldn't ever need to rely on whether HEAP_XMAX_INVALID is set in
t_infomask when considering whether or not an xmax should be deemed
already frozen, since that status flag is just a hint. The only
acceptable representation for an "xmax_already_frozen" raw xmax field is
the transaction ID value zero (also known as InvalidTransactionId).
Adjust code that superficially appeared to rely on HEAP_XMAX_INVALID to
make the rule about xmax_already_frozen clear. Also avoid needlessly
rereading the tuple's raw xmax.
Oversight in bugfix commit d2599ecf. There is no evidence that this
ever led to incorrect behavior, so no backpatch. The worst consequence
of this bug was that VACUUM could hypothetically fail to notice and
report on certain kinds of corruption, which seems fairly benign.
Author: Peter Geoghegan <pg@bowt.ie>
Discussion: https://postgr.es/m/CAH2-Wzkh3DMCDRPfhZxj9xCq9v3WmzvmbiCpf1dNKUBPadhCbQ@mail.gmail.com
Until now LWLockDequeueSelf() sequentially searched the list of waiters to see
if the current proc is still is on the list of waiters, or has already been
removed. In extreme workloads, where the wait lists are very long, this leads
to a quadratic behavior. #backends iterating over a list #backends
long. Additionally, the likelihood of needing to call LWLockDequeueSelf() in
the first place also increases with the increased length of the wait queue, as
it becomes more likely that a lock is released while waiting for the wait list
lock, which is held for longer during lock release.
Due to the exponential back-off in perform_spin_delay() this is surprisingly
hard to detect. We should make that easier, e.g. by adding a wait event around
the pg_usleep() - but that's a separate patch.
The fix is simple - track whether a proc is currently waiting in the wait list
or already removed but waiting to be woken up in PGPROC->lwWaiting.
In some workloads with a lot of clients contending for a small number of
lwlocks (e.g. WALWriteLock), the fix can substantially increase throughput.
As the quadratic behavior arguably is a bug, we might want to decide to
backpatch this fix in the future.
Author: Andres Freund <andres@anarazel.de>
Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Discussion: https://postgr.es/m/20221027165914.2hofzp4cvutj6gin@awork3.anarazel.de
Discussion: https://postgr.es/m/CALj2ACXktNbG=K8Xi7PSqbofTZozavhaxjatVc14iYaLu4Maag@mail.gmail.com
Standardize on the name snapshotConflictHorizon for all XID fields from
WAL records that generate recovery conflicts when in hot standby mode.
This supersedes the previous latestRemovedXid naming convention.
The new naming convention places emphasis on how the values are actually
used by REDO routines. How the values are generated during original
execution (details of which vary by record type) is deemphasized. Users
of tools like pg_waldump can now grep for snapshotConflictHorizon to see
all potential sources of recovery conflicts in a standardized way,
without necessarily having to consider which specific record types might
be involved.
Also bring a couple of WAL record types that didn't follow any kind of
naming convention into line. These are heapam's VISIBLE record type and
SP-GiST's VACUUM_REDIRECT record type. Now every WAL record whose REDO
routine calls ResolveRecoveryConflictWithSnapshot() passes through the
snapshotConflictHorizon field from its WAL record. This is follow-up
work to the refactoring from commit 9e540599 that made FREEZE_PAGE WAL
records use a standard snapshotConflictHorizon style XID cutoff.
No bump in XLOG_PAGE_MAGIC, since the underlying format of affected WAL
records doesn't change.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CAH2-Wzm2CQUmViUq7Opgk=McVREHSOorYaAjR1ZpLYkRN7_dPw@mail.gmail.com
Make heapam WAL records that describe freezing performed by VACUUM more
space efficient by storing each distinct "freeze plan" once, alongside
an array of associated page offset numbers (one per freeze plan). The
freeze plans required for most heap pages tend to naturally have a great
deal of redundancy, so this technique is very effective in practice. It
often leads to freeze WAL records that are less than 20% of the size of
equivalent WAL records generated using the previous approach.
The freeze plan concept was introduced by commit 3b97e6823b, which fixed
bugs in VACUUM's handling of MultiXacts. We retain the concept of
freeze plans, but go back to using page offset number arrays. There is
no loss of generality here because deduplication is an additive process
that gets applied mechanically when FREEZE_PAGE WAL records are built.
More than anything else, freeze plan deduplication is an optimization
that reduces the marginal cost of freezing additional tuples on pages
that will need to have at least one or two tuples frozen in any case.
Ongoing work that adds page-level freezing to VACUUM will take full
advantage of the improved cost profile through batching.
Also refactor some of the details surrounding recovery conflicts needed
to REDO freeze records in passing: make original execution responsible
for generating a standard latestRemovedXid cutoff, rather than working
backwards to get the same cutoff in the REDO routine. Bugfix commit
66fbcb0d2e did it the other way around, which is equivalent but obscures
what's going on.
Also rename the cutoff field from the WAL record/struct (rename the
field cutoff_xid to latestRemovedXid to match similar WAL records).
Processing of conflicts by REDO routines is already completely uniform,
so tools like pg_waldump should present the information driving the
process uniformly. There are two remaining WAL record types that still
don't quite follow this convention (heapam's VISIBLE record type and
SP-GiST's VACUUM_REDIRECT record type). They can be brought into line
by later work that totally standardizes how the cutoffs are presented.
Bump XLOG_PAGE_MAGIC.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: Masahiko Sawada <sawada.mshk@gmail.com>
Reviewed-By: Nathan Bossart <nathandbossart@gmail.com>
Reviewed-By: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://postgr.es/m/CAH2-Wz=XytErMnb8FAyFd+OQEbiipB0Q2FmFdXrggPL4VBnRYQ@mail.gmail.com
During XLOG_HASH_SPLIT_ALLOCATE_PAGE replay, we were checking for a
cleanup lock on the new bucket page after acquiring an exclusive lock on
it and raising a PANIC error on failure. However, it is quite possible
that checkpointer can acquire the pin on the same page before acquiring a
lock on it, and then the replay will lead to an error. So instead, directly
acquire the cleanup lock on the new bucket page during
XLOG_HASH_SPLIT_ALLOCATE_PAGE replay operation.
Reported-by: Andres Freund
Author: Robert Haas
Reviewed-By: Amit Kapila, Andres Freund, Vignesh C
Backpatch-through: 11
Discussion: https://postgr.es/m/20220810022617.fvjkjiauaykwrbse@awork3.anarazel.de
Instead of dozens of mostly-duplicate pg_foo_aclcheck() functions,
write one common function object_aclcheck() that can handle almost all
of them. We already have all the information we need, such as which
system catalog corresponds to which catalog table and which column is
the ACL column.
There are a few pg_foo_aclcheck() that don't work via the generic
function and have special APIs, so those stay as is.
I also changed most pg_foo_aclmask() functions to static functions,
since they are not used outside of aclchk.c.
Reviewed-by: Corey Huinker <corey.huinker@gmail.com>
Reviewed-by: Antonin Houska <ah@cybertec.at>
Discussion: https://www.postgresql.org/message-id/flat/95c30f96-4060-2f48-98b5-a4392d3b6066@enterprisedb.com
Instead of dozens of mostly-duplicate pg_foo_ownercheck() functions,
write one common function object_ownercheck() that can handle almost
all of them. We already have all the information we need, such as
which system catalog corresponds to which catalog table and which
column is the owner column.
Reviewed-by: Corey Huinker <corey.huinker@gmail.com>
Reviewed-by: Antonin Houska <ah@cybertec.at>
Discussion: https://www.postgresql.org/message-id/flat/95c30f96-4060-2f48-98b5-a4392d3b6066@enterprisedb.com
The original report was concerned with a possible inconsistency
between the heap and the visibility map, which I was unable to
confirm. The concern has been retracted.
However, there did seem to be a torn page hazard when using
checksums. By not setting the heap page LSN during redo, the
protections of minRecoveryPoint were bypassed. Fixed, along with a
misleading comment.
It may have been impossible to hit this problem in practice, because
it would require a page tear between the checksum and the flags, so I
am marking this as a theoretical risk. But, as discussed, it did
violate expectations about the page LSN, so it may have other
consequences.
Backpatch to all supported versions.
Reported-by: Konstantin Knizhnik
Reviewed-by: Konstantin Knizhnik
Discussion: https://postgr.es/m/fed17dac-8cb8-4f5b-d462-1bb4908c029e@garret.ru
Backpatch-through: 11
Previously, trying to set storage parameters on a partitioned table
always led to "unrecognized parameter foo", because the code expected
there might be some valid parameters; but there aren't any. The docs
make clear that it's intended that there never will be any, so let's
replace this useless search with a more to-the-point message.
Simon Riggs and Karina Litskevich
Discussion: https://postgr.es/m/CANbhV-H=eZ9kTR9mUgKGK0Qv9uXP=U+dQg3rinQHfTdFMhBA2A@mail.gmail.com
Add a little to the header comments for these functions to make it
clearer what guarantees about commit behavior are provided to callers.
(See commit f92944137 for context.)
Although this is only a comment change, it's really documentation
aimed at authors of extensions, so it seems appropriate to back-patch.
Yugo Nagata and Tom Lane, per further discussion of bug #17434.
Discussion: https://postgr.es/m/17434-d9f7a064ce2a88a3@postgresql.org
This routine is designed to write zeros to a file using vectored I/O,
for a size given by its caller, being useful when it comes to
initializing a file with a final size already known.
XLogFileInitInternal() in xlog.c is changed to use this new routine when
initializing WAL segments with zeros (wal_init_zero enabled). Note that
the aligned buffers used for the vectored I/O writes have a size of
XLOG_BLCKSZ, and not BLCKSZ anymore, as pg_pwrite_zeros() relies on
PGAlignedBlock while xlog.c originally used PGAlignedXLogBlock.
This routine will be used in a follow-up patch to do the pre-padding of
WAL segments for pg_receivewal and pg_basebackup when these are not
compressed.
Author: Bharath Rupireddy
Reviewed-by: Nathan Bossart, Andres Freund, Thomas Munro, Michael
Paquier
Discussion: https://www.postgresql.org/message-id/CALj2ACUq7nAb7%3DbJNbK3yYmp-SZhJcXFR_pLk8un6XgDzDF3OA%40mail.gmail.com
Previously, the description of XLOG_RUNNING_XACTS showed only
top-transaction XIDs and whether subtransactions overflowed. This commit
improves it to show individual subtransaction XIDs. This also improves the
description of overflowed subtransactions.
This additional information can be helpful for testing and debugging
purposes.
Author: Masahiko Sawada
Reviewd by: Fujii Masao, Kyotaro Horiguchi, Ashutosh Bapat, Bharath Rupireddy
Discussion: https://postgr.es/m/CAD21AoAqvaE+XEeXHHPdAGQPcCoGXxuoeutq_nWhUSQvTt5+tA@mail.gmail.com
We have various requirements when using a dlist_head to keep track of the
number of items in the list. This, traditionally, has been done by
maintaining a counter variable in the calling code. Here we tidy this up
by adding "dclist", which is very similar to dlist but also keeps track of
the number of items stored in the list.
Callers may use the new dclist_count() function when they need to know how
many items are stored. Obtaining the count is an O(1) operation.
For simplicity reasons, dclist and dlist both use dlist_node as their node
type and dlist_iter/dlist_mutable_iter as their iterator type. dclists
have all of the same functionality as dlists except there is no function
named dclist_delete(). To remove an item from a list dclist_delete_from()
must be used. This requires knowing which dclist the given item is stored
in.
Additionally, here we also convert some dlists where additional code
exists to keep track of the number of items stored and to make these use
dclists instead.
Author: David Rowley
Reviewed-by: Bharath Rupireddy, Aleksander Alekseev
Discussion: https://postgr.es/m/CAApHDvrtVxr+FXEX0VbViCFKDGxA3tWDgw9oFewNXCJMmwLjLg@mail.gmail.com
This is similar to 7d25958, and this commit takes care of all the
remaining inconsistencies between the initial value used in the C
variable associated to a GUC and its default value stored in the GUC
tables (as of pg_settings.boot_val).
Some of the initial values of the GUCs updated rely on a compile-time
default. These are refactored so as the GUC table and its C declaration
use the same values. This makes everything consistent with other
places, backend_flush_after, bgwriter_flush_after, port,
checkpoint_flush_after doing so already, for example.
Extracted from a larger patch by Peter Smith. The spots updated in the
modules are from me.
Author: Peter Smith, Michael Paquier
Reviewed-by: Nathan Bossart, Tom Lane, Justin Pryzby
Discussion: https://postgr.es/m/CAHut+PtHE0XSfjjRQ6D4v7+dqzCw=d+1a64ujra4EX8aoc_Z+w@mail.gmail.com
Here we add a new 'copy' parameter to tuplesort_getdatum so that we can
instruct the function not to datumCopy() byref Datums before returning.
Similar to 91e9e89dc, this can provide significant performance
improvements in nodeSort when sorting by a single byref column and the
sort's targetlist contains only that column.
This allows us to re-enable Datum sorts for byref types which was disabled
in 3a5817695 due to a reported memory leak.
Additionally, here we slightly optimize DISTINCT aggregates so that we no
longer perform any datumCopy() when we find the current value not to be
distinct from the previous value. Previously the code would always take a
copy of the most recent Datum and pfree the previous value, even when the
values were the same. Testing shows a small but noticeable performance
increase when aggregate transitions are skipped due to the current
transition value being the same as the prior one.
Author: David Rowley
Discussion: https://postgr.es/m/CAApHDvqS6wC5U==k9Hd26E4EQXH3QR67-T4=Q1rQ36NGvjfVSg@mail.gmail.com
Discussion: https://postgr.es/m/CAApHDvqHonfe9G1cVaKeHbDx70R_zCrM3qP2AGXpGrieSKGnhA@mail.gmail.com
Commit df3737a651 added an incorrect assertion about the preconditions
for invoking the backup cleanup callback: it misfires at session end in
case a backup completes successfully. Fix it, using coding from Michaël
Paquier. Also add some tests for the various cases.
Reported by Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Discussion: https://postgr.es/m/20221021.161038.1277961198945653224.horikyota.ntt@gmail.com
Since pg_backup_start() and pg_backup_stop() exist, the tablespace map
data and the backup state data (backup_label string until 7d70809) have
been allocated in the TopMemoryContext. This approach would cause
memory leaks in the session calling these functions if failures happen
before pg_backup_stop() ends, leaking more memory on repeated failures.
Both things need little memory so that would not be really noticeable
for most users, except perhaps connection poolers with long-lived
connections able to trigger backup failures with these functions.
This commit improves the logic in this area by not allocating anymore
the backup-related data that needs to travel across the SQL-callable
backup functions in TopMemoryContext, by using instead a dedicated
memory context child of TopMemoryContext. The memory context is created
in pg_backup_start() and deleted when finishing pg_backup_stop(). In
the event of an in-flight failure, this memory context gets reset in the
follow-up pg_backup_start() call, so as we are sure that only one run
worth of data is leaked at any time. Some cleanup was already done for
the backup data on a follow-up call of pg_backup_start(), but using a
memory context makes the whole simpler.
BASE_BACKUP commands are executed in isolation, relying on the memory
context created for replication commands, hence these do not need such
an extra logic.
Author: Bharath Rupireddy
Reviewed-by: Robert Haas, Alvaro Herrera, Cary Huang, Michael Paquier
Discussion: https://postgr.es/m/CALj2ACXqvfKF2B0beQ=aJMdWnpNohmBPsRg=EDQj_6y1t2O8mQ@mail.gmail.com
After commit 39969e2a1e, ->forcePageWrites is no longer very
interesting: we can just test whether runningBackups is different from 0.
This simplifies some code, so do away with it.
Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Discussion: https://postgr.es/m/39969e2a1e4d7f5a37f3ef37d53bbfe171e7d77a
We had two copies of almost identical logic to revert shared memory
state when a running backup aborts; we can remove
pg_backup_start_callback if we adapt do_pg_abort_backup so that it can
be used for this purpose too.
However, in order for this to work, we have to repurpose the flag passed
to do_pg_abort_backup. It used to indicate whether to throw a warning
(and the only caller always passed true). It now indicates whether the
callback is being called at start time (in which case the session backup
state is known not to have been set to RUNNING yet, so action is always
taken) or shmem time (in which case action is only taken if the session
backup state is RUNNING). Thus the meaning of the flag is no longer
superfluous, but it's actually quite critical to get right. I (Álvaro)
chose to change the polarity and the code flow re. the flag from what
Bharath submitted, for coding clarity.
Co-authored-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Discussion: https://www.postgresql.org/message-id/20221013111330.564fk5tkwe3ha77l%40alvherre.pgsql
Per discussion, the existing routine name able to initialize a SRF
function with materialize mode is unpopular, so rename it. Equally, the
flags of this function are renamed, as of:
- SRF_SINGLE_USE_EXPECTED -> MAT_SRF_USE_EXPECTED_DESC
- SRF_SINGLE_BLESS -> MAT_SRF_BLESS
The previous function and flags introduced in 9e98583 are kept around
for compatibility purposes, so as any extension code already compiled
with v15 continues to work as-is. The declarations introduced here for
compatibility will be removed from HEAD in a follow-up commit.
The new names have been suggested by Andres Freund and Melanie
Plageman.
Discussion: https://postgr.es/m/20221013194820.ciktb2sbbpw7cljm@awork3.anarazel.de
Backpatch-through: 15
Previously GetCurrentTransactionStopTimestamp() computed a new timestamp
whenever xactStopTimestamp was unset and xactStopTimestamp was only set when a
commit or abort record was written.
An upcoming patch will add additional calls to
GetCurrentTransactionStopTimestamp() from pgstats. To avoid computing
timestamps multiple times, set xactStopTimestamp in
GetCurrentTransactionStopTimestamp() if not already set.
Author: Dave Page <dpage@pgadmin.org>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Vik Fearing <vik@postgresfriends.org>
Discussion: https://postgr.es/m/20220906155325.an3xesq5o3fq36gt%40awork3.anarazel.de
Contrary to what is documented in src/backend/access/transam/README,
ginHeapTupleFastInsert() had a few ordering issues with the way it does
its WAL operations when inserting items in its fast path.
First, when using a separate list, XLogBeginInsert() was being always
called before START_CRIT_SECTION(), and in this case a second thing was
wrong when merging lists, as an exclusive lock was taken on the tail
page *before* calling XLogBeginInsert(). Finally, when inserting items
into a tail page, the order of XLogBeginInsert() and
START_CRIT_SECTION() was reversed. This commit addresses all these
issues by moving the calls of XLogBeginInsert() after all the pages
logged are locked and pinned, within a critical section.
Author: Matthias van de Meent, Zhang Mingli
Discussion: https://postgr.es/m/CAEze2WhL8uLMqynnnCu1LAPwxD5RKEo0nHV+eXGg_N6ELU88HQ@mail.gmail.com
An LSN was calculated from a segment number, a segment size and a
position offset, matching exactly the LSN given by the caller of
XLogReaderValidatePageHeader(). This change removes the extra LSN
calculation, relying only on the LSN given by the function caller
instead.
Author: Bharath Rupireddy
Reviewed-by: Richard Guo, Álvaro Herrera, Kyotaro Horiguchi
Discussion: https://postgr.es/m/CALj2ACXuh4Ms9j9sxMYdtHEe=5sFcyrs-GAHyADu_A_G71kZTg@mail.gmail.com