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* Add recursion depth protection to LIKE matching.Tom Lane2015-10-02
| | | | | Since MatchText() recurses, it could in principle be driven to stack overflow, although quite a long pattern would be needed.
* Add recursion depth protections to regular expression matching.Tom Lane2015-10-02
| | | | | | | | | | | | | | | Some of the functions in regex compilation and execution recurse, and therefore could in principle be driven to stack overflow. The Tcl crew has seen this happen in practice in duptraverse(), though their fix was to put in a hard-wired limit on the number of recursive levels, which is not too appetizing --- fortunately, we have enough infrastructure to check the actually available stack. Greg Stark has also seen it in other places while fuzz testing on a machine with limited stack space. Let's put guards in to prevent crashes in all these places. Since the regex code would leak memory if we simply threw elog(ERROR), we have to introduce an API that checks for stack depth without throwing such an error. Fortunately that's not difficult.
* Fix potential infinite loop in regular expression execution.Tom Lane2015-10-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In cfindloop(), if the initial call to shortest() reports that a zero-length match is possible at the current search start point, but then it is unable to construct any actual match to that, it'll just loop around with the same start point, and thus make no progress. We need to force the start point to be advanced. This is safe because the loop over "begin" points has already tried and failed to match starting at "close", so there is surely no need to try that again. This bug was introduced in commit e2bd904955e2221eddf01110b1f25002de2aaa83, wherein we allowed continued searching after we'd run out of match possibilities, but evidently failed to think hard enough about exactly where we needed to search next. Because of the way this code works, such a match failure is only possible in the presence of backrefs --- otherwise, shortest()'s judgment that a match is possible should always be correct. That probably explains how come the bug has escaped detection for several years. The actual fix is a one-liner, but I took the trouble to add/improve some comments related to the loop logic. After fixing that, the submitted test case "()*\1" didn't loop anymore. But it reported failure, though it seems like it ought to match a zero-length string; both Tcl and Perl think it does. That seems to be from overenthusiastic optimization on my part when I rewrote the iteration match logic in commit 173e29aa5deefd9e71c183583ba37805c8102a72: we can't just "declare victory" for a zero-length match without bothering to set match data for capturing parens inside the iterator node. Per fuzz testing by Greg Stark. The first part of this is a bug in all supported branches, and the second part is a bug since 9.2 where the iteration rewrite happened.
* Add some more query-cancel checks to regular expression matching.Tom Lane2015-10-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 9662143f0c35d64d7042fbeaf879df8f0b54be32 added infrastructure to allow regular-expression operations to be terminated early in the event of SIGINT etc. However, fuzz testing by Greg Stark disclosed that there are still cases where regex compilation could run for a long time without noticing a cancel request. Specifically, the fixempties() phase never adds new states, only new arcs, so it doesn't hit the cancel check I'd put in newstate(). Add one to newarc() as well to cover that. Some experimentation of my own found that regex execution could also run for a long time despite a pending cancel. We'd put a high-level cancel check into cdissect(), but there was none inside the core text-matching routines longest() and shortest(). Ordinarily those inner loops are very very fast ... but in the presence of lookahead constraints, not so much. As a compromise, stick a cancel check into the stateset cache-miss function, which is enough to guarantee a cancel check at least once per lookahead constraint test. Making this work required more attention to error handling throughout the regex executor. Henry Spencer had apparently originally intended longest() and shortest() to be incapable of incurring errors while running, so neither they nor their subroutines had well-defined error reporting behaviors. However, that was already broken by the lookahead constraint feature, since lacon() can surely suffer an out-of-memory failure --- which, in the code as it stood, might never be reported to the user at all, but just silently be treated as a non-match of the lookahead constraint. Normalize all that by inserting explicit error tests as needed. I took the opportunity to add some more comments to the code, too. Back-patch to all supported branches, like the previous patch.
* Don't disable commit_ts in standby if enabled locallyAlvaro Herrera2015-10-02
| | | | Bug noticed by Fujii Masao
* Fix message punctuation according to style guidePeter Eisentraut2015-10-01
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* Fix commit_ts for standbyAlvaro Herrera2015-10-01
| | | | | | | | | | | | | | | | | | | | | | | Module initialization was still not completely correct after commit 6b61955135e9, per crash report from Takashi Ohnishi. To fix, instead of trying to monkey around with the value of the GUC setting directly, add a separate boolean flag that enables the feature on a standby, but only for the startup (recovery) process, when it sees that its master server has the feature enabled. Discussion: http://www.postgresql.org/message-id/ca44c6c7f9314868bdc521aea4f77cbf@MP-MSGSS-MBX004.msg.nttdata.co.jp Also change the deactivation routine to delete all segment files rather than leaving the last one around. (This doesn't need separate WAL-logging, because on recovery we execute the same deactivation routine anyway.) In passing, clean up the code structure somewhat, particularly so that xlog.c doesn't know so much about when to activate/deactivate the feature. Thanks to Fujii Masao for testing and Petr Jelínek for off-list discussion. Back-patch to 9.5, where commit_ts was introduced.
* Fix documentation error in commit 8703059c6b55c427100e00a09f66534b6ccbfaa1.Tom Lane2015-10-01
| | | | Etsuro Fujita spotted a thinko in the README commentary.
* Fix readfuncs/outfuncs problems in last night's Gather patch.Robert Haas2015-10-01
| | | | KaiGai Kohei, with one correction by me.
* Fix errors in commit a04bb65f70dafdf462e0478ad19e6de56df89bfc.Tom Lane2015-09-30
| | | | Not a lot of commentary needed here really.
* Improve LISTEN startup time when there are many unread notifications.Tom Lane2015-09-30
| | | | | | | | | | | | | | | | If some existing listener is far behind, incoming new listener sessions would start from that session's read pointer and then need to advance over many already-committed notification messages, which they have no interest in. This was expensive in itself and also thrashed the pg_notify SLRU buffers a lot more than necessary. We can improve matters considerably in typical scenarios, without much added cost, by starting from the furthest-ahead read pointer, not the furthest-behind one. We do have to consider only sessions in our own database when doing this, which requires an extra field in the data structure, but that's a pretty small cost. Back-patch to 9.0 where the current LISTEN/NOTIFY logic was introduced. Matt Newell, slightly adjusted by me
* Add a Gather executor node.Robert Haas2015-09-30
| | | | | | | | | | | | | | | | | | | | | | | | A Gather executor node runs any number of copies of a plan in an equal number of workers and merges all of the results into a single tuple stream. It can also run the plan itself, if the workers are unavailable or haven't started up yet. It is intended to work with the Partial Seq Scan node which will be added in future commits. It could also be used to implement parallel query of a different sort by itself, without help from Partial Seq Scan, if the single_copy mode is used. In that mode, a worker executes the plan, and the parallel leader does not, merely collecting the worker's results. So, a Gather node could be inserted into a plan to split the execution of that plan across two processes. Nested Gather nodes aren't currently supported, but we might want to add support for that in the future. There's nothing in the planner to actually generate Gather nodes yet, so it's not quite time to break out the champagne. But we're getting close. Amit Kapila. Some designs suggestions were provided by me, and I also reviewed the patch. Single-copy mode, documentation, and other minor changes also by me.
* Don't dump core when destroying an unused ParallelContext.Robert Haas2015-09-30
| | | | | | If a transaction or subtransaction creates a ParallelContext but ends without calling InitializeParallelDSM, the previous code would seg fault. Fix that.
* Include policies based on ACLs neededStephen Frost2015-09-30
| | | | | | | | | | | | | | | | | | | | | | | When considering which policies should be included, rather than look at individual bits of the query (eg: if a RETURNING clause exists, or if a WHERE clause exists which is referencing the table, or if it's a FOR SHARE/UPDATE query), consider any case where we've determined the user needs SELECT rights on the relation while doing an UPDATE or DELETE to be a case where we apply SELECT policies, and any case where we've deteremind that the user needs UPDATE rights on the relation while doing a SELECT to be a case where we apply UPDATE policies. This simplifies the logic and addresses concerns that a user could use UPDATE or DELETE with a WHERE clauses to determine if rows exist, or they could use SELECT .. FOR UPDATE to lock rows which they are not actually allowed to modify through UPDATE policies. Use list_append_unique() to avoid adding the same quals multiple times, as, on balance, the cost of checking when adding the quals will almost always be cheaper than keeping them and doing busywork for each tuple during execution. Back-patch to 9.5 where RLS was added.
* Small improvements in comments in async.c.Tom Lane2015-09-29
| | | | | | | | | We seem to have lost a line somewhere along the way in the comment block that discusses async.c's locks, because it suddenly refers to "both locks" without previously having mentioned more than one. Add a sentence to make that read more sanely. Also, refer to the "pos of the slowest backend" not the "tail of the slowest backend", since we have no per-backend value called "tail".
* Code review for transaction commit timestampsAlvaro Herrera2015-09-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | There are three main changes here: 1. No longer cause a start failure in a standby if the feature is disabled in postgresql.conf but enabled in the master. This reverts one part of commit 4f3924d9cd43; what we keep is the ability of the standby to activate/deactivate the module (which includes creating and removing segments as appropriate) during replay of such actions in the master. 2. Replay WAL records affecting commitTS even if the feature is disabled. This means the standby will always have the same state as the master after replay. 3. Have COMMIT PREPARE record the transaction commit time as well. We were previously only applying it in the normal transaction commit path. Author: Petr Jelínek Discussion: http://www.postgresql.org/message-id/CAHGQGwHereDzzzmfxEBYcVQu3oZv6vZcgu1TPeERWbDc+gQ06g@mail.gmail.com Discussion: http://www.postgresql.org/message-id/CAHGQGwFuzfO4JscM9LCAmCDCxp_MfLvN4QdB+xWsS-FijbjTYQ@mail.gmail.com Additionally, I cleaned up nearby code related to replication origins, which I found a bit hard to follow, and fixed a couple of typos. Backpatch to 9.5, where this code was introduced. Per bug reports from Fujii Masao and subsequent discussion.
* Comment update for join pushdown.Robert Haas2015-09-29
| | | | Etsuro Fujita
* Parallel executor support.Robert Haas2015-09-28
| | | | | | | | | | | | | This code provides infrastructure for a parallel leader to start up parallel workers to execute subtrees of the plan tree being executed in the master. User-supplied parameters from ParamListInfo are passed down, but PARAM_EXEC parameters are not. Various other constructs, such as initplans, subplans, and CTEs, are also not currently shared. Nevertheless, there's enough here to support a basic implementation of parallel query, and we can lift some of the current restrictions as needed. Amit Kapila and Robert Haas
* Fix "sesssion" typoAlvaro Herrera2015-09-28
| | | | | | | It was introduced alongside replication origins, by commit 5aa2350426c, so backpatch to 9.5. Pointed out by Fujii Masao
* COPY: use pg_plan_query() instead of planner()Alvaro Herrera2015-09-28
| | | | | While at it, trim the includes list in copy.c. The planner headers cannot be removed, but there are a few others that are not of any use.
* Fix ON CONFLICT DO UPDATE for tables with oids.Andres Freund2015-09-28
| | | | | | | | | | When taking the UPDATE path in an INSERT .. ON CONFLICT .. UPDATE tables with oids were not supported. The tuple generated by the update target list was projected without space for an oid - a simple oversight. Reported-By: Peter Geoghegan Author: Andres Freund Backpatch: 9.5, where ON CONFLICT was introduced
* Use LOCKBIT_ON() instead of a bit shift in a few places.Robert Haas2015-09-28
| | | | | | | We do this mostly everywhere, so it seems just as well to do it here, too. Thomas Munro
* Remove legacy multixact truncation support.Andres Freund2015-09-26
| | | | | | | | | | | | | In 9.5 and master there is no need to support legacy truncation. This is just committed separately to make it easier to backpatch the WAL logged multixact truncation to 9.3 and 9.4 if we later decide to do so. I bumped master's magic from 0xD086 to 0xD088 and 9.5's from 0xD085 to 0xD087 to avoid 9.5 reusing a value that has been in use on master while keeping the numbers increasing between major versions. Discussion: 20150621192409.GA4797@alap3.anarazel.de Backpatch: 9.5
* Rework the way multixact truncations work.Andres Freund2015-09-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The fact that multixact truncations are not WAL logged has caused a fair share of problems. Amongst others it requires to do computations during recovery while the database is not in a consistent state, delaying truncations till checkpoints, and handling members being truncated, but offset not. We tried to put bandaids on lots of these issues over the last years, but it seems time to change course. Thus this patch introduces WAL logging for multixact truncations. This allows: 1) to perform the truncation directly during VACUUM, instead of delaying it to the checkpoint. 2) to avoid looking at the offsets SLRU for truncation during recovery, we can just use the master's values. 3) simplify a fair amount of logic to keep in memory limits straight, this has gotten much easier During the course of fixing this a bunch of additional bugs had to be fixed: 1) Data was not purged from memory the member's SLRU before deleting segments. This happened to be hard or impossible to hit due to the interlock between checkpoints and truncation. 2) find_multixact_start() relied on SimpleLruDoesPhysicalPageExist - but that doesn't work for offsets that haven't yet been flushed to disk. Add code to flush the SLRUs to fix. Not pretty, but it feels slightly safer to only make decisions based on actual on-disk state. 3) find_multixact_start() could be called concurrently with a truncation and thus fail. Via SetOffsetVacuumLimit() that could lead to a round of emergency vacuuming. The problem remains in pg_get_multixact_members(), but that's quite harmless. For now this is going to only get applied to 9.5+, leaving the issues in the older branches in place. It is quite possible that we need to backpatch at a later point though. For the case this gets backpatched we need to handle that an updated standby may be replaying WAL from a not-yet upgraded primary. We have to recognize that situation and use "old style" truncation (i.e. looking at the SLRUs) during WAL replay. In contrast to before, this now happens in the startup process, when replaying a checkpoint record, instead of the checkpointer. Doing truncation in the restartpoint is incorrect, they can happen much later than the original checkpoint, thereby leading to wraparound. To avoid "multixact_redo: unknown op code 48" errors standbys would have to be upgraded before primaries. A later patch will bump the WAL page magic, and remove the legacy truncation codepaths. Legacy truncation support is just included to make a possible future backpatch easier. Discussion: 20150621192409.GA4797@alap3.anarazel.de Reviewed-By: Robert Haas, Alvaro Herrera, Thomas Munro Backpatch: 9.5 for now
* Second try at fixing O(N^2) problem in foreign key references.Tom Lane2015-09-25
| | | | | | | | | | | | | | | | | | | | | This replaces ill-fated commit 5ddc72887a012f6a8b85707ef27d85c274faf53d, which was reverted because it broke active uses of FK cache entries. In this patch, we still do nothing more to invalidatable cache entries than mark them as needing revalidation, so we won't break active uses. To keep down the overhead of InvalidateConstraintCacheCallBack(), keep a list of just the currently-valid cache entries. (The entries are large enough that some added space for list links doesn't seem like a big problem.) This would still be O(N^2) when there are many valid entries, though, so when the list gets too long, just force the "sinval reset" behavior to remove everything from the list. I set the threshold at 1000 entries, somewhat arbitrarily. Possibly that could be fine-tuned later. Another item for future study is whether it's worth adding reference counting so that we could safely remove invalidated entries. As-is, problem cases are likely to end up with large and mostly invalid FK caches. Like the previous attempt, backpatch to 9.3. Jan Wieck and Tom Lane
* Allow planner to use expression-index stats for function calls in WHERE.Tom Lane2015-09-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously, a function call appearing at the top level of WHERE had a hard-wired selectivity estimate of 0.3333333, a kludge conveniently dated in the source code itself to July 1992. The expectation at the time was that somebody would soon implement estimator support functions analogous to those for operators; but no such code has appeared, nor does it seem likely to in the near future. We do have an alternative solution though, at least for immutable functions on single relations: creating an expression index on the function call will allow ANALYZE to gather stats about the function's selectivity. But the code in clause_selectivity() failed to make use of such data even if it exists. Refactor so that that will happen. I chose to make it try this technique for any clause type for which clause_selectivity() doesn't have a special case, not just functions. To avoid adding unnecessary overhead in the common case where we don't learn anything new, make selfuncs.c provide an API that hooks directly to examine_variable() and then var_eq_const(), rather than the previous coding which laboriously constructed an OpExpr only so that it could be expensively deconstructed again. I preserved the behavior that the default estimate for a function call is 0.3333333. (For any other expression node type, it's 0.5, as before.) I had originally thought to make the default be 0.5 across the board, but changing a default estimate that's survived for twenty-three years seems like something not to do without a lot more testing than I care to put into it right now. Per a complaint from Jehan-Guillaume de Rorthais. Back-patch into 9.5, but not further, at least for the moment.
* Don't zero opfuncid when reading nodes.Robert Haas2015-09-24
| | | | | | | | | | | | | | The comments here stated that this was just in case we ever had an ALTER OPERATOR command that could remap an operator to a different function. But those comments have been here for a long time, and no such command has come about. In the absence of such a feature, forcing the pg_proc OID to be looked up again each time we reread a stored rule or similar is just a waste of cycles. Moreover, parallel query needs a way to reread the exact same node tree that was written out, not one that has been slightly stomped on. So just get rid of this for now. Per discussion with Tom Lane.
* Lower *_freeze_max_age minimum values.Andres Freund2015-09-24
| | | | | | | | | | | | | | | | | | The old minimum values are rather large, making it time consuming to test related behaviour. Additionally the current limits, especially for multixacts, can be problematic in space-constrained systems. 10000000 multixacts can contain a lot of members. Since there's no good reason for the current limits, lower them a good bit. Setting them to 0 would be a bad idea, triggering endless vacuums, so still retain a limit. While at it fix autovacuum_multixact_freeze_max_age to refer to multixact.c instead of varsup.c. Reviewed-By: Robert Haas Discussion: CA+TgmoYmQPHcrc3GSs7vwvrbTkbcGD9Gik=OztbDGGrovkkEzQ@mail.gmail.com Backpatch: back to 9.0 (in parts)
* Make ANALYZE compute basic statistics even for types with no "=" operator.Tom Lane2015-09-23
| | | | | | | | | | | | | | | | | Previously, ANALYZE simply ignored columns of datatypes that have neither a btree nor hash opclass (which means they have no recognized equality operator). Without a notion of equality, we can't identify most-common values nor estimate the number of distinct values. But we can still count nulls and compute the average physical column width, and those stats might be of value. Moreover there are some tools out there that don't work so well if rows are missing from pg_statistic. So let's add suitable logic for this case. While this is arguably a bug fix, it also has the potential to change query plans, and the gain seems not worth taking a risk of that in stable branches. So back-patch into 9.5 but not further. Oleksandr Shulgin, rewritten a bit by me.
* Add readfuncs.c support for plan nodes.Robert Haas2015-09-23
| | | | | | | | | | | | | | | | For parallel query, we need to be able to pass a Plan to a worker, so that it knows what it's supposed to do. We could invent our own way of serializing plans for that purpose, but piggybacking on the existing node infrastructure seems like a much better idea. Initially, we'll probably only support a limited number of nodes within parallel workers, but this commit adds support for everything in plannodes.h except CustomScan, because doing it all at once seems easier than doing it piecemeal, and it makes testing this code easier, too. CustomScan is excluded because making that work requires a larger rework of that facility. Amit Kapila, reviewed and slightly revised by me.
* Print a MergeJoin's mergeNullsFirst array as bool, not int.Robert Haas2015-09-23
| | | | | | | | | It's declared as being an array of bool, but it's printed differently from the way bool and arrays of bool are handled elsewhere. Patch by Amit Kapila. Anomaly noted independently by Amit Kapila and KaiGai Kohei.
* Allow autoanalyze to add pages deleted from pending list to FSMTeodor Sigaev2015-09-23
| | | | | | | | | | | | Commit e95680832854cf300e64c10de9cc2f586df558e8 introduces adding pages to FSM for ordinary insert, but autoanalyze was able just cleanup pending list without adding to FSM. Also fix double call of IndexFreeSpaceMapVacuum() during ginvacuumcleanup() Report from Fujii Masao Patch by me Review by Jeff Janes
* Teach planstate_tree_walker about custom scans.Robert Haas2015-09-22
| | | | | | | | This logic was missing from ExplainPreScanNode, from which I derived planstate_tree_walker. But it shouldn't be missing, especially not from a generic walker function, so add it. KaiGai Kohei
* Correct value of LW_SHARED_MASK.Andres Freund2015-09-22
| | | | | | | | | The previous wrong value lead to wrong LOCK_DEBUG output, never showing any shared lock holders. Reported-By: Alexander Korotkov Discussion: CAPpHfdsPmWqz9FB0AnxJrwp1=KLF0n=-iB+QvR0Q8GSmpFVdUQ@mail.gmail.com Backpatch: 9.5, where the bug was introduced.
* Fix possible internal overflow in numeric multiplication.Tom Lane2015-09-21
| | | | | | | | | | | | | mul_var() postpones propagating carries until it risks overflow in its internal digit array. However, the logic failed to account for the possibility of overflow in the carry propagation step, allowing wrong results to be generated in corner cases. We must slightly reduce the when-to-propagate-carries threshold to avoid that. Discovered and fixed by Dean Rasheed, with small adjustments by me. This has been wrong since commit d72f6c75038d8d37e64a29a04b911f728044d83b, so back-patch to all supported branches.
* Remove the SECURITY_ROW_LEVEL_DISABLED security context bit.Noah Misch2015-09-20
| | | | | | | | | | This commit's parent made superfluous the bit's sole usage. Referential integrity checks have long run as the subject table's owner, and that now implies RLS bypass. Safe use of the bit was tricky, requiring strict control over the SQL expressions evaluating therein. Back-patch to 9.5, where the bit was introduced. Based on a patch by Stephen Frost.
* Remove the row_security=force GUC value.Noah Misch2015-09-20
| | | | | | | | | | | | | | | | Every query of a single ENABLE ROW SECURITY table has two meanings, with the row_security GUC selecting between them. With row_security=force available, every function author would have been advised to either set the GUC locally or test both meanings. Non-compliance would have threatened reliability and, for SECURITY DEFINER functions, security. Authors already face an obligation to account for search_path, and we should not mimic that example. With this change, only BYPASSRLS roles need exercise the aforementioned care. Back-patch to 9.5, where the row_security GUC was introduced. Since this narrows the domain of pg_db_role_setting.setconfig and pg_proc.proconfig, one might bump catversion. A row_security=force setting in one of those columns will elicit a clear message, so don't.
* Be more wary about partially-valid LOCALLOCK data in RemoveLocalLock().Tom Lane2015-09-20
| | | | | | | | | | | | RemoveLocalLock() must consider the possibility that LockAcquireExtended() failed to palloc the initial space for a locallock's lockOwners array. I had evidently meant to cope with this hazard when the code was originally written (commit 1785acebf2ed14fd66955e2d9a55d77a025f418d), but missed that the pfree needed to be protected with an if-test. Just to make sure things are left in a clean state, reset numLockOwners as well. Per low-memory testing by Andreas Seltenreich. Back-patch to all supported branches.
* Add missing serial commaPeter Eisentraut2015-09-18
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* Remove trailing slashes from directories in find commandPeter Eisentraut2015-09-18
| | | | | | | BSD find is not very smart and ends up writing double slashes into the output in those cases. Also, xgettext is not very smart and splits the file names incorrectly in those cases, resulting in slightly incorrect file names being written into the POT file.
* Glue layer to connect the executor to the shm_mq mechanism.Robert Haas2015-09-18
| | | | | | | | | | | | | | | | | | | | | | | | | | The shm_mq mechanism was built to send error (and notice) messages and tuples between backends. However, shm_mq itself only deals in raw bytes. Since commit 2bd9e412f92bc6a68f3e8bcb18e04955cc35001d, we have had infrastructure for one message to redirect protocol messages to a queue and for another backend to parse them and do useful things with them. This commit introduces a somewhat analogous facility for tuples by adding a new type of DestReceiver, DestTupleQueue, which writes each tuple generated by a query into a shm_mq, and a new TupleQueueFunnel facility which reads raw tuples out of the queue and reconstructs the HeapTuple format expected by the executor. The TupleQueueFunnel abstraction supports reading from multiple tuple streams at the same time, but only in round-robin fashion. Someone could imaginably want other policies, but this should be good enough to meet our short-term needs related to parallel query, and we can always extend it later. This also makes one minor addition to the shm_mq API that didn' seem worth breaking out as a separate patch. Extracted from Amit Kapila's parallel sequential scan patch. This code was originally written by me, and then it was revised by Amit, and then it was revised some more by me.
* Cache argument type information in json(b) aggregate functions.Andrew Dunstan2015-09-18
| | | | | | | | | | | | | | These functions have been looking up type info for every row they process. Instead of doing that we only look them up the first time through and stash the information in the aggregate state object. Affects json_agg, json_object_agg, jsonb_agg and jsonb_object_agg. There is plenty more work to do in making these more efficient, especially the jsonb functions, but this is a virtually cost free improvement that can be done right away. Backpatch to 9.5 where the jsonb variants were introduced.
* Fix low-probability memory leak in regex execution.Tom Lane2015-09-18
| | | | | | | | | | | | | | | | After an internal failure in shortest() or longest() while pinning down the exact location of a match, find() forgot to free the DFA structure before returning. This is pretty unlikely to occur, since we just successfully ran the "search" variant of the DFA; but it could happen, and it would result in a session-lifespan memory leak since this code uses malloc() directly. Problem seems to have been aboriginal in Spencer's library, so back-patch all the way. In passing, correct a thinko in a comment I added awhile back about the meaning of the "ntree" field. I happened across these issues while comparing our code to Tcl's version of the library.
* Add header forgotten in 213335c14529a8d5e2007ec0c256f4cf64d62d3bTeodor Sigaev2015-09-18
| | | | Report from Peter Eisentraut
* Fix oversight in tsearch type checkTeodor Sigaev2015-09-17
| | | | | | | | | | Use IsBinaryCoercible() method instead of custom is_expected_type/is_text_type functions which was introduced when tsearch2 was moved into core. Per report by David E. Wheeler Analysis by Tom Lane Patch by me
* Add new function planstate_tree_walker.Robert Haas2015-09-17
| | | | | | | | | ExplainPreScanNode knows how to iterate over a generic tree of plan states; factor that logic out into a separate walker function so that other code, such as upcoming patches for parallel query, can also use it. Patch by me, reviewed by Tom Lane.
* Fix bug introduced by microvacuum for GiSTTeodor Sigaev2015-09-17
| | | | | | | | | | | | | | | Commit 013ebc0a7b7ea9c1b1ab7a3d4dd75ea121ea8ba7 introduces microvacuum for GiST, deletetion of tuple marked LP_DEAD uses IndexPageMultiDelete while recovery code uses IndexPageTupleDelete in loop. This causes a difference in offset numbers of tuples to delete. Patch introduces usage of IndexPageMultiDelete in GiST except gistplacetopage() where only one tuple is deleted at once. That also slightly improve performance, because IndexPageMultiDelete is more effective. Patch changes WAL format, so bump wal page magic. Bug report from Jeff Janes Diagnostic and patch by Anastasia Lubennikova and me
* Determine whether it's safe to attempt a parallel plan for a query.Robert Haas2015-09-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 924bcf4f16d54c55310b28f77686608684734f42 introduced a framework for parallel computation in PostgreSQL that makes most but not all built-in functions safe to execute in parallel mode. In order to have parallel query, we'll need to be able to determine whether that query contains functions (either built-in or user-defined) that cannot be safely executed in parallel mode. This requires those functions to be labeled, so this patch introduces an infrastructure for that. Some functions currently labeled as safe may need to be revised depending on how pending issues related to heavyweight locking under paralllelism are resolved. Parallel plans can't be used except for the case where the query will run to completion. If portal execution were suspended, the parallel mode restrictions would need to remain in effect during that time, but that might make other queries fail. Therefore, this patch introduces a framework that enables consideration of parallel plans only when it is known that the plan will be run to completion. This probably needs some refinement; for example, at bind time, we do not know whether a query run via the extended protocol will be execution to completion or run with a limited fetch count. Having the client indicate its intentions at bind time would constitute a wire protocol break. Some contexts in which parallel mode would be safe are not adjusted by this patch; the default is not to try parallel plans except from call sites that have been updated to say that such plans are OK. This commit doesn't introduce any parallel paths or plans; it just provides a way to determine whether they could potentially be used. I'm committing it on the theory that the remaining parallel sequential scan patches will also get committed to this release, hopefully in the not-too-distant future. Robert Haas and Amit Kapila. Reviewed (in earlier versions) by Noah Misch.
* Sync regex code with Tcl 8.6.4.Tom Lane2015-09-16
| | | | | | | | | | | | | | | | | | | Sync our regex code with upstream changes since last time we did this, which was Tcl 8.5.11 (see commit 08fd6ff37f71485e2fc04bc6ce07d2a483c36702). The only functional change here is to disbelieve that an octal escape is three digits long if it would exceed \377. That's a bug fix, but it's a minor one and could change the interpretation of working regexes, so don't back-patch. In addition to that, s/INFINITY/DUPINF/ to eliminate the risk of collisions with <math.h>'s macro, and s/LOCAL/NOPROP/ because that also seems like an unnecessarily collision-prone macro name. There were some other cosmetic changes in their copy that I did not adopt, notably a rather half-hearted attempt at renaming some of the C functions in a more verbose style. (I'm not necessarily against the concept, but renaming just a few functions in the package is not an improvement.)
* Enforce ALL/SELECT policies in RETURNING for RLSStephen Frost2015-09-15
| | | | | | | | | | | | For the UPDATE/DELETE RETURNING case, filter the records which are not visible to the user through ALL or SELECT policies from those considered for the UPDATE or DELETE. This is similar to how the GRANT system works, which prevents RETURNING unless the caller has SELECT rights on the relation. Per discussion with Robert, Dean, Tom, and Kevin. Back-patch to 9.5 where RLS was introduced.