Commit Graph

15451 Commits

Author SHA1 Message Date
Robert Haas b648b70342 Speed up CREATE INDEX CONCURRENTLY's TID sort.
Encode TIDs as 64-bit integers to speed up comparisons.  This seems to
speed things up on all platforms, but is even more beneficial when
8-byte integers are passed by value.

Peter Geoghegan.  Design suggestions and review by Tom Lane.  Review
also by Simon Riggs and by me.
2015-12-16 15:23:45 -05:00
Robert Haas f27a6b15e6 Mark CHECK constraints declared NOT VALID valid if created with table.
FOREIGN KEY constraints have behaved this way for a long time, but for
some reason the behavior of CHECK constraints has been inconsistent up
until now.

Amit Langote and Amul Sul, with assorted tweaks by me.
2015-12-16 07:43:56 -05:00
Robert Haas 049469e7e7 Teach mdnblocks() not to create zero-length files.
It's entirely surprising that mdnblocks() has the side effect of
creating new files on disk, so let's make it not do that.  One
consequence of the old behavior is that, if running on a damaged
cluster that is missing a file, mdnblocks() can recreate the file
and allow a subsequent _mdfd_getseg() for a higher segment to succeed.
This happens because, while mdnblocks() stops when it finds a segment
that is shorter than 1GB, _mdfd_getseg() has no such check, and thus
the empty file created by mdnblocks() can allow it to continue its
traversal and find higher-numbered segments which remain.

It might be a good idea for _mdfd_getseg() to actually verify that
each segment it finds is exactly 1GB before proceeding to the next
one, but that would involve some additional system calls, so for
now I'm just doing this much.

Patch by me, per off-list analysis by Kevin Grittner and Rahila Syed.
Review by Andres Freund.
2015-12-15 13:57:45 -05:00
Robert Haas 6150a1b08a Move buffer I/O and content LWLocks out of the main tranche.
Move the content lock directly into the BufferDesc, so that locking and
pinning a buffer touches only one cache line rather than two.  Adjust
the definition of BufferDesc slightly so that this doesn't make the
BufferDesc any larger than one cache line (at least on platforms where
a spinlock is only 1 or 2 bytes).

We can't fit the I/O locks into the BufferDesc and stay within one
cache line, so move those to a completely separate tranche.  This
leaves a relatively limited number of LWLocks in the main tranche, so
increase the padding of those remaining locks to a full cache line,
rather than allowing adjacent locks to share a cache line, hopefully
reducing false sharing.

Performance testing shows that these changes make little difference
on laptop-class machines, but help significantly on larger servers,
especially those with more than 2 sockets.

Andres Freund, originally based on an earlier patch by Simon Riggs.
Review and cosmetic adjustments (including heavy rewriting of the
comments) by me.
2015-12-15 13:32:54 -05:00
Robert Haas 3fed417452 Provide a way to predefine LWLock tranche IDs.
It's a bit cumbersome to use LWLockNewTrancheId(), because the returned
value needs to be shared between backends so that each backend can call
LWLockRegisterTranche() with the correct ID.  So, for built-in tranches,
use a hard-coded value instead.

This is motivated by an upcoming patch adding further built-in tranches.

Andres Freund and Robert Haas
2015-12-15 11:48:19 -05:00
Stephen Frost e5e11c8cca Collect the global OR of hasRowSecurity flags for plancache
We carry around information about if a given query has row security or
not to allow the plancache to use that information to invalidate a
planned query in the event that the environment changes.

Previously, the flag of one of the subqueries was simply being copied
into place to indicate if the query overall included RLS components.
That's wrong as we need the global OR of all subqueries.  Fix by
changing the code to match how fireRIRules works, which is results
in OR'ing all of the flags.

Noted by Tom.

Back-patch to 9.5 where RLS was introduced.
2015-12-14 20:05:43 -05:00
Alvaro Herrera 0d8f3d5d11 Add missing CHECK_FOR_INTERRUPTS in lseg_inside_poly
Apparently, there are bugs in this code that cause it to loop endlessly.
That bug still needs more research, but in the meantime it's clear that
the loop is missing a check for interrupts so that it can be cancelled
timely.

Backpatch to 9.1 -- this has been missing since 49475aab8d.
2015-12-14 16:44:40 -03:00
Andres Freund cca705a5d9 Fix bug in SetOffsetVacuumLimit() triggered by find_multixact_start() failure.
Previously, if find_multixact_start() failed, SetOffsetVacuumLimit() would
install 0 into MultiXactState->offsetStopLimit if it previously succeeded.
Luckily, there are no known cases where find_multixact_start() will return
an error in 9.5 and above. But if it were to happen, for example due to
filesystem permission issues, it'd be somewhat bad: GetNewMultiXactId()
could continue allocating mxids even if close to a wraparound, or it could
erroneously stop allocating mxids, even if no wraparound is looming.  The
wrong value would be corrected the next time SetOffsetVacuumLimit() is
called, or by a restart.

Reported-By: Noah Misch, although this is not his preferred fix
Discussion: 20151210140450.GA22278@alap3.anarazel.de
Backpatch: 9.5, where the bug was introduced as part of 4f627f
2015-12-14 11:34:16 +01:00
Andres Freund 2a3544960e Correct statement to actually be the intended assert statement.
e3f4cfc7 introduced a LWLockHeldByMe() call, without the corresponding
Assert() surrounding it.

Spotted by Coverity.

Backpatch: 9.1+, like the previous commit
2015-12-14 11:23:24 +01:00
Magnus Hagander a91bdf67c4 Consistently set all fields in pg_stat_replication to null instead of 0
Previously the "sent" field would be set to 0 and all other xlog
pointers be set to NULL if there were no valid values (such as when
in a backup sending walsender).
2015-12-13 16:53:38 +01:00
Magnus Hagander 263c19572b Properly initialize write, flush and replay locations in walsender slots
These would leak random xlog positions if a walsender used for backup would
a walsender slot previously used by a replication walsender.

In passing also fix a couple of cases where the xlog pointer is directly
compared to zero instead of using XLogRecPtrIsInvalid, noted by
Michael Paquier.
2015-12-13 16:46:56 +01:00
Andres Freund f54d0629ec Fix ALTER TABLE ... SET TABLESPACE for unlogged relations.
Changing the tablespace of an unlogged relation did not WAL log the
creation and content of the init fork. Thus, after a standby is
promoted, unlogged relation cannot be accessed anymore, with errors
like:
ERROR:  58P01: could not open file "pg_tblspc/...": No such file or directory
Additionally the init fork was not synced to disk, independent of the
configured wal_level, a relatively small durability risk.

Investigation of that problem also brought to light that, even for
permanent relations, the creation of !main forks was not WAL logged,
i.e. no XLOG_SMGR_CREATE record were emitted. That mostly turns out not
to be a problem, because these files were created when the actual
relation data is copied; nonexistent files are not treated as an error
condition during replay. But that doesn't work for empty files, and
generally feels a bit haphazard. Luckily, outside init and main forks,
empty forks don't occur often or are not a problem.

Add the required WAL logging and syncing to disk.

Reported-By: Michael Paquier
Author: Michael Paquier and Andres Freund
Discussion: 20151210163230.GA11331@alap3.anarazel.de
Backpatch: 9.1, where unlogged relations were introduced
2015-12-12 14:17:39 +01:00
Alvaro Herrera 8c1615531f For REASSIGN OWNED for foreign user mappings
As reported in bug #13809 by Alexander Ashurkov, the code for REASSIGN
OWNED hadn't gotten word about user mappings.  Deal with them in the
same way default ACLs do, which is to ignore them altogether; they are
handled just fine by DROP OWNED.  The other foreign object cases are
already handled correctly by both commands.

Also add a REASSIGN OWNED statement to foreign_data test to exercise the
foreign data objects.  (The changes are just before the "cleanup" phase,
so it shouldn't remove any existing live test.)

Reported by Alexander Ashurkov, then independently by Jaime Casanova.
2015-12-11 18:39:09 -03:00
Stephen Frost 833728d4c8 Handle policies during DROP OWNED BY
DROP OWNED BY handled GRANT-based ACLs but was not removing roles from
policies.  Fix that by having DROP OWNED BY remove the role specified
from the list of roles the policy (or policies) apply to, or the entire
policy (or policies) if it only applied to the role specified.

As with ACLs, the DROP OWNED BY caller must have permission to modify
the policy or a WARNING is thrown and no change is made to the policy.
2015-12-11 16:12:25 -05:00
Tom Lane 4fcf48450d Get rid of the planner's LateralJoinInfo data structure.
I originally modeled this data structure on SpecialJoinInfo, but after
commit acfcd45cac that looks like a pretty poor decision.
All we really need is relid sets identifying laterally-referenced rels;
and most of the time, what we want to know about includes indirect lateral
references, a case the LateralJoinInfo data was unsuited to compute with
any efficiency.  The previous commit redefined RelOptInfo.lateral_relids
as the transitive closure of lateral references, so that it easily supports
checking indirect references.  For the places where we really do want just
direct references, add a new RelOptInfo field direct_lateral_relids, which
is easily set up as a copy of lateral_relids before we perform the
transitive closure calculation.  Then we can just drop lateral_info_list
and LateralJoinInfo and the supporting code.  This makes the planner's
handling of lateral references noticeably more efficient, and shorter too.

Such a change can't be back-patched into stable branches for fear of
breaking extensions that might be looking at the planner's data structures;
but it seems not too late to push it into 9.5, so I've done so.
2015-12-11 15:52:38 -05:00
Stephen Frost ed8bec915e Handle dependencies properly in ALTER POLICY
ALTER POLICY hadn't fully considered partial policy alternation
(eg: change just the roles on the policy, or just change one of
the expressions) when rebuilding the dependencies.  Instead, it
would happily remove all dependencies which existed for the
policy and then only recreate the dependencies for the objects
referred to in the specific ALTER POLICY command.

Correct that by extracting and building the dependencies for all
objects referenced by the policy, regardless of if they were
provided as part of the ALTER POLICY command or were already in
place as part of the pre-existing policy.
2015-12-11 15:43:03 -05:00
Tom Lane acfcd45cac Still more fixes for planner's handling of LATERAL references.
More fuzz testing by Andreas Seltenreich exposed that the planner did not
cope well with chains of lateral references.  If relation X references Y
laterally, and Y references Z laterally, then we will have to scan X on the
inside of a nestloop with Z, so for all intents and purposes X is laterally
dependent on Z too.  The planner did not understand this and would generate
intermediate joins that could not be used.  While that was usually harmless
except for wasting some planning cycles, under the right circumstances it
would lead to "failed to build any N-way joins" or "could not devise a
query plan" planner failures.

To fix that, convert the existing per-relation lateral_relids and
lateral_referencers relid sets into their transitive closures; that is,
they now show all relations on which a rel is directly or indirectly
laterally dependent.  This not only fixes the chained-reference problem
but allows some of the relevant tests to be made substantially simpler
and faster, since they can be reduced to simple bitmap manipulations
instead of searches of the LateralJoinInfo list.

Also, when a PlaceHolderVar that is due to be evaluated at a join contains
lateral references, we should treat those references as indirect lateral
dependencies of each of the join's base relations.  This prevents us from
trying to join any individual base relations to the lateral reference
source before the join is formed, which again cannot work.

Andreas' testing also exposed another oversight in the "dangerous
PlaceHolderVar" test added in commit 85e5e222b1.  Simply rejecting
unsafe join paths in joinpath.c is insufficient, because in some cases
we will end up rejecting *all* possible paths for a particular join, again
leading to "could not devise a query plan" failures.  The restriction has
to be known also to join_is_legal and its cohort functions, so that they
will not select a join for which that will happen.  I chose to move the
supporting logic into joinrels.c where the latter functions are.

Back-patch to 9.3 where LATERAL support was introduced.
2015-12-11 14:22:20 -05:00
Alvaro Herrera 69e7235c93 Fix commit timestamp initialization
This module needs explicit initialization in order to replay WAL records
in recovery, but we had broken this recently following changes to make
other (stranger) scenarios work correctly.  To fix, rework the
initialization sequence so that it always takes place before WAL replay
commences for both master and standby.

I could have gone for a more localized fix that just added a "startup"
call for the master server, but it seemed better to restructure the
existing callers as well so that the whole thing made more sense.  As a
drawback, there is more control logic in xlog.c now than previously, but
doing otherwise meant passing down the ControlFile flag, which seemed
uglier as a whole.

This also meant adding a check to not re-execute ActivateCommitTs if it
had already been called.

Reported by Fujii Masao.

Backpatch to 9.5.
2015-12-11 14:30:43 -03:00
Peter Eisentraut a351705d8a Improve some messages 2015-12-10 22:05:27 -05:00
Andres Freund 84ac126ee7 Fix ON CONFLICT UPDATE bug breaking AFTER UPDATE triggers.
ExecOnConflictUpdate() passed t_ctid of the to-be-updated tuple to
ExecUpdate(). That's problematic primarily because of two reason: First
and foremost t_ctid could point to a different tuple. Secondly, and
that's what triggered the complaint by Stanislav, t_ctid is changed by
heap_update() to point to the new tuple version.  The behavior of AFTER
UPDATE triggers was therefore broken, with NEW.* and OLD.* tuples
spuriously identical within AFTER UPDATE triggers.

To fix both issues, pass a pointer to t_self of a on-stack HeapTuple
instead.

Fixing this bug lead to one change in regression tests, which previously
failed due to the first issue mentioned above. There's a reasonable
expectation that test fails, as it updates one row repeatedly within one
INSERT ... ON CONFLICT statement. That is only possible if the second
update is triggered via ON CONFLICT ... SET, ON CONFLICT ... WHERE, or
by a WITH CHECK expression, as those are executed after
ExecOnConflictUpdate() does a visibility check. That could easily be
prohibited, but given it's allowed for plain UPDATEs and a rare corner
case, it doesn't seem worthwhile.

Reported-By: Stanislav Grozev
Author: Andres Freund and Peter Geoghegan
Discussion: CAA78GVqy1+LisN-8DygekD_Ldfy=BJLarSpjGhytOsgkpMavfQ@mail.gmail.com
Backpatch: 9.5, where ON CONFLICT was introduced
2015-12-10 16:29:26 +01:00
Andres Freund e3f4cfc7aa Fix bug leading to restoring unlogged relations from empty files.
At the end of crash recovery, unlogged relations are reset to the empty
state, using their init fork as the template. The init fork is copied to
the main fork without going through shared buffers. Unfortunately WAL
replay so far has not necessarily flushed writes from shared buffers to
disk at that point. In normal crash recovery, and before the
introduction of 'fast promotions' in fd4ced523 / 9.3, the
END_OF_RECOVERY checkpoint flushes the buffers out in time. But with
fast promotions that's not the case anymore.

To fix, force WAL writes targeting the init fork to be flushed
immediately (using the new FlushOneBuffer() function). In 9.5+ that
flush can centrally be triggered from the code dealing with restoring
full page writes (XLogReadBufferForRedoExtended), in earlier releases
that responsibility is in the hands of XLOG_HEAP_NEWPAGE's replay
function.

Backpatch to 9.1, even if this currently is only known to trigger in
9.3+. Flushing earlier is more robust, and it is advantageous to keep
the branches similar.

Typical symptoms of this bug are errors like
'ERROR:  index "..." contains unexpected zero page at block 0'
shortly after promoting a node.

Reported-By: Thom Brown
Author: Andres Freund and Michael Paquier
Discussion: 20150326175024.GJ451@alap3.anarazel.de
Backpatch: 9.1-
2015-12-10 16:29:26 +01:00
Robert Haas b287df70e4 Allow EXPLAIN (ANALYZE, VERBOSE) to display per-worker statistics.
The original parallel sequential scan commit included only very limited
changes to the EXPLAIN output.  Aggregated totals from all workers were
displayed, but there was no way to see what each individual worker did
or to distinguish the effort made by the workers from the effort made by
the leader.

Per a gripe by Thom Brown (and maybe others).  Patch by me, reviewed
by Amit Kapila.
2015-12-09 13:21:19 -05:00
Kevin Grittner 25c5392330 Improve performance in freeing memory contexts
The single linked list of memory contexts could result in O(N^2)
performance to free a set of contexts if they were not freed in
reverse order of creation.  In many cases the reverse order was
used, but there were some significant exceptions that caused real-
world performance problems.  Rather than requiring all callers to
care about the order in which contexts were freed, and hunting down
and changing all existing cases where the wrong order was used, we
add one pointer per memory context so that the implementation
details are not so visible.

Jan Wieck
2015-12-08 17:32:49 -06:00
Robert Haas 385f337c9f Allow foreign and custom joins to handle EvalPlanQual rechecks.
Commit e7cb7ee145 provided basic
infrastructure for allowing a foreign data wrapper or custom scan
provider to replace a join of one or more tables with a scan.
However, this infrastructure failed to take into account the need
for possible EvalPlanQual rechecks, and ExecScanFetch would fail
an assertion (or just overwrite memory) if such a check was attempted
for a plan containing a pushed-down join.  To fix, adjust the EPQ
machinery to skip some processing steps when scanrelid == 0, making
those the responsibility of scan's recheck method, which also has
the responsibility in this case of correctly populating the relevant
slot.

To allow foreign scans to gain control in the right place to make
use of this new facility, add a new, optional RecheckForeignScan
method.  Also, allow a foreign scan to have a child plan, which can
be used to correctly populate the slot (or perhaps for something
else, but this is the only use currently envisioned).

KaiGai Kohei, reviewed by Robert Haas, Etsuro Fujita, and Kyotaro
Horiguchi.
2015-12-08 12:31:03 -05:00
Tom Lane edca44b152 Simplify LATERAL-related calculations within add_paths_to_joinrel().
While convincing myself that commit 7e19db0c09 would solve both of
the problems recently reported by Andreas Seltenreich, I realized that
add_paths_to_joinrel's handling of LATERAL restrictions could be made
noticeably simpler and faster if we were to retain the minimum possible
parameterization for each joinrel (that is, the set of relids supplying
unsatisfied lateral references in it).  We already retain that for
baserels, in RelOptInfo.lateral_relids, so we can use that field for
joinrels too.

I re-pgindent'd the files touched here, which affects some unrelated
comments.

This is, I believe, just a minor optimization not a bug fix, so no
back-patch.
2015-12-07 18:56:17 -05:00
Tom Lane 7e19db0c09 Fix another oversight in checking if a join with LATERAL refs is legal.
It was possible for the planner to decide to join a LATERAL subquery to
the outer side of an outer join before the outer join itself is completed.
Normally that's fine because of the associativity rules, but it doesn't
work if the subquery contains a lateral reference to the inner side of the
outer join.  In such a situation the outer join *must* be done first.
join_is_legal() missed this consideration and would allow the join to be
attempted, but the actual path-building code correctly decided that no
valid join path could be made, sometimes leading to planner errors such as
"failed to build any N-way joins".

Per report from Andreas Seltenreich.  Back-patch to 9.3 where LATERAL
support was added.
2015-12-07 17:42:11 -05:00
Alvaro Herrera 820ddb2c2f Further tweak commit_timestamp behavior
As pointed out by Fujii Masao, we weren't quite there on a standby
behaving sanely: first because we were failing to acquire the correct
state in the case where no XLOG_PARAMETER_CHANGE message was sent
(because a checkpoint had already happened after the setting was changed
in the master, and then the standby was restarted); and second because
promoting the standby with the feature enabled failed to activate it if
the master had the feature disabled.

This patch fixes both those misbehaviors hopefully without
re-introducing any old problems.

Also change the hint emitted in a standby together with the error
message about the feature being disabled, to make it point out that the
place to chance the setting is the master.  Otherwise, if the setting is
already enabled in the standby, it is very confusing to have it say that
the setting must be enabled ...

Authors: Álvaro Herrera, Petr Jelínek.
Backpatch to 9.5.
2015-12-03 19:22:31 -03:00
Robert Haas c7485a82c3 Add handling for GatherPath to print_path.
Peter Geoghegan
2015-12-02 08:19:50 -05:00
Tom Lane 7fb008c5ee Make gincostestimate() cope with hypothetical GIN indexes.
We tried to fetch statistics data from the index metapage, which does not
work if the index isn't actually present.  If the index is hypothetical,
instead extrapolate some plausible internal statistics based on the index
page count provided by the index-advisor plugin.

There was already some code in gincostestimate() to invent internal stats
in this way, but since it was only meant as a stopgap for pre-9.1 GIN
indexes that hadn't been vacuumed since upgrading, it was pretty crude.
If we want it to support index advisors, we should try a little harder.
A small amount of testing says that it's better to estimate the entry pages
as 90% of the index, not 100%.  Also, estimating the number of entries
(keys) as equal to the heap tuple count could be wildly wrong in either
direction.  Instead, let's estimate 100 entries per entry page.

Perhaps someday somebody will want the index advisor to be able to provide
these numbers more directly, but for the moment this should serve.

Problem report and initial patch by Julien Rouhaud; modified by me to
invent less-bogus internal statistics.  Back-patch to all supported
branches, since we've supported index advisors since 9.0.
2015-12-01 16:24:34 -05:00
Robert Haas 3690dc6b03 Fix obsolete comment.
It's amazing how fast things become obsolete these days.

Amit Langote
2015-11-30 12:54:46 -05:00
Tom Lane ec7eef6b11 Avoid caching expression state trees for domain constraints across queries.
In commit 8abb3cda0d I attempted to cache
the expression state trees constructed for domain CHECK constraints for
the life of the backend (assuming the domain's constraints don't get
redefined).  However, this turns out not to work very well, because
execQual.c will run those state trees with ecxt_per_query_memory pointing
to a query-lifespan context, and in some situations we'll end up with
pointers into that context getting stored into the state trees.  This
happens in particular with SQL-language functions, as reported by
Emre Hasegeli, but there are many other cases.

To fix, keep only the expression plan trees for domain CHECK constraints
in the typcache's data structure, and revert to performing ExecInitExpr
(at least) once per query to set up expression state trees in the query's
context.

Eventually it'd be nice to undo this, but that will require some careful
thought about memory management for expression state trees, and it seems
far too late for any such redesign in 9.5.  This way is still much more
efficient than what happened before 8abb3cda0.
2015-11-29 18:18:42 -05:00
Tom Lane 8d32717b6b Avoid doing encoding conversions by double-conversion via MULE_INTERNAL.
Previously, we did many conversions for Cyrillic and Central European
single-byte encodings by converting to a related MULE_INTERNAL coding
scheme before converting to the destination.  This seems unnecessarily
inefficient.  Moreover, if the conversion encounters an untranslatable
character, the error message will confusingly complain about failure
to convert to or from MULE_INTERNAL, rather than the user-visible
encodings.  Worse still, this approach results in some completely
unnecessary conversion failures; there are cases where the chosen
MULE subset lacks characters that exist in both of the user-visible
encodings, causing a conversion failure that need not occur.

This patch fixes the first two of those deficiencies by introducing
a new local2local() conversion support subroutine for direct conversion
between any two single-byte character sets, and adding new conversion
tables where needed.  However, I generated the new conversion tables by
testing PG 9.5's behavior, so that the actual conversion behavior is
bug-compatible with previous releases; the only user-visible behavior
change is that the error messages for conversion failures are saner.
Changes in the conversion behavior will probably ensue after discussion.

Interestingly, although this approach requires more tables, the .so files
actually end up smaller (at least on my x86_64 machine); the tables are
smaller than the management code needed for double conversion.

Per a complaint from Albe Laurenz.
2015-11-28 13:42:27 -05:00
Tom Lane 5afdfc9cbb Update UCS_to_GB18030.pl with info about origin of the reference file. 2015-11-27 17:31:26 -05:00
Tom Lane e17dab53ea Auto-generate file header comments in Unicode mapping files.
Some of the Unicode/*.map files had identification comments added to them,
evidently by hand.  Others did not.  Modify the generating scripts to
produce these comments automatically, and update the generated files that
lacked them.

This is just minor cleanup as a by-product of trying to verify that the
*.map files can indeed be reproduced from authoritative data.  There are a
depressingly large number that fail to reproduce from the claimed sources.
I have not touched those in this commit, except for the JIS 2004-related
files which required only a single comment update to match.

Since this only affects comments, no need to consider a back-patch.
2015-11-27 16:50:47 -05:00
Teodor Sigaev 92e38182d7 COPY (INSERT/UPDATE/DELETE .. RETURNING ..)
Attached is a patch for being able to do COPY (query) without a CTE.

Author: Marko Tiikkaja
Review: Michael Paquier
2015-11-27 19:11:22 +03:00
Tom Lane 0da3a9bef7 Fix failure to consider failure cases in GetComboCommandId().
Failure to initially palloc the comboCids array, or to realloc it bigger
when needed, left combocid's data structures in an inconsistent state that
would cause trouble if the top transaction continues to execute.  Noted
while examining a user complaint about the amount of memory used for this.
(There's not much we can do about that, but it does point up that repalloc
failure has a non-negligible chance of occurring here.)

In HEAD/9.5, also avoid possible invocation of memcpy() with a null pointer
in SerializeComboCIDState; cf commit 13bba0227.
2015-11-26 13:23:02 -05:00
Tom Lane 46166197c3 Improve div_var_fast(), mostly by making comments better.
The integer overflow situation in div_var_fast() is a great deal more
complicated than the pre-existing comments would suggest.  Moreover, the
comments were also flat out incorrect as to the precise statement of the
maxdiv loop invariant.  Upon clarifying that, it becomes apparent that the
way in which we updated maxdiv after a carry propagation pass was overly
slow, complex, and conservative: we can just reset it to one, which is much
easier and also reduces the number of times carry propagation occurs.
Fix that and improve the relevant comments.

Since this is mostly a comment fix, with only a rather marginal performance
boost, no need for back-patch.

Tom Lane and Dean Rasheed
2015-11-25 16:05:57 -05:00
Tom Lane 00cdd83521 Adopt the GNU convention for handling tar-archive members exceeding 8GB.
The POSIX standard for tar headers requires archive member sizes to be
printed in octal with at most 11 digits, limiting the representable file
size to 8GB.  However, GNU tar and apparently most other modern tars
support a convention in which oversized values can be stored in base-256,
allowing any practical file to be a tar member.  Adopt this convention
to remove two limitations:
* pg_dump with -Ft output format failed if the contents of any one table
exceeded 8GB.
* pg_basebackup failed if the data directory contained any file exceeding
8GB.  (This would be a fatal problem for installations configured with a
table segment size of 8GB or more, and it has also been seen to fail when
large core dump files exist in the data directory.)

File sizes under 8GB are still printed in octal, so that no compatibility
issues are created except in cases that would have failed entirely before.

In addition, this patch fixes several bugs in the same area:

* In 9.3 and later, we'd defined tarCreateHeader's file-size argument as
size_t, which meant that on 32-bit machines it would write a corrupt tar
header for file sizes between 4GB and 8GB, even though no error was raised.
This broke both "pg_dump -Ft" and pg_basebackup for such cases.

* pg_restore from a tar archive would fail on tables of size between 4GB
and 8GB, on machines where either "size_t" or "unsigned long" is 32 bits.
This happened even with an archive file not affected by the previous bug.

* pg_basebackup would fail if there were files of size between 4GB and 8GB,
even on 64-bit machines.

* In 9.3 and later, "pg_basebackup -Ft" failed entirely, for any file size,
on 64-bit big-endian machines.

In view of these potential data-loss bugs, back-patch to all supported
branches, even though removal of the documented 8GB limit might otherwise
be considered a new feature rather than a bug fix.
2015-11-21 20:21:31 -05:00
Tom Lane 074c5cfbfb Fix handling of inherited check constraints in ALTER COLUMN TYPE (again).
The previous way of reconstructing check constraints was to do a separate
"ALTER TABLE ONLY tab ADD CONSTRAINT" for each table in an inheritance
hierarchy.  However, that way has no hope of reconstructing the check
constraints' own inheritance properties correctly, as pointed out in
bug #13779 from Jan Dirk Zijlstra.  What we should do instead is to do
a regular "ALTER TABLE", allowing recursion, at the topmost table that
has a particular constraint, and then suppress the work queue entries
for inherited instances of the constraint.

Annoyingly, we'd tried to fix this behavior before, in commit 5ed6546cf,
but we failed to notice that it wasn't reconstructing the pg_constraint
field values correctly.

As long as I'm touching pg_get_constraintdef_worker anyway, tweak it to
always schema-qualify the target table name; this seems like useful backup
to the protections installed by commit 5f173040.

In HEAD/9.5, get rid of get_constraint_relation_oids, which is now unused.
(I could alternatively have modified it to also return conislocal, but that
seemed like a pretty single-purpose API, so let's not pretend it has some
other use.)  It's unused in the back branches as well, but I left it in
place just in case some third-party code has decided to use it.

In HEAD/9.5, also rename pg_get_constraintdef_string to
pg_get_constraintdef_command, as the previous name did nothing to explain
what that entry point did differently from others (and its comment was
equally useless).  Again, that change doesn't seem like material for
back-patching.

I did a bit of re-pgindenting in tablecmds.c in HEAD/9.5, as well.

Otherwise, back-patch to all supported branches.
2015-11-20 14:55:47 -05:00
Robert Haas 6c878a7553 Avoid server crash when worker registration fails at execution time.
The previous coding attempts to destroy the DSM in this case, but
child nodes might have stored data there and still be holding onto
pointers in this case.  So don't do that.

Also, free the reader array instead of leaking it.

Extracted from two different patch versions both by Amit Kapila.
2015-11-20 13:03:39 -05:00
Robert Haas 74d0d5f3eb Fix typo in comment.
Amit Langote
2015-11-19 16:45:39 -05:00
Robert Haas fea2b642fd Remove numbers from incorrectly-numbered list.
Reported by Andres Freund.
2015-11-19 16:45:13 -05:00
Robert Haas bc4996e61b Make ALTER .. SET SCHEMA do nothing, instead of throwing an ERROR.
This was already true for CREATE EXTENSION, but historically has not
been true for other object types.  Therefore, this is a backward
incompatibility.  Per discussion on pgsql-hackers, everyone seems to
agree that the new behavior is better.

Marti Raudsepp, reviewed by Haribabu Kommi and myself
2015-11-19 10:49:25 -05:00
Robert Haas 7907a949ab Fix incomplete set_foreignscan_references handling for fdw_recheck_quals
KaiGai Kohei
2015-11-18 22:12:21 -05:00
Andres Freund d3c8ac114f Remove function names from some elog() calls in heapam.c.
At least one of the names was, due to a function renaming late in the
development of ON CONFLICT, wrong. Since including function names in
error messages is against the message style guide anyway, remove them
from the messages.

Discussion: CAM3SWZT8paz=usgMVHm0XOETkQvzjRtAUthATnmaHQQY0obnGw@mail.gmail.com
Backpatch: 9.5, where ON CONFLICT was introduced
2015-11-19 01:37:58 +01:00
Robert Haas 166b61a88e Avoid aggregating worker instrumentation multiple times.
Amit Kapila, per design ideas from me.
2015-11-18 12:35:25 -05:00
Robert Haas adeee97486 Fix dumb bug in tqueue.c
When I wrote this code originally, the intention was to recompute the
remapinfo only when the tupledesc changes.  This presumably only
happens once per query, but I copied the design pattern from other
DestReceivers.  However, due to a silly oversight on my part,
tqueue->tupledesc never got set, leading to recomputation for every
tuple.

This should improve the performance of parallel scans that return a
significant number of tuples.

Report by Amit Kapila; patch by me, reviewed by him.
2015-11-18 08:25:33 -05:00
Tom Lane 5f10b7a604 Fix possible internal overflow in numeric division.
div_var_fast() postpones propagating carries in the same way as mul_var(),
so it has the same corner-case overflow risk we fixed in 246693e5ae,
namely that the size of the carries has to be accounted for when setting
the threshold for executing a carry propagation step.  We've not devised
a test case illustrating the brokenness, but the required fix seems clear
enough.  Like the previous fix, back-patch to all active branches.

Dean Rasheed
2015-11-17 15:46:47 -05:00
Peter Eisentraut c5ec406412 Message style fix
from Euler Taveira
2015-11-17 06:53:07 -05:00
Peter Eisentraut 5db837d3f2 Message improvements 2015-11-16 21:39:23 -05:00