Tom Lane [Sun, 1 Sep 2013 23:43:02 +0000 (19:43 -0400)]
Update "Using EXPLAIN" documentation examples using current code.
It seems like a good idea to update these examples since some fairly
basic planner behaviors have changed in 9.3; notably that the startup cost
for an indexscan plan node is no longer invariably estimated at 0.00.
Tom Lane [Fri, 30 Aug 2013 23:15:21 +0000 (19:15 -0400)]
Reset the binary heap in MergeAppend rescans.
Failing to do so can cause queries to return wrong data, error out or crash.
This requires adding a new binaryheap_reset() method to binaryheap.c,
but that probably should have been there anyway.
Per bug #8410 from Terje Elde. Diagnosis and patch by Andres Freund.
Use a non-locking initial test in TAS_SPIN on x86_64.
Testing done in 2011 by Tom Lane concluded that this is a win on Intel Xeons
and AMD Opterons, but it was not changed back then, because of an old
comment in tas() that suggested that it's a huge loss on older Opterons.
However, didn't have separate TAS() and TAS_SPIN() macros back then, so the
comment referred to doing a non-locked initial test even on the first
access, in uncontended case. I don't have access to older Opterons, but I'm
pretty sure that doing an initial unlocked test is unlikely to be a loss
while spinning, even though it might be for the first access.
We probably should do the same on 32-bit x86, but I'm afraid of changing it
without any testing. Hence just add a note to the x86 implementation
suggesting that we probably should do the same there.
Robert Haas [Wed, 28 Aug 2013 18:08:13 +0000 (14:08 -0400)]
Allow discovery of whether a dynamic background worker is running.
Using the infrastructure provided by this patch, it's possible either
to wait for the startup of a dynamically-registered background worker,
or to poll the status of such a worker without waiting. In either
case, the current PID of the worker process can also be obtained.
As usual, worker_spi is updated to demonstrate the new functionality.
As noted by Tom Lane, commit 813fb0315587d32e3b77af1051a0ef517d187763
was overly optimistic about how safe it is to concurrently change
enumsortorder values under MVCC catalog scan semantics. Restore
some of the previous text, with hopefully-correct adjustments for
the new state of play.
Tom Lane [Sat, 24 Aug 2013 19:14:17 +0000 (15:14 -0400)]
Account better for planning cost when choosing whether to use custom plans.
The previous coding in plancache.c essentially used 10% of the estimated
runtime as its cost estimate for planning. This can be pretty bogus,
especially when the estimated runtime is very small, such as in a simple
expression plan created by plpgsql, or a simple INSERT ... VALUES.
While we don't have a really good handle on how planning time compares
to runtime, it seems reasonable to use an estimate based on the number of
relations referenced in the query, with a rather large multiplier. This
patch uses 1000 * cpu_operator_cost * (nrelations + 1), so that even a
trivial query will be charged 1000 * cpu_operator_cost for planning.
This should address the problem reported by Marc Cousin and others that
9.2 and up prefer custom plans in cases where the planning time greatly
exceeds what can be saved.
Magnus Hagander [Sat, 24 Aug 2013 15:11:31 +0000 (17:11 +0200)]
Don't crash when pg_xlog is empty and pg_basebackup -x is used
The backup will not work (without a logarchive, and that's the whole
point of -x) in this case, this patch just changes it to throw an
error instead of crashing when this happens.
Tom Lane [Fri, 23 Aug 2013 21:30:53 +0000 (17:30 -0400)]
In locate_grouping_columns(), don't expect an exact match of Var typmods.
It's possible that inlining of SQL functions (or perhaps other changes?)
has exposed typmod information not known at parse time. In such cases,
Vars generated by query_planner might have valid typmod values while the
original grouping columns only have typmod -1. This isn't a semantic
problem since the behavior of grouping only depends on type not typmod,
but it breaks locate_grouping_columns' use of tlist_member to locate the
matching entry in query_planner's result tlist.
We can fix this without an excessive amount of new code or complexity by
relying on the fact that locate_grouping_columns only gets called when
make_subplanTargetList has set need_tlist_eval == false, and that can only
happen if all the grouping columns are simple Vars. Therefore we only need
to search the sub_tlist for a matching Var, and we can reasonably define a
"match" as being a match of the Var identity fields
varno/varattno/varlevelsup. The code still Asserts that vartype matches,
but ignores vartypmod.
Per bug #8393 from Evan Martin. The added regression test case is
basically the same as his example. This has been broken for a very long
time, so back-patch to all supported branches.
Tom Lane [Wed, 21 Aug 2013 17:38:16 +0000 (13:38 -0400)]
Fix hash table size estimation error in choose_hashed_distinct().
We should account for the per-group hashtable entry overhead when
considering whether to use a hash aggregate to implement DISTINCT. The
comparable logic in choose_hashed_grouping() gets this right, but I think
I omitted it here in the mistaken belief that there would be no overhead
if there were no aggregate functions to be evaluated. This can result in
more than 2X underestimate of the hash table size, if the tuples being
aggregated aren't very wide. Per report from Tomas Vondra.
This bug is of long standing, but per discussion we'll only back-patch into
9.3. Changing the estimation behavior in stable branches seems to carry too
much risk of destabilizing plan choices for already-tuned applications.
Andrew Dunstan [Tue, 20 Aug 2013 18:11:36 +0000 (14:11 -0400)]
Unconditionally use the WSA equivalents of Socket error constants.
This change will only apply to mingw compilers, and has been found
necessary by late versions of the mingw-w64 compiler. It's the same as
what is done elsewhere for the Microsoft compilers.
If this doesn't upset older compilers in the buildfarm, it will be
backpatched to 9.1.
Problem reported by Michael Cronenworth, although not his patch.
Alvaro Herrera [Mon, 19 Aug 2013 21:48:17 +0000 (17:48 -0400)]
Fix removal of files in pgstats directories
Instead of deleting all files in stats_temp_directory and the permanent
directory on a crash, only remove those files that match the pattern of
files we actually write in them, to avoid possibly clobbering existing
unrelated contents of the temporary directory. Per complaint from Jeff
Janes, and subsequent discussion, starting at message
CAMkU=1z9+7RsDODnT4=cDFBRBp8wYQbd_qsLcMtKEf-oFwuOdQ@mail.gmail.com
Also, fix a bug in the same routine to avoid removing files from the
permanent directory twice (instead of once from that directory and then
from the temporary directory), also per report from Jeff Janes, in
message
CAMkU=1wbk947=-pAosDMX5VC+sQw9W4ttq6RM9rXu=MjNeEQKA@mail.gmail.com
This keeps the usual trigger file name unchanged from 9.2, avoiding nasty
issues if you use a pre-9.3 pg_ctl binary with a 9.3 server or vice versa.
The fallback behavior of creating a full checkpoint before starting up is now
triggered by a file called "fallback_promote". That can be useful for
debugging purposes, but we don't expect any users to have to resort to that
and we might want to remove that in the future, which is why the fallback
mechanism is undocumented.
Tom Lane [Mon, 19 Aug 2013 17:19:25 +0000 (13:19 -0400)]
Fix qual-clause-misplacement issues with pulled-up LATERAL subqueries.
In an example such as
SELECT * FROM
i LEFT JOIN LATERAL (SELECT * FROM j WHERE i.n = j.n) j ON true;
it is safe to pull up the LATERAL subquery into its parent, but we must
then treat the "i.n = j.n" clause as a qual clause of the LEFT JOIN. The
previous coding in deconstruct_recurse mistakenly labeled the clause as
"is_pushed_down", resulting in wrong semantics if the clause were applied
at the join node, as per an example submitted awhile ago by Jeremy Evans.
To fix, postpone processing of such clauses until we return back up to
the appropriate recursion depth in deconstruct_recurse.
In addition, tighten the is-safe-to-pull-up checks in is_simple_subquery;
we previously missed the possibility that the LATERAL subquery might itself
contain an outer join that makes lateral references in lower quals unsafe.
A regression test case equivalent to Jeremy's example was already in my
commit of yesterday, but was giving the wrong results because of this
bug. This patch fixes the expected output for that, and also adds a
test case for the second problem.
Alvaro Herrera [Mon, 19 Aug 2013 16:33:07 +0000 (12:33 -0400)]
Fix pg_upgrade failure from servers older than 9.3
When upgrading from servers of versions 9.2 and older, and MultiXactIds
have been used in the old server beyond the first page (that is, 2048
multis or more in the default 8kB-page build), pg_upgrade would set the
next multixact offset to use beyond what has been allocated in the new
cluster. This would cause a failure the first time the new cluster
needs to use this value, because the pg_multixact/offsets/ file wouldn't
exist or wouldn't be large enough. To fix, ensure that the transient
server instances launched by pg_upgrade extend the file as necessary.
Per report from Jesse Denardo in
CANiVXAj4c88YqipsyFQPboqMudnjcNTdB3pqe8ReXqAFQ=HXyA@mail.gmail.com
Kevin Grittner [Sun, 18 Aug 2013 21:19:22 +0000 (16:19 -0500)]
Remove relcache entry invalidation in REFRESH MATERIALIZED VIEW.
This was added as part of the attempt to support unlogged matviews
along with a populated status. It got missed when unlogged
support was removed pre-commit.
Noticed by Noah Misch. Back-patched to 9.3 branch.
Tom Lane [Sun, 18 Aug 2013 00:22:37 +0000 (20:22 -0400)]
Fix planner problems with LATERAL references in PlaceHolderVars.
The planner largely failed to consider the possibility that a
PlaceHolderVar's expression might contain a lateral reference to a Var
coming from somewhere outside the PHV's syntactic scope. We had a previous
report of a problem in this area, which I tried to fix in a quick-hack way
in commit 4da6439bd8553059766011e2a42c6e39df08717f, but Antonin Houska
pointed out that there were still some problems, and investigation turned
up other issues. This patch largely reverts that commit in favor of a more
thoroughly thought-through solution. The new theory is that a PHV's
ph_eval_at level cannot be higher than its original syntactic level. If it
contains lateral references, those don't change the ph_eval_at level, but
rather they create a lateral-reference requirement for the ph_eval_at join
relation. The code in joinpath.c needs to handle that.
Another issue is that createplan.c wasn't handling nested PlaceHolderVars
properly.
In passing, push knowledge of lateral-reference checks for join clauses
into join_clause_is_movable_to. This is mainly so that FDWs don't need
to deal with it.
This patch doesn't fix the original join-qual-placement problem reported by
Jeremy Evans (and indeed, one of the new regression test cases shows the
wrong answer because of that). But the PlaceHolderVar problems need to be
fixed before that issue can be addressed, so committing this separately
seems reasonable.
Tom Lane [Wed, 14 Aug 2013 22:38:32 +0000 (18:38 -0400)]
Remove ph_may_need from PlaceHolderInfo, with attendant simplifications.
The planner logic that attempted to make a preliminary estimate of the
ph_needed levels for PlaceHolderVars seems to be completely broken by
lateral references. Fortunately, the potential join order optimization
that this code supported seems to be of relatively little value in
practice; so let's just get rid of it rather than trying to fix it.
Getting rid of this allows fairly substantial simplifications in
placeholder.c, too, so planning in such cases should be a bit faster.
Issue noted while pursuing bugs reported by Jeremy Evans and Antonin
Houska, though this doesn't in itself fix either of their reported cases.
What this does do is prevent an Assert crash in the kind of query
illustrated by the added regression test. (I'm not sure that the plan for
that query is stable enough across platforms to be usable as a regression
test output ... but we'll soon find out from the buildfarm.)
Back-patch to 9.3. The problem case can't arise without LATERAL, so
no need to touch older branches.
Peter Eisentraut [Wed, 14 Aug 2013 00:08:44 +0000 (20:08 -0400)]
Update Emacs configuration
Update emacs.samples with new configuration snippets that match pgindent
et al. formatting more accurately and follow Emacs Lisp best practices
better.
Add .dir-locals.el with a subset of that configuration for casual
editing and viewing.
Tom Lane [Tue, 13 Aug 2013 19:24:52 +0000 (15:24 -0400)]
Emit a log message if output is about to be redirected away from stderr.
We've seen multiple cases of people looking at the postmaster's original
stderr output to try to diagnose problems, not realizing/remembering that
their logging configuration is set up to send log messages somewhere else.
This seems particularly likely to happen in prepackaged distributions,
since many packagers patch the code to change the factory-standard logging
configuration to something more in line with their platform conventions.
In hopes of reducing confusion, emit a LOG message about this at the point
in startup where we are about to switch log output away from the original
stderr, providing a pointer to where to look instead. This message will
appear as the last thing in the original stderr output. (We might later
also try to emit such link messages when logging parameters are changed
on-the-fly; but that case seems to be both noticeably harder to do nicely,
and much less frequently a problem in practice.)
Per discussion, back-patch to 9.3 but not further.
Peter Eisentraut [Sun, 11 Aug 2013 13:17:04 +0000 (09:17 -0400)]
PL/Python: Adjust the regression tests for Python 3.3
Similar to 2cfb1c6f77734db81b6e74bcae630f93b94f69be, the order in which
dictionary elements are printed is not reliable. This reappeared in the
tests of the string representation of result objects. Reduce the test
case to one result set column so that there is no question of order.
Fujii Masao [Wed, 7 Aug 2013 17:48:53 +0000 (02:48 +0900)]
Fix assertion failure by an immediate shutdown.
In PM_WAIT_DEAD_END state, checkpointer process must be dead already.
But an immediate shutdown could make postmaster's state machine
transition to PM_WAIT_DEAD_END state even if checkpointer process is
still running, and which caused assertion failure. This bug was introduced
in commit 457d6cf049c57cabe9b46ea13f26138040a214ec.
This patch ensures that postmaster's state machine doesn't transition to
PM_WAIT_DEAD_END state in an immediate shutdown while checkpointer
process is running.
Tom Lane [Mon, 5 Aug 2013 19:00:57 +0000 (15:00 -0400)]
Simplify query_planner's API by having it return the top-level RelOptInfo.
Formerly, query_planner returned one or possibly two Paths for the topmost
join relation, so that grouping_planner didn't see the join RelOptInfo
(at least not directly; it didn't have any hesitation about examining
cheapest_path->parent, though). However, correct selection of the Paths
involved a significant amount of coupling between query_planner and
grouping_planner, a problem which has gotten worse over time. It seems
best to give up on this API choice and instead return the topmost
RelOptInfo explicitly. Then grouping_planner can pull out the Paths it
wants from the rel's path list. In this way we can remove all knowledge
of grouping behaviors from query_planner.
The only real benefit of the old way is that in the case of an empty
FROM clause, we never made any RelOptInfos at all, just a Path. Now
we have to gin up a dummy RelOptInfo to represent the empty FROM clause.
That's not a very big deal though.
While at it, simplify query_planner's API a bit more by having the caller
set up root->tuple_fraction and root->limit_tuples, rather than passing
those values as separate parameters. Since query_planner no longer does
anything with either value, requiring it to fill the PlannerInfo fields
seemed pretty arbitrary.
This patch just rearranges code; it doesn't (intentionally) change any
behaviors. Followup patches will do more interesting things.
Kevin Grittner [Mon, 5 Aug 2013 14:57:56 +0000 (09:57 -0500)]
Various cleanups for REFRESH MATERIALIZED VIEW CONCURRENTLY.
Open and lock each index before checking definition in RMVC. The
ExclusiveLock on the related table is not viewed as sufficient to
ensure that no changes are made to the index definition, and
invalidation messages from other backends might have been missed.
Additionally, use RelationGetIndexExpressions() and check for NIL
rather than doing our own loop.
Protect against redefinition of tid and rowvar operators in RMVC.
While working on this, noticed that the fixes for bugs found during
the CF made the UPDATE statement useless, since no rows could
qualify for that treatment any more. Ripping out code to support
the UPDATE statement simplified the operator cleanups.
Change slightly confusing local field name.
Use meaningful alias names on queries in refresh_by_match_merge().
Per concerns of raised by Andres Freund and comments and
suggestions from Noah Misch. Some additional issues remain, which
will be addressed separately.
Tom Lane [Sat, 3 Aug 2013 16:39:47 +0000 (12:39 -0400)]
Make sure float4in/float8in accept all standard spellings of "infinity".
The C99 and POSIX standards require strtod() to accept all these spellings
(case-insensitively): "inf", "+inf", "-inf", "infinity", "+infinity",
"-infinity". However, pre-C99 systems might accept only some or none of
these, and apparently Windows still doesn't accept "inf". To avoid
surprising cross-platform behavioral differences, manually check for each
of these spellings if strtod() fails. We were previously handling just
"infinity" and "-infinity" that way, but since C99 is most of the world
now, it seems likely that applications are expecting all these spellings
to work.
Per bug #8355 from Basil Peace. It turns out this fix won't actually
resolve his problem, because Python isn't being this careful; but that
doesn't mean we shouldn't be.
Alvaro Herrera [Fri, 2 Aug 2013 18:34:56 +0000 (14:34 -0400)]
Fix old visibility bug in HeapTupleSatisfiesDirty
If a tuple is locked but not updated by a concurrent transaction,
HeapTupleSatisfiesDirty would return that transaction's Xid in xmax,
causing callers to wait on it, when it is not necessary (in fact, if the
other transaction had used a multixact instead of a plain Xid to mark
the tuple, HeapTupleSatisfiesDirty would have behave differently and
*not* returned the Xmax).
This bug was introduced in commit 3f7fbf85dc5b42, dated December 1998,
so it's almost 15 years old now. However, it's hard to see this
misbehave, because before we had NOWAIT the only consequence of this is
that transactions would wait for slightly more time than necessary; so
it's not surprising that this hasn't been reported yet.
Alvaro Herrera [Fri, 2 Aug 2013 16:49:03 +0000 (12:49 -0400)]
Fix crash in error report of invalid tuple lock
My tweak of these error messages in commit c359a1b082 contained the
thinko that a query would always have rowMarks set for a query
containing a locking clause. Not so: when declaring a cursor, for
instance, rowMarks isn't set at the point we're checking, so we'd be
dereferencing a NULL pointer.
The fix is to pass the lock strength to the function raising the error,
instead of trying to reverse-engineer it. The result not only is more
robust, but it also seems cleaner overall.
Bruce Momjian [Fri, 2 Aug 2013 04:45:19 +0000 (00:45 -0400)]
pg_test_fsync: expand ops/sec display
Expand ops/sec by two digits to maintain alignment on servers with fast
I/O subsystems, e.g. can now display < 10M ops/sec with consistent
alignment.
Stephen Frost [Thu, 1 Aug 2013 19:42:07 +0000 (15:42 -0400)]
Improve handling of pthread_mutex_lock error case
We should really be reporting a useful error along with returning
a valid return code if pthread_mutex_lock() throws an error for
some reason. Add that and back-patch to 9.0 as the prior patch.
Robert Haas [Thu, 1 Aug 2013 14:46:19 +0000 (10:46 -0400)]
Remove SnapshotNow and HeapTupleSatisfiesNow.
We now use MVCC catalog scans, and, per discussion, have eliminated
all other remaining uses of SnapshotNow, so that we can now get rid of
it. This will break third-party code which is still using it, which
is intentional, as we want such code to be updated to do things the
new way.
Stephen Frost [Thu, 1 Aug 2013 05:15:45 +0000 (01:15 -0400)]
Add locking around SSL_context usage in libpq
I've been working with Nick Phillips on an issue he ran into when
trying to use threads with SSL client certificates. As it turns out,
the call in initialize_SSL() to SSL_CTX_use_certificate_chain_file()
will modify our SSL_context without any protection from other threads
also calling that function or being at some other point and trying to
read from SSL_context.
To protect against this, I've written up the attached (based on an
initial patch from Nick and much subsequent discussion) which puts
locks around SSL_CTX_use_certificate_chain_file() and all of the other
users of SSL_context which weren't already protected.
Nick Phillips, much reworked by Stephen Frost
Back-patch to 9.0 where we started loading the cert directly instead of
using a callback.
Stephen Frost [Thu, 1 Aug 2013 05:07:20 +0000 (01:07 -0400)]
Allow a context to be passed in for error handling
As pointed out by Tom Lane, we can allow other users of the error
handler callbacks to provide their own memory context by adding
the context to use to ErrorData and using that instead of explicitly
using ErrorContext.
This then allows GetErrorContextStack() to be called from inside
exception handlers, so modify plpgsql to take advantage of that and
add an associated regression test for it.
Tom Lane [Wed, 31 Jul 2013 15:31:22 +0000 (11:31 -0400)]
Fix regexp_matches() handling of zero-length matches.
We'd find the same match twice if it was of zero length and not immediately
adjacent to the previous match. replace_text_regexp() got similar cases
right, so adjust this search logic to match that. Note that even though
the regexp_split_to_xxx() functions share this code, they did not display
equivalent misbehavior, because the second match would be considered
degenerate and ignored.
Currently we don't need to update the pg_tablespace catalog
after redefining the symbolic links to the tablespaces
because pg_tablespace.spclocation column was removed in
PostgreSQL 9.2.
Back patch to 9.2 where pg_tablespace.spclocation was removed.
Refactoring as part of commit 8ceb24568054232696dddc1166a8563bc78c900a
had the unintended effect of making REINDEX TABLE and REINDEX DATABASE
no longer validate constraints enforced by the indexes in question;
REINDEX INDEX still did so. Indexes marked invalid remained so, and
constraint violations arising from data corruption went undetected.
Back-patch to 9.0, like the causative commit.
Tom Lane [Mon, 29 Jul 2013 14:42:37 +0000 (10:42 -0400)]
Fix contrib/cube and contrib/seg to build with bison 3.0.
These modules used the YYPARSE_PARAM macro, which has been deprecated
by the bison folk since 1.875, and which they finally removed in 3.0.
Adjust the code to use the replacement facility, %parse-param, which
is a much better solution anyway since it allows specification of the
type of the extra parser parameter. We can thus get rid of a lot of
unsightly casting.
Back-patch to all active branches, since somebody might try to build
a back branch with up-to-date tools.
Bruce Momjian [Sat, 27 Jul 2013 19:00:58 +0000 (15:00 -0400)]
pg_upgrade: fix -j race condition on Windows
Pg_Upgrade cannot write the command string to the log file and then call
system() to write to the same file without causing occasional file-share
errors on Windows. So instead, write the command string to the log file
after system(), in those cases.
Backpatch to 9.3.
Bruce Momjian [Fri, 26 Jul 2013 17:52:01 +0000 (13:52 -0400)]
pg_upgrade docs: don't use cluster for binary/lib
In a few cases, pg_upgrade said old/new cluster location when it meant
old/new Postgres install location, so fix those.
Per private email report
Tom Lane [Thu, 25 Jul 2013 20:45:43 +0000 (16:45 -0400)]
Prevent leakage of SPI tuple tables during subtransaction abort.
plpgsql often just remembers SPI-result tuple tables in local variables,
and has no mechanism for freeing them if an ereport(ERROR) causes an escape
out of the execution function whose local variable it is. In the original
coding, that wasn't a problem because the tuple table would be cleaned up
when the function's SPI context went away during transaction abort.
However, once plpgsql grew the ability to trap exceptions, repeated
trapping of errors within a function could result in significant
intra-function-call memory leakage, as illustrated in bug #8279 from
Chad Wagner.
We could fix this locally in plpgsql with a bunch of PG_TRY/PG_CATCH
coding, but that would be tedious, probably slow, and prone to bugs of
omission; moreover it would do nothing for similar risks elsewhere.
What seems like a better plan is to make SPI itself responsible for
freeing tuple tables at subtransaction abort. This patch attacks the
problem that way, keeping a list of live tuple tables within each SPI
function context. Currently, such freeing is automatic for tuple tables
made within the failed subtransaction. We might later add a SPI call to
mark a tuple table as not to be freed this way, allowing callers to opt
out; but until someone exhibits a clear use-case for such behavior, it
doesn't seem worth bothering.
A very useful side-effect of this change is that SPI_freetuptable() can
now defend itself against bad calls, such as duplicate free requests;
this should make things more robust in many places. (In particular,
this reduces the risks involved if a third-party extension contains
now-redundant SPI_freetuptable() calls in error cleanup code.)
Even though the leakage problem is of long standing, it seems imprudent
to back-patch this into stable branches, since it does represent an API
semantics change for SPI users. We'll patch this in 9.3, but live with
the leakage in older branches.
Robert Haas [Thu, 25 Jul 2013 20:36:49 +0000 (16:36 -0400)]
pgstattuple: Doc update for previous commit.
In my previous change to make pgstattuple use SnapshotDirty rather
than SnapshotNow, I failed to notice that the documenation also
needed to be updated to match. Fix.
Robert Haas [Thu, 25 Jul 2013 20:32:02 +0000 (16:32 -0400)]
Change currtid functions to use an MVCC snapshot, not SnapshotNow.
This has a slight performance cost, but the only known consumers
of these functions, known at the SQL level as currtid and currtid2,
is pgsql-odbc; whose usage, we hope, is not sufficiently intensive
to make this a problem.
Robert Haas [Thu, 25 Jul 2013 20:16:42 +0000 (16:16 -0400)]
pgstattuple: Use SnapshotDirty, not SnapshotNow.
Tuples belonging to uncommitted transactions should not be
counted as dead.
This is arguably a bug fix that should be back-patched, but
as no one ever noticed until it came time to try to get rid
of SnapshotNow, I'm only doing this in master for now.
Tom Lane [Thu, 25 Jul 2013 15:39:08 +0000 (11:39 -0400)]
Fix configure probe for sys/ucred.h.
The configure script's test for <sys/ucred.h> did not work on OpenBSD,
because on that platform <sys/param.h> has to be included first.
As a result, socket peer authentication was disabled on that platform.
Problem introduced in commit be4585b1c27ac5dbdd0d61740d18f7ad9a00e268.
Bruce Momjian [Thu, 25 Jul 2013 15:33:15 +0000 (11:33 -0400)]
pg_upgrade: adjust umask() calls
Since pg_upgrade -j on Windows uses threads, calling umask()
before/after opening a file via fopen_priv() is no longer possible, so
set umask() as we enter the thread-creating loop, and reset it on exit.
Also adjust internal fopen_priv() calls to just use fopen().
Backpatch to 9.3beta.
Stephen Frost [Thu, 25 Jul 2013 13:41:55 +0000 (09:41 -0400)]
Improvements to GetErrorContextStack()
As GetErrorContextStack() borrowed setup and tear-down code from other
places, it was less than clear that it must only be called as a
top-level entry point into the error system and can't be called by an
exception handler (unlike the rest of the error system, which is set up
to be reentrant-safe).
Being called from an exception handler is outside the charter of
GetErrorContextStack(), so add a bit more protection against it,
improve the comments addressing why we have to set up an errordata
stack for this function at all, and add a few more regression tests.
Lack of clarity pointed out by Tom Lane; all bugs are mine.
Bruce Momjian [Thu, 25 Jul 2013 02:01:14 +0000 (22:01 -0400)]
pg_upgrade: fix initialization of thread argument
Reorder initialization of thread argument marker to it happens before
reap_child() is called.
Backpatch to 9.3.
Stephen Frost [Wed, 24 Jul 2013 22:53:27 +0000 (18:53 -0400)]
Add GET DIAGNOSTICS ... PG_CONTEXT in PL/PgSQL
This adds the ability to get the call stack as a string from within a
PL/PgSQL function, which can be handy for logging to a table, or to
include in a useful message to an end-user.
Pavel Stehule, reviewed by Rushabh Lathia and rather heavily whacked
around by Stephen Frost.
Tom Lane [Wed, 24 Jul 2013 21:41:55 +0000 (17:41 -0400)]
Improve ilist.h's support for deletion of slist elements during iteration.
Previously one had to use slist_delete(), implying an additional scan of
the list, making this infrastructure considerably less efficient than
traditional Lists when deletion of element(s) in a long list is needed.
Modify the slist_foreach_modify() macro to support deleting the current
element in O(1) time, by keeping a "prev" pointer in addition to "cur"
and "next". Although this makes iteration with this macro a bit slower,
no real harm is done, since in any scenario where you're not going to
delete the current list element you might as well just use slist_foreach
instead. Improve the comments about when to use each macro.
Back-patch to 9.3 so that we'll have consistent semantics in all branches
that provide ilist.h. Note this is an ABI break for callers of
slist_foreach_modify().