summaryrefslogtreecommitdiff
path: root/src/backend
AgeCommit message (Collapse)Author
2011-04-19Avoid changing an index's indcheckxmin horizon during REINDEX.Tom Lane
There can never be a need to push the indcheckxmin horizon forward, since any HOT chains that are actually broken with respect to the index must pre-date its original creation. So we can just avoid changing pg_index altogether during a REINDEX operation. This offers a cleaner solution than my previous patch for the problem found a few days ago that we mustn't try to update pg_index while we are reindexing it. System catalog indexes will always be created with indcheckxmin = false during initdb, and with this modified code we should never try to change their pg_index entries. This avoids special-casing system catalogs as the former patch did, and should provide a performance benefit for many cases where REINDEX formerly caused an index to be considered unusable for a short time. Back-patch to 8.3 to cover all versions containing HOT. Note that this patch changes the API for index_build(), but I believe it is unlikely that any add-on code is calling that directly.
2011-04-19Revert "Prevent incorrect updates of pg_index while reindexing pg_index itself."Tom Lane
This reverts commit a03e3e1fd1d4ecfeb1096aeb7854b717061a75d9 of 2011-04-15. There's a better way to do it, which will follow shortly.
2011-04-15Prevent incorrect updates of pg_index while reindexing pg_index itself.Tom Lane
The places that attempt to change pg_index.indcheckxmin during a reindexing operation cannot be executed safely if pg_index itself is the subject of the operation. This is the explanation for a couple of recent reports of VACUUM FULL failing with ERROR: duplicate key value violates unique constraint "pg_index_indexrelid_index" DETAIL: Key (indexrelid)=(2678) already exists. However, there isn't any real need to update indcheckxmin in such a situation, if we assume that pg_index can never contain a truly broken HOT chain. This assumption holds if new indexes are never created on it during concurrent operations, which is something we don't consider safe for any system catalog, not just pg_index. Accordingly, modify the code to not manipulate indcheckxmin when reindexing any system catalog. Back-patch to 8.3, where HOT was introduced. The known failure scenarios involve 9.0-style VACUUM FULL, so there might not be any real risk before 9.0, but let's not assume that.
2011-04-14Translation updatesPeter Eisentraut
2011-04-13Ensure mark_dummy_rel doesn't create dangling pointers in RelOptInfos.Tom Lane
When we are doing GEQO join planning, the current memory context is a short-lived context that will be reset at the end of geqo_eval(). However, the RelOptInfos for base relations are set up before that and then re-used across many GEQO cycles. Hence, any code that modifies a baserel during join planning has to be careful not to put pointers to the short-lived context into the baserel struct. mark_dummy_rel got this wrong, leading to easy-to-reproduce-once-you-know-how crashes in 8.4, as reported off-list by Leo Carson of SDSC. Some improvements made in 9.0 make it difficult to demonstrate the crash in 9.0 or HEAD; but there's no doubt that there's still a risk factor here, so patch all branches that have the function. (Note: 8.3 has a similar function, but it's only applied to joinrels and thus is not a hazard.)
2011-04-13On HP/UX, the structs used by ioctl(SIOCGLIFCONF) are named differentlyHeikki Linnakangas
than on other platforms, and only IPv6 addresses are returned. Because of those two issues, fall back to ioctl(SIOCGIFCONF) on HP/UX, so that it at least compiles and finds IPv4 addresses. This function is currently only used for interpreting samehost/samenet in pg_hba.conf, which isn't that critical.
2011-04-13Revert the patch to check if we've reached end-of-backup also when doingHeikki Linnakangas
crash recovery, and throw an error if not. hubert depesz lubaczewski pointed out that that situation also happens in the crash recovery following a system crash that happens during an online backup. We might want to do something smarter in 9.1, like put the check back for backups taken with pg_basebackup, but that's for another patch.
2011-04-13On IA64 architecture, we check the depth of the register stack in additionHeikki Linnakangas
to the regular stack. The code to do that is platform and compiler specific, add support for the HP-UX native compiler.
2011-04-12Don't make "replication" magical as a user name, only as a database name, in ↵Andrew Dunstan
pg_hba.conf. Per gripe from Josh Berkus. Backported from commit ed557a373c406bbb2a1843544ebbd856ca4cac47.
2011-04-12Be more wary of missing statistics in eqjoinsel_semi().Tom Lane
In particular, if we don't have real ndistinct estimates for both sides, fall back to assuming that half of the left-hand rows have join partners. This is what was done in 8.2 and 8.3 (cf nulltestsel() in those versions). It's pretty stupid but it won't lead us to think that an antijoin produces no rows out, as seen in recent example from Uwe Schroeder.
2011-04-07Modernize dlopen interface code for FreeBSD and OpenBSD.Tom Lane
Remove the hard-wired assumption that __mips__ (and only __mips__) lacks dlopen in FreeBSD and OpenBSD. This assumption is outdated at least for OpenBSD, as per report from an anonymous 9.1 tester. We can perfectly well use HAVE_DLOPEN instead to decide which code to use. Some other cosmetic adjustments to make freebsd.c, netbsd.c, and openbsd.c exactly alike.
2011-04-01Avoid palloc before CurrentMemoryContext is set up on win32Magnus Hagander
Instead, write the unconverted output - it will be in the wrong encoding, but at least we don't crash. Rushabh Lathia
2011-03-30Check that we've reached end-of-backup also when we're not performingHeikki Linnakangas
archive recovery. It's possible to restore an online backup without recovery.conf, by simply copying all the necessary WAL files to pg_xlog. "pg_basebackup -x" does that too. That's the use case where this cross-check is useful. Backpatch to 9.0. We used to do this in earlier versins, but in 9.0 the code was inadvertently changed so that the check is only performed after archive recovery. Fujii Masao.
2011-03-28Prevent a rowtype from being included in itself.Tom Lane
Eventually we might be able to allow that, but it's not clear how many places need to be fixed to prevent infinite recursion when there's a direct or indirect inclusion of a rowtype in itself. One such place is CheckAttributeType(), which will recurse to stack overflow in cases such as those exhibited in bug #5950 from Alex Perepelica. If we were sure it was the only such place, we could easily modify the code added by this patch to stop the recursion without a complaint ... but it probably isn't the only such place. Hence, throw error until such time as someone is excited enough about this type of usage to put work into making it safe. Back-patch as far as 8.3. 8.2 doesn't have the recursive call in CheckAttributeType in the first place, so I see no need to add code there in the absence of clear evidence of a problem elsewhere.
2011-03-23Prevent intermittent hang in recovery from bgwriter interaction.Simon Riggs
Startup process waited for cleanup lock but when hot_standby = off the pid was not registered, so that the bgwriter would not wake the waiting process as intended.
2011-03-22Avoid potential deadlock in InitCatCachePhase2().Tom Lane
Opening a catcache's index could require reading from that cache's own catalog, which of course would acquire AccessShareLock on the catalog. So the original coding here risks locking index before heap, which could deadlock against another backend trying to get exclusive locks in the normal order. Because InitCatCachePhase2 is only called when a backend has to start up without a relcache init file, the deadlock was seldom seen in the field. (And by the same token, there's no need to worry about any performance disadvantage; so not much point in trying to distinguish exactly which catalogs have the risk.) Bug report, diagnosis, and patch by Nikhil Sontakke. Additional commentary by me. Back-patch to all supported branches.
2011-03-11On further reflection, we'd better do the same in int.c.Tom Lane
We previously heard of the same problem in int24div(), so there's not a good reason to suppose the problem is confined to cases involving int8.
2011-03-11Put in some more safeguards against executing a division-by-zero.Tom Lane
Add dummy returns before every potential division-by-zero in int8.c, because apparently further "improvements" in gcc's optimizer have enabled it to break functions that weren't broken before. Aurelien Jarno, via Martin Pitt
2011-03-08Don't throw a warning if vacuum sees PD_ALL_VISIBLE flag set on a page thatHeikki Linnakangas
contains newly-inserted tuples that according to our OldestXmin are not yet visible to everyone. The value returned by GetOldestXmin() is conservative, and it can move backwards on repeated calls, so if we see that contradiction between the PD_ALL_VISIBLE flag and status of tuples on the page, we have to assume it's because an earlier vacuum calculated a higher OldestXmin value, and all the tuples really are visible to everyone. We have received several reports of this bug, with the "PD_ALL_VISIBLE flag was incorrectly set in relation ..." warning appearing in logs. We were finally able to hunt it down with David Gould's help to run extra diagnostics in an environment where this happened frequently. Also reword the warning, per Robert Haas' suggestion, to not imply that the PD_ALL_VISIBLE flag is necessarily at fault, as it might also be a symptom of corruption on a tuple header. Backpatch to 8.4, where the PD_ALL_VISIBLE flag was introduced.
2011-02-21Fix dangling-pointer problem in before-row update trigger processing.Tom Lane
ExecUpdate checked for whether ExecBRUpdateTriggers had returned a new tuple value by seeing if the returned tuple was pointer-equal to the old one. But the "old one" was in estate->es_junkFilter's result slot, which would be scribbled on if we had done an EvalPlanQual update in response to a concurrent update of the target tuple; therefore we were comparing a dangling pointer to a live one. Given the right set of circumstances we could get a false match, resulting in not forcing the tuple to be stored in the slot we thought it was stored in. In the case reported by Maxim Boguk in bug #5798, this led to "cannot extract system attribute from virtual tuple" failures when trying to do "RETURNING ctid". I believe there is a very-low-probability chance of more serious errors, such as generating incorrect index entries based on the original rather than the trigger-modified version of the row. In HEAD, change all of ExecBRInsertTriggers, ExecIRInsertTriggers, ExecBRUpdateTriggers, and ExecIRUpdateTriggers so that they continue to have similar APIs. In the back branches I just changed ExecBRUpdateTriggers, since there is no bug in the ExecBRInsertTriggers case.
2011-02-17Fix tsmatchsel() to account properly for null rows.Tom Lane
ts_typanalyze.c computes MCE statistics as fractions of the non-null rows, which seems fairly reasonable, and anyway changing it in released versions wouldn't be a good idea. But then ts_selfuncs.c has to account for that. Failure to do so results in overestimates in columns with a significant fraction of null documents. Back-patch to 8.4 where this stuff was introduced. Jesper Krogh
2011-02-16Fix bogus test for hypothetical indexes in get_actual_variable_range().Tom Lane
That function was supposing that indexoid == 0 for a hypothetical index, but that is not likely to be true in any non-toy implementation of an index adviser, since assigning a fake OID is the only way to know at EXPLAIN time which hypothetical index got selected. Fix by adding a flag to IndexOptInfo to mark hypothetical indexes. Back-patch to 9.0 where get_actual_variable_range() was added. Gurjeet Singh
2011-02-15Add CheckTableNotInUse calls in DROP TABLE and DROP INDEX.Tom Lane
Recent releases had a check on rel->rd_refcnt in heap_drop_with_catalog, but failed to cover the possibility of pending trigger events at DROP time. (Before 8.4 we didn't even check the refcnt.) When the trigger events were eventually fired, you'd get "could not open relation with OID nnn" errors, as in recent report from strk. Better to throw a suitable error when the DROP is attempted. Also add a similar check in DROP INDEX. Back-patch to all supported branches.
2011-02-09Fix improper matching of resjunk column names for FOR UPDATE in subselect.Tom Lane
Flattening of subquery range tables during setrefs.c could lead to the rangetable indexes in PlanRowMark nodes not matching up with the column names previously assigned to the corresponding resjunk ctid (resp. tableoid or wholerow) columns. Typical symptom would be either a "cannot extract system attribute from virtual tuple" error or an Assert failure. This wasn't a problem before 9.0 because we didn't support FOR UPDATE below the top query level, and so the final flattening could never renumber an RTE that was relevant to FOR UPDATE. Fix by using a plan-tree-wide unique number for each PlanRowMark to label the associated resjunk columns, so that the number need not change during flattening. Per report from David Johnston (though I'm darned if I can see how this got past initial testing of the relevant code). Back-patch to 9.0.
2011-02-01Create new errcode for recovery conflict caused by db drop on master.Simon Riggs
Previously reported as ERRCODE_ADMIN_SHUTDOWN, this case is now reported as ERRCODE_DATABASE_DROPPED. No message text change. Unlikely to happen on most servers, so low impact change to allow session poolers to correctly handle this situation. Tatsuo Ishii and Simon Riggs
2011-02-01Fix wrong error reports in 'number of array dimensions exceeds theItagaki Takahiro
maximum allowed' messages, that have reported one-less dimensions. Alexey Klyukin
2011-01-31Fix error code for canceling statement due to conflict with recovery.Simon Riggs
All retryable conflict errors now have an error code that indicates that a retry is possible, correcting my incomplete fix of 2010/05/12 Tatsuo Ishii and Simon Riggs, input from Robert Haas and Florian Pflug
2011-01-30Make reduce_outer_joins() smarter about semijoins.Tom Lane
reduce_outer_joins() mistakenly treated a semijoin like a left join for purposes of deciding whether not-null constraints created by the join's quals could be passed down into the join's left-hand side (possibly resulting in outer-join simplification there). Actually, semijoin works like inner join for this purpose, ie, we do not need to see any rows that can't possibly satisfy the quals. Hence, two-line fix to treat semi and inner joins alike. Per observation by Andres Freund about a performance gripe from Yazan Suleiman. Back-patch to 8.4, since this oversight has been there since the current handling of semijoins was implemented.
2011-01-27Don't include <asm/ia64regs.h> unnecessarily.Tom Lane
We only need that header when compiling with icc, since the gcc variant of ia64_get_bsp() uses in-line assembly code. Per report from Frank Brendel, the header doesn't exist on all IA64 platforms; so don't include it unless we need it.
2011-01-27Translation updates for release 9.0.3Peter Eisentraut
2011-01-20Make ALTER TABLE revalidate uniqueness and exclusion constraints.Robert Haas
Failure to do so can lead to constraint violations. This was broken by commit 1ddc2703a936d03953657f43345460b9242bbed1 on 2010-02-07, so back-patch to 9.0. Noah Misch. Regression test by me.
2011-01-17Fix miscalculation of itemsafter in array_set_slice().Tom Lane
If the slice to be assigned to was before the existing array lower bound (requiring at least one null element to spring into existence to fill the gap), the code miscalculated how many entries needed to be copied from the old array's null bitmap. This could result in trashing the array's data area (as seen in bug #5840 from Karsten Loesing), or worse. This has been broken since we first allowed the behavior of assigning to non-adjacent slices, in 8.2. Back-patch to all affected versions.
2011-01-17Before exiting walreceiver, fsync() all the WAL received.Heikki Linnakangas
Otherwise WAL recovery will replay the un-flushed WAL after walreceiver has exited, which can lead to a non-recoverable standby if the system crashes hard at that point.
2011-01-13Fix the logic in libpqrcv_receive() to determine if there's any incoming dataHeikki Linnakangas
that can be read without blocking. It used to conclude that there isn't, even though there was data in the socket receive buffer. That lead walreceiver to flush the WAL after every received chunk, potentially causing big performance issues. Backpatch to 9.0, because the performance impact can be very significant.
2011-01-12Fix PlanRowMark/ExecRowMark structures to handle inheritance correctly.Tom Lane
In an inherited UPDATE/DELETE, each target table has its own subplan, because it might have a column set different from other targets. This means that the resjunk columns we add to support EvalPlanQual might be at different physical column numbers in each subplan. The EvalPlanQual rewrite I did for 9.0 failed to account for this, resulting in possible misbehavior or even crashes during concurrent updates to the same row, as seen in a recent report from Gordon Shannon. Revise the data structure so that we track resjunk column numbers separately for each subplan. I also chose to move responsibility for identifying the physical column numbers back to executor startup, instead of assuming that numbers derived during preprocess_targetlist would stay valid throughout subsequent massaging of the plan. That's a bit slower, so we might want to consider undoing it someday; but it would complicate the patch considerably and didn't seem justifiable in a bug fix that has to be back-patched to 9.0.
2010-12-28Avoid unexpected conversion overflow in planner for distant date values.Tom Lane
The "date" type supports a wider range of dates than int64 timestamps do. However, there is pre-int64-timestamp code in the planner that assumes that all date values can be converted to timestamp with impunity. Fortunately, what we really need out of the conversion is always a double (float8) value; so even when the date is out of timestamp's range it's possible to produce a sane answer. All we need is a code path that doesn't try to force the result into int64. Per trouble report from David Rericha. Back-patch to all supported versions. Although this is surely a corner case, there's not much point in advertising a date range wider than timestamp's if we will choke on such values in unexpected places.
2010-12-19Fix up handling of simple-form CASE with constant test expression.Tom Lane
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 514ce7a331c5bea8e55b106d624e55732a002295 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.
2010-12-19Fix erroneous parsing of tsquery input "... & !(subexpression) | ..."Tom Lane
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.
2010-12-16Remove optreset from src/port/ implementations of getopt and getopt_long.Tom Lane
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.
2010-12-15Fix up getopt() reset management so it works on recent mingw.Tom Lane
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.
2010-12-13Translation updates for release 9.0.2Peter Eisentraut
2010-12-10Fix efficiency problems in tuplestore_trim().Tom Lane
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.
2010-12-10Reduce spurious Hot Standby conflicts from never-visible records.Simon Riggs
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. Includes additional fix compared to commit on HEAD
2010-12-08Force default wal_sync_method to be fdatasync on Linux.Tom Lane
Recent versions of the Linux system header files cause xlogdefs.h to believe that open_datasync should be the default sync method, whereas formerly fdatasync was the default on Linux. open_datasync is a bad choice, first because it doesn't actually outperform fdatasync (in fact the reverse), and second because we try to use O_DIRECT with it, causing failures on certain filesystems (e.g., ext4 with data=journal option). This part of the patch is largely per a proposal from Marti Raudsepp. More extensive changes are likely to follow in HEAD, but this is as much change as we want to back-patch. Also clean up confusing code and incorrect documentation surrounding the fsync_writethrough option. Those changes shouldn't result in any actual behavioral change, but I chose to back-patch them anyway to keep the branches looking similar in this area. In 9.0 and HEAD, also do some copy-editing on the WAL Reliability documentation section. Back-patch to all supported branches, since any of them might get used on modern Linux versions.
2010-12-07Fix bugs in the hot standby known-assigned-xids tracking logic. If there'sHeikki Linnakangas
an old transaction running in the master, and a lot of transactions have started and finished since, and a WAL-record is written in the gap between the creating the running-xacts snapshot and WAL-logging it, recovery will fail with "too many KnownAssignedXids" error. This bug was reported by Joachim Wieland on Nov 19th. In the same scenario, when fewer transactions have started so that all the xids fit in KnownAssignedXids despite the first bug, a more serious bug arises. We incorrectly initialize the clog code with the oldest still running transaction, and when we see the WAL record belonging to a transaction with an XID larger than one that committed already before the checkpoint we're recovering from, we zero the clog page containing the already committed transaction, leading to data loss. In hindsight, trying to track xids in the known-assigned-xids array before seeing the running-xacts record was too complicated. To fix that, hold XidGenLock while the running-xacts snapshot is taken and WAL-logged. That ensures that no transaction can begin or end in that gap, so that in recvoery we know that the snapshot contains all transactions running at that point in WAL.
2010-12-06Add a stack overflow check to copyObject().Tom Lane
There are some code paths, such as SPI_execute(), where we invoke copyObject() on raw parse trees before doing parse analysis on them. Since the bison grammar is capable of building heavily nested parsetrees while itself using only minimal stack depth, this means that copyObject() can be the front-line function that hits stack overflow before anything else does. Accordingly, it had better have a check_stack_depth() call. I did a bit of performance testing and found that this slows down copyObject() by only a few percent, so the hit ought to be negligible in the context of complete processing of a query. Per off-list report from Toshihide Katayama. Back-patch to all supported branches.
2010-12-06Fix two typos, by Fujii Masao.Heikki Linnakangas
2010-12-01Prevent inlining a SQL function with multiple OUT parameters.Tom Lane
There were corner cases in which the planner would attempt to inline such a function, which would result in a failure at runtime due to loss of information about exactly what the result record type is. Fix by disabling inlining when the function's recorded result type is RECORD. There might be some sub-cases where inlining could still be allowed, but this is a simple and backpatchable fix, so leave refinements for another day. Per bug #5777 from Nate Carson. Back-patch to all supported branches. 8.1 happens to avoid a core-dump here, but it still does the wrong thing.
2010-11-29Move call to GetTopTransactionId() earlier in LockAcquire(),Simon Riggs
removing an infrequently occurring race condition in Hot Standby. An xid must be assigned before a lock appears in shared memory, rather than immediately after, else GetRunningTransactionLocks() may see InvalidTransactionId, causing assertion failures during lock processing on standby. Bug report and diagnosis by Fujii Masao, fix by me.
2010-11-19Fix leakage of cost_limit when multiple autovacuum workers are active.Tom Lane
When using default autovacuum_vac_cost_limit, autovac_balance_cost relied on VacuumCostLimit to contain the correct global value ... but after the first time through in a particular worker process, it didn't, because we'd trashed it in previous iterations. Depending on the state of other autovac workers, this could result in a steady reduction of the effective cost_limit setting as a particular worker processed more and more tables, causing it to go slower and slower. Spotted by Simon Poole (bug #5759). Fix by saving and restoring the GUC variables in the loop in do_autovacuum. In passing, improve a few comments. Back-patch to 8.3 ... the cost rebalancing code has been buggy since it was put in.