It appears that this will be faster for all but the shortest strings;
at least one some platforms, memcmp() can use word-at-a-time comparisons.
Noah Misch, somewhat pared down.
On MacOS X, and apparently also on other BSD-derived systems, attaching
a debugger causes getppid() to return the pid of the debugging process
rather than the actual parent PID. As a result, debugging the
autovacuum launcher, startup process, or WAL sender on such systems
causes it to exit, because the previous coding of PostmasterIsAlive()
detects postmaster death by testing whether getppid() == PostmasterPid.
Work around that behavior by checking the return value of getppid()
more carefully. If it's PostmasterPid, the postmaster must be alive;
if it's 1, assume the postmaster is dead. If it's any other value,
assume we've been debugged and fall through to the less-reliable
kill() test.
Review by Tom Lane.
This case can arise if a transaction has written data, but only to
temporary tables. Loss of the commit record in case of a crash won't
matter, because the temporary tables will be lost anyway.
Reviewed by Heikki Linnakangas and Simon Riggs.
Since we're not multithreaded it only provides marginally useful
information, and it does require a newer version of the Platform SDK
than we target. We may want to reconsider this in the future along
with a fix for MinGW.
eval_const_expressions() can replace CaseTestExprs with constants when
the surrounding CASE's test expression is a constant. This confuses
ruleutils.c's heuristic for deparsing simple-form CASEs, leading to
Assert failures or "unexpected CASE WHEN clause" errors. I had put in
a hack solution for that years ago (see commit
514ce7a331 of 2006-10-01), but bug #5794
from Peter Speck shows that that solution failed to cover all cases.
Fortunately, there's a much better way, which came to me upon reflecting
that Peter's "CASE TRUE WHEN" seemed pretty redundant: we can "simplify"
the simple-form CASE to the general form of CASE, by simply omitting the
constant test expression from the rebuilt CASE construct. This is
intuitively valid because there is no need for the executor to evaluate
the test expression at runtime; it will never be referenced, because any
CaseTestExprs that would have referenced it are now replaced by constants.
This won't save a whole lot of cycles, since evaluating a Const is pretty
cheap, but a cycle saved is a cycle earned. In any case it beats kluging
ruleutils.c still further. So this patch improves const-simplification
and reverts the previous change in ruleutils.c.
Back-patch to all supported branches. The bug exists in 8.1 too, but it's
out of warranty.
After parsing a parenthesized subexpression, we must pop all pending
ANDs and NOTs off the stack, just like the case for a simple operand.
Per bug #5793.
Also fix clones of this routine in contrib/intarray and contrib/ltree,
where input of types query_int and ltxtquery had the same problem.
Back-patch to all supported versions.
Add support for collecting "minidump" style crash dumps on
Windows, by setting up an exception handling filter. Crash
dumps will be generated in PGDATA/crashdumps if the directory
is created (the existance of the directory is used as on/off
switch for the generation of the dumps).
Craig Ringer and Magnus Hagander
This prevents the word "waiting" from briefly disappearing from the ps
status line when ResolveRecoveryConflictWithVirtualXIDs begins a new
iteration of the outer loop.
Along the way, remove some useless pgstat_report_waiting() calls;
the startup process doesn't appear in pg_stat_activity.
Fujii Masao
These comments were not updated when we added the EXEC_BACKEND
mechanism for Windows, even though it rendered them inaccurate.
Also unify two unnecessarily-separate #ifdef __alpha code blocks.
We don't actually need optreset, because we can easily fix the code to
ensure that it's cleanly restartable after having completed a scan over the
argv array; which is the only case we need to restart in. Getting rid of
it avoids a class of interactions with the system libraries and allows
reversion of my change of yesterday in postmaster.c and postgres.c.
Back-patch to 8.4. Before that the getopt code was a bit different anyway.
libpq connection, per report from Magnus. This happens only on GIT
master and only on Win32 because that is the platform where "" maps to
an IP address (localhost).
The mingw people don't appear to care about compatibility with non-GNU
versions of getopt, so force use of our own copy of getopt on Windows.
Also, ensure that we make use of optreset when using our own copy.
Per report from Andrew Dunstan. Back-patch to all versions supported
on Windows.
This patch replaces Guttman's generalized split method with a simple
sort-by-center-points algorithm. Since the data is only one-dimensional
we don't really need the slow and none-too-stable Guttman method.
This is in part a bug fix, since seg has the same size_alpha versus
size_beta typo that was recently fixed in contrib/cube. It seems
prudent to apply this rather aggressive fix only in HEAD, though.
Back branches will just get the typo fix.
Alexander Korotkov, reviewed by Yeb Havinga
Allow INSERT INTO, UPDATE, and DELETE FROM to be completed with
either the name of a table (as before) or the name of a view with
an appropriate INSTEAD OF rule.
Along the way, allow CREATE TRIGGER to be completed with INSTEAD OF,
as well as BEFORE and AFTER.
David Fetter, reviewed by Itagaki Takahiro
This commit replaces pg_class.relistemp with pg_class.relpersistence;
and also modifies the RangeVar node type to carry relpersistence rather
than istemp. It also removes removes rd_istemp from RelationData and
instead performs the correct computation based on relpersistence.
For clarity, we add three new macros: RelationNeedsWAL(),
RelationUsesLocalBuffers(), and RelationUsesTempNamespace(), so that we
can clarify the purpose of each check that previous depended on
rd_istemp.
This is intended as infrastructure for the upcoming unlogged tables
patch, as well as for future possible work on global temporary tables.
We were failing to zero out some pg_stat_database counters that have
been added since the initial pgstats coding. This is a bug, but not
back-patching the fix since changing this behavior in a minor release
seems a cure worse than the disease.
Report and patch by Tomas Vondra.
1. Don't reimplement S_ISDIR() and S_ISREG() badly.
2. Don't reimplement access() badly.
This code appears to have been copied from ancient versions of the
corresponding backend routines, and not patched to incorporate subsequent
fixes (see my commits of 2008-03-31 and 2010-01-14 respectively).
It might be a good idea to change it to just *call* those routines,
but for now I'll just transpose these fixes over.
mkdir_p and check_data_dir will be useful in CREATE TABLESPACE, since we
have agreed that that command should handle subdirectory creation just like
initdb creates the PGDATA directory. Push them into src/port/ so that they
are available to both initdb and the backend. Rename to pg_mkdir_p and
pg_check_dir, just to be on the safe side. Add FreeBSD's copyright notice
to pgmkdirp.c, since that's where the code came from originally (this
really should have been in initdb.c). Very marginal code/comment cleanup.
Purely cosmetic patch to make our coding standards more consistent ---
we were doing symbolic some places and octal other places. This patch
fixes all C-coded uses of mkdir, chmod, and umask. There might be some
other calls I missed. Inconsistency noted while researching tablespace
directory permissions issue.
The original coding in tuplestore_trim() was only meant to work efficiently
in cases where each trim call deleted most of the tuples in the store.
Which, in fact, was the pattern of the original usage with a Material node
supporting mark/restore operations underneath a MergeJoin. However,
WindowAgg now uses tuplestores and it has considerably less friendly
trimming behavior. In particular it can attempt to trim one tuple at a
time off a large tuplestore. tuplestore_trim() had O(N^2) runtime in this
situation because of repeatedly shifting its tuple pointer array. Fix by
avoiding shifting the array until a reasonably large number of tuples have
been deleted. This can waste some pointer space, but we do still reclaim
the tuples themselves, so the percentage wastage should be pretty small.
Per Jie Li's report of slow percent_rank() evaluation. cume_dist() and
ntile() would certainly be affected as well, along with any other window
function that has a moving frame start and requires reading substantially
ahead of the current row.
Back-patch to 8.4, where window functions were introduced. There's no
need to tweak it before that.
With hundreds of thousands of TOC entries, the repeated searches in
reduce_dependencies() become the dominant cost. Get rid of that searching
by constructing reverse-dependency lists, which we can do in O(N) time
during the fix_dependencies() preprocessing. I chose to store the reverse
dependencies as DumpId arrays for consistency with the forward-dependency
representation, and keep the previously-transient tocsByDumpId[] array
around to locate actual TOC entry structs quickly from dump IDs.
While this fixes the slow case reported by Vlad Arkhipov, there is still
a potential for O(N^2) behavior with sufficiently many tables:
fix_dependencies itself, as well as mark_create_done and
inhibit_data_for_failed_table, are doing repeated searches to deal with
table-to-table-data dependencies. Possibly this work could be extended
to deal with that, although the latter two functions are also used in
non-parallel restore where we currently don't run fix_dependencies.
Another TODO is that we fail to parallelize restore of multiple blobs
at all. This appears to require changes in the archive format to fix.
Back-patch to 9.0 where the problem was reported. 8.4 has potential issues
as well; but since it doesn't create a separate TOC entry for each blob,
it's at much less risk of having enough TOC entries to cause real problems.
Hot Standby conflicts only with tuples that were visible at
some point. So ignore tuples from aborted transactions or for
tuples updated/deleted during the inserting transaction when
generating the conflict transaction ids.
Following detailed analysis and test case by Noah Misch.
Original report covered btree delete records, correctly observed
by Heikki Linnakangas that this applies to other cases also.
Fix covers all sources of cleanup records via common code.
Robert Haas
Alvaro Herrera
Magnus Hagander
Tom Lane
Bruce Momjian
Itagaki Takahiro
Peter Eisentraut
Simon Riggs