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* Limit overall indentation in rule/view dumps.Tom Lane2014-04-30
| | | | | | | | | | | | | | | | | Continuing to indent no matter how deeply nested we get doesn't really do anything for readability; what's worse, it results in O(N^2) total whitespace, which can become a performance and memory-consumption issue. To address this, once we get past 40 characters of indentation, reduce the indentation step distance 4x, and also limit the maximum indentation by reducing it modulo 40. This latter choice is a bit weird at first glance, but it seems to preserve readability better than a simple cap would do. Back-patch to 9.3, because since commit 62e666400d the performance issue is a hazard for pg_dump. Greg Stark and Tom Lane
* Fix indentation of JOIN clauses in rule/view dumps.Tom Lane2014-04-30
| | | | | | | | | | | | | | | | | | | | The code attempted to outdent JOIN clauses further left than the parent FROM keyword, which was odd in any case, and led to inconsistent formatting since in simple cases the clauses couldn't be moved any further left than that. And it left a permanent decrement of the indentation level, causing subsequent lines to be much further left than they should be (again, this couldn't be seen in simple cases for lack of indentation to give up). After a little experimentation I chose to make it indent JOIN keywords two spaces from the parent FROM, which is one space more than the join's lefthand input in cases where that appears on a different line from FROM. Back-patch to 9.3. This is a purely cosmetic change, and the bug is quite old, so that may seem arbitrary; but we are going to be making some other changes to the indentation behavior in both HEAD and 9.3, so it seems reasonable to include this in 9.3 too. I committed this one first because its effects are more visible in the regression test results as they currently stand than they will be later.
* Improve planner to drop constant-NULL inputs of AND/OR where it's legal.Tom Lane2014-04-29
| | | | | | | | | | | | | | | | | | | In general we can't discard constant-NULL inputs, since they could change the result of the AND/OR to be NULL. But at top level of WHERE, we do not need to distinguish a NULL result from a FALSE result, so it's okay to treat NULL as FALSE and then simplify AND/OR accordingly. This is a very ancient oversight, but in 9.2 and later it can lead to failure to optimize queries that previous releases did optimize, as a result of more aggressive parameter substitution rules making it possible to reduce more subexpressions to NULL constants. This is the root cause of bug #10171 from Arnold Scheffler. We could alternatively have fixed that by teaching orclauses.c to ignore constant-NULL OR arms, but it seems better to get rid of them globally. I resisted the temptation to back-patch this change into all active branches, but it seems appropriate to back-patch as far as 9.2 so that there will not be performance regressions of the kind shown in this bug.
* Fix two bugs in WAL-logging of GIN pending-list pages.Heikki Linnakangas2014-04-28
| | | | | | | | | | | | | | | | | | In writeListPage, never take a full-page image of the page, because we have all the information required to re-initialize in the WAL record anyway. Before this fix, a full-page image was always generated, unless full_page_writes=off, because when the page is initialized its LSN is always 0. In stable-branches, keep the code to restore the backup blocks if they exist, in case that the WAL is generated with an older minor version, but in master Assert that there are no full-page images. In the redo routine, add missing "off++". Otherwise the tuples are added to the page in reverse order. That happens to be harmless because we always scan and remove all the tuples together, but it was clearly wrong. Also, it was masked by the first bug unless full_page_writes=off, because the page was always restored from a full-page image. Backpatch to all supported versions.
* Fix race when updating a tuple concurrently locked by another processAlvaro Herrera2014-04-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a tuple is locked, and this lock is later upgraded either to an update or to a stronger lock, and in the meantime some other process tries to lock, update or delete the same tuple, it (the tuple) could end up being updated twice, or having conflicting locks held. The reason for this is that the second updater checks for a change in Xmax value, or in the HEAP_XMAX_IS_MULTI infomask bit, after noticing the first lock; and if there's a change, it restarts and re-evaluates its ability to update the tuple. But it neglected to check for changes in lock strength or in lock-vs-update status when those two properties stayed the same. This would lead it to take the wrong decision and continue with its own update, when in reality it shouldn't do so but instead restart from the top. This could lead to either an assertion failure much later (when a multixact containing multiple updates is detected), or duplicate copies of tuples. To fix, make sure to compare the other relevant infomask bits alongside the Xmax value and HEAP_XMAX_IS_MULTI bit, and restart from the top if necessary. Also, in the belt-and-suspenders spirit, add a check to MultiXactCreateFromMembers that a multixact being created does not have two or more members that are claimed to be updates. This should protect against other bugs that might cause similar bogus situations. Backpatch to 9.3, where the possibility of multixacts containing updates was introduced. (In prior versions it was possible to have the tuple lock upgraded from shared to exclusive, and an update would not restart from the top; yet we're protected against a bug there because there's always a sleep to wait for the locking transaction to complete before continuing to do anything. Really, the fact that tuple locks always conflicted with concurrent updates is what protected against bugs here.) Per report from Andrew Dunstan and Josh Berkus in thread at http://www.postgresql.org/message-id/534C8B33.9050807@pgexperts.com Bug analysis by Andres Freund.
* Reset pg_stat_activity.xact_start during PREPARE TRANSACTION.Tom Lane2014-04-24
| | | | | | | | | | | | | | | Once we've completed a PREPARE, our session is not running a transaction, so its entry in pg_stat_activity should show xact_start as null, rather than leaving the value as the start time of the now-prepared transaction. I think possibly this oversight was triggered by faulty extrapolation from the adjacent comment that says PrepareTransaction should not call AtEOXact_PgStat, so tweak the wording of that comment. Noted by Andres Freund while considering bug #10123 from Maxim Boguk, although this error doesn't seem to explain that report. Back-patch to all active branches.
* Update obsolete comments.Heikki Linnakangas2014-04-23
| | | | We no longer have a TLI field in the page header.
* Fix typos in comment.Heikki Linnakangas2014-04-23
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* Set the all-visible flag on heap page before writing WAL record, not after.Heikki Linnakangas2014-04-17
| | | | | | | | | | | | | | | | If we set the all-visible flag after writing WAL record, and XLogInsert takes a full-page image of the page, the image would not include the flag. We will then proceed to set the VM bit, which would then be set without the corresponding all-visible flag on the heap page. Found by comparing page images on master and standby, after writing/replaying each WAL record. (There is still a discrepancy: the all-visible flag won't be set after replaying the HEAP_CLEAN record, even though it is set in the master. However, it will be set when replaying the HEAP2_VISIBLE record and setting the VM bit, so the all-visible flag and VM bit are always consistent on the standby, even though they are momentarily out-of-sync with master) Backpatch to 9.3 where this code was introduced.
* Fix object identities for text search objectsAlvaro Herrera2014-04-16
| | | | | | | We were neglecting to schema-qualify them. Backpatch to 9.3, where object identities were introduced as a concept by commit f8348ea32ec8.
* Use AF_UNSPEC not PF_UNSPEC in getaddrinfo calls.Tom Lane2014-04-16
| | | | | | | | | | | | | | | | | | According to the Single Unix Spec and assorted man pages, you're supposed to use the constants named AF_xxx when setting ai_family for a getaddrinfo call. In a few places we were using PF_xxx instead. Use of PF_xxx appears to be an ancient BSD convention that was not adopted by later standardization. On BSD and most later Unixen, it doesn't matter much because those constants have equivalent values anyway; but nonetheless this code is not per spec. In the same vein, replace PF_INET by AF_INET in one socket() call, which wasn't even consistent with the other socket() call in the same function let alone the remainder of our code. Per investigation of a Cygwin trouble report from Marco Atzeri. It's probably a long shot that this will fix his issue, but it's wrong in any case.
* check socket creation errors against PGINVALID_SOCKETBruce Momjian2014-04-16
| | | | | | | | Previously, in some places, socket creation errors were checked for negative values, which is not true for Windows because sockets are unsigned. This masked socket creation errors on Windows. Backpatch through 9.0. 8.4 doesn't have the infrastructure to fix this.
* Use correctly-sized buffer when zero-filling a WAL file.Heikki Linnakangas2014-04-16
| | | | | | I mixed up BLCKSZ and XLOG_BLCKSZ when I changed the way the buffer is allocated a couple of weeks ago. With the default settings, they are both 8k, but they can be changed at compile-time.
* Fix hot standby bug with GiST scans.Heikki Linnakangas2014-04-08
| | | | | | | | | | Don't reset the rightlink of a page when replaying a page update record. This was a leftover from pre-hot standby days, when it was not possible to have scans concurrent with WAL replay. Resetting the right-link was not necessary back then either, but it was done for the sake of tidiness. But with hot standby, it's wrong, because a concurrent scan might still need it. Backpatch all versions with hot standby, 9.0 and above.
* Assert that strong-lock count is >0 everywhere it's decremented.Robert Haas2014-04-07
| | | | | | | | | | The one existing assertion of this type has tripped a few times in the buildfarm lately, but it's not clear whether the problem is really originating there or whether it's leftovers from a trip through one of the other two paths that lack a matching assertion. So add one. Since the same bug(s) most likely exist(s) in the back-branches also, back-patch to 9.2, where the fast-path lock mechanism was added.
* Block signals earlier during postmaster startup.Tom Lane2014-04-05
| | | | | | | | | | | | | | | | | | | | | | | Formerly, we set up the postmaster's signal handling only when we were about to start launching subprocesses. This is a bad idea though, as it means that for example a SIGINT arriving before that will kill the postmaster instantly, perhaps leaving lockfiles, socket files, shared memory, etc laying about. We'd rather that such a signal caused orderly postmaster termination including releasing of those resources. A simple fix is to move the PostmasterMain stanza that initializes signal handling to an earlier point, before we've created any such resources. Then, an early-arriving signal will be blocked until we're ready to deal with it in the usual way. (The only part that really needs to be moved up is blocking of signals, but it seems best to keep the signal handler installation calls together with that; for one thing this ensures the kernel won't drop any signals we wished to get. The handlers won't get invoked in any case until we unblock signals in ServerLoop.) Per a report from MauMau. He proposed changing the way "pg_ctl stop" works to deal with this, but that'd just be masking one symptom not fixing the core issue. It's been like this since forever, so back-patch to all supported branches.
* Fix processing of PGC_BACKEND GUC parameters on Windows.Tom Lane2014-04-05
| | | | | | | | | | | | | | | EXEC_BACKEND builds (i.e., Windows) failed to absorb values of PGC_BACKEND parameters if they'd been changed post-startup via the config file. This for example prevented log_connections from working if it were turned on post-startup. The mechanism for handling this case has always been a bit of a kluge, and it wasn't revisited when we implemented EXEC_BACKEND. While in a normal forking environment new backends will inherit the postmaster's value of such settings, EXEC_BACKEND backends have to read the settings from the CONFIG_EXEC_PARAMS file, and they were mistakenly rejecting them. So this case has always been broken in the Windows port; so back-patch to all supported branches. Amit Kapila
* Fix tablespace creation WAL replay to work on Windows.Tom Lane2014-04-04
| | | | | | | | | | The code segment that removes the old symlink (if present) wasn't clued into the fact that on Windows, symlinks are junction points which have to be removed with rmdir(). Backpatch to 9.0, where the failing code was introduced. MauMau, reviewed by Muhammad Asif Naeem and Amit Kapila
* Allow "-C variable" and "--describe-config" even to root users.Tom Lane2014-04-04
| | | | | | | | | | | | | | | | | | | | | | | | There's no really compelling reason to refuse to do these read-only, non-server-starting options as root, and there's at least one good reason to allow -C: pg_ctl uses -C to find out the true data directory location when pointed at a config-only directory. On Windows, this is done before dropping administrator privileges, which means that pg_ctl fails for administrators if and only if a config-only layout is used. Since the root-privilege check is done so early in startup, it's a bit awkward to check for these switches. Make the somewhat arbitrary decision that we'll only skip the root check if -C is the first switch. This is not just to make the code a bit simpler: it also guarantees that we can't misinterpret a --boot mode switch. (While AuxiliaryProcessMain doesn't currently recognize any such switch, it might have one in the future.) This is no particular problem for pg_ctl, and since the whole behavior is undocumented anyhow, it's not a documentation issue either. (--describe-config only works as the first switch anyway, so this is no restriction for that case either.) Back-patch to 9.2 where pg_ctl first began to use -C. MauMau, heavily edited by me
* Fix bogus time printout in walreceiver's debug log messages.Tom Lane2014-04-04
| | | | | | | | | | | | | The displayed sendtime and receipttime were always exactly equal, because somebody forgot that timestamptz_to_str returns a static buffer (thereby simplifying life for most callers, at the cost of complicating it for those who need two results concurrently). Apply the same pstrdup solution used by the other call sites with this issue. Back-patch to 9.2 where the faulty code was introduced. Per bug #9849 from Haruka Takatsuka, though this is not exactly his patch. Possibly we should change timestamptz_to_str's API, but I wouldn't want to do so in the back branches.
* Move multixid allocation out of critical section.Heikki Linnakangas2014-04-04
| | | | | | It can fail if you run out of memory. This call was added in 9.3, so backpatch to 9.3 only.
* Avoid allocations in critical sections.Heikki Linnakangas2014-04-04
| | | | If a palloc in a critical section fails, it becomes a PANIC.
* Fix non-equivalence of VARIADIC and non-VARIADIC function call formats.Tom Lane2014-04-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For variadic functions (other than VARIADIC ANY), the syntaxes foo(x,y,...) and foo(VARIADIC ARRAY[x,y,...]) should be considered equivalent, since the former is converted to the latter at parse time. They have indeed been equivalent, in all releases before 9.3. However, commit 75b39e790 made an ill-considered decision to record which syntax had been used in FuncExpr nodes, and then to make equal() test that in checking node equality --- which caused the syntaxes to not be seen as equivalent by the planner. This is the underlying cause of bug #9817 from Dmitry Ryabov. It might seem that a quick fix would be to make equal() disregard FuncExpr.funcvariadic, but the same commit made that untenable, because the field actually *is* semantically significant for some VARIADIC ANY functions. This patch instead adopts the approach of redefining funcvariadic (and aggvariadic, in HEAD) as meaning that the last argument is a variadic array, whether it got that way by parser intervention or was supplied explicitly by the user. Therefore the value will always be true for non-ANY variadic functions, restoring the principle of equivalence. (However, the planner will continue to consider use of VARIADIC as a meaningful difference for VARIADIC ANY functions, even though some such functions might disregard it.) In HEAD, this change lets us simplify the decompilation logic in ruleutils.c, since the funcvariadic/aggvariadic flag tells directly whether to print VARIADIC. However, in 9.3 we have to continue to cope with existing stored rules/views that might contain the previous definition. Fortunately, this just means no change in ruleutils.c, since its existing behavior effectively ignores funcvariadic for all cases other than VARIADIC ANY functions. In HEAD, bump catversion to reflect the fact that FuncExpr.funcvariadic changed meanings; this is sort of pro forma, since I don't believe any built-in views are affected. Unfortunately, this patch doesn't magically fix everything for affected 9.3 users. After installing 9.3.5, they might need to recreate their rules/views/indexes containing variadic function calls in order to get everything consistent with the new definition. As in the cited bug, the symptom of a problem would be failure to use a nominally matching index that has a variadic function call in its definition. We'll need to mention this in the 9.3.5 release notes.
* Avoid palloc in critical section in GiST WAL-logging.Heikki Linnakangas2014-04-03
| | | | | | | | | | | | | | | | Memory allocation can fail if you run out of memory, and inside a critical section that will lead to a PANIC. Use conservatively-sized arrays in stack instead. There was previously no explicit limit on the number of pages a GiST split can produce, it was only limited by the number of LWLocks that can be held simultaneously (100 at the moment). This patch adds an explicit limit of 75 pages. That should be plenty, a typical split shouldn't produce more than 2-3 page halves. The bug has been there forever, but only backpatch down to 9.1. The code was changed significantly in 9.1, and it doesn't seem worth the risk or trouble to adapt this for 9.0 and 8.4.
* Fix assorted issues in client host name lookup.Tom Lane2014-04-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The code for matching clients to pg_hba.conf lines that specify host names (instead of IP address ranges) failed to complain if reverse DNS lookup failed; instead it silently didn't match, so that you might end up getting a surprising "no pg_hba.conf entry for ..." error, as seen in bug #9518 from Mike Blackwell. Since we don't want to make this a fatal error in situations where pg_hba.conf contains a mixture of host names and IP addresses (clients matching one of the numeric entries should not have to have rDNS data), remember the lookup failure and mention it as DETAIL if we get to "no pg_hba.conf entry". Apply the same approach to forward-DNS lookup failures, too, rather than treating them as immediate hard errors. Along the way, fix a couple of bugs that prevented us from detecting an rDNS lookup error reliably, and make sure that we make only one rDNS lookup attempt; formerly, if the lookup attempt failed, the code would try again for each host name entry in pg_hba.conf. Since more or less the whole point of this design is to ensure there's only one lookup attempt not one per entry, the latter point represents a performance bug that seems sufficient justification for back-patching. Also, adjust src/port/getaddrinfo.c so that it plays as well as it can with this code. Which is not all that well, since it does not have actual support for rDNS lookup, but at least it should return the expected (and required by spec) error codes so that the main code correctly perceives the lack of functionality as a lookup failure. It's unlikely that PG is still being used in production on any machines that require our getaddrinfo.c, so I'm not excited about working harder than this. To keep the code in the various branches similar, this includes back-patching commits c424d0d1052cb4053c8712ac44123f9b9a9aa3f2 and 1997f34db4687e671690ed054c8f30bb501b1168 into 9.2 and earlier. Back-patch to 9.1 where the facility for hostnames in pg_hba.conf was introduced.
* Fix bugs in manipulation of PgBackendStatus.st_clienthostname.Tom Lane2014-04-01
| | | | | | | | | | Initialization of this field was not being done according to the st_changecount protocol (it has to be done within the changecount increment range, not outside). And the test to see if the value should be reported as null was wrong. Noted while perusing uses of Port.remote_hostname. This was wrong from the introduction of this code (commit 4a25bc145), so back-patch to 9.1.
* Mark FastPathStrongRelationLocks volatile.Robert Haas2014-03-31
| | | | | | | | | Otherwise, the compiler might decide to move modifications to data within this structure outside the enclosing SpinLockAcquire / SpinLockRelease pair, leading to shared memory corruption. This may or may not explain a recent lmgr-related buildfarm failure on prairiedog, but it needs to be fixed either way.
* Count buffers dirtied due to hints in pgBufferUsage.shared_blks_dirtied.Robert Haas2014-03-31
| | | | | | | | | | Previously, such buffers weren't counted, with the possible result that EXPLAIN (BUFFERS) and pg_stat_statements would understate the true number of blocks dirtied by an SQL statement. Back-patch to 9.2, where this counter was introduced. Amit Kapila
* Don't forget to flush XLOG_PARAMETER_CHANGE record.Fujii Masao2014-03-26
| | | | Backpatch to 9.0 where XLOG_PARAMETER_CHANGE record was instroduced.
* Address ccvalid/ccnoinherit in TupleDesc support functions.Noah Misch2014-03-23
| | | | | | | | | equalTupleDescs() neglected both of these ConstrCheck fields, and CreateTupleDescCopyConstr() neglected ccnoinherit. At this time, the only known behavior defect resulting from these omissions is constraint exclusion disregarding a CHECK constraint validated by an ALTER TABLE VALIDATE CONSTRAINT statement issued earlier in the same transaction. Back-patch to 9.2, where these fields were introduced.
* Properly check for readdir/closedir() failuresBruce Momjian2014-03-21
| | | | | | | Clear errno before calling readdir() and handle old MinGW errno bug while adding full test coverage for readdir/closedir failures. Backpatch through 8.4.
* Fix memory leak during regular expression execution.Tom Lane2014-03-19
| | | | | | | | For a regex containing backrefs, pg_regexec() might fail to free all the sub-DFAs that were created during execution, resulting in a permanent (session lifespan) memory leak. Problem was introduced by me in commit 587359479acbbdc95c8e37da40707e37097423f5. Per report from Sandro Santilli; diagnosis by Greg Stark.
* During index build, check and elog (not just Assert) for broken HOT chain.Tom Lane2014-03-17
| | | | | | | The recently-fixed bug in WAL replay could result in not finding a parent tuple for a heap-only tuple. The existing code would either Assert or generate an invalid index entry, neither of which is desirable. Throw a regular error instead.
* Fix bug in clean shutdown of walsender that pg_receiving is connecting to.Fujii Masao2014-03-17
| | | | | | | | | | | | | | On clean shutdown, walsender waits for all WAL to be replicated to a standby, and exits. It determined whether that replication had been completed by checking whether its sent location had been equal to a standby's flush location. Unfortunately this condition never becomes true when the standby such as pg_receivexlog which always returns an invalid flush location is connecting to walsender, and then walsender waits forever. This commit changes walsender so that it just checks a standby's write location if a flush location is invalid. Back-patch to 9.1 where enough infrastructure for this exists.
* Translation updatesPeter Eisentraut2014-03-16
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* Make punctuation consistentPeter Eisentraut2014-03-16
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* Prevent interrupts while reporting non-ERROR elog messages.Tom Lane2014-03-13
| | | | | | | | | | | | | | | | This should eliminate the risk of recursive entry to syslog(3), which appears to be the cause of the hang reported in bug #9551 from James Morton. Arguably, the real problem here is auth.c's willingness to turn on ImmediateInterruptOK while executing fairly wide swaths of backend code. We may well need to work at narrowing the code ranges in which the authentication_timeout interrupt is enabled. For the moment, though, this is a cheap and reasonably noninvasive fix for a field-reported failure; the other approach would be complex and not necessarily bug-free itself. Back-patch to all supported branches.
* Avoid transaction-commit race condition while receiving a NOTIFY message.Tom Lane2014-03-13
| | | | | | | | | | | | | | | | | | | | | | | | Use TransactionIdIsInProgress, then TransactionIdDidCommit, to distinguish whether a NOTIFY message's originating transaction is in progress, committed, or aborted. The previous coding could accept a message from a transaction that was still in-progress according to the PGPROC array; if the client were fast enough at starting a new transaction, it might fail to see table rows added/updated by the message-sending transaction. Which of course would usually be the point of receiving the message. We noted this type of race condition long ago in tqual.c, but async.c overlooked it. The race condition probably cannot occur unless there are multiple NOTIFY senders in action, since an individual backend doesn't send NOTIFY signals until well after it's done committing. But if two senders commit in close succession, it's certainly possible that we could see the second sender's message within the race condition window while responding to the signal from the first one. Per bug #9557 from Marko Tiikkaja. This patch is slightly more invasive than what he proposed, since it removes the now-redundant TransactionIdDidAbort call. Back-patch to 9.0, where the current NOTIFY implementation was introduced.
* In WAL replay, restore GIN metapage unconditionally to avoid torn page.Heikki Linnakangas2014-03-12
| | | | | | | | | | | | | | | | We don't take a full-page image of the GIN metapage; instead, the WAL record contains all the information required to reconstruct it from scratch. But to avoid torn page hazards, we must re-initialize it from the WAL record every time, even if it already has a greater LSN, similar to how normal full page images are restored. This was highly unlikely to cause any problems in practice, because the GIN metapage is small. We rely on an update smaller than a 512 byte disk sector to be atomic elsewhere, at least in pg_control. But better safe than sorry, and this would be easy to overlook if more fields are added to the metapage so that it's no longer small. Reported by Noah Misch. Backpatch to all supported versions.
* Fix dangling smgr_owner pointer when a fake relcache entry is freed.Heikki Linnakangas2014-03-07
| | | | | | | | | | | | A fake relcache entry can "own" a SmgrRelation object, like a regular relcache entry. But when it was free'd, the owner field in SmgrRelation was not cleared, so it was left pointing to free'd memory. Amazingly this apparently hasn't caused crashes in practice, or we would've heard about it earlier. Andres found this with Valgrind. Report and fix by Andres Freund, with minor modifications by me. Backpatch to all supported versions.
* Avoid memcpy() with same source and destination address.Heikki Linnakangas2014-03-07
| | | | | | | The behavior of that is undefined, although unlikely to lead to problems in practice. Found by running regression tests with Valgrind.
* Fix typo in comment.Heikki Linnakangas2014-03-07
| | | | Forgot to "git add" it earlier.
* Avoid getting more than AccessShareLock when deparsing a query.Tom Lane2014-03-06
| | | | | | | | | | | | | | | | | | | | In make_ruledef and get_query_def, we have long used AcquireRewriteLocks to ensure that the querytree we are about to deparse is up-to-date and the schemas of the underlying relations aren't changing. Howwever, that function thinks the query is about to be executed, so it acquires locks that are stronger than necessary for the purpose of deparsing. Thus for example, if pg_dump asks to deparse a rule that includes "INSERT INTO t", we'd acquire RowExclusiveLock on t. That results in interference with concurrent transactions that might for example ask for ShareLock on t. Since pg_dump is documented as being purely read-only, this is unexpected. (Worse, it used to actually be read-only; this behavior dates back only to 8.1, cf commit ba4200246.) Fix this by adding a parameter to AcquireRewriteLocks to tell it whether we want the "real" execution locks or only AccessShareLock. Report, diagnosis, and patch by Dean Rasheed. Back-patch to all supported branches.
* Send keepalives from walsender even when busy sending WAL.Heikki Linnakangas2014-03-06
| | | | | | | | | | | | | | | | If walsender doesn't hear from the client for the time specified by wal_sender_timeout, it will conclude the connection or client is dead, and disconnect. When half of wal_sender_timeout has elapsed, it sends a ping to the client, leaving it the remainig half of wal_sender_timeout to respond. However, it only checked if half of wal_sender_timeout had elapsed when it was about to sleep, so if it was busy sending WAL to the client for long enough, it would not send the ping request in time. Then the client would not know it needs to send a reply, and the walsender will disconnect even though the client is still alive. Fix that. Andres Freund, reviewed by Robert Haas, and some further changes by me. Backpatch to 9.3. Earlier versions relied on the client to send the keepalives on its own, and hence didn't have this problem.
* Don't reject ROW_MARK_REFERENCE rowmarks for materialized views.Tom Lane2014-03-06
| | | | | | | | | | We should allow this so that matviews can be referenced in UPDATE/DELETE statements in READ COMMITTED isolation level. The requirement for that is that a re-fetch by TID will see the same row version the query saw earlier, which is true of matviews, so there's no reason for the restriction. Per bug #9398. Michael Paquier, after a suggestion by me
* Remove the correct pgstat file on DROP DATABASEAlvaro Herrera2014-03-05
| | | | | | | | | | | | | | | | We were unlinking the permanent file, not the non-permanent one. But since the stat collector already unlinks all permanent files on startup, there was nothing for it to unlink. The non-permanent file remained in place, and was copied to the permanent directory on shutdown, so in effect no file was ever dropped. Backpatch to 9.3, where the issue was introduced by commit 187492b6c2e8. Before that, there were no per-database files and thus no file to drop on DROP DATABASE. Per report from Thom Brown. Author: Tomáš Vondra
* Do wal_level and hot standby checks when doing crash-then-archive recovery.Heikki Linnakangas2014-03-05
| | | | | | | | CheckRequiredParameterValues() should perform the checks if archive recovery was requested, even if we are going to perform crash recovery first. Reported by Kyotaro HORIGUCHI. Backpatch to 9.2, like the crash-then-archive recovery mode.
* Fix lastReplayedEndRecPtr calculation when starting from shutdown checkpoint.Heikki Linnakangas2014-03-05
| | | | | | | | | | | | | | | When entering crash recovery followed by archive recovery, and the latest checkpoint is a shutdown checkpoint, and there are no more WAL records to replay before transitioning from crash to archive recovery, we would not immediately allow read-only connections in hot standby mode even if we could. That's because when starting from a shutdown checkpoint, we set lastReplayedEndRecPtr incorrectly to the record before the checkpoint record, instead of the checkpoint record itself. We don't run the redo routine of the shutdown checkpoint record, but starting recovery from it goes through the same motions, so it should be considered as replayed. Reported by Kyotaro HORIGUCHI. All versions with hot standby are affected, so backpatch to 9.0.
* Error out on send failure in walsender loop.Heikki Linnakangas2014-03-04
| | | | | | | | | I changed the loop in 9.3 to use "goto send_failure" instead of "break" on errors, but I missed this one case. It was a relatively harmless bug: if the flush fails once it will most likely fail again as soon as we try to flush the output again. But it's a bug nevertheless. Report and fix by Andres Freund.
* Allow regex operations to be terminated early by query cancel requests.Tom Lane2014-03-01
| | | | | | | | | | | | | | | | | | | | | | | | | The regex code didn't have any provision for query cancel; which is unsurprising given its non-Postgres origin, but still problematic since some operations can take a long time. Introduce a callback function to check for a pending query cancel or session termination request, and call it in a couple of strategic spots where we can make the regex code exit with an error indicator. If we ever actually split out the regex code as a standalone library, some additional work will be needed to let the cancel callback function be specified externally to the library. But that's straightforward (certainly so by comparison to putting the locale-dependent character classification logic on a similar arms-length basis), and there seems no need to do it right now. A bigger issue is that there may be more places than these two where we need to check for cancels. We can always add more checks later, now that the infrastructure is in place. Since there are known examples of not-terribly-long regexes that can lock up a backend for a long time, back-patch to all supported branches. I have hopes of fixing the known performance problems later, but adding query cancel ability seems like a good idea even if they were all fixed.