aboutsummaryrefslogtreecommitdiff
path: root/src/backend
Commit message (Collapse)AuthorAge
* Rethink MemoryContext creation to improve performance.Tom Lane2017-12-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch makes a number of interrelated changes to reduce the overhead involved in creating/deleting memory contexts. The key ideas are: * Include the AllocSetContext header of an aset.c context in its first malloc request, rather than allocating it separately in TopMemoryContext. This means that we now always create an initial or "keeper" block in an aset, even if it never receives any allocation requests. * Create freelists in which we can save and recycle recently-destroyed asets (this idea is due to Robert Haas). * In the common case where the name of a context is a constant string, just store a pointer to it in the context header, rather than copying the string. The first change eliminates a palloc/pfree cycle per context, and also avoids bloat in TopMemoryContext, at the price that creating a context now involves a malloc/free cycle even if the context never receives any allocations. That would be a loser for some common usage patterns, but recycling short-lived contexts via the freelist eliminates that pain. Avoiding copying constant strings not only saves strlen() and strcpy() overhead, but is an essential part of the freelist optimization because it makes the context header size constant. Currently we make no attempt to use the freelist for contexts with non-constant names. (Perhaps someday we'll need to think harder about that, but in current usage, most contexts with custom names are long-lived anyway.) The freelist management in this initial commit is pretty simplistic, and we might want to refine it later --- but in common workloads that will never matter because the freelists will never get full anyway. To create a context with a non-constant name, one is now required to call AllocSetContextCreateExtended and specify the MEMCONTEXT_COPY_NAME option. AllocSetContextCreate becomes a wrapper macro, and it includes a test that will complain about non-string-literal context name parameters on gcc and similar compilers. An unfortunate side effect of making AllocSetContextCreate a macro is that one is now *required* to use the size parameter abstraction macros (ALLOCSET_DEFAULT_SIZES and friends) with it; the pre-9.6 habit of writing out individual size parameters no longer works unless you switch to AllocSetContextCreateExtended. Internally to the memory-context-related modules, the context creation APIs are simplified, removing the rather baroque original design whereby a context-type module called mcxt.c which then called back into the context-type module. That saved a bit of code duplication, but not much, and it prevented context-type modules from exercising control over the allocation of context headers. In passing, I converted the test-and-elog validation of aset size parameters into Asserts to save a few more cycles. The original thought was that callers might compute size parameters on the fly, but in practice nobody does that, so it's useless to expend cycles on checking those numbers in production builds. Also, mark the memory context method-pointer structs "const", just for cleanliness. Discussion: https://postgr.es/m/2264.1512870796@sss.pgh.pa.us
* Fix crash when using CALL on an aggregatePeter Eisentraut2017-12-13
| | | | | Author: Ashutosh Bapat <ashutosh.bapat@enterprisedb.com> Reported-by: Rushabh Lathia <rushabh.lathia@gmail.com>
* Add float.h include to int8.c, for isnan().Andres Freund2017-12-12
| | | | | | | | port.h redirects isnan() to _isnan() on windows, which in turn is provided by float.h rather than math.h. Therefore include the latter as well. Per buildfarm.
* Consistently use PG_INT(16|32|64)_(MIN|MAX).Andres Freund2017-12-12
| | | | Per buildfarm animal woodlouse.
* Use new overflow aware integer operations.Andres Freund2017-12-12
| | | | | | | | | | | | | | | | | A previous commit added inline functions that provide fast(er) and correct overflow checks for signed integer math. Use them in a significant portion of backend code. There's more to touch in both backend and frontend code, but these were the easily identifiable cases. The old overflow checks are noticeable in integer heavy workloads. A secondary benefit is that getting rid of overflow checks that rely on signed integer overflow wrapping around, will allow us to get rid of -fwrapv in the future. Which in turn slows down other code. Author: Andres Freund Discussion: https://postgr.es/m/20171024103954.ztmatprlglz3rwke@alap3.anarazel.de
* Remove obsolete comment.Robert Haas2017-12-12
| | | | | | | | | | | | Commit 8b304b8b72b0a60f1968d39f01cf817c8df863ec removed replacement selection, but left behind this comment text. The optimization to which the comment refers is not relevant without replacement selection, because if we had so few tuples as to require only one tape, we would have just completed the sort in memory. Peter Geoghegan Discussion: http://postgr.es/m/CAH2-WznqupLA8CMjp+vqzoe0yXu0DYYbQSNZxmgN76tLnAOZ_w@mail.gmail.com
* Remove bug from OPTIMIZER_DEBUG code for partition-wise join.Robert Haas2017-12-12
| | | | | | Etsuro Fujita, reviewed by Ashutosh Bapat Discussion: http://postgr.es/m/5A2A60E6.6000008@lab.ntt.co.jp
* Fix commentPeter Eisentraut2017-12-11
| | | | Reported-by: Noah Misch <noah@leadboat.com>
* Fix corner-case coredump in _SPI_error_callback().Tom Lane2017-12-11
| | | | | | | | | | | I noticed that _SPI_execute_plan initially sets spierrcontext.arg = NULL, and only fills it in some time later. If an error were to happen in between, _SPI_error_callback would try to dereference the null pointer. This is unlikely --- there's not much between those points except push-snapshot calls --- but it's clearly not impossible. Tweak the callback to do nothing if the pointer isn't set yet. It's been like this for awhile, so back-patch to all supported branches.
* Improve comment about PartitionBoundInfoData.Robert Haas2017-12-11
| | | | | | | Ashutosh Bapat, per discussion with Julien Rouhaund, who also reviewed this patch. Discussion: http://postgr.es/m/CAFjFpReBR3ftK9C23LLCZY_TDXhhjB_dgE-L9+mfTnA=gkvdvQ@mail.gmail.com
* Fix typoMagnus Hagander2017-12-09
| | | | Reported by Robins Tharakan
* Prohibit identity columns on typed tables and partitionsPeter Eisentraut2017-12-08
| | | | | | | | | | Those cases currently crash and supporting them is more work then originally thought, so we'll just prohibit these scenarios for now. Author: Michael Paquier <michael.paquier@gmail.com> Reviewed-by: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp> Reported-by: Мансур Галиев <gomer94@yandex.ru> Bug: #14866
* Fix mistake in commentPeter Eisentraut2017-12-08
| | | | Reported-by: Masahiko Sawada <sawada.mshk@gmail.com>
* Apply identity sequence values on COPYPeter Eisentraut2017-12-08
| | | | | | | | | | | A COPY into a table should apply identity sequence values just like it does for ordinary defaults. This was previously forgotten, leading to null values being inserted, which in turn would fail because identity columns have not-null constraints. Author: Michael Paquier <michael.paquier@gmail.com> Reported-by: Steven Winfield <steven.winfield@cantabcapital.com> Bug: #14952
* Report failure to start a background worker.Robert Haas2017-12-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a worker is flagged as BGW_NEVER_RESTART and we fail to start it, or if it is not marked BGW_NEVER_RESTART but is terminated before startup succeeds, what BgwHandleStatus should be reported? The previous code really hadn't considered this possibility (as indicated by the comments which ignore it completely) and would typically return BGWH_NOT_YET_STARTED, but that's not a good answer, because then there's no way for code using GetBackgroundWorkerPid() to tell the difference between a worker that has not started but will start later and a worker that has not started and will never be started. So, when this case happens, return BGWH_STOPPED instead. Update the comments to reflect this. The preceding fix by itself is insufficient to fix the problem, because the old code also didn't send a notification to the process identified in bgw_notify_pid when startup failed. That might've been technically correct under the theory that the status of the worker was BGWH_NOT_YET_STARTED, because the status would indeed not change when the worker failed to start, but now that we're more usefully reporting BGWH_STOPPED, a notification is needed. Without these fixes, code which starts background workers and then uses the recommended APIs to wait for those background workers to start would hang indefinitely if the postmaster failed to fork a worker. Amit Kapila and Robert Haas Discussion: http://postgr.es/m/CAA4eK1KDfKkvrjxsKJi3WPyceVi3dH1VCkbTJji2fuwKuB=3uw@mail.gmail.com
* Fix Parallel Append crash.Robert Haas2017-12-06
| | | | | | | | | Reported by Tom Lane and the buildfarm. Amul Sul and Amit Khandekar Discussion: http://postgr.es/m/17868.1512519318@sss.pgh.pa.us Discussion: http://postgr.es/m/CAJ3gD9cJQ4d-XhmZ6BqM9rMM2KDBfpkdgOAb4+psz56uBuMQ_A@mail.gmail.com
* Support Parallel Append plan nodes.Robert Haas2017-12-05
| | | | | | | | | | | | | | | | | | | | When we create an Append node, we can spread out the workers over the subplans instead of piling on to each subplan one at a time, which should typically be a bit more efficient, both because the startup cost of any plan executed entirely by one worker is paid only once and also because of reduced contention. We can also construct Append plans using a mix of partial and non-partial subplans, which may allow for parallelism in places that otherwise couldn't support it. Unfortunately, this patch doesn't handle the important case of parallelizing UNION ALL by running each branch in a separate worker; the executor infrastructure is added here, but more planner work is needed. Amit Khandekar, Robert Haas, Amul Sul, reviewed and tested by Ashutosh Bapat, Amit Langote, Rafia Sabih, Amit Kapila, and Rajkumar Raghuwanshi. Discussion: http://postgr.es/m/CAJ3gD9dy0K_E8r727heqXoBmWZ83HwLFwdcaSSmBQ1+S+vRuUQ@mail.gmail.com
* Fix accumulation of parallel worker instrumentation.Robert Haas2017-12-05
| | | | | | | | | | | | | When a Gather or Gather Merge node is started and stopped multiple times, the old code wouldn't reset the shared state between executions, potentially resulting in dramatically inflated instrumentation data for nodes beneath it. (The per-worker instrumentation ended up OK, I think, but the overall totals were inflated.) Report by hubert depesz lubaczewski. Analysis and fix by Amit Kapila, reviewed and tweaked a bit by me. Discussion: http://postgr.es/m/20171127175631.GA405@depesz.com
* Fix EXPLAIN ANALYZE of hash join when the leader doesn't participate.Andres Freund2017-12-05
| | | | | | | | | | | | | | | | | | | | If a hash join appears in a parallel query, there may be no hash table available for explain.c to inspect even though a hash table may have been built in other processes. This could happen either because parallel_leader_participation was set to off or because the leader happened to hit the end of the outer relation immediately (even though the complete relation is not empty) and decided not to build the hash table. Commit bf11e7ee introduced a way for workers to exchange instrumentation via the DSM segment for Sort nodes even though they are not parallel-aware. This commit does the same for Hash nodes, so that explain.c has a way to find instrumentation data from an arbitrary participant that actually built the hash table. Author: Thomas Munro Reviewed-By: Andres Freund Discussion: https://postgr.es/m/CAEepm%3D3DUQC2-z252N55eOcZBer6DPdM%3DFzrxH9dZc5vYLsjaA%40mail.gmail.com
* Treat directory open failures as hard errors in ResetUnloggedRelations().Tom Lane2017-12-04
| | | | | | | | | | | | | | | | | | | | | | | | | | Previously, this code just reported such problems at LOG level and kept going. The problem with this approach is that transient failures (e.g., ENFILE) could prevent us from resetting unlogged relations to empty, yet allow recovery to appear to complete successfully. That seems like a data corruption hazard large enough to treat such problems as reasons to fail startup. For the same reason, treat unlink failures for unlogged files as hard errors not just LOG messages. It's a little odd that we did it like that when file-level errors in other steps (copy_file, fsync_fname) are ERRORs. The sole case that I left alone is that ENOENT failure on a tablespace (not database) directory is not an error, though it will now be logged rather than just silently ignored. This is to cover the scenario where a previous DROP TABLESPACE removed the tablespace directory but failed before removing the pg_tblspc symlink. I'm not sure that that's very likely in practice, but that seems like the only real excuse for the old behavior here, so let's allow for it. (As coded, this will also allow ENOENT on $PGDATA/base/. But since we'll fail soon enough if that's gone, I don't think we need to complicate this code by distinguishing that from a true tablespace case.) Discussion: https://postgr.es/m/21040.1512418508@sss.pgh.pa.us
* Simplify do_pg_start_backup's API by opening pg_tblspc internally.Tom Lane2017-12-04
| | | | | | | | | | | | | do_pg_start_backup() expects its callers to pass in an open DIR pointer for the pg_tblspc directory, but there's no apparent advantage in that. It complicates the callers without adding any flexibility, and there's no robustness advantage, since we surely have to be prepared for errors during the scan of pg_tblspc anyway. In fact, by holding an extra kernel resource during operations like the preliminary checkpoint, we might be making things a fraction more failure-prone not less. Hence, remove that argument and open the directory just for the duration of the actual scan. Discussion: https://postgr.es/m/28752.1512413887@sss.pgh.pa.us
* Improve error handling in RemovePgTempFiles().Tom Lane2017-12-04
| | | | | | | | | | | | | | | | | | | | | | | | Modify this function and its subsidiaries so that syscall failures are reported via ereport(LOG), rather than silently ignored as before. We don't want to throw a hard ERROR, as that would prevent database startup, and getting rid of leftover temporary files is not important enough for that. On the other hand, not reporting trouble at all seems like an odd choice not in line with current project norms, especially since any failure here is quite unexpected. On the same reasoning, adjust these functions' AllocateDir/ReadDir calls so that failure to scan a directory results in LOG not ERROR. I also removed the previous practice of silently ignoring ENOENT failures during directory opens --- there are some corner cases where that could happen given a previous database crash, but that seems like a bad excuse for ignoring a condition that isn't expected in most cases. A LOG message during postmaster start seems OK in such situations, and better than no output at all. In passing, make RemovePgTempRelationFiles' test for "is the file name all digits" look more like the way it's done elsewhere. Discussion: https://postgr.es/m/19907.1512402254@sss.pgh.pa.us
* Clean up assorted messiness around AllocateDir() usage.Tom Lane2017-12-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes a couple of low-probability bugs that could lead to reporting an irrelevant errno value (and hence possibly a wrong SQLSTATE) concerning directory-open or file-open failures. It also fixes places where we took shortcuts in reporting such errors, either by using elog instead of ereport or by using ereport but forgetting to specify an errcode. And it eliminates a lot of just plain redundant error-handling code. In service of all this, export fd.c's formerly-static function ReadDirExtended, so that external callers can make use of the coding pattern dir = AllocateDir(path); while ((de = ReadDirExtended(dir, path, LOG)) != NULL) if they'd like to treat directory-open failures as mere LOG conditions rather than errors. Also fix FreeDir to be a no-op if we reach it with dir == NULL, as such a coding pattern would cause. Then, remove code at many call sites that was throwing an error or log message for AllocateDir failure, as ReadDir or ReadDirExtended can handle that job just fine. Aside from being a net code savings, this gets rid of a lot of not-quite-up-to-snuff reports, as mentioned above. (In some places these changes result in replacing a custom error message such as "could not open tablespace directory" with more generic wording "could not open directory", but it was agreed that the custom wording buys little as long as we report the directory name.) In some other call sites where we can't just remove code, change the error reports to be fully project-style-compliant. Also reorder code in restoreTwoPhaseData that was acquiring a lock between AllocateDir and ReadDir; in the unlikely but surely not impossible case that LWLockAcquire changes errno, AllocateDir failures would be misreported. There is no great value in opening the directory before acquiring TwoPhaseStateLock, so just do it in the other order. Also fix CheckXLogRemoved to guarantee that it preserves errno, as quite a number of call sites are implicitly assuming. (Again, it's unlikely but I think not impossible that errno could change during a SpinLockAcquire. If so, this function was broken for its own purposes as well as breaking callers.) And change a few places that were using not-per-project-style messages, such as "could not read directory" when "could not open directory" is more correct. Back-patch the exporting of ReadDirExtended, in case we have occasion to back-patch some fix that makes use of it; it's not needed right now but surely making it global is pretty harmless. Also back-patch the restoreTwoPhaseData and CheckXLogRemoved fixes. The rest of this is essentially cosmetic and need not get back-patched. Michael Paquier, with a bit of additional work by me Discussion: https://postgr.es/m/CAB7nPqRpOCxjiirHmebEFhXVTK7V5Jvw4bz82p7Oimtsm3TyZA@mail.gmail.com
* When VACUUM or ANALYZE skips a concurrently dropped table, log it.Robert Haas2017-12-04
| | | | | | | Hopefully, the additional logging will help avoid confusion that could otherwise result. Nathan Bossart, reviewed by Michael Paquier, Fabrízio Mello, and me
* Support boolean columns in functional-dependency statistics.Tom Lane2017-12-04
| | | | | | | | | | | | | | | | | | | | | | | There's no good reason that the multicolumn stats stuff shouldn't work on booleans. But it looked only for "Var = pseudoconstant" clauses, and it will seldom find those for boolean Vars, since earlier phases of planning will fold "boolvar = true" or "boolvar = false" to just "boolvar" or "NOT boolvar" respectively. Improve dependencies_clauselist_selectivity() to recognize such clauses as equivalent to equality restrictions. This fixes a failure of the extended stats mechanism to apply in a case reported by Vitaliy Garnashevich. It's not a complete solution to his problem because the bitmap-scan costing code isn't consulting extended stats where it should, but that's surely an independent issue. In passing, improve some comments, get rid of a NumRelids() test that's redundant with the preceding bms_membership() test, and fix dependencies_clauselist_selectivity() so that estimatedclauses actually is a pure output argument as stated by its API contract. Back-patch to v10 where this code was introduced. Discussion: https://postgr.es/m/73a4936d-2814-dc08-ed0c-978f76f435b0@gmail.com
* Remove memory leak protection from Gather and Gather Merge nodes.Robert Haas2017-12-04
| | | | | | | | | | | | | | Before commit 6b65a7fe62e129d5c2b85cd74d6a91d8f7564608, tqueue.c could perform tuple remapping and thus leak memory, which is why commit af33039317ddc4a0e38a02e2255c2bf453115fd2 made TupleQueueReaderNext run in a short-lived context. Now, however, tqueue.c has been reduced to a shadow of its former self, and there shouldn't be any chance of leaks any more. Accordingly, remove some tuple copying and memory context manipulation to speed up processing. Patch by me, reviewed by Amit Kapila. Some testing by Rafia Sabih. Discussion: http://postgr.es/m/CAA4eK1LSDydwrNjmYSNkfJ3ZivGSWH9SVswh6QpNzsMdj_oOQA@mail.gmail.com
* Adjust #ifdef EXEC_BACKEND RemovePgTempFilesInDir() call.Andres Freund2017-12-01
| | | | | | | Other callers were adjusted in the course of dc6c4c9dc2a111519b76b22daaaac86c5608223b. Per buildfarm.
* Add infrastructure for sharing temporary files between backends.Andres Freund2017-12-01
| | | | | | | | | | | | | | | | | SharedFileSet allows temporary files to be created by one backend and then exported for read-only access by other backends, with clean-up managed by reference counting associated with a DSM segment. This includes changes to fd.c and buffile.c to support the new kind of temporary file. This will be used by an upcoming patch adding support for parallel hash joins. Author: Thomas Munro Reviewed-By: Peter Geoghegan, Andres Freund, Robert Haas, Rushabh Lathia Discussion: https://postgr.es/m/CAEepm=2W=cOkiZxcg6qiFQP-dHUe09aqTrEMM7yJDrHMhDv_RA@mail.gmail.com https://postgr.es/m/CAH2-WznJ_UgLux=_jTgCQ4yFz0iBntudsNKa1we3kN1BAG=88w@mail.gmail.com
* Minor code beautification in partition_bounds_equal.Robert Haas2017-12-01
| | | | | | | | | Use get_greatest_modulus more consistently, instead of doing the same thing in an ad-hoc manner in this one place. Ashutosh Bapat Discussion: http://postgr.es/m/CAFjFpReT9L4RCiJBKOyWC2=i02kv9uG2fx=4Fv7kFY2t0SPCgw@mail.gmail.com
* Re-allow INSERT .. ON CONFLICT DO NOTHING on partitioned tables.Robert Haas2017-12-01
| | | | | | | | | | | | Commit 8355a011a0124bdf7ccbada206a967d427039553 was reverted in f05230752d53c4aa74cffa9b699983bbb6bcb118, but this attempt is hopefully better-considered: we now pass the correct value to ExecOpenIndices, which should avoid the crash that we hit before. Amit Langote, reviewed by Simon Riggs and by me. Some final editing by me. Discussion: http://postgr.es/m/7ff1e8ec-dc39-96b1-7f47-ff5965dceeac@lab.ntt.co.jp
* Try to exclude partitioned tables in toto.Robert Haas2017-12-01
| | | | | | Ashutosh Bapat, reviewed by Jeevan Chalke. Comment by me. Discussion: http://postgr.es/m/CAFjFpRcuRaydz88CY_aQekmuvmN2A9ax5z0k=ppT+s8KS8xMRA@mail.gmail.com
* Fix uninitialized memory reference.Robert Haas2017-12-01
| | | | | | | | | | | Without this, when partdesc->nparts == 0, we end up calling ExecBuildSlotPartitionKeyDescription without initializing values and isnull. Reported by Coverity via Michael Paquier. Patch by Michael Paquier, reviewed and revised by Amit Langote. Discussion: http://postgr.es/m/CAB7nPqQ3mwkdMoPY-ocgTpPnjd8TKOadMxdTtMLvEzF8480Zfg@mail.gmail.com
* Check channel binding flag at end of SCRAM exchangePeter Eisentraut2017-12-01
| | | | | | | We need to check whether the channel-binding flag encoded in the client-final-message is the same one sent in the client-first-message. Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
* Remove extra word from comment.Robert Haas2017-11-30
| | | | | | | | | David Rowley, who also was the primary author of the patch that added this function; the attribution in my previous commit, 84940644de931f331433b35e3a391822671f8c9c, was incorrect due to sloppiness on my part. Discussion: http://postgr.es/m/CAKJS1f_0iSiLQsf_c06AzOWAc3eS6ePjjVQFpcFv3W-O5aktnQ@mail.gmail.com
* SQL proceduresPeter Eisentraut2017-11-30
| | | | | | | | | | | | | | | | | | | | | This adds a new object type "procedure" that is similar to a function but does not have a return type and is invoked by the new CALL statement instead of SELECT or similar. This implementation is aligned with the SQL standard and compatible with or similar to other SQL implementations. This commit adds new commands CALL, CREATE/ALTER/DROP PROCEDURE, as well as ALTER/DROP ROUTINE that can refer to either a function or a procedure (or an aggregate function, as an extension to SQL). There is also support for procedures in various utility commands such as COMMENT and GRANT, as well as support in pg_dump and psql. Support for defining procedures is available in all the languages supplied by the core distribution. While this commit is mainly syntax sugar around existing functionality, future features will rely on having procedures as a separate object type. Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>
* Make create_unique_path manage memory like mark_dummy_rel.Robert Haas2017-11-30
| | | | | | | | | | | | | | | | | | Put the unique path in the same context as the owning RelOptInfo, rather than the toplevel planner context. This is how this function worked originally, but commit f41803bb39bc2949db200116a609fd242d0ec221 changed it without explanation. mark_dummy_rel adopted the older (or newer?) technique in commit eca75a12a27d28b972fc269c1c8813cd8eb15441, which also featured a much better explanation of why it is correct. So, switch back to that technique here, with the same explanation given there. Although this fixes a possible memory leak when GEQO is in use, the leak is minor and probably nobody cares, so no back-patch. Ashutosh Bapat, reviewed by Tom Lane and by me Discussion: http://postgr.es/m/CAFjFpRcXkHHrXyD9BCvkgGJV4TnHG2SWJ0PhJfrDu3NAcQvh7g@mail.gmail.com
* Fix neqjoinsel's behavior for semi/anti join cases.Tom Lane2017-11-29
| | | | | | | | | | | | | | | | | | | | | | | Previously, this function estimated the selectivity as 1 minus eqjoinsel() for the negator equality operator, regardless of join type (I think there was an expectation that eqjoinsel would handle the join type). But actually this is completely wrong for semijoin cases: the fraction of the LHS that has a non-matching row is not one minus the fraction of the LHS that has a matching row. In reality a semijoin with <> will nearly always succeed: it can only fail when the RHS is empty, or it contains a single distinct value that is equal to the particular LHS value, or the LHS value is null. The only one of those things we should have much confidence in estimating is the fraction of LHS values that are null, so let's just take the selectivity as 1 minus outer nullfrac. Per coding convention, antijoin should be estimated the same as semijoin. Arguably this is a bug fix, but in view of the lack of field complaints and the risk of destabilizing plans, no back-patch. Thomas Munro, reviewed by Ashutosh Bapat Discussion: https://postgr.es/m/CAEepm=270ze2hVxWkJw-5eKzc3AB4C9KpH3L2kih75R5pdSogg@mail.gmail.com
* Add a barrier primitive for synchronizing backends.Andres Freund2017-11-29
| | | | | | | | | | | | | | | | Provide support for dynamic or static parties of processes to wait for all processes to reach point in the code before continuing. This is similar to the mechanism of the same name in POSIX threads and MPI, though has explicit phasing and dynamic party support like the Java core library's Phaser. This will be used by an upcoming patch adding support for parallel hash joins. Author: Thomas Munro Reviewed-By: Andres Freund Discussion: https://postgr.es/m/CAEepm=2_y7oi01OjA_wLvYcWMc9_d=LaoxrY3eiROCZkB_qakA@mail.gmail.com
* New C function: bms_add_rangeRobert Haas2017-11-29
| | | | | | | | | | | This will be used by pending patches to improve partition pruning. Amit Langote and Kyotaro Horiguchi, per a suggestion from David Rowley. Review and testing of the larger patch set of which this is a part by Ashutosh Bapat, David Rowley, Dilip Kumar, Jesper Pedersen, Rajkumar Raghuwanshi, Beena Emerson, Amul Sul, and Kyotaro Horiguchi. Discussion: http://postgr.es/m/098b9c71-1915-1a2a-8d52-1a7a50ce79e8@lab.ntt.co.jp
* Update typedefs.list and re-run pgindentRobert Haas2017-11-29
| | | | Discussion: http://postgr.es/m/CA+TgmoaA9=1RWKtBWpDaj+sF3Stgc8sHgf5z=KGtbjwPLQVDMA@mail.gmail.com
* Clarify old comment about qual_is_pushdown_safe's handling of subplans.Tom Lane2017-11-28
| | | | | This comment glossed over the difference between initplans and subplans, but they are indeed different for our purposes here.
* Make memset() use sizeof() rather than re-compute sizeAlvaro Herrera2017-11-29
| | | | | | | This is simpler and more closely follows overwhelming precedent. Report and patch by Mark Dilger. Discussion: https://postgr.es/m/9A68FB88-5F45-4848-9926-8586E2D777D1@gmail.com
* Fix extstat collection when no stats are produced for a columnAlvaro Herrera2017-11-28
| | | | | | | This is a mistakenly placed conditional in bf2a691e02d7. Reported by Justin Pryzby Discussion: https://postgr.es/m/20171117214352.GE25796@telsasoft.com
* Fix wrong function name in comment.Robert Haas2017-11-28
| | | | | | Rushabh Lathia Discussion: http://postgr.es/m/CAGPqQf2z5g+7YmGZSZgKoiFsaUB+63Rzmz8-5PQHuS6hd14FEg@mail.gmail.com
* If a range-partitioned table has no default partition, reject null keys.Robert Haas2017-11-28
| | | | | | | | | | Commit 4e5fe9ad19e14af360de7970caa8b150436c9dec introduced this problem. Also add a test so it doesn't get broken again. Report by Rushabh Lathia. Fix by Amit Langote. Reviewed by Rushabh Lathia and Amul Sul. Tweaked by me. Discussion: http://postgr.es/m/CAGPqQf0Y1iJyk4QJBdMf=pS9i6Q0JUMM_h5-qkR3OMJ-e04PyA@mail.gmail.com
* Fix ReinitializeParallelDSM to tolerate finding no error queues.Robert Haas2017-11-28
| | | | | | | | | | | | | | | | Commit d4663350646ca0c069a36d906155a0f7e3372eb7 changed things so that shm_toc_lookup would fail with an error rather than silently returning NULL in the hope that such failures would be reported in a useful way rather than via a system crash. However, it overlooked the fact that the lookup of PARALLEL_KEY_ERROR_QUEUE in ReinitializeParallelDSM is expected to fail when no DSM segment was created in the first place; in that case, we end up with a backend-private memory segment that still contains an entry for PARALLEL_KEY_FIXED but no others. Consequently a benign failure to initialize parallelism can escalate into an elog(ERROR); repair. Discussion: http://postgr.es/m/CA+Tgmob8LFw55DzH1QEREpBEA9RJ_W_amhBFCVZ6WMwUhVpOqg@mail.gmail.com
* Teach bitmap heap scan to cope with absence of a DSA.Robert Haas2017-11-28
| | | | | | | | | | | | If we have a plan that uses parallelism but are unable to execute it using parallelism, for example due to a lack of available DSM segments, then the EState's es_query_dsa will be NULL. Parallel bitmap heap scan needs to fall back to a non-parallel scan in such cases. Patch by me, reviewed by Dilip Kumar Discussion: http://postgr.es/m/CAEepm=0kADK5inNf_KuemjX=HQ=PuTP0DykM--fO5jS5ePVFEA@mail.gmail.com
* Add null test to partition constraint for default range partitions.Robert Haas2017-11-28
| | | | | | | | | | | | | | | Non-default range partitions have a constraint which include null tests, and both default and non-default list partitions also have a constraint which includes null tests, but for some reason this was missed for default range partitions. This could cause the partition constraint to evaluate to false for rows that were (correctly) routed to that partition by insert tuple routing, which could in turn cause constraint exclusion to prune the default partition in cases where it should not. Amit Langote, reviewed by Kyotaro Horiguchi Discussion: http://postgr.es/m/ba7aaeb1-4399-220e-70b4-62eade1522d0@lab.ntt.co.jp
* Fix typo.Robert Haas2017-11-28
| | | | | | Masahiko Sawada Discussion: http://postgr.es/m/CAD21AoCq_QG6UEo6yb-purmhLQjDLsCA2_B+8Wh3ah9P2-XmrQ@mail.gmail.com
* Fix assorted syscache lookup sloppiness in partition-related code.Tom Lane2017-11-27
| | | | | | | | | | | | | | | | | | | | | heap_drop_with_catalog and ATExecDetachPartition neglected to check for SearchSysCache failures, as noted in bugs #14927 and #14928 from Pan Bian. Such failures are pretty unlikely, since we should already have some sort of lock on the rel at these points, but it's neither a good idea nor per project style to omit a check for failure. Also, StorePartitionKey contained a syscache lookup that it never did anything with, including never releasing the result. Presumably the reason why we don't see refcount-leak complaints is that the lookup always fails; but in any case it's pretty useless, so remove it. All of these errors were evidently introduced by the relation partitioning feature. Back-patch to v10 where that came in. Amit Langote and Tom Lane Discussion: https://postgr.es/m/20171127090105.1463.3962@wrigleys.postgresql.org Discussion: https://postgr.es/m/20171127091341.1468.72696@wrigleys.postgresql.org