| Commit message (Collapse) | Author | Age |
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As noted by Noah Misch, my initial cut at fixing bug #11638 didn't cover
all cases where ANALYZE might be invoked in an unsafe context. We need to
test the result of IsInTransactionChain not IsTransactionBlock; which is
notationally a pain because IsInTransactionChain requires an isTopLevel
flag, which would have to be passed down through several levels of callers.
I chose to pass in_outer_xact (ie, the result of IsInTransactionChain)
rather than isTopLevel per se, as that seemed marginally more apropos
for the intermediate functions to know about.
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Nobody seemed concerned about this naming when it originally went in,
but there's a pending patch that implements the opposite of
dsm_keep_mapping, and the term "unkeep" was judged unpalatable.
"unpin" has existing precedent in the PostgreSQL code base, and the
English language, so use this terminology instead.
Per discussion, back-patch to 9.4.
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VACUUM and ANALYZE update the target table's pg_class row in-place, that is
nontransactionally. This is OK, more or less, for the statistical columns,
which are mostly nontransactional anyhow. It's not so OK for the DDL hint
flags (relhasindex etc), which might get changed in response to
transactional changes that could still be rolled back. This isn't a
problem for VACUUM, since it can't be run inside a transaction block nor
in parallel with DDL on the table. However, we allow ANALYZE inside a
transaction block, so if the transaction had earlier removed the last
index, rule, or trigger from the table, and then we roll back the
transaction after ANALYZE, the table would be left in a corrupted state
with the hint flags not set though they should be.
To fix, suppress the hint-flag updates if we are InTransactionBlock().
This is safe enough because it's always OK to postpone hint maintenance
some more; the worst-case consequence is a few extra searches of pg_index
et al. There was discussion of instead using a transactional update,
but that would change the behavior in ways that are not all desirable:
in most scenarios we're better off keeping ANALYZE's statistical values
even if the ANALYZE itself rolls back. In any case we probably don't want
to change this behavior in back branches.
Per bug #11638 from Casey Shobe. This has been broken for a good long
time, so back-patch to all supported branches.
Tom Lane and Michael Paquier, initial diagnosis by Andres Freund
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Instead of initializing a new TransInvalidationInfo for every
transaction or subtransaction, we can just do it for those
transactions or subtransactions that actually need to queue
invalidation messages. That also avoids needing to free those
entries at the end of a transaction or subtransaction that does
not generate any invalidation messages, which is by far the
common case.
Patch by me. Review by Simon Riggs and Andres Freund.
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Since we got rid of non-MVCC catalog scans, the fourth reason given for
using a non-transactional update in index_update_stats() is obsolete.
The other three are still good, so we're not going to change the code,
but fix the comment.
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Reported by MauMau.
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1. The comparison for matching terms used only the CRC to decide if there's
a match. Two different terms with the same CRC gave a match.
2. It assumed that if the second operand has more terms than the first, it's
never a match. That assumption is bogus, because there can be duplicate
terms in either operand.
Rewrite the implementation in a way that doesn't have those bugs.
Backpatch to all supported versions.
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Since we taught btree to handle ScalarArrayOpExpr quals natively (commit
9e8da0f75731aaa7605cf4656c21ea09e84d2eb1), the planner has always included
ScalarArrayOpExpr quals in index conditions if possible. However, if the
qual is for a non-first index column, this could result in an inferior plan
because we can no longer take advantage of index ordering (cf. commit
807a40c551dd30c8dd5a0b3bd82f5bbb1e7fd285). It can be better to omit the
ScalarArrayOpExpr qual from the index condition and let it be done as a
filter, so that the output doesn't need to get sorted. Indeed, this is
true for the query introduced as a test case by the latter commit.
To fix, restructure get_index_paths and build_index_paths so that we
consider paths both with and without ScalarArrayOpExpr quals in non-first
index columns. Redesign the API of build_index_paths so that it reports
what it found, saving useless second or third calls.
Report and patch by Andrew Gierth (though rather heavily modified by me).
Back-patch to 9.2 where this code was introduced, since the issue can
result in significant performance regressions compared to plans produced
by 9.1 and earlier.
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Spotted by Tom Lane.
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This file was documenting an older version of patch 0ac5ad5134; update
it to match what was really committed
Author: Florian Pflug
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Don't crash if an ispell dictionary definition contains flags but not
any compound affixes. (This isn't a security issue since only superusers
can install affix files, but still it's a bad thing.)
Also, be more careful about detecting whether an affix-file FLAG command
is old-format (ispell) or new-format (myspell/hunspell). And change the
error message about mixed old-format and new-format commands into something
intelligible.
Per bug #11770 from Emre Hasegeli. Back-patch to all supported branches.
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Testing reveals that the memory allocation we do at transaction start
has small but measurable overhead on simple transactions. To cut
down on that overhead, defer some of that work to the point when
AFTER triggers are first used, thus avoiding it altogether if they
never are.
Patch by me. Review by Andres Freund.
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Previously, this was not exposed outside of miscinit.c. It is needed
for the pending pg_background patch, and will also be needed for
parallelism. Without it, there's no way for a background worker to
re-create the exact authentication environment that was present in the
process that started it, which could lead to security exposures.
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Previously the archive recovery always created .ready file for
the last WAL file of the old timeline at the end of recovery even when
it's restored from the archive and has .done file. That is, there was
the case where the WAL file had both .ready and .done files.
This caused the already-archived WAL file to be archived again.
This commit prevents the archive recovery from creating .ready file
for the last WAL file if it has .done file, in order to prevent it from
being archived again.
This bug was added when cascading replication feature was introduced,
i.e., the commit 5286105800c7d5902f98f32e11b209c471c0c69c.
So, back-patch to 9.2, where cascading replication was added.
Reviewed by Michael Paquier
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In a couple of code paths, pg_class_aclcheck is called in succession
with multiple different modes set. This patch combines those modes to
have a single call of this function and reduce a bit process overhead
for permission checking.
Author: Michael Paquier <michael@otacoo.com>
Reviewed-by: Fabrízio de Royes Mello <fabriziomello@gmail.com>
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The _bt_tuplecompare() function mentioned in comment hasn't existed for a
long time.
Peter Geoghegan
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Author: Herwin Weststrate <herwin@quarantainenet.nl>
Reviewed-by: Ali Akbar <the.apaan@gmail.com>
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The duplication originated in cdd46c765, where restartpoints were
introduced.
In LogCheckpointStart's case the duplication actually lead to the
compiler's format string checking not to be effective because the
format string wasn't constant.
Arguably these messages shouldn't be elog(), but ereport() style
messages. That'd even allow to translate the messages... But as
there's more mistakes of that kind in surrounding code, it seems
better to change that separately.
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Commit 7dbb6069382 added a new CHECKPOINT_FLUSH_ALL flag. As that
commit needed to be backpatched I didn't change the numeric values of
the existing flags as that could lead to nastly problems if any
external code issued checkpoints. That's not a concern on master, so
renumber them there.
Also add a comment about CHECKPOINT_FLUSH_ALL above
CreateCheckPoint().
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CREATE DATABASE and ALTER DATABASE .. SET TABLESPACE copy the source
database directory on the filesystem level. To ensure the on disk
state is consistent they block out users of the affected database and
force a checkpoint to flush out all data to disk. Unfortunately, up to
now, that checkpoint didn't flush out dirty buffers from unlogged
relations.
That bug means there could be leftover dirty buffers in either the
template database, or the database in its old location. Leading to
problems when accessing relations in an inconsistent state; and to
possible problems during shutdown in the SET TABLESPACE case because
buffers belonging files that don't exist anymore are flushed.
This was reported in bug #10675 by Maxim Boguk.
Fix by Pavan Deolasee, modified somewhat by me. Reviewed by MauMau and
Fujii Masao.
Backpatch to 9.1 where unlogged tables were introduced.
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If an inline-able SQL function taking a composite argument is used in a
LATERAL subselect, and the composite argument is a lateral reference,
the planner could fail with "variable not found in subplan target list",
as seen in bug #11703 from Karl Bartel. (The outer function call used in
the bug report and in the committed regression test is not really necessary
to provoke the bug --- you can get it if you manually expand the outer
function into "LATERAL (SELECT inner_function(outer_relation))", too.)
The cause of this is that we generate the reltargetlist for the referenced
relation before doing eval_const_expressions() on the lateral sub-select's
expressions (cf find_lateral_references()), so what's scheduled to be
emitted by the referenced relation is a whole-row Var, not the simplified
single-column Var produced by optimizing the function's FieldSelect on the
whole-row Var. Then setrefs.c fails to match up that lateral reference to
what's available from the outer scan.
Preserving the FieldSelect optimization in such cases would require either
major planner restructuring (to recursively do expression simplification
on sub-selects much earlier) or some amazingly ugly kluge to change the
reltargetlist of a possibly-already-planned relation. It seems better
just to skip the optimization when the Var is from an upper query level;
the case is not so common that it's likely anyone will notice a few
wasted cycles.
AFAICT this problem only occurs for uplevel LATERAL references, so
back-patch to 9.3 where LATERAL was added.
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David Rowley
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Etsuro Fujita
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This matches the behavior of other parameters that are unsupported on
some systems (e.g., ssl).
Also document the default value.
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Also document that PITR is also affected.
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interval precision can only be specified after the "interval" keyword if
no units are specified.
Previously we incorrectly checked the units to see if the precision was
legal, causing confusion.
Report by Alvaro Herrera
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Nearly all Paths have parents, but a ResultPath representing an empty FROM
clause does not. Avoid a core dump in such cases. I believe this is only
a hazard for debugging usage, not for production, else we'd have heard
about it before. Nonetheless, back-patch to 9.1 where the troublesome code
was introduced. Noted while poking at bug #11703.
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Up to now, PG has assumed that any given timezone abbreviation (such as
"EDT") represents a constant GMT offset in the usage of any particular
region; we had a way to configure what that offset was, but not for it
to be changeable over time. But, as with most things horological, this
view of the world is too simplistic: there are numerous regions that have
at one time or another switched to a different GMT offset but kept using
the same timezone abbreviation. Almost the entire Russian Federation did
that a few years ago, and later this month they're going to do it again.
And there are similar examples all over the world.
To cope with this, invent the notion of a "dynamic timezone abbreviation",
which is one that is referenced to a particular underlying timezone
(as defined in the IANA timezone database) and means whatever it currently
means in that zone. For zones that use or have used daylight-savings time,
the standard and DST abbreviations continue to have the property that you
can specify standard or DST time and get that time offset whether or not
DST was theoretically in effect at the time. However, the abbreviations
mean what they meant at the time in question (or most recently before that
time) rather than being absolutely fixed.
The standard abbreviation-list files have been changed to use this behavior
for abbreviations that have actually varied in meaning since 1970. The
old simple-numeric definitions are kept for abbreviations that have not
changed, since they are a bit faster to resolve.
While this is clearly a new feature, it seems necessary to back-patch it
into all active branches, because otherwise use of Russian zone
abbreviations is going to become even more problematic than it already was.
This change supersedes the changes in commit 513d06ded et al to modify the
fixed meanings of the Russian abbreviations; since we've not shipped that
yet, this will avoid an undesirably incompatible (not to mention incorrect)
change in behavior for timestamps between 2011 and 2014.
This patch makes some cosmetic changes in ecpglib to keep its usage of
datetime lookup tables as similar as possible to the backend code, but
doesn't do anything about the increasingly obsolete set of timezone
abbreviation definitions that are hard-wired into ecpglib. Whatever we
do about that will likely not be appropriate material for back-patching.
Also, a potential free() of a garbage pointer after an out-of-memory
failure in ecpglib has been fixed.
This patch also fixes pre-existing bugs in DetermineTimeZoneOffset() that
caused it to produce unexpected results near a timezone transition, if
both the "before" and "after" states are marked as standard time. We'd
only ever thought about or tested transitions between standard and DST
time, but that's not what's happening when a zone simply redefines their
base GMT offset.
In passing, update the SGML documentation to refer to the Olson/zoneinfo/
zic timezone database as the "IANA" database, since it's now being
maintained under the auspices of IANA.
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We've gotten enough push-back on that change to make it clear that it
wasn't an especially good idea to do it like that. Revert plain EXPLAIN
to its previous behavior, but keep the extra output in EXPLAIN ANALYZE.
Per discussion.
Internally, I set this up as a separate flag ExplainState.summary that
controls printing of planning time and execution time. For now it's
just copied from the ANALYZE option, but we could consider exposing it
to users.
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LWLockRelease should release all backends waiting with LWLockWaitForVar,
even when another backend has already been woken up to acquire the lock,
i.e. when releaseOK is false. LWLockWaitForVar can return as soon as the
protected value changes, even if the other backend will acquire the lock.
Fix that by resetting releaseOK to true in LWLockWaitForVar, whenever
adding itself to the wait queue.
This should fix the bug reported by MauMau, where the system occasionally
hangs when there is a lot of concurrent WAL activity and a checkpoint.
Backpatch to 9.4, where this code was added.
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Report by Peter Geoghegan
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Patch by Euler Taveira
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If we expect batching at the very beginning, we size nbuckets for
"full work_mem" (see how many tuples we can get into work_mem,
while not breaking NTUP_PER_BUCKET threshold).
If we expect to be fine without batching, we start with the 'right'
nbuckets and track the optimal nbuckets as we go (without actually
resizing the hash table). Once we hit work_mem (considering the
optimal nbuckets value), we keep the value.
At the end of the first batch, we check whether (nbuckets !=
nbuckets_optimal) and resize the hash table if needed. Also, we
keep this value for all batches (it's OK because it assumes full
work_mem, and it makes the batchno evaluation trivial). So the
resize happens only once.
There could be cases where it would improve performance to allow
the NTUP_PER_BUCKET threshold to be exceeded to keep everything in
one batch rather than spilling to a second batch, but attempts to
generate such a case have so far been unsuccessful; that issue may
be addressed with a follow-on patch after further investigation.
Tomas Vondra with minor format and comment cleanup by me
Reviewed by Robert Haas, Heikki Linnakangas, and Kevin Grittner
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When determining whether one JSONB object contains another, it's okay to
make a quick exit if the first object has fewer pairs than the second:
because we de-duplicate keys within objects, it is impossible that the
first object has all the keys the second does. However, the code was
applying this rule to JSONB arrays as well, where it does *not* hold
because arrays can contain duplicate entries. The test was really in
the wrong place anyway; we should do it within JsonbDeepContains, where
it can be applied to nested objects not only top-level ones.
Report and test cases by Alexander Korotkov; fix by Peter Geoghegan and
Tom Lane.
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The new header contains many prototypes for functions in ruleutils.c
that are not exposed to the SQL level.
Reviewed by Andres Freund and Michael Paquier.
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shm_mq_sendv sends a message to the queue assembled from multiple
locations. This is expected to be used by forthcoming patches to
allow frontend/backend protocol messages to be sent via shm_mq, but
might be useful for other purposes as well.
shm_mq_set_handle associates a BackgroundWorkerHandle with an
already-existing shm_mq_handle. This solves a timing problem when
creating a shm_mq to communicate with a newly-launched background
worker: if you attach to the queue first, and the background worker
fails to start, you might block forever trying to do I/O on the queue;
but if you start the background worker first, but then die before
attaching to the queue, the background worrker might block forever
trying to do I/O on the queue. This lets you attach before starting
the worker (so that the worker is protected) and then associate the
BackgroundWorkerHandle later (so that you are also protected).
Patch by me, reviewed by Stephen Frost.
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This clause changes the behavior of SELECT locking clauses in the
presence of locked rows: instead of causing a process to block waiting
for the locks held by other processes (or raise an error, with NOWAIT),
SKIP LOCKED makes the new reader skip over such rows. While this is not
appropriate behavior for general purposes, there are some cases in which
it is useful, such as queue-like tables.
Catalog version bumped because this patch changes the representation of
stored rules.
Reviewed by Craig Ringer (based on a previous attempt at an
implementation by Simon Riggs, who also provided input on the syntax
used in the current patch), David Rowley, and Álvaro Herrera.
Author: Thomas Munro
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Teach sigusr1_handler() to use the same test for whether a worker
might need to be started as ServerLoop(). Aside from being perhaps
a bit simpler, this prevents a potentially-unbounded delay when
starting a background worker. On some platforms, select() doesn't
return when interrupted by a signal, but is instead restarted,
including a reset of the timeout to the originally-requested value.
If signals arrive often enough, but no connection requests arrive,
sigusr1_handler() will be executed repeatedly, but the body of
ServerLoop() won't be reached. This change ensures that, even in
that case, background workers will eventually get launched.
This is far from a perfect fix; really, we need select() to return
control to ServerLoop() after an interrupt, either via the self-pipe
trick or some other mechanism. But that's going to require more
work and discussion, so let's do this for now to at least mitigate
the damage.
Per investigation of test_shm_mq failures on buildfarm member anole.
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Most zones in the Russian Federation are subtracting one or two hours
as of 2014-10-26. Update the meanings of the abbreviations IRKT, KRAT,
MAGT, MSK, NOVT, OMST, SAKT, VLAT, YAKT, YEKT to match.
The IANA timezone database has adopted abbreviations of the form AxST/AxDT
for all Australian time zones, reflecting what they believe to be current
majority practice Down Under. These names do not conflict with usage
elsewhere (other than ACST for Acre Summer Time, which has been in disuse
since 1994). Accordingly, adopt these names into our "Default" timezone
abbreviation set. The "Australia" abbreviation set now contains only
CST,EAST,EST,SAST,SAT,WST, all of which are thought to be mostly historical
usage. Note that SAST has also been changed to be South Africa Standard
Time in the "Default" abbreviation set.
Add zone abbreviations SRET (Asia/Srednekolymsk) and XJT (Asia/Urumqi),
and use WSST/WSDT for western Samoa.
Also a DST law change in the Turks & Caicos Islands (America/Grand_Turk),
and numerous corrections for historical time zone data.
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Peter G pointed out that valgrind was, rightfully, complaining about
CreatePolicy() ending up copying beyond the end of the parsed policy
name. Name is a fixed-size type and we need to use namein (through
DirectFunctionCall1()) to flush out the entire array before we pass
it down to heap_form_tuple.
Michael Paquier pointed out that pg_dump --verbose was missing a
newline and Fabrízio de Royes Mello further pointed out that the
schema was also missing from the messages, so fix those also.
Also, based on an off-list comment from Kevin, rework the psql \d
output to facilitate copy/pasting into a new CREATE or ALTER POLICY
command.
Lastly, improve the pg_policies view and update the documentation for
it, along with a few other minor doc corrections based on an off-list
discussion with Adam Brightwell.
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When there are cost-delay-related storage options set for a table,
trying to make that table participate in the autovacuum cost-limit
balancing algorithm produces undesirable results: instead of using the
configured values, the global values are always used,
as illustrated by Mark Kirkwood in
http://www.postgresql.org/message-id/52FACF15.8020507@catalyst.net.nz
Since the mechanism is already complicated, just disable it for those
cases rather than trying to make it cope. There are undesirable
side-effects from this too, namely that the total I/O impact on the
system will be higher whenever such tables are vacuumed. However, this
is seen as less harmful than slowing down vacuum, because that would
cause bloat to accumulate. Anyway, in the new system it is possible to
tweak options to get the precise behavior one wants, whereas with the
previous system one was simply hosed.
This has been broken forever, so backpatch to all supported branches.
This might affect systems where cost_limit and cost_delay have been set
for individual tables.
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Etsuro Fujita
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The page splitting code would go into infinite recursion if you try to
insert an index tuple that doesn't fit even on an empty page.
Per analysis and suggested fix by Andrew Gierth. Fixes bug #11555, reported
by Bryan Seitz (analysis happened over IRC). Backpatch to all supported
versions.
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Testing by Amit Kapila, Andres Freund, and myself, with and without
other patches that also aim to improve scalability, seems to indicate
that this change is a significant win over the current value and over
smaller values such as 64. It's not clear how high we can push this
value before it starts to have negative side-effects elsewhere, but
going this far looks OK.
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As of commit a87c72915 (which later got backpatched as far as 9.1),
we're explicitly supporting the notion that append relations can be
nested; this can occur when UNION ALL constructs are nested, or when
a UNION ALL contains a table with inheritance children.
Bug #11457 from Nelson Page, as well as an earlier report from Elvis
Pranskevichus, showed that there were still nasty bugs associated with such
cases: in particular the EquivalenceClass mechanism could try to generate
"join" clauses connecting an appendrel child to some grandparent appendrel,
which would result in assertion failures or bogus plans.
Upon investigation I concluded that all current callers of
find_childrel_appendrelinfo() need to be fixed to explicitly consider
multiple levels of parent appendrels. The most complex fix was in
processing of "broken" EquivalenceClasses, which are ECs for which we have
been unable to generate all the derived equality clauses we would like to
because of missing cross-type equality operators in the underlying btree
operator family. That code path is more or less entirely untested by
the regression tests to date, because no standard opfamilies have such
holes in them. So I wrote a new regression test script to try to exercise
it a bit, which turned out to be quite a worthwhile activity as it exposed
existing bugs in all supported branches.
The present patch is essentially the same as far back as 9.2, which is
where parameterized paths were introduced. In 9.0 and 9.1, we only need
to back-patch a small fragment of commit 5b7b5518d, which fixes failure to
propagate out the original WHERE clauses when a broken EC contains constant
members. (The regression test case results show that these older branches
are noticeably stupider than 9.2+ in terms of the quality of the plans
generated; but we don't really care about plan quality in such cases,
only that the plan not be outright wrong. A more invasive fix in the
older branches would not be a good idea anyway from a plan-stability
standpoint.)
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I left the GUC in place for the beta period, so that people could experiment
with different values. No-one's come up with any data that a different value
would be better under some circumstances, so rather than try to document to
users what the GUC, let's just hard-code the current value, 8.
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DetermineSleepTime() was previously called without blocked
signals. That's not good, because it allows signal handlers to
interrupt its workings.
DetermineSleepTime() was added in 9.3 with the addition of background
workers (da07a1e856511), where it only read from
BackgroundWorkerList.
Since 9.4, where dynamic background workers were added (7f7485a0cde),
the list is also manipulated in DetermineSleepTime(). That's bad
because the list now can be persistently corrupted if modified by both
a signal handler and DetermineSleepTime().
This was discovered during the investigation of hangs on buildfarm
member anole. It's unclear whether this bug is the source of these
hangs or not, but it's worth fixing either way. I have confirmed that
it can cause crashes.
It luckily looks like this only can cause problems when bgworkers are
actively used.
Discussion: 20140929193733.GB14400@awork2.anarazel.de
Backpatch to 9.3 where background workers were introduced.
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