set to the large object context ("fscxt"), as this is inevitably a source of
transaction-duration memory leaks. Not sure why we'd not noticed it before;
maybe people weren't touching a whole lot of LOs in the same transaction
before the 8.1 pg_dump changes. Per report from Wayne Conrad.
Backpatched as far as 8.1, but the problem doubtless goes all the way back.
I'm disinclined to spend the time to try to verify that the older branches
would still work if patched, seeing that this code was significantly modified
for 8.0 and again for 8.1, and that we don't have any trouble reports before
8.1. (Maybe the leaks were smaller before?)
thereby saving a visit to the metapage in most index searches/updates.
This wouldn't actually save any I/O (since in the old regime the metapage
generally stayed in cache anyway), but it does provide a useful decrease
in bufmgr traffic in high-contention scenarios. Per my recent proposal.
implied by the predicate of a partial index being used to scan a table.
However, this optimization is unsafe in an UPDATE, DELETE, or SELECT FOR
UPDATE query, because the quals need to be rechecked by EvalPlanQual if
there's an update conflict. Per example from Jean-Samuel Reynaud.
transaction_timestamp() (just like now()).
Also update statement_timeout() to mention it is statement arrival time
that is measured.
Catalog version updated.
not named ones, and replace linear searches of the list with array indexing.
The named-parameter support has been dead code for many years anyway,
and recent profiling suggests that the searching was costing a noticeable
amount of performance for complex queries.
to track the number of LWLock acquisitions and the number of times we
block waiting for an LWLock, on a per-process basis. After having needed
this twice in the past few months, seems like it should go into CVS.
of rejecting palloc(0). Also, tweak like_selectivity() to avoid assuming
the presented pattern is nonempty; although that assumption is valid,
it doesn't really help much, and the new coding is more correct anyway
since it properly handles redundant wildcards. In combination these
changes should eliminate a Coverity warning noted by Martijn.
whenever we start to read within that file. The first page carries
extra identification information that really ought to be checked, but
as the code stood, this was only checked when we switched sequentially
into a new WAL file, or if by chance the starting checkpoint record was
within the first page. This patch ensures that we will detect bogus
'long header' information before we start replaying the WAL sequence.
8.0), and add as suggestion to use log_min_error_statement for this
purpose. I also fixed the code so the first EXECUTE has it's prepare,
rather than the last which is what was in the current code. Also remove
"protocol" prefix for SQL EXECUTE output because it is not accurate.
Backpatch to 8.1.X.
to occur between pg_start_backup() and pg_stop_backup(), even if the GUC
setting full_page_writes is OFF. Per discussion, doing this in combination
with the already-existing checkpoint during pg_start_backup() should ensure
safety against partial page updates being included in the backup. We do
not have to force full page writes to occur during normal PITR operation,
as I had first feared.
CREATE AGGREGATE aggname (input_type) (parameter_list)
along with the old syntax where the input type was named in the parameter
list. This fits more naturally with the way that the aggregate is identified
in DROP AGGREGATE and other utility commands; furthermore it has a natural
extension to handle multiple-input aggregates, where the basetype-parameter
method would get ugly. In fact, this commit fixes the grammar and all the
utility commands to support multiple-input aggregates; but DefineAggregate
rejects it because the executor isn't fixed yet.
I didn't do anything about treating agg(*) as a zero-input aggregate instead
of artificially making it a one-input aggregate, but that should be considered
in combination with supporting multi-input aggregates.
update no-longer-existing pages to fall through as no-ops, but make a note
of each page number referenced by such records. If we don't see a later
XLOG entry dropping the table or truncating away the page, complain at
the end of XLOG replay. Since this fixes the known failure mode for
full_page_writes = off, revert my previous band-aid patch that disabled
that GUC variable.
If a process abandons a wait in LockBufferForCleanup (in practice,
only happens if someone cancels a VACUUM) just before someone else
sends it a signal indicating the buffer is available, it was possible
for the wakeup to remain in the process' semaphore, causing misbehavior
next time the process waited for an lmgr lock. Rather than try to
prevent the race condition directly, it seems best to make the lock
manager robust against leftover wakeups, by having it repeat waiting
on the semaphore if the lock has not actually been granted or denied
yet.
alternatives ("|" symbol). The original coding allowed the added ^ and $
constraints to be absorbed into the first and last alternatives, producing
a pattern that would match more than it should. Per report from Eric Noriega.
I also changed the pattern to add an ARE director ("***:"), ensuring that
SIMILAR TO patterns do not change behavior if regex_flavor is changed. This
is necessary to make the non-capturing parentheses work, and seems like a
good idea on general principles.
Back-patched as far as 7.4. 7.3 also has the bug, but a fix seems impractical
because that version's regex engine doesn't have non-capturing parens.
upper-level insertion completes a previously-seen split, we cannot simply grab
the downlink block number out of the buffer, because the buffer could contain
a later state of the page --- or perhaps the page doesn't even exist at all
any more, due to relation truncation. These possibilities have been masked up
to now because the use of full_page_writes effectively ensured that no xlog
replay routine ever actually saw a page state newer than its own change.
Since we're deprecating full_page_writes in 8.1.*, there's no need to fix this
in existing release branches, but we need a fix in HEAD if we want to have any
hope of re-allowing full_page_writes. Accordingly, adjust the contents of
btree WAL records so that we can always get the downlink block number from the
WAL record rather than having to depend on buffer contents. Per report from
Kevin Grittner and Peter Brant.
Improve a few comments in related code while at it.
had a bad side-effect: it stopped finding plans that involved BitmapAnd
combinations of indexscans using both join and non-join conditions. Instead,
make choose_bitmap_and more aggressive about detecting redundancies between
BitmapOr subplans.
at least one join condition as an indexqual. Before bitmap indexscans, this
oversight didn't really cost much except for redundantly considering the
same join paths twice; but as of 8.1 it could result in silly bitmap scans
that would do the same BitmapOr twice and then BitmapAnd these together :-(
when trying to locate the referent of a RECORD variable. This fixes the
'record type has not been registered' failure reported by Stefan
Kaltenbrunner about a month ago. A side effect of the way I chose to
fix it is that most variable references in join conditions will now be
properly labeled with the variable's source table name, instead of the
not-too-helpful 'outer' or 'inner' we used to use.
output, ie, no OR immediately below an OR. Otherwise we get Asserts or
wrong answers for cases such as
select * from tenk1 a, tenk1 b
where (a.ten = b.ten and (a.unique1 = 100 or a.unique1 = 101))
or (a.hundred = b.hundred and a.unique1 = 42);
Per report from Rafael Martinez Guerrero.
Per recent discussion, this seems to be making the stats less accurate
rather than more so, particularly on Windows where PID values may be
reused very quickly. Patch by Peter Brant.
that apply the necessary domain constraint checks immediately. This fixes
cases where domain constraints went unchecked for statement parameters,
PL function local variables and results, etc. We can also eliminate existing
special cases for domains in places that had gotten it right, eg COPY.
Also, allow domains over domains (base of a domain is another domain type).
This almost worked before, but was disallowed because the original patch
hadn't gotten it quite right.
XLOG_BLCKSZ. This ought to help in preventing configuration mismatch
problems if anyone tries to ship PITR files between servers compiled
with different XLOG_BLCKSZ settings. Simon Riggs
instead a dedicated symbol. This probably makes no functional difference
for likely values of BLCKSZ, but it makes the intent clearer.
Simon Riggs, minor editorialization by Tom Lane.
functions are not strict, they will be called (passing a NULL first parameter)
during any attempt to input a NULL value of their datatype. Currently, all
our input functions are strict and so this commit does not change any
behavior. However, this will make it possible to build domain input functions
that centralize checking of domain constraints, thereby closing numerous holes
in our domain support, as per previous discussion.
While at it, I took the opportunity to introduce convenience functions
InputFunctionCall, OutputFunctionCall, etc to use in code that calls I/O
functions. This eliminates a lot of grotty-looking casts, but the main
motivation is to make it easier to grep for these places if we ever need
to touch them again.
used within WAL files. Historically this was the same as the data file
BLCKSZ, but there's no necessary connection, and it's possible that
performance gains might ensue from reducing XLOG_BLCKSZ. In any case
distinguishing two symbols should improve code clarity. This commit
does not actually change the page size, only provide the infrastructure
to make it possible to do so. initdb forced because of addition of a
field to pg_control.
Mark Wong, with some help from Simon Riggs and Tom Lane.
incrementally by successive inserts rather than by sorting the data.
We were only using the slow path during bootstrap, apparently because
when first written it failed during bootstrap --- but it works fine now
AFAICT. Removing it saves a hundred or so lines of code and produces
noticeably (~10%) smaller initial states of the system catalog indexes.
While that won't make much difference for heavily-modified catalogs,
for the more static ones there may be a useful long-term performance
improvement.
misleadingly-named WriteBuffer routine, and instead require routines that
change buffer pages to call MarkBufferDirty (which does exactly what it says).
We also require that they do so before calling XLogInsert; this takes care of
the synchronization requirement documented in SyncOneBuffer. Note that
because bufmgr takes the buffer content lock (in shared mode) while writing
out any buffer, it doesn't matter whether MarkBufferDirty is executed before
the buffer content change is complete, so long as the content change is
completed before releasing exclusive lock on the buffer. So it's OK to set
the dirtybit before we fill in the LSN.
This eliminates the former kluge of needing to set the dirtybit in LockBuffer.
Aside from making the code more transparent, we can also add some new
debugging assertions, in particular that the caller of MarkBufferDirty must
hold the buffer content lock, not merely a pin.
torn-page problems. This introduces some issues of its own, mainly
that there are now some critical sections of unreasonably broad scope,
but it's a step forward anyway. Further cleanup will require some
code refactoring that I'd prefer to get Oleg and Teodor involved in.
startup or recovery process. Since such a process isn't a real backend,
pgstat.c gets confused. This accounts for recent reports of strange
"invalid server process ID -1" log messages during crash recovery.
There isn't any point in attempting to make the report, since we'll discard
stats in such scenarios anyhow.
This commit doesn't make much functional change, but it does eliminate some
duplicated code --- for instance, PageIsNew tests are now done inside
XLogReadBuffer rather than by each caller.
The GIST xlog code still needs a lot of love, but I'll worry about that
separately.
have symlinks (ie, Windows). Although it'll never be called on to do anything
useful during normal operation on such a platform, it's still needed to
re-create dropped directories during WAL replay.
failures even when the hardware and OS did nothing wrong. Per recent analysis
of a problem report from Alex Bahdushka.
For the moment I've just diked out the test of the parameter, rather than
removing the GUC infrastructure and documentation, in case we conclude that
there's something salvageable there. There seems no chance of it being
resurrected in the 8.1 branch though.
passed extend = true whenever we are reading a page we intend to reinitialize
completely, even if we think the page "should exist". This is because it
might indeed not exist, if the relation got truncated sometime after the
current xlog record was made and before the crash we're trying to recover
from. These two thinkos appear to explain both of the old bug reports
discussed here:
http://archives.postgresql.org/pgsql-hackers/2005-05/msg01369.php
tuples as needed "to keep VACUUM from complaining", but actually there is
a more compelling reason to do it: failure to do so violates MVCC semantics.
This is because a pre-existing serializable transaction might try to use
the index after we finish (re)building it, and it might fail to find tuples
it should be able to see. We got this mostly right, but not in the case
of partial indexes: the code mistakenly discarded recently-dead tuples for
partial indexes. Fix that, and adjust the comments.
when an error occurs during xlog replay. Also, replace the former risky
'write into a fixed-size buffer with no overflow detection' API for XLOG
record description routines; use an expansible StringInfo instead. (The
latter accounts for most of the patch bulk.)
Qingqing Zhou
byte-swapping on the port number which causes the call to fail on Intel
Macs.
This patch uses htons() instead of htonl() and fixes this bug.
Ashley Clark
2005-05-13. When we find that a new inner tuple can't possibly match any
outer tuple (because it contains a NULL), we can't immediately skip the
tuple when we are in NEXTINNER state. Doing so can lead to emitting
multiple copies of the tuple in FillInner mode, because we may rescan the
tuple after returning to a previous marked tuple. Instead, proceed to
NEXTOUTER state the same as we used to do. After we've found that there's
no need to return to the marked position, we can go to SKIPINNER_ADVANCE
state instead of SKIP_TEST when the inner tuple is unmatchable; this
preserves the performance improvement. Per bug report from Bruce.
I also made a couple of cosmetic code rearrangements and added a regression
test for the problem.
The original coding stored the raw parser output (ColumnDef and TypeName
nodes) which was ugly, bulky, and wrong because it failed to create any
dependency on the referenced datatype --- and in fact would not track type
renamings and suchlike. Instead store a list of column type OIDs in the
RTE.
Also fix up general failure of recordDependencyOnExpr to do anything sane
about recording dependencies on datatypes. While there are many cases where
there will be an indirect dependency (eg if an operator returns a datatype,
the dependency on the operator is enough), we do have to record the datatype
as a separate dependency in examples like CoerceToDomain.
initdb forced because of change of stored rules.
during parse analysis, not only errors detected in the flex/bison stages.
This is per my earlier proposal. This commit includes all the basic
infrastructure, but locations are only tracked and reported for errors
involving column references, function calls, and operators. More could
be done later but this seems like a good set to start with. I've also
moved the ReportSyntaxErrorPosition logic out of psql and into libpq,
which should make it available to more people --- even within psql this
is an improvement because warnings weren't handled by ReportSyntaxErrorPosition.
similar constants if they were not previously defined. All these
constants must be defined by limits.h according to C89, so we can
safely assume they are present.
case where we run low on array slots before we run low on memory is much
more probable than I had thought, and so it's important to treat each
tape fairly in that case. To fix this, track per-tape slot allocations
just like we track per-tape space allocation. Also, in the FINALMERGE
code path avoid scanning all the input tapes when we really only need to
read from one. This should fix poor behavior with very large work_mem
as exhibited by Stefan Kaltenbrunner.
I didn't do anything about putting an upper bound on the number of tapes,
but maybe we should still consider that.
var_samp(), stddev_pop(), and stddev_samp(). var_samp() and stddev_samp()
are just renamings of the historical Postgres aggregates variance() and
stddev() -- the latter names have been kept for backward compatibility.
This patch includes updates for the documentation and regression tests.
The catversion has been bumped.
NB: SQL2003 requires that DISTINCT not be specified for any of these
aggregates. Per discussion on -patches, I have NOT implemented this
restriction: if the user asks for stddev(DISTINCT x), presumably they
know what they are doing.
performance issue during regular merge passes not only the 'final merge'
case. The original design contemplated that there would never be more
than about one free block per 'tape', hence no need for an efficient
method of keeping the free blocks sorted. But given the later addition
of merge preread behavior in tuplesort.c, there is likely to be about
work_mem worth of free blocks, which is not so small ... and for that
matter the number of tapes isn't necessarily small anymore either. So
we'd better get rid of the assumption entirely. Instead, I'm assuming
that the usage pattern will involve alternation between merge preread
and writing of a new run. This makes it reasonable to just add blocks
to the list without sorting during successive ltsReleaseBlock calls,
and then do a qsort() when we start getting ltsGetFreeBlock() calls.
Experimentation seems to confirm that there aren't many qsort calls
relative to the number of ltsReleaseBlock/ltsGetFreeBlock calls.
we are doing the final merge pass on-the-fly, and not writing the data
back onto a 'tape', the number of free blocks in the tape set will become
large, leading to a lot of time wasted in ltsReleaseBlock(). There is
really no need to track the free blocks anymore in this state, so add a
simple shutoff switch. Per report from Stefan Kaltenbrunner.
(respectively) to rename yylex and related symbols. Some were doing
it this way already, while others used not-too-reliable sed hacks in
the Makefiles. It's all nice and consistent now.
not likely ever to be implemented seeing it's been removed from SQL2003.
This allows getting rid of the 'filter' version of yylex() that we had in
parser.c, which should save at least a few microseconds in parsing.
- new function justify_interval(interval)
- modified function justify_hours(interval)
- modified function justify_days(interval)
These functions are defined to meet the requirements as discussed in
this thread. Specifically:
- justify_hours makes certain the sign bit on the hours
matches the sign bit on the days. It only checks the
sign bit on the days, and not the months, when
determining if the hours should be positive or negative.
After the call, -24 < hours < 24.
- justify_days makes certain the sign bit on the days
matches the sign bit on the months. It's behavior does
not depend on the hours, nor does it modify the hours.
After the call, -30 < days < 30.
- justify_interval makes sure the sign bits on all three
fields months, days, and hours are all the same. After
the call, -24 < hours < 24 AND -30 < days < 30.
Mark Dilger
columns of the grouping clause to avoid redundant sorts. The optimizer
is not currently capable of doing this, so this patch implements a
simple hack in the analysis phase (transformGroupClause): if any
subset of the GROUP BY clause matches a prefix of the ORDER BY list,
that prefix is moved to the front of the GROUP BY clause. This
shouldn't change the semantics of the query, and allows a redundant
sort to be avoided for queries like "GROUP BY a, b ORDER BY b".
In particular, ensure that enlargement of the memtuples[] array doesn't
fall foul of MaxAllocSize when work_mem is very large, and don't bother
enlarging it if that would force an immediate switch into 'tape' mode anyway.
we'll go over to disk-based sort if we reach that limit.
This fixes Stefan Kaltenbrunner's observation that sorting can suffer an
'invalid memory alloc request size' failure when sort_mem is set large
enough. It's unfortunately not so easy to fix in 8.1 ...
relations are still checked for permissions etc as soon as they are
opened. The original form of the patch could hold exclusive lock for a
long time on relations that the user doesn't even have permissions to
access, let alone truncate.
checkpoint in the bgwriter. This forestalls overflow of the fsync request
queue, which is not fatal but causes considerable performance degradation
when it occurs (because backends then have to do their own fsyncs). Per
patch from Itagaki Takahiro, modified a little bit by me.
are unnecessarily allocated on the heap rather than the stack. If the
StringInfo doesn't outlive the stack frame in which it is created,
there is no need to allocate it on the heap via makeStringInfo() --
stack allocation is faster. While it's not a big deal unless the
code is in a critical path, I don't see a reason not to save a few
cycles -- using stack allocation is not less readable.
I also cleaned up a bit of code along the way: moved variable
declarations into a more tightly-enclosing scope where possible,
fixed some pointless copying of strings in dblink, etc.
more compliant with the error message style guide. In particular,
errdetail should begin with a capital letter and end with a period,
whereas errmsg should not. I also fixed a few related issues in
passing, such as fixing the repeated misspelling of "lexeme" in
contrib/tsearch2 (per Tom's suggestion).
creation of a shell type. This allows a less hacky way of dealing with
the mutual dependency between a datatype and its I/O functions: make a
shell type, then make the functions, then define the datatype fully.
We should fix pg_dump to handle things this way, but this commit just deals
with the backend.
Martijn van Oosterhout, with some corrections by Tom Lane.
bits indicating which optional capabilities can actually be exercised
at runtime. This will allow Sort and Material nodes, and perhaps later
other nodes, to avoid unnecessary overhead in common cases.
This commit just adds the infrastructure and arranges to pass the correct
flag values down to plan nodes; none of the actual optimizations are here
yet. I'm committing this separately in case anyone wants to measure the
added overhead. (It should be negligible.)
Simon Riggs and Tom Lane
each tuple, as per my proposal of several days ago. Also, clean up
sort memory management by keeping all working data in a separate memory
context, and refine the handling of low-memory conditions.
the script is not executable as UCS_to_most.pl is in CVS. It also won't
pick up any custom setting of the perl version/location to use. This
patch calls perl scripts like $(PERL) $(srcdir)/script.pl.
Kris Jurka
possible ScanDirection alternatives rather than magic numbers
(-1, 0, 1). Also, use the ScanDirection macros in a few places
rather than directly checking whether `dir == ForwardScanDirection'
and the like. Per patch from James William Pye. His patch also
changed ScanDirection to be a "char" rather than an enum, which
I haven't applied.
allocates the control data. The per-tape buffers are allocated only
on first use. This saves memory in situations where tuplesort.c
overestimates the number of tapes needed (ie, there are fewer runs
than tapes). Also, this makes legitimate the coding in inittapes()
that includes tape buffer space in the maximum-memory calculation:
when inittapes runs, we've already expended the whole allowed memory
on tuple storage, and so we'd better not allocate all the tape buffers
until we've flushed some tuples out of memory.
with fixed merge order (fixed number of "tapes") was based on obsolete
assumptions, namely that tape drives are expensive. Since our "tapes"
are really just a couple of buffers, we can have a lot of them given
adequate workspace. This allows reduction of the number of merge passes
with consequent savings of I/O during large sorts.
Simon Riggs with some rework by Tom Lane
up a bunch of the support utilities.
In src/backend/utils/mb/Unicode remove nearly duplicate copies of the
UCS_to_XXX perl script and replace with one version to handle all generic
files. Update the Makefile so that it knows about all the map files.
This produces a slight difference in some of the map files, using a
uniform naming convention and not mapping the null character.
In src/backend/utils/mb/conversion_procs create a master utf8<->win
codepage function like the ISO 8859 versions instead of having a separate
handler for each conversion.
There is an externally visible change in the name of the win1258 to utf8
conversion. According to the documentation notes, it was named
incorrectly and this changes it to a standard name.
Running the Unicode mapping perl scripts has shown some additional mapping
changes in koi8r and iso8859-7.
we are not holding a buffer content lock; where it was, InterruptHoldoffCount
is positive and so we'd not respond to cancel signals as intended. Also
add missing vacuum_delay_point() call in btvacuumcleanup. This should fix
complaint from Evgeny Gridasov about failure to respond to SIGINT/SIGTERM
in a timely fashion (bug #2257).
Var referencing the subselect output. While this case could possibly be made
to work, it seems not worth expending effort on. Per report from Magnus
Naeslund(f).
id (CVE-2006-0553). Also fix related bug in SET SESSION AUTHORIZATION that
allows unprivileged users to crash the server, if it has been compiled with
Asserts enabled. The escalation-of-privilege risk exists only in 8.1.0-8.1.2.
However, the Assert-crash risk exists in all releases back to 7.3.
Thanks to Akio Ishida for reporting this problem.
comments on cluster global objects like databases, tablespaces, and
roles.
It touches a lot of places, but not much in the way of big changes. The
only design decision I made was to duplicate the query and manipulation
functions rather than to try and have them handle both shared and local
comments. I believe this is simpler for the code and not an issue for
callers because they know what type of object they are dealing with.
This has resulted in a shobj_description function analagous to
obj_description and backend functions [Create/Delete]SharedComments
mirroring the existing [Create/Delete]Comments functions.
pg_shdescription.h goes into src/include/catalog/
Kris Jurka
during the vacuumcleanup scan that we're going to do anyway. Should
save a few cycles (one calculation per page, not per tuple) as well
as not having to depend on assumptions about heap and index being
in step.
I think this could probably be made to work for GIST too, but that
code looks messy enough that I'm disinclined to try right now.
partial. None of the existing AMs do anything useful except counting
tuples when there's nothing to delete, and we can get a tuple count
from the heap as long as it's not a partial index. (hash actually can
skip anyway because it maintains a tuple count in the index metapage.)
GIST is not currently able to exploit this optimization because, due to
failure to index NULLs, GIST is always effectively partial. Possibly
we should fix that sometime.
Simon Riggs w/ some review by Tom Lane.
regardless of the current schema search path. Since CREATE OPERATOR CLASS
only allows one default opclass per datatype regardless of schemas, this
should have minimal impact, and it fixes problems with failure to find a
desired opclass while restoring dump files. Per discussion at
http://archives.postgresql.org/pgsql-hackers/2006-02/msg00284.php.
Remove now-redundant-or-unused code in typcache.c and namespace.c,
and backpatch as far as 8.0.
If the second output column value is 'a\nb', the 'b' should appear
in the second display column, rather than the first column as it
does now.
Change libpq's PQdsplen() to return more useful values.
> Note: this changes the PQdsplen function, it can now return zero or
> minus one which was not possible before. It doesn't appear anyone is
> actually using the functions other than psql but it is a change. The
> functions are not actually documentated anywhere so it's not like we're
> breaking a defined interface. The new semantics follow the Unicode
> standard.
BACKWARD COMPATIBLE CHANGE.
The only user-visible change I saw in the regression tests is that a
SELECT * on a table where all the columns have been dropped doesn't
return a blank line like before. This seems like a step forward.
Martijn van Oosterhout
the format on Tuple(Numeric) and the format to calculate(NumericVar)
are different. I understood that to reduce I/O. However, when many
comparisons or calculations of NUMERIC are executed, the conversion
of Numeric and NumericVar becomes a bottleneck.
It is profile result when "create index on NUMERIC column" is executed:
% cumulative self self total
time seconds seconds calls s/call s/call name
17.61 10.27 10.27 34542006 0.00 0.00 cmp_numerics
11.90 17.21 6.94 34542006 0.00 0.00 comparetup_index
7.42 21.54 4.33 71102587 0.00 0.00 AllocSetAlloc
7.02 25.64 4.09 69084012 0.00 0.00 set_var_from_num
4.87 28.48 2.84 69084012 0.00 0.00 alloc_var
4.79 31.27 2.79 142205745 0.00 0.00 AllocSetFreeIndex
4.55 33.92 2.65 34542004 0.00 0.00 cmp_abs
4.07 36.30 2.38 71101189 0.00 0.00 AllocSetFree
3.83 38.53 2.23 69084012 0.00 0.00 free_var
The create index command executes many comparisons of Numeric values.
Functions other than comparetup_index spent a lot of cycles for
conversion from Numeric to NumericVar.
An attached patch enables the comparison of Numeric values without
executing conversion to NumericVar. The execution time of that SQL
becomes half.
o Test SQL (index_test table has 1,000,000 tuples)
create index index_test_idx on index_test(num_col);
o Test results (executed the test five times)
(1)PentiumIII
original: 39.789s 36.823s 36.737s 37.752s 37.019s
patched : 18.560s 19.103s 18.830s 18.408s 18.853s
4.07 36.30 2.38 71101189 0.00 0.00 AllocSetFree
3.83 38.53 2.23 69084012 0.00 0.00 free_var
The create index command executes many comparisons of Numeric values.
Functions other than comparetup_index spent a lot of cycles for
conversion from Numeric to NumericVar.
An attached patch enables the comparison of Numeric values without
executing conversion to NumericVar. The execution time of that SQL
becomes half.
o Test SQL (index_test table has 1,000,000 tuples)
create index index_test_idx on index_test(num_col);
o Test results (executed the test five times)
(1)PentiumIII
original: 39.789s 36.823s 36.737s 37.752s 37.019s
patched : 18.560s 19.103s 18.830s 18.408s 18.853s
(2)Pentium4
original: 16.349s 14.997s 12.979s 13.169s 12.955s
patched : 7.005s 6.594s 6.770s 6.740s 6.828s
(3)Itanium2
original: 15.392s 15.447s 15.350s 15.370s 15.417s
patched : 7.413s 7.330s 7.334s 7.339s 7.339s
(4)Ultra Sparc
original: 64.435s 59.336s 59.332s 58.455s 59.781s
patched : 28.630s 28.666s 28.983s 28.744s 28.595s
Atsushi Ogawa
would basically punt in all cases for 'foo <> ALL (array)', which resulted
in a performance regression for NOT IN compared to what we were doing in
8.1 and before. Per report from Pavel Stehule.
relations: fix the executor so that we can have an Append plan on the
inside of a nestloop and still pass down outer index keys to index scans
within the Append, then generate such plans as if they were regular
inner indexscans. This avoids the need to evaluate the outer relation
multiple times.
... in fact, it will be applied now in any query whatsoever. I'm still
a bit concerned about the cycles that might be expended in failed proof
attempts, but given that CE is turned off by default, it's the user's
choice whether to expend those cycles or not. (Possibly we should
change the simple bool constraint_exclusion parameter to something
more fine-grained?)
thereby sharing code with the inheritance case. This puts the UNION-ALL-view
approach to partitioned tables on par with inheritance, so far as constraint
exclusion is concerned: it works either way. (Still need to update the docs
to say so.) The definition of "simple UNION ALL" is a little simpler than
I would like --- basically the union arms can only be SELECT * FROM foo
--- but it's good enough for partitioned-table cases.
it later. This fixes a problem where EXEC_BACKEND didn't have progname
set, causing a segfault if log_min_messages was set below debug2 and our
own snprintf.c was being used.
Also alway strdup() progname.
Backpatch to 8.1.X and 8.0.X.
inheritance trees on-the-fly, which pretty well constrained us to considering
only one way of planning inheritance, expand inheritance sets during the
planner prep phase, and build a side data structure that can be consulted
later to find which RTEs are members of which inheritance sets. As proof of
concept, use the data structure to plan joins against inheritance sets more
efficiently: we can now use indexes on the set members in inner-indexscan
joins. (The generated plans could be improved further, but it'll take some
executor changes.) This data structure will also support handling UNION ALL
subqueries in the same way as inheritance sets, but that aspect of it isn't
finished yet.
to avoid sharing substructure with the lower-level indexquals. This is
currently only an issue if there are SubPlans in the indexquals, which is
uncommon but not impossible --- see bug #2218 reported by Nicholas Vinen.
We use the same kluge for indexqual vs indexqualorig in the index scans
themselves ... would be nice to clean this up someday.
requested sort order. It was assuming that build_index_pathkeys always
generates a pathkey per index column, which was not true if implied equality
deduction had determined that two index columns were effectively equated to
each other. Simplest fix seems to be to install an option that causes
build_index_pathkeys to support this behavior as well as the original one.
Per report from Brian Hirt.
While we normally prefer the notation "foo.*" for a whole-row Var, that does
not work at SELECT top level, because in that context the parser will assume
that what is wanted is to expand the "*" into a list of separate target
columns, yielding behavior different from a whole-row Var. We have to emit
just "foo" instead in that context. Per report from Sokolov Yura.
and rely exclusively on the SQL type system to tell the difference between
the types. Prevent creation of invalid CIDR values via casting from INET
or set_masklen() --- both of these operations now silently zero any bits
to the right of the netmask. Remove duplicate CIDR comparison operators,
letting the type rely on the INET operators instead.
just refer to btree index entries as plain IndexTuples, which is what
they have been for a very long time. This is mostly just an exercise
in removing extraneous notation, but it does save a palloc/pfree cycle
per index insertion.
and non-required keys in a btree index scan, mark the required scankeys
with private flag bits SK_BT_REQFWD and/or SK_BT_REQBKWD. This seems
at least marginally clearer to me, and it eliminates a wired-into-the-
data-structure assumption that required keys are consecutive. Even though
that assumption will remain true for the foreseeable future, having it
in there makes the code seem more complex than necessary.
and DELETE. If specified, the alias must be used instead of the full
table name. Also, the alias currently cannot be used in the SET clause
of UPDATE.
Patch from Atsushi Ogawa, various editorialization by Neil Conway.
Along the way, make the rowtypes regression test pass if add_missing_from
is enabled, and add a new (skeletal) regression test for DELETE.
to try to create a log segment file concurrently, but the code erroneously
specified O_EXCL to open(), resulting in a needless failure. Before 7.4,
it was even a PANIC condition :-(. Correct code is actually simpler than
what we had, because we can just say O_CREAT to start with and not need a
second open() call. I believe this accounts for several recent reports of
hard-to-reproduce "could not create file ...: File exists" errors in both
pg_clog and pg_subtrans.
Continue to support GRANT ON [TABLE] for sequences for backward
compatibility; issue warning for invalid sequence permissions.
[Backward compatibility warning message.]
Add USAGE permission for sequences that allows only currval() and
nextval(), not setval().
Mention object name in grant/revoke warnings because of possible
multi-object operations.
temp table not only our own process' tables. It's not real important
since vacuum.c will skip temp tables anyway, but might as well make the
code do what it claims to do.
index's support-function cache (in index_getprocinfo). Since none of that
data can change for an index that's in active use, it seems sufficient to
treat all open indexes the same way we were treating "nailed" system indexes
--- that is, just re-read the pg_class row and leave the rest of the relcache
entry strictly alone. The pg_class re-read might not be strictly necessary
either, but since the reltablespace and relfilenode can change in normal
operation it seems safest to do it. (We don't support changing any of the
other info about an index at all, at the moment.)
Back-patch as far as 8.0. It might be possible to adapt the patch to 7.4,
but it would take more work than I care to expend for such a low-probability
problem. 7.3 is out of luck for sure.
occurs when it tries to heap_open pg_tablespace. When control returns to
smgrcreate, that routine will be holding a dangling pointer to a closed
SMgrRelation, resulting in mayhem. This is of course a consequence of
the violation of proper module layering inherent in having smgr.c call
a tablespace command routine, but the simplest fix seems to be to change
the locking mechanism. There's no real need for TablespaceCreateDbspace
to touch pg_tablespace at all --- it's only opening it as a way of locking
against a parallel DROP TABLESPACE command. A much better answer is to
create a special-purpose LWLock to interlock these two operations.
This drops TablespaceCreateDbspace quite a few layers down the food chain
and makes it something reasonably safe for smgr to call.
This is utterly insignificant in normal operation, but it becomes a
problem during cache inval stress testing. The original coding in fact
had no leak --- the 8.0 List rewrite created the issue. I wonder whether
list_concat should pfree the discarded header?
files: avoid creating stats hashtable entries for tables that aren't being
touched except by vacuum/analyze, ensure that entries for dropped tables are
removed promptly, and tweak the data layout to avoid storing useless struct
padding. Also improve the performance of pgstat_vacuum_tabstat(), and make
sure that autovacuum invokes it exactly once per autovac cycle rather than
multiple times or not at all. This should cure recent complaints about 8.1
showing much higher stats I/O volume than was seen in 8.0. It'd still be a
good idea to revisit the design with an eye to not re-writing the entire
stats dataset every half second ... but that would be too much to backpatch,
I fear.
cursors. Patch from Joachim Wieland, review and ediorialization by Neil
Conway. The view lists cursors defined by DECLARE CURSOR, using SPI, or
via the Bind message of the frontend/backend protocol. This means the
view does not list the unnamed portal or the portal created to implement
EXECUTE. Because we do list SPI portals, there might be more rows in
this view than you might expect if you are using SPI implicitly (e.g.
via a procedural language).
Per recent discussion on -hackers, the query string included in the
view for cursors defined by DECLARE CURSOR is based on
debug_query_string. That means it is not accurate if multiple queries
separated by semicolons are submitted as one query string. However,
there doesn't seem a trivial fix for that: debug_query_string
is better than nothing. I also changed SPI_cursor_open() to include
the source text for the portal it creates: AFAICS there is no reason
not to do this.
Update the documentation and regression tests, bump the catversion.
are two basically different kinds of scankeys, and we ought to try harder
to indicate which is used in each place in the code. I've chosen the names
"search scankey" and "insertion scankey", though you could make about
as good an argument for "operator scankey" and "comparison function
scankey".
an array of regtype, rather than an array of OIDs. This is likely to
be more useful to user, and the type OID can easily be obtained by
casting a regtype value to OID. Per suggestion from Tom.
Update the documentation and regression tests, and bump the catversion.
data type is unspecified or is declared to be "unknown", the type will
be inferred from the context in which the parameter is used. This was
already possible for protocol-level prepared statements.
isn't being used anywhere anymore, and there seems no point in a generic
index_keytest() routine when two out of three remaining access methods
aren't using it. Also, add a comment documenting a convention for
letting access methods define private flag bits in ScanKey sk_flags.
There are no such flags at the moment but I'm thinking about changing
btree's handling of "required keys" to use flag bits in the keys
rather than a count of required key positions. Also, if some AM did
still want SK_NEGATE then it would be reasonable to treat it as a private
flag bit.
transaction as aborted. Since we only call XactLockTableWait on XIDs
that we believe to be currently running, the odds of this code ever
actually firing are minimal. It's certainly unnecessary, since a
transaction that's not either running or committed will be presumed
aborted anyway. What's more, it's not hard to imagine scenarios where
this could result in corrupting pg_clog: for instance, if a bogus XID
somehow got passed to XactLockTableWait. I think the code probably
dates from the ancient era when we didn't have TransactionIdIsInProgress;
back then it may have been necessary, but now I think it's a waste of
cycles and potentially dangerous. Per discussion with Qingqing Zhou
and Karsten Hilbert.
permissions on the functions and operators contained in the opclass.
Since we already require superuser privilege to create an operator class,
there's no expansion-of-privilege hazard here, but if someone were to get
the idea of building an opclass containing functions that need security
restrictions, we'd better warn them off. Also, change the permission
checks from have-execute-privilege to have-ownership, and then comment
them all out since they're dead code anyway under the superuser restriction.
type definition. Because use of a type's I/O conversion functions isn't
access-checked, CREATE TYPE amounts to granting public execute permissions
on the functions, and so allowing it to anybody means that someone could
theoretically gain access to a function he's not supposed to be able to
execute. The parameter-type restrictions already enforced by CREATE TYPE
make it fairly unlikely that this oversight is meaningful in practice,
but still it seems like a good idea to plug the hole going forward.
Also, document the implicit grant just in case anybody gets the idea of
building I/O functions that might need security restrictions.
fmgr_info(), in the TopMemoryContext. I couldn't see that the code
actually leaked, but in general I think it's fragile to assume that
pfree'ing an FmgrInfo along with its fn_extra field is enough to
reclaim all the resources allocated by fmgr_info(). I changed the
code to do its allocations in a new child context of
TopMemoryContext, MbProcContext. When we want to release the
allocations we can just reset the context, which is cleaner.
our own command (or more generally, xmin = our xact and cmin >= current
command ID) should not be seen as good. Else we may try to update rows
we already updated. This error was inserted last August while fixing the
even bigger problem that the old coding wouldn't see *any* tuples inserted
by our own transaction as good. Per report from Euler Taveira de Oliveira.
rather than "return expr;" -- the latter style is used in most of the
tree. I kept the parentheses when they were necessary or useful because
the return expression was complex.
listed in the column's most-common-values statistics entry. This gives
us an exact selectivity result for the portion of the column population
represented by the MCV list, which can be a big leg up in accuracy if
that's a large fraction of the population. The heuristics involving
pattern contents and prefix are applied only to the part of the population
not included in the MCV list.
and nail a couple more system indexes into cache. This doesn't make
any difference in normal system operation, but when forcing constant
cache resets it's difficult to get through the rules regression test
without these changes.
Bruce Momjian
Tom Lane
Alvaro Herrera
Teodor Sigaev
Peter Eisentraut
Neil Conway
Tatsuo Ishii
Andrew Dunstan