After commits 85f6b49c2c and 3ba59ccc89, we can allow parallel inserts
which was earlier not possible as parallel group members won't conflict
for relation extension and page lock. In those commits, we forgot to
update comments at few places.
Author: Amit Kapila
Reviewed-by: Robert Haas and Dilip Kumar
Backpatch-through: 13
Discussion: https://postgr.es/m/CAFiTN-tMrQh5FFMPx5aWJ+1gi1H6JxktEhq5mDwCHgnEO5oBkA@mail.gmail.com
This feature has been a thorn in our sides for a long time, causing
many grammatical ambiguity problems. It doesn't seem worth the
pain to continue to support it, so remove it.
There are some follow-on improvements we can make in the grammar,
but this commit only removes the bare minimum number of productions,
plus assorted backend support code.
Note that pg_dump and psql continue to have full support, since
they may be used against older servers. However, pg_dump warns
about postfix operators. There is also a check in pg_upgrade.
Documentation-wise, I (tgl) largely removed the "left unary"
terminology in favor of saying "prefix operator", which is
a more standard and IMO less confusing term.
I included a catversion bump, although no initial catalog data
changes here, to mark the boundary at which oprkind = 'r'
stopped being valid in pg_operator.
Mark Dilger, based on work by myself and Robert Haas;
review by John Naylor
Discussion: https://postgr.es/m/38ca86db-42ab-9b48-2902-337a0d6b8311@2ndquadrant.com
For parallel btree scan to work for array of scan keys, it should reach
BTPARALLEL_DONE state once for every distinct combination of array keys.
This is required to ensure that the parallel workers don't try to seize
blocks at the same time for different scan keys. We missed to update this
state when we discovered that the scan keys can't be satisfied.
Author: James Hunter
Reviewed-by: Amit Kapila
Tested-by: Justin Pryzby
Backpatch-through: 10, where it was introduced
Discussion: https://postgr.es/m/4248CABC-25E3-4809-B4D0-128E1BAABC3C@amazon.com
In the particular case of GRANTED BY, this is specified in the SQL
standard. Since in PostgreSQL, CURRENT_ROLE is equivalent to
CURRENT_USER, and CURRENT_USER is already supported here, adding
CURRENT_ROLE is trivial. The other cases are PostgreSQL extensions,
but for the same reason it also makes sense there.
Reviewed-by: Vik Fearing <vik@postgresfriends.org>
Reviewed-by: Asif Rehman <asifr.rehman@gmail.com>
Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
Discussion: https://www.postgresql.org/message-id/flat/f2feac44-b4c5-f38f-3699-2851d6a76dc9%402ndquadrant.com
This adds a new optional support function to the GiST access method:
sortsupport. If it is defined, the GiST index is built by sorting all data
to the order defined by the sortsupport's comparator function, and packing
the tuples in that order to GiST pages. This is similar to how B-tree
index build works, and is much faster than inserting the tuples one by
one. The resulting index is smaller too, because the pages are packed more
tightly, upto 'fillfactor'. The normal build method works by splitting
pages, which tends to lead to more wasted space.
The quality of the resulting index depends on how good the opclass-defined
sort order is. A good order preserves locality of the input data.
As the first user of this facility, add 'sortsupport' function to the
point_ops opclass. It sorts the points in Z-order (aka Morton Code), by
interleaving the bits of the X and Y coordinates.
Author: Andrey Borodin
Reviewed-by: Pavel Borisov, Thomas Munro
Discussion: https://www.postgresql.org/message-id/1A36620E-CAD8-4267-9067-FB31385E7C0D%40yandex-team.ru
Because the code path taken for SQL commands executed in a walsender
will update the process title, we pretty much have to update the
title for replication commands as well. Otherwise, the title shows
"idle" for the rest of a logical walsender's lifetime once it's
executed any SQL command.
Playing with this, I confirm that a walsender now typically spends
most of its life reporting
walsender postgres [local] START_REPLICATION
Considering this in isolation, it might be better to have it say
walsender postgres [local] sending replication data
However, consistency with the other cases seems to be a stronger
argument.
In passing, remove duplicative pgstat_report_activity call.
Discussion: https://postgr.es/m/880181.1600026471@sss.pgh.pa.us
Since commit fd5942c18f (2012, 9.3-era), walsender has been sending
completion tags for certain replication commands twice -- and they're
not even consistent. Apparently neither libpq nor JDBC have a problem
with it, but it's not kosher. Fix by remove the EndCommand() call in
the common code path for them all, and inserting specific calls to
EndReplicationCommand() specifically in those places where it's needed.
EndReplicationCommand() is a new simple function to send the completion
tag for replication commands. Do this instead of sending a generic
SELECT completion tag for them all, which was also pretty bogus (if
innocuous). While at it, change StartReplication() to use
EndReplicationCommand() instead of pg_puttextmessage().
In commit 2f9661311b, I failed to realize that replication commands
are not close-enough kin of regular SQL commands, so the
DROP_REPLICATION_SLOT tag I added is undeserved and a type pun. Take it
out.
Backpatch to 13, where the latter commit appeared. The duplicate tag
has been sent since 9.3, but since nothing is broken, it doesn't seem
worth fixing.
Per complaints from Tom Lane.
Discussion: https://postgr.es/m/1347966.1600195735@sss.pgh.pa.us
We decided that the policy established in commit 7634bd4f6 for
the bgwriter, checkpointer, walwriter, and walreceiver processes,
namely that they should accept SIGQUIT at all times, really ought
to apply uniformly to all postmaster children. Therefore, get
rid of the duplicative and inconsistent per-process code for
establishing that signal handler and removing SIGQUIT from BlockSig.
Instead, make InitPostmasterChild do it.
The handler set up by InitPostmasterChild is SignalHandlerForCrashExit,
which just summarily does _exit(2). In interactive backends, we
almost immediately replace that with quickdie, since we would prefer
to try to tell the client that we're dying. However, this patch is
changing the behavior of autovacuum (both launcher and workers), as
well as walsenders. Those processes formerly also used quickdie,
but AFAICS that was just mindless copy-and-paste: they don't have
any interactive client that's likely to benefit from being told this.
The stats collector continues to be an outlier, in that it thinks
SIGQUIT means normal exit. That should probably be changed for
consistency, but there's another patch set where that's being
dealt with, so I didn't do so here.
Discussion: https://postgr.es/m/644875.1599933441@sss.pgh.pa.us
Since there is only one place that actually needs the partition check
expression, namely ExecPartitionCheck, it's better to fetch it from
the relcache there. In this way we will never fetch it at all if
the query never has use for it, and we still fetch it just once when
we do need it.
The reason for taking an interest in this is that if the relcache
doesn't already have the check expression cached, fetching it
requires obtaining AccessShareLock on the partition root. That
means that operations that look like they should only touch the
partition itself will also take a lock on the root. In particular
we observed that TRUNCATE on a partition may take a lock on the
partition's root, contributing to a deadlock situation in parallel
pg_restore.
As written, this patch does have a small cost, which is that we
are microscopically reducing efficiency for the case where a partition
has an empty check expression. ExecPartitionCheck will be called,
and will go through the motions of setting up and checking an empty
qual, where before it would not have been called at all. We could
avoid that by adding a separate boolean flag to track whether there
is a partition expression to test. However, this case only arises
for a default partition with no siblings, which surely is not an
interesting case in practice. Hence adding complexity for it
does not seem like a good trade-off.
Amit Langote, per a suggestion by me
Discussion: https://postgr.es/m/VI1PR03MB31670CA1BD9625C3A8C5DD05EB230@VI1PR03MB3167.eurprd03.prod.outlook.com
If a partitioned table's column is already marked NOT NULL, there is
no need to examine its partitions, because we can rely on previous
DDL to have enforced that the child columns are NOT NULL as well.
(Unfortunately, the same cannot be said for traditional inheritance,
so for now we have to restrict the optimization to partitioned tables.)
Hence, we may skip recursing to child tables in this situation.
The reason this case is worth worrying about is that when pg_dump dumps
a partitioned table having a primary key, it will include the requisite
NOT NULL markings in the CREATE TABLE commands, and then add the
primary key as a separate step. The primary key addition generates a
SET NOT NULL as a subcommand, just to be sure. So the situation where
a SET NOT NULL is redundant does arise in the real world.
Skipping the recursion does more than just save a few cycles: it means
that a command such as "ALTER TABLE ONLY partition_parent ADD PRIMARY
KEY" will take locks only on the partition parent table, not on the
partitions. It turns out that parallel pg_restore is effectively
assuming that that's true, and has little choice but to do so because
the dependencies listed for such a TOC entry don't include the
partitions. pg_restore could thus issue this ALTER while data restores
on the partitions are still in progress. Taking unnecessary locks on
the partitions not only hurts concurrency, but can lead to actual
deadlock failures, as reported by Domagoj Smoljanovic.
(A contributing factor in the deadlock is that TRUNCATE on a child
partition wants a non-exclusive lock on the parent. This seems
likewise unnecessary, but the fix for it is more invasive so we
won't consider back-patching it. Fortunately, getting rid of one
of these two poor behaviors is enough to remove the deadlock.)
Although support for partitioned primary keys came in with v11,
this patch is dependent on the SET NOT NULL refactoring done by
commit f4a3fdfbd, so we can only patch back to v12.
Patch by me; thanks to Alvaro Herrera and Amit Langote for review.
Discussion: https://postgr.es/m/VI1PR03MB31670CA1BD9625C3A8C5DD05EB230@VI1PR03MB3167.eurprd03.prod.outlook.com
The code recorded cache invalidation events by zeroing the "localreloid"
field of affected cache entries. However, it's possible for an inval
event to occur even while we have the entry open and locked. So an
ill-timed inval could result in "cache lookup failed for relation 0"
errors, if the worker's code tried to use the cleared field. We can
fix that by creating a separate bool field to record whether the entry
needs to be revalidated. (In the back branches, cram the bool into
what had been padding space, to avoid an ABI break in the somewhat
unlikely event that any extension is looking at this struct.)
Also, rearrange the logic in logicalrep_rel_open so that it
does the right thing in cases where table_open would fail.
We should retry the lookup by name in that case, but we didn't.
The real-world impact of this is probably small. In the first place,
the error conditions are very low probability, and in the second place,
the worker would just exit and get restarted. We only noticed because
in a CLOBBER_CACHE_ALWAYS build, the failure can occur repeatedly,
preventing the worker from making progress. Nonetheless, it's clearly
a bug, and it impedes a useful type of testing; so back-patch to v10
where this code was introduced.
Discussion: https://postgr.es/m/1032727.1600096803@sss.pgh.pa.us
Previously, it was based on nBlocksAllocated to account for tapes with
open write buffers that may not have made it to the BufFile yet.
That was unnecessary, because callers do not need to get the number of
blocks while a tape has an open write buffer; and it also conflicted
with the preallocation logic added for HashAgg.
Reviewed-by: Peter Geoghegan
Discussion: https://postgr.es/m/ce5af05900fdbd0e9185747825a7423c48501964.camel@j-davis.com
Backpatch-through: 13
In commit 464824323e, for each RelationSyncEntry we maintained the list
of xids (streamed_txns) for which we have already sent the schema. This
helps us to track when to send the schema to the downstream node for
replication of streaming transactions. Before this list got initialized,
we were processing invalidation messages which access this list and led
to an assertion failure.
In passing, clean up the nearby code:
* Initialize the list of xids with NIL instead of NULL which is our usual
coding practice.
* Remove the MemoryContext switch for creating a RelationSyncEntry in dynahash.
Diagnosed-by: Amit Kapila and Tom Lane
Author: Amit Kapila
Reviewed-by: Tom Lane and Dilip Kumar
Discussion: https://postgr.es/m/904373.1600033123@sss.pgh.pa.us
This function could often be seen in profiles of vacuum and could often
be a significant bottleneck during recovery. The problem was that a qsort
was performed in order to sort an array of item pointers in reverse offset
order so that we could use that to safely move tuples up to the end of the
page without overwriting the memory of yet-to-be-moved tuples. i.e. we
used to compact the page starting at the back of the page and move towards
the front. The qsort that this required could be expensive for pages with
a large number of tuples.
In this commit, we take another approach to tuple compactification.
Now, instead of sorting the remaining item pointers array we first check
if the array is presorted and only memmove() the tuples that need to be
moved. This presorted check can be done very cheaply in the calling
functions when the array is being populated. This presorted case is very
fast.
When the item pointer array is not presorted we must copy tuples that need
to be moved into a temp buffer before copying them back into the page
again. This differs from what we used to do here as we're now copying the
tuples back into the page in reverse line pointer order. Previously we
left the existing order alone. Reordering the tuples results in an
increased likelihood of hitting the pre-sorted case the next time around.
Any newly added tuple which consumes a new line pointer will also maintain
the correct sort order of tuples in the page which will also result in the
presorted case being hit the next time. Only consuming an unused line
pointer can cause the order of tuples to go out again, but that will be
corrected next time the function is called for the page.
Benchmarks have shown that the non-presorted case is at least equally as
fast as the original qsort method even when the page just has a few
tuples. As the number of tuples becomes larger the new method maintains
its performance whereas the original qsort method became much slower when
the number of tuples on the page became large.
Author: David Rowley
Reviewed-by: Thomas Munro
Tested-by: Jakub Wartak
Discussion: https://postgr.es/m/CA+hUKGKMQFVpjr106gRhwk6R-nXv0qOcTreZuQzxgpHESAL6dw@mail.gmail.com
ALTER TABLE commands in an extension script are added to an event
trigger command list; but starting with commit b5810de3f4 they do so in
a memory context that's too short-lived, so when execution ends and time
comes to use the entries, they've already been freed.
(This would also be a problem with ALTER TABLE commands in a
multi-command query string, but these serendipitously end in
PortalContext -- which probably explains why it took so long for this to
be reported.)
Fix by using the memory context specifically set for that, instead.
Backpatch to 13, where the aforementioned commit appeared.
Reported-by: Philippe Beaudoin
Author: Jehan-Guillaume de Rorthais <jgdr@dalibo.com>
Discussion: https://postgr.es/m/20200902193715.6e0269d4@firost
Introduced in 0aa8f7640.
MSVC warned about performing 32-bit bit shifting when it appeared like we
might like a 64-bit result. We did, but it just so happened that none of
the calls to this function could have caused the 32-bit shift to overflow.
Here we just cast the constant to int64 to make the compiler happy.
Discussion: https://postgr.es/m/CAApHDvofA_vsrpC13mq_hZyuye5B-ssKEaer04OouXYCO5-uXQ@mail.gmail.com
A walsender process that has executed a SQL command left the text of
that command in pg_stat_activity.query indefinitely, which is quite
confusing if it's in RUNNING state but not doing that query. An easy
and useful fix is to treat replication commands as if they were SQL
queries, and show them in pg_stat_activity according to the same rules
as for regular queries. While we're at it, it seems also sensible to
set debug_query_string, allowing error logging and debugging to see
the replication command.
While here, clean up assorted silliness in exec_replication_command:
* The SQLCmd path failed to restore CurrentMemoryContext to the caller's
value, and failed to delete the temp context created in this routine.
It's only through great good fortune that these oversights did not
result in long-term memory leaks or other problems. It seems cleaner
to code SQLCmd as a separate early-exit path, so do it like that.
* Remove useless duplicate call of SnapBuildClearExportedSnapshot().
* replication_scanner_finish() was never called.
None of those things are significant enough to merit a backpatch,
so this is for HEAD only.
Discussion: https://postgr.es/m/880181.1600026471@sss.pgh.pa.us
3c84046 is the original commit that introduced index_set_state_flags(),
where the presence of SnapshotNow made necessary the use of an in-place
update. SnapshotNow has been removed in 813fb03, so there is no actual
reasons to not make this operation transactional.
Note that while making the operation more robust, using a transactional
operation in this routine was not strictly necessary as there was no use
case for it yet. However, some future features are going to need a
transactional behavior, like support for CREATE/DROP INDEX CONCURRENTLY
with partitioned tables, where indexes in a partition tree need to have
all their pg_index.indis* flags updated in the same transaction to make
the operation stable to the end-user by keeping partition trees
consistent, even with a failure mid-flight.
REINDEX CONCURRENTLY uses already transactional updates when swapping
the old and new indexes, making this change more consistent with the
index-swapping logic.
Author: Michael Paquier
Reviewed-by: Anastasia Lubennikova
Discussion: https://postgr.es/m/20200903080440.GA8559@paquier.xyz
transformCreateStmt() adjusts the transformed statement's RangeVar
to specify the target schema explicitly, for the express reason
of making sure that auxiliary statements derived by parse
transformation operate on the right table. But the refactoring
I did in commit 502898192 got this wrong and passed the untransformed
RangeVar to expandTableLikeClause(). This could lead to assertion
failures or weird misbehavior if the wrong table was accessed.
Per report from Alexander Lakhin. Like the previous patch, back-patch
to all supported branches.
Discussion: https://postgr.es/m/05051f9d-b32b-cb35-6735-0e9f2ab86b5f@gmail.com
We use the timestamp of the global statfile if we are not able to
determine it for a particular database in case the entry for that database
doesn't exist. However, we were using it even when the statfile is
corrupt.
As there is no user reported issue and it is not clear if there is any
impact of this on actual application so decided not to backpatch.
Reported-by: Amit Kapila
Author: Amit Kapila
Reviewed-by: Sawada Masahiko, Magnus Hagander and Alvaro Herrera
Discussion: https://postgr.es/m/CAA4eK1J3oTJKyVq6v7K4d3jD+vtnruG9fHRib6UuWWsrwAR6Aw@mail.gmail.com
The bgwriter, checkpointer, walwriter, and walreceiver processes
claimed to allow SIGQUIT "at all times". In reality SIGQUIT
would get re-blocked during error recovery, because we didn't
update the actual signal mask immediately, so sigsetjmp() would
save and reinstate a mask that includes SIGQUIT.
This appears to be simply a coding oversight. There's never a
good reason to hold off SIGQUIT in these processes, because it's
going to just call _exit(2) which should be safe enough, especially
since the postmaster is going to tear down shared memory afterwards.
Hence, stick in PG_SETMASK() calls to install the modified BlockSig
mask immediately.
Also try to improve the comments around sigsetjmp blocks. Most of
them were just referencing postgres.c, which is misleading because
actually postgres.c manages the signals differently.
No back-patch, since there's no evidence that this is causing any
problems in the field.
Discussion: https://postgr.es/m/CALDaNm1d1hHPZUg3xU4XjtWBOLCrA+-2cJcLpw-cePZ=GgDVfA@mail.gmail.com
Currently, no useful trace is left in the logs when the postmaster
is forced to use SIGKILL to shut down children that failed to respond
to SIGQUIT. Some questions were raised about how often that scenario
happens in the buildfarm, so let's add a LOG-level message showing
that it happened.
Discussion: https://postgr.es/m/1850884.1599601164@sss.pgh.pa.us
Although 58c6feccf fixed the case for SIGQUIT, we were still calling
proc_exit() from signal handlers for SIGTERM and timeout failures in
ProcessStartupPacket. Fortunately, at the point where that code runs,
we haven't yet connected to shared memory in any meaningful way, so
there is nothing we need to undo in shared memory. This means it
should be safe to use _exit(1) here, ie, not run any atexit handlers
but also inform the postmaster that it's not a crash exit.
To make sure nobody breaks the "nothing to undo" expectation, add
a cross-check that no on-shmem-exit or before-shmem-exit handlers
have been registered yet when we finish using these signal handlers.
This change is simple enough that maybe it could be back-patched,
but I won't risk that right now.
Discussion: https://postgr.es/m/1850884.1599601164@sss.pgh.pa.us
Bring the signal handling for startup-packet collection into line
with the policy established in commits bedadc732 and 8e19a8264,
namely don't risk running atexit callbacks when handling SIGQUIT.
Ideally, we'd not do so for SIGTERM or timeout interrupts either,
but that change seems a bit too risky for the back branches.
For now, just improve the comments in this area to describe the risk.
Also relocate where BackendInitialize re-disables these interrupts,
to minimize the code span where they're active. This doesn't buy
a whole lot of safety, but it can't hurt.
In passing, rename startup_die() to remove confusion about whether
it is for the startup process.
Like the previous commits, back-patch to all supported branches.
Discussion: https://postgr.es/m/1850884.1599601164@sss.pgh.pa.us
Move applicable code out of RelationBuildDesc(), which nailed relations
bypass. Non-assert builds experienced no known problems. Back-patch to
v13, where commit c6b92041d3 introduced
rd_firstRelfilenodeSubid.
Kyotaro Horiguchi. Reported by Justin Pryzby.
Discussion: https://postgr.es/m/20200907023737.GA7158@telsasoft.com
Commit 8e19a8264 changed the SIGQUIT handlers of almost all server
processes not to run atexit callbacks. The archiver process was
skipped, perhaps because it's not connected to shared memory; but
it's just as true here that running atexit callbacks in a signal
handler is unsafe. So let's make it work like the rest.
In HEAD and v13, we can use the common SignalHandlerForCrashExit
handler. Before that, just tweak pgarch_exit to use _exit(2)
explicitly.
Like the previous commit, back-patch to all supported branches.
Kyotaro Horiguchi, back-patching by me
Discussion: https://postgr.es/m/1850884.1599601164@sss.pgh.pa.us
Partitioning tuple route code assumes that the partition chosen while
descending the partition hierarchy is always the correct one. This is
true except when the partition is the default partition and another
partition has been added concurrently: the partition constraint changes
and we don't recheck it. This can lead to tuples mistakenly being added
to the default partition that should have been rejected.
Fix by rechecking the default partition constraint while descending the
hierarchy.
An isolation test based on the reproduction steps described by Hao Wu
(with tweaks for extra coverage) is included.
Backpatch to 12, where this bug came in with 898e5e3290.
Reported by: Hao Wu <hawu@vmware.com>
Author: Amit Langote <amitlangote09@gmail.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/CA+HiwqFqBmcSSap4sFnCBUEL_VfOMmEKaQ3gwUhyfa4c7J_-nA@mail.gmail.com
Discussion: https://postgr.es/m/DM5PR0501MB3910E97A9EDFB4C775CF3D75A42F0@DM5PR0501MB3910.namprd05.prod.outlook.com
Historically, cancel_before_shmem_exit() just silently did nothing
if the specified callback wasn't the top-of-stack. The folly of
ignoring this case was exposed by the bugs fixed in 303640199 and
bab150045, so let's make it throw elog(ERROR) instead.
There is a decent argument to be made that PG_ENSURE_ERROR_CLEANUP
should use some separate infrastructure, so it wouldn't break if
something inside the guarded code decides to register a new
before_shmem_exit callback. However, a survey of the surviving
uses of before_shmem_exit() and PG_ENSURE_ERROR_CLEANUP doesn't
show any plausible conflicts of that sort today, so for now we'll
forgo the extra complexity. (It will almost certainly become
necessary if anyone ever wants to wrap PG_ENSURE_ERROR_CLEANUP
around arbitrary user-defined actions, though.)
No backpatch, since this is developer support not a production issue.
Bharath Rupireddy, per advice from Andres Freund, Robert Haas, and myself
Discussion: https://postgr.es/m/CALj2ACWk7j4F2v2fxxYfrroOF=AdFNPr1WsV+AGtHAFQOqm_pw@mail.gmail.com
The problem is caused by me (Andres) having ProcSleep() look at the
wrong PGPROC entry in 5788e258bb.
Unfortunately it seems hard to write a reliable test for autovacuum
cancellations. Perhaps somebody will come up with a good approach, but
it seems worth fixing the issue even without a test.
Reported-By: Jeff Janes <jeff.janes@gmail.com>
Author: Jeff Janes <jeff.janes@gmail.com>
Discussion: https://postgr.es/m/CAMkU=1wH2aUy+wDRDz+5RZALdcUnEofV1t9PzXS_gBJO9vZZ0Q@mail.gmail.com
This essentially reverts a micro-optimization I made years ago,
as part of the much larger commit d72f6c750. It's doubtful
that there was any hard evidence for it being helpful even then,
and the case is even more dubious now that modern compilers
are so much smarter about inlining memset().
The proximate reason for undoing it is to get rid of the type punning
inherent in MemSet, for fear that that may cause problems now that
we're applying additional optimization switches to numeric.c.
At the very least this'll silence some warnings from a few old
buildfarm animals.
(It's probably past time for another look at whether MemSet is still
worth anything at all, but I do not propose to tackle that question
right now.)
Discussion: https://postgr.es/m/CAJ3gD9evtA_vBo+WMYMyT-u=keHX7-r8p2w7OSRfXf42LTwCZQ@mail.gmail.com
Until now, REINDEX was not able to work with partitioned tables and
indexes, forcing users to reindex partitions one by one. This extends
REINDEX INDEX and REINDEX TABLE so as they can accept a partitioned
index and table in input, respectively, to reindex all the partitions
assigned to them with physical storage (foreign tables, partitioned
tables and indexes are then discarded).
This shares some logic with schema and database REINDEX as each
partition gets processed in its own transaction after building a list of
relations to work on. This choice has the advantage to minimize the
number of invalid indexes to one partition with REINDEX CONCURRENTLY in
the event a cancellation or failure in-flight, as the only indexes
handled at once in a single REINDEX CONCURRENTLY loop are the ones from
the partition being working on.
Isolation tests are added to emulate some cases I bumped into while
developing this feature, particularly with the concurrent drop of a
leaf partition reindexed. However, this is rather limited as LOCK would
cause REINDEX to block in the first transaction building the list of
partitions.
Per its multi-transaction nature, this new flavor cannot run in a
transaction block, similarly to REINDEX SCHEMA, SYSTEM and DATABASE.
Author: Justin Pryzby, Michael Paquier
Reviewed-by: Anastasia Lubennikova
Discussion: https://postgr.es/m/db12e897-73ff-467e-94cb-4af03705435f.adger.lj@alibaba-inc.com
Tomas Vondra observed that the IO behavior for HashAgg tends to be
worse than for Sort. Penalize HashAgg IO costs accordingly.
Also, account for the CPU effort of spilling the tuples and reading
them back.
Discussion: https://postgr.es/m/20200906212112.nzoy5ytrzjjodpfh@development
Reviewed-by: Tomas Vondra
Backpatch-through: 13
Experimentation shows that clang will auto-vectorize the critical
multiplication loop if the termination condition is written "i2 < limit"
rather than "i2 <= limit". This seems unbelievably stupid, but I've
reproduced it on both clang 9.0.1 (RHEL8) and 11.0.3 (macOS Catalina).
gcc doesn't care, so tweak the code to do it that way.
Discussion: https://postgr.es/m/CAJ3gD9evtA_vBo+WMYMyT-u=keHX7-r8p2w7OSRfXf42LTwCZQ@mail.gmail.com
Some kernels can tell us the type of a "dirent", so we can avoid a call
to stat() or lstat() in many cases. Define a new function
get_dirent_type() to contain that logic, for use by the backend and
frontend versions of walkdir(), and perhaps other callers in future.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Juan José Santamaría Flecha <juanjo.santamaria@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKG%2BFzxupGGN4GpUdbzZN%2Btn6FQPHo8w0Q%2BAPH5Wz8RG%2Bww%40mail.gmail.com
Amit Kapila