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* Fix NOTIFY to cope with I/O problems, such as out-of-disk-space.Tom Lane2012-06-29
| | | | | | | | | | | | | The LISTEN/NOTIFY subsystem got confused if SimpleLruZeroPage failed, which would typically happen as a result of a write() failure while attempting to dump a dirty pg_notify page out of memory. Subsequently, all attempts to send more NOTIFY messages would fail with messages like "Could not read from file "pg_notify/nnnn" at offset nnnnn: Success". Only restarting the server would clear this condition. Per reports from Kevin Grittner and Christoph Berg. Back-patch to 9.0, where the problem was introduced during the LISTEN/NOTIFY rewrite.
* Improve pg_dump's dependency-sorting logic to enforce section dump order.Tom Lane2012-06-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As of 9.2, with the --section option, it is very important that the concept of "pre data", "data", and "post data" sections of the output be honored strictly; else a dump divided into separate sectional files might be unrestorable. However, the dependency-sorting logic knew nothing of sections and would happily select output orderings that didn't fit that structure. Doing so was mostly harmless before 9.2, but now we need to be sure it doesn't do that. To fix, create dummy objects representing the section boundaries and add dependencies between them and all the normal objects. (This might sound expensive but it seems to only add a percent or two to pg_dump's runtime.) This also fixes a problem introduced in 9.1 by the feature that allows incomplete GROUP BY lists when a primary key is given in GROUP BY. That means that views can depend on primary key constraints. Previously, pg_dump would deal with that by simply emitting the primary key constraint before the view definition (and hence before the data section of the output). That's bad enough for simple serial restores, where creating an index before the data is loaded works, but is undesirable for speed reasons. But it could lead to outright failure of parallel restores, as seen in bug #6699 from Joe Van Dyk. That happened because pg_restore would switch into parallel mode as soon as it reached the constraint, and then very possibly would try to emit the view definition before the primary key was committed (as a consequence of another bug that causes the view not to be correctly marked as depending on the constraint). Adding the section boundary constraints forces the dependency-sorting code to break the view into separate table and rule declarations, allowing the rule, and hence the primary key constraint it depends on, to revert to their intended location in the post-data section. This also somewhat accidentally works around the bogus-dependency-marking problem, because the rule will be correctly shown as depending on the constraint, so parallel pg_restore will now do the right thing. (We will fix the bogus-dependency problem for real in a separate patch, but that patch is not easily back-portable to 9.1, so the fact that this patch is enough to dodge the only known symptom is fortunate.) Back-patch to 9.1, except for the hunk that adds verification that the finished archive TOC list is in correct section order; the place where it was convenient to add that doesn't exist in 9.1.
* Fix memory leak in ARRAY(SELECT ...) subqueries.Tom Lane2012-06-21
| | | | | | | | | | | Repeated execution of an uncorrelated ARRAY_SUBLINK sub-select (which I think can only happen if the sub-select is embedded in a larger, correlated subquery) would leak memory for the duration of the query, due to not reclaiming the array generated in the previous execution. Per bug #6698 from Armando Miraglia. Diagnosis and fix idea by Heikki, patch itself by me. This has been like this all along, so back-patch to all supported versions.
* pg_dump: Fix verbosity level in LO progress messagesAlvaro Herrera2012-06-19
| | | | | | | | In passing, reword another instance of the same message that was gratuitously different. Author: Josh Kupershmidt after a bug report by Bosco Rama
* Update copyright year in forgotten placesPeter Eisentraut2012-06-19
| | | | found by Stefan Kaltenbrunner
* Prevent non-streaming replication connections from being selected sync slaveMagnus Hagander2012-06-11
| | | | | | | | | | | | This prevents a pg_basebackup backup session that just does a base backup (no xlog involved at all) from becoming the synchronous slave and thus blocking all access while it runs. Also fixes the problem when a higher priority slave shows up it would become the sync standby before it has reached the STREAMING state, by making sure we can only switch to a walsender that's actually STREAMING. Fujii Masao
* Fix bug in early startup of Hot Standby with subtransactions.Simon Riggs2012-06-08
| | | | | | | | | | When HS startup is deferred because of overflowed subtransactions, ensure that we re-initialize KnownAssignedXids for when both existing and incoming snapshots have non-zero qualifying xids. Fixes bug #6661 reported by Valentine Gogichashvili. Analysis and fix by Andres Freund
* Wake WALSender to reduce data loss at failover for async commit.Simon Riggs2012-06-07
| | | | | | | | | WALSender now woken up after each background flush by WALwriter, avoiding multi-second replication delay for an all-async commit workload. Replication delay reduced from 7s with default settings to 200ms, allowing significantly reduced data loss at failover. Andres Freund and Simon Riggs
* Backpatch error message fix from 81f6bbe8ade8c90f23f9286ca9ca726d3e0e310fMagnus Hagander2012-06-05
| | | | | | Without this, pg_basebackup doesn't tell you why it failed when for example there is a file in the data directory that the backend doesn't have permissions to read.
* Avoid early reuse of btree pages, causing incorrect query results.Simon Riggs2012-06-01
| | | | | | | | | | | | | When we allowed read-only transactions to skip assigning XIDs we introduced the possibility that a fully deleted btree page could be reused. This broke the index link sequence which could then lead to indexscans silently returning fewer rows than would have been correct. The actual incidence of silent errors from this is thought to be very low because of the exact workload required and locking pre-conditions. Fix is to remove pages only if index page opaque->btpo.xact precedes RecentGlobalXmin. Noah Misch, reviewed by Simon Riggs
* Stamp 9.1.4.REL9_1_4Tom Lane2012-05-31
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* Translation updatesPeter Eisentraut2012-05-31
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* Revert back-branch changes in behavior of age(xid).Tom Lane2012-05-31
| | | | | | | | Per discussion, it does not seem like a good idea to change the behavior of age(xid) in a minor release, even though the old definition causes the function to fail on hot standby slaves. Therefore, revert commit 5829387381d2e4edf84652bb5a712f6185860670 and follow-on commits in the back branches only.
* Update time zone data files to tzdata release 2012c.Tom Lane2012-05-31
| | | | | | DST law changes in Antarctica, Armenia, Chile, Cuba, Falkland Islands, Gaza, Haiti, Hebron, Morocco, Syria, Tokelau Islands. Historical corrections for Canada.
* Ignore SECURITY DEFINER and SET attributes for a PL's call handler.Tom Lane2012-05-30
| | | | | | | | | | | | | | | | | | | | | | It's not very sensible to set such attributes on a handler function; but if one were to do so, fmgr.c went into infinite recursion because it would call fmgr_security_definer instead of the handler function proper. There is no way for fmgr_security_definer to know that it ought to call the handler and not the original function referenced by the FmgrInfo's fn_oid, so it tries to do the latter, causing the whole process to start over again. Ordinarily such misconfiguration of a procedural language's handler could be written off as superuser error. However, because we allow non-superuser database owners to create procedural languages and the handler for such a language becomes owned by the database owner, it is possible for a database owner to crash the backend, which ideally shouldn't be possible without superuser privileges. In 9.2 and up we will adjust things so that the handler functions are always owned by superusers, but in existing branches this is a minor security fix. Problem noted by Noah Misch (after several of us had failed to detect it :-(). This is CVE-2012-2655.
* Expand the allowed range of timezone offsets to +/-15:59:59 from Greenwich.Tom Lane2012-05-30
| | | | | | | | | | | | | | | We used to only allow offsets less than +/-13 hours, then it was +/14, then it was +/-15. That's still not good enough though, as per today's bug report from Patric Bechtel. This time I actually looked through the Olson timezone database to find the largest offsets used anywhere. The winners are Asia/Manila, at -15:56:00 until 1844, and America/Metlakatla, at +15:13:42 until 1867. So we'd better allow offsets less than +/-16 hours. Given the history, we are way overdue to have some greppable #define symbols controlling this, so make some ... and also remove an obsolete comment that didn't get fixed the last time. Back-patch to all supported branches.
* Teach AbortOutOfAnyTransaction to clean up partially-started transactions.Tom Lane2012-05-28
| | | | | | | | | | | | AbortOutOfAnyTransaction failed to do anything if the state it saw on entry corresponded to failing partway through StartTransaction. I fixed AbortCurrentTransaction to cope with that case way back in commit 60b2444cc3ba037630c9b940c3c9ef01b954b87b, but evidently overlooked that AbortOutOfAnyTransaction should do likewise. Back-patch to all supported branches. It's not clear that this omission has any more-than-cosmetic consequences, but it's also not clear that it doesn't, so back-patching seems the least risky choice.
* Prevent synchronized scanning when systable_beginscan chooses a heapscan.Tom Lane2012-05-26
| | | | | | | | | | | | | | | The only interesting-for-performance case wherein we force heapscan here is when we're rebuilding the relcache init file, and the only such case that is likely to be examining a catalog big enough to be syncscanned is RelationBuildTupleDesc. But the early-exit optimization in that code gets broken if we start the scan at a random place within the catalog, so that allowing syncscan is actually a big deoptimization if pg_attribute is large (at least for the normal case where the rows for core system catalogs have never been changed since initdb). Hence, prevent syncscan here. Per my testing pursuant to complaints from Jeff Frost and Greg Sabino Mullane, though neither of them seem to have actually hit this specific problem. Back-patch to 8.3, where syncscan was introduced.
* Fix string truncation to be multibyte-aware in text_name and bpchar_name.Tom Lane2012-05-25
| | | | | | | | | | | Previously, casts to name could generate invalidly-encoded results. Also, make these functions match namein() more exactly, by consistently using palloc0() instead of ad-hoc zeroing code. Back-patch to all supported branches. Karl Schnaitter and Tom Lane
* Use binary search instead of brute-force scan in findNamespace().Tom Lane2012-05-25
| | | | | | | | | | | The previous coding presented a significant bottleneck when dumping databases containing many thousands of schemas, since the total time spent searching would increase roughly as O(N^2) in the number of objects. Noted by Jeff Janes, though I rewrote his proposed patch to use the existing findObjectByOid infrastructure. Since this is a longstanding performance bug, backpatch to all supported versions.
* Ensure that seqscans check for interrupts at least once per page.Tom Lane2012-05-22
| | | | | | | | | | | | | If a seqscan encounters many consecutive pages containing only dead tuples, it can remain in the loop in heapgettup for a long time, and there was no CHECK_FOR_INTERRUPTS anywhere in that loop. This meant there were real-world situations where a query would be effectively uncancelable for long stretches. Add a check placed to occur once per page, which should be enough to provide reasonable response time without adding any measurable overhead. Report and patch by Merlin Moncure (though I tweaked it a bit). Back-patch to all supported branches.
* Fix error message for COMMENT/SECURITY LABEL ON COLUMN xxx IS 'yyy'Robert Haas2012-05-22
| | | | | | | | When the column name is an unqualified name, rather than table.column, the error message complains about too many dotted names, which is wrong. Report by Peter Eisentraut based on examination of the sepgsql regression test output, but the problem also affects COMMENT. New wording as suggested by Tom Lane.
* Move postmaster's RemovePgTempFiles call to a less randomly chosen place.Tom Lane2012-05-21
| | | | | | | | | | | | | | | | | | There is no reason to do this as early as possible in postmaster startup, and good reason not to do it until we have completely created the postmaster's lock file, namely that it might contribute to pg_ctl thinking that postmaster startup has timed out. (This would require a rather unusual amount of time to be spent scanning temp file directories, but we have at least one field report of it happening reproducibly.) Back-patch to 9.1. Before that, pg_ctl didn't wait for additional info to be added to the lock file, so it wasn't a problem. Note that this is not a complete fix to the slow-start issue in 9.1, because we still had identify_system_timezone being run during postmaster start in 9.1. But that's at least a reasonably well-defined delay, with an easy workaround if needed, whereas the temp-files scan is not so predictable and cannot be avoided.
* Fix bug in to_tsquery().Heikki Linnakangas2012-05-15
| | | | | We were using memcpy() to copy to a possibly overlapping memory region, which is a no-no. Use memmove() instead.
* Fix DROP TABLESPACE to unlink symlink when directory is not there.Tom Lane2012-05-13
| | | | | | | | | | | | | | | | | | | | | If the tablespace directory is missing entirely, we allow DROP TABLESPACE to go through, on the grounds that it should be possible to clean up the catalog entry in such a situation. However, we forgot that the pg_tblspc symlink might still be there. We should try to remove the symlink too (but not fail if it's no longer there), since not doing so can lead to weird behavior subsequently, as per report from Michael Nolan. There was some discussion of adding dependency links to prevent DROP TABLESPACE when the catalogs still contain references to the tablespace. That might be worth doing too, but it's an orthogonal question, and in any case wouldn't be back-patchable. Back-patch to 9.0, which is as far back as the logic looks like this. We could possibly do something similar in 8.x, but given the lack of reports I'm not sure it's worth the trouble, and anyway the case could not arise in the form the logic is meant to cover (namely, a post-DROP transaction rollback having resurrected the pg_tablespace entry after some or all of the filesystem infrastructure is gone).
* Ensure backwards compatibility for GetStableLatestTransactionId()Simon Riggs2012-05-12
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* Prevent loss of init fork when truncating an unlogged table.Robert Haas2012-05-11
| | | | Fixes bug #6635, reported by Akira Kurosawa.
* Remove extraneous #include "storage/proc.h"Simon Riggs2012-05-11
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* Ensure age() returns a stable value rather than the latest valueSimon Riggs2012-05-11
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* On GiST page split, release the locks on child pages before recursing up.Heikki Linnakangas2012-05-11
| | | | | | | | | | | | | | | | | | When inserting the downlinks for a split gist page, we used hold the locks on the child pages until the insertion into the parent - and recursively its parent if it had to be split too - were all completed. Change that so that the locks on child pages are released after the insertion in the immediate parent is done, before recursing further up the tree. This reduces the number of lwlocks that are held simultaneously. Holding many locks is bad for concurrency, and in extreme cases you can even hit the limit of 100 simultaneously held lwlocks in a backend. If you're really unlucky, you can hit the limit while in a critical section, which brings down the whole system. This fixes bug #6629 reported by Tom Forbes. Backpatch to 9.1. The page splitting code was rewritten in 9.1, and the old code did not have this problem.
* Fix Windows implementation of PGSemaphoreLock.Tom Lane2012-05-10
| | | | | | | | | | | | | The original coding failed to reset ImmediateInterruptOK before returning, which would potentially allow a subsequent query-cancel interrupt to be accepted at an unsafe point. This is a really nasty bug since it's so hard to predict the consequences, but they could be unpleasant. Also, ensure that signal handlers are serviced before this function returns, even if the semaphore is already set. This should make the behavior more like Unix. Back-patch to all supported versions.
* Only attempt to show collations on servers >= 9.1.Magnus Hagander2012-05-10
| | | | | | Show a proper error message instead of a SQL error. Josh Kupershmidt
* PL/pgSQL RETURN NEXT was leaking converted tuples, causingJoe Conway2012-05-09
| | | | | | out of memory when looping through large numbers of rows. Flag the converted tuples to be freed. Complaint and patch by Joe.
* Avoid xid error from age() function when run on Hot StandbySimon Riggs2012-05-09
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* Overdue code review for transaction-level advisory locks patch.Tom Lane2012-05-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 62c7bd31c8878dd45c9b9b2429ab7a12103f3590 had assorted problems, most visibly that it broke PREPARE TRANSACTION in the presence of session-level advisory locks (which should be ignored by PREPARE), as per a recent complaint from Stephen Rees. More abstractly, the patch made the LockMethodData.transactional flag not merely useless but outright dangerous, because in point of fact that flag no longer tells you anything at all about whether a lock is held transactionally. This fix therefore removes that flag altogether. We now rely entirely on the convention already in use in lock.c that transactional lock holds must be owned by some ResourceOwner, while session holds are never so owned. Setting the locallock struct's owner link to NULL thus denotes a session hold, and there is no redundant marker for that. PREPARE TRANSACTION now works again when there are session-level advisory locks, and it is also able to transfer transactional advisory locks to the prepared transaction, but for implementation reasons it throws an error if we hold both types of lock on a single lockable object. Perhaps it will be worth improving that someday. Assorted other minor cleanup and documentation editing, as well. Back-patch to 9.1, except that in the 9.1 branch I did not remove the LockMethodData.transactional flag for fear of causing an ABI break for any external code that might be examining those structs.
* Fix printing of whole-row Vars at top level of a SELECT targetlist.Tom Lane2012-04-27
| | | | | | | | | | | | | | | | | | | | | Normally whole-row Vars are printed as "tabname.*". However, that does not work at top level of a targetlist, because per SQL standard the parser will think that the "*" should result in column-by-column expansion; which is not at all what a whole-row Var implies. We used to just print the table name in such cases, which works most of the time; but it fails if the table name matches a column name available anywhere in the FROM clause. This could lead for instance to a view being interpreted differently after dump and reload. Adding parentheses doesn't fix it, but there is a reasonably simple kluge we can use instead: attach a no-op cast, so that the "*" isn't syntactically at top level anymore. This makes the printing of such whole-row Vars a lot more consistent with other Vars, and may indeed fix more cases than just the reported one; I'm suspicious that cases involving schema qualification probably didn't work properly before, either. Per bug report and fix proposal from Abbas Butt, though this patch is quite different in detail from his. Back-patch to all supported versions.
* Fix syslogger's rotation disable/re-enable logic.Tom Lane2012-04-27
| | | | | | | | | | | | | | | | | | If it fails to open a new log file, the syslogger assumes there's something wrong with its parameters (such as log_directory), and stops attempting automatic time-based or size-based log file rotations. Sending it SIGHUP is supposed to start that up again. However, the original coding for that was really bogus, involving clobbering a couple of GUC variables and hoping that SIGHUP processing would restore them. Get rid of that technique in favor of maintaining a separate flag showing we've turned rotation off. Per report from Mark Kirkwood. Also, the syslogger will automatically attempt to create the log_directory directory if it doesn't exist, but that was only happening at startup. For consistency and ease of use, it should do the same whenever the value of log_directory is changed by SIGHUP. Back-patch to all supported branches.
* PL/Python: Accept strings in functions returning composite typesPeter Eisentraut2012-04-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before 9.1, PL/Python functions returning composite types could return a string and it would be parsed using record_in. The 9.1 changes made PL/Python only expect dictionaries, tuples, or objects supporting getattr as output of composite functions, resulting in a regression and a confusing error message, as the strings were interpreted as sequences and the code for transforming lists to database tuples was used. Fix this by treating strings separately as before, before checking for the other types. The reason why it's important to support string to database tuple conversion is that trigger functions on tables with composite columns get the composite row passed in as a string (from record_out). Without supporting converting this back using record_in, this makes it impossible to implement pass-through behavior for these columns, as PL/Python no longer accepts strings for composite values. A better solution would be to fix the code that transforms composite inputs into Python objects to produce dictionaries that would then be correctly interpreted by the Python->PostgreSQL counterpart code. But that would be too invasive to backpatch to 9.1, and it is too late in the 9.2 cycle to attempt it. It should be revisited in the future, though. Reported as bug #6559 by Kirill Simonov. Jan UrbaƄski
* Fix planner's handling of RETURNING lists in writable CTEs.Tom Lane2012-04-25
| | | | | | | | | | | | | | | | | | | | | | | | setrefs.c failed to do "rtoffset" adjustment of Vars in RETURNING lists, which meant they were left with the wrong varnos when the RETURNING list was in a subquery. That was never possible before writable CTEs, of course, but now it's broken. The executor fails to notice any problem because ExecEvalVar just references the ecxt_scantuple for any normal varno; but EXPLAIN breaks when the varno is wrong, as illustrated in a recent complaint from Bartosz Dmytrak. Since the eventual rtoffset of the subquery is not known at the time we are preparing its plan node, the previous scheme of executing set_returning_clause_references() at that time cannot handle this adjustment. Fortunately, it turns out that we don't really need to do it that way, because all the needed information is available during normal setrefs.c execution; we just have to dig it out of the ModifyTable node. So, do that, and get rid of the kluge of early setrefs processing of RETURNING lists. (This is a little bit of a cheat in the case of inherited UPDATE/DELETE, because we are not passing a "root" struct that corresponds exactly to what the subplan was built with. But that doesn't matter, and anyway this is less ugly than early setrefs processing was.) Back-patch to 9.1, where the problem became possible to hit.
* Fix edge-case behavior of pg_next_dst_boundary().Tom Lane2012-04-25
| | | | | | | | | | | | | | | | | | | Due to rather sloppy thinking (on my part, I'm afraid) about the appropriate behavior for boundary conditions, pg_next_dst_boundary() gave undefined, platform-dependent results when the input time is exactly the last recorded DST transition time for the specified time zone, as a result of fetching values one past the end of its data arrays. Change its specification to be that it always finds the next DST boundary *after* the input time, and adjust code to match that. The sole existing caller, DetermineTimeZoneOffset, doesn't actually care about this distinction, since it always uses a probe time earlier than the instant that it does care about. So it seemed best to me to change the API to make the result=1 and result=0 cases more consistent, specifically to ensure that the "before" outputs always describe the state at the given time, rather than hacking the code to obey the previous API comment exactly. Per bug #6605 from Sergey Burladyan. Back-patch to all supported versions.
* PL/Python: Improve error messagesPeter Eisentraut2012-04-25
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* Revert recent commit re positional arguments.Andrew Dunstan2012-04-18
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* Fix copyfuncs/equalfuncs support for ReassignOwnedStmt.Robert Haas2012-04-18
| | | | Noah Misch
* Don't override arguments set via options with positional arguments.Andrew Dunstan2012-04-17
| | | | | | | | | A number of utility programs were rather careless about paremeters that can be set via both an option argument and a positional argument. This leads to results which can violate the Principal Of Least Astonishment. These changes refuse to use positional arguments to override settings that have been made via positional arguments. The changes are backpatched to all live branches.
* Don't wait for the commit record to be replicated if we wrote no WAL.Heikki Linnakangas2012-04-17
| | | | | | | | When using synchronous replication, we waited for the commit record to be replicated, but if we our transaction didn't write any other WAL records, that's not required because we don't even flush the WAL locally to disk in that case. This lead to long waits when committing a transaction that only modified a temporary table. Bug spotted by Thom Brown.
* Clamp indexscan filter condition cost estimate to be not less than zero.Tom Lane2012-04-11
| | | | | | | | | | | | | | | | | cost_index tries to estimate the per-tuple costs of evaluating filter conditions (a/k/a qpquals) by subtracting the estimated cost of the indexqual conditions from that of the baserestrictinfo conditions. This is correct so long as the indexquals list is a subset of the baserestrictinfo list. However, in the presence of derived indexable conditions it's completely wrong, leading to bogus or even negative scan cost estimates, as seen for example in bug #6579 from Istvan Endredy. In practice the problem isn't severe except in the specific case of a LIKE optimization on a functional index containing a very expensive function. A proper fix for this might change cost estimates by more than people would like for stable branches, so in the back branches let's just clamp the cost difference to be not less than zero. That will at least prevent completely insane behavior, while not changing the results normally.
* Ignore missing schemas during non-interactive assignment of search_path.Tom Lane2012-04-11
| | | | | | This aligns 9.1's behavior with that of older branches. HEAD is now even laxer, ignoring missing schemas all the time, but that seems like too big a change for a released branch. Per complaint from Robert Haas.
* Fix an Assert that turns out to be reachable after all.Tom Lane2012-04-09
| | | | | | | | | estimate_num_groups() gets unhappy with create table empty(); select * from empty except select * from empty e2; I can't see any actual use-case for such a query (and the table is illegal per SQL spec), but it seems like a good idea that it not cause an assert failure.
* set_stack_base() no longer needs to be called in PostgresMain.Heikki Linnakangas2012-04-08
| | | | | | This was a thinko in previous commit. Now that stack base pointer is now set in PostmasterMain and SubPostmasterMain, it doesn't need to be set in PostgresMain anymore.
* Do stack-depth checking in all postmaster children.Heikki Linnakangas2012-04-08
| | | | | | | | | | | | | | | | | | | We used to only initialize the stack base pointer when starting up a regular backend, not in other processes. In particular, autovacuum workers can run arbitrary user code, and without stack-depth checking, infinite recursion in e.g an index expression will bring down the whole cluster. The comment about PL/Java using set_stack_base() is not yet true. As the code stands, PL/java still modifies the stack_base_ptr variable directly. However, it's been discussed in the PL/Java mailing list that it should be changed to use the function, because PL/Java is currently oblivious to the register stack used on Itanium. There's another issues with PL/Java, namely that the stack base pointer it sets is not really the base of the stack, it could be something close to the bottom of the stack. That's a separate issue that might need some further changes to this code, but that's a different story. Backpatch to all supported releases.