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* Reduce lock levels for table storage params related to planningSimon Riggs2017-03-06
| | | | | | | | | | | | The following parameters are now updateable with ShareUpdateExclusiveLock effective_io_concurrency parallel_workers seq_page_cost random_page_cost n_distinct n_distinct_inherited Simon Riggs and Fabrízio Mello
* Improve error reporting for tuple-routing failures.Robert Haas2017-03-03
| | | | | | | | | | | Currently, the whole row is shown without column names. Instead, adopt a style similar to _bt_check_unique() in ExecFindPartition() and show the failing key: (key1, ...) = (val1, ...). Amit Langote, per a complaint from Simon Riggs. Reviewed by me; I also adjusted the grammar in one of the comments. Discussion: http://postgr.es/m/9f9dc7ae-14f0-4a25-5485-964d9bfc19bd@lab.ntt.co.jp
* hash: Refactor and clean up bucket split code.Robert Haas2017-03-01
| | | | | | | | | | | As with commit 30df93f698d016d086e8961aa6c6076b37ea0ef4 and commit b0f18cb77f50a54e997d857d592f6a511617f52c, the goal here is to move all of the related page modifications to a single section of code, in preparation for adding write-ahead logging. Amit Kapila, with slight changes by me. The larger patch series of which this is a part has been reviewed and tested by Álvaro Herrera, Ashutosh Sharma, Mark Kirkwood, Jeff Janes, and Jesper Pedersen.
* Fix incorrect variable datatypeMagnus Hagander2017-02-28
| | | | | | | Both datatypes map to the same underlying one which is why it still worked, but we should use the correct type. Author: Kyotaro HORIGUCHI
* Allow index AMs to return either HeapTuple or IndexTuple format during IOS.Tom Lane2017-02-27
| | | | | | | | | | | | | | | | | | | | | | Previously, only IndexTuple format was supported for the output data of an index-only scan. This is fine for btree, which is just returning a verbatim index tuple anyway. It's not so fine for SP-GiST, which can return reconstructed data that's much larger than a page. To fix, extend the index AM API so that index-only scan data can be returned in either HeapTuple or IndexTuple format. There's other ways we could have done it, but this way avoids an API break for index AMs that aren't concerned with the issue, and it costs little except a couple more fields in IndexScanDescs. I changed both GiST and SP-GiST to use the HeapTuple method. I'm not very clear on whether GiST can reconstruct data that's too large for an IndexTuple, but that seems possible, and it's not much of a code change to fix. Per a complaint from Vik Fearing. Reviewed by Jason Li. Discussion: https://postgr.es/m/49527f79-530d-0bfe-3dad-d183596afa92@2ndquadrant.fr
* hash: Refactor overflow page allocation.Robert Haas2017-02-27
| | | | | | | | | | | | As with commit b0f18cb77f50a54e997d857d592f6a511617f52c, the goal here is to move all of the related page modifications to a single section of code, in preparation for adding write-ahead logging. Amit Kapila, with slight changes by me. The larger patch series of which this is a part has been reviewed and tested by Álvaro Herrera, Ashutosh Sharma, Mark Kirkwood, Jeff Janes, and Jesper Pedersen, all of whom should also have been credited in the previous commit message.
* hash: Refactor bucket squeeze code.Robert Haas2017-02-27
| | | | | | | | | | | | In preparation for adding write-ahead logging to hash indexes, refactor _hash_freeovflpage and _hash_squeezebucket so that all related page modifications happen in a single section of code. The previous coding assumed that it would be fine to move tuples one at a time, and also that the various operations involved in freeing an overflow page didn't necessarily all need to be done together, all of which is true if you don't care about write-ahead logging. Amit Kapila, with slight changes by me.
* Remove useless duplicate inclusions of system header files.Tom Lane2017-02-25
| | | | | | | | | | | | | | | | c.h #includes a number of core libc header files, such as <stdio.h>. There's no point in re-including these after having read postgres.h, postgres_fe.h, or c.h; so remove code that did so. While at it, also fix some places that were ignoring our standard pattern of "include postgres[_fe].h, then system header files, then other Postgres header files". While there's not any great magic in doing it that way rather than system headers last, it's silly to have just a few files deviating from the general pattern. (But I didn't attempt to enforce this globally, only in files I was touching anyway.) I'd be the first to say that this is mostly compulsive neatnik-ism, but over time it might save enough compile cycles to be useful.
* Consistently declare timestamp variables as TimestampTz.Tom Lane2017-02-23
| | | | | | | | | | | | | | | | | | | Twiddle the replication-related code so that its timestamp variables are declared TimestampTz, rather than the uninformative "int64" that was previously used for meant-to-be-always-integer timestamps. This resolves the int64-vs-TimestampTz declaration inconsistencies introduced by commit 7c030783a, though in the opposite direction to what was originally suggested. This required including datatype/timestamp.h in a couple more places than before. I decided it would be a good idea to slim down that header by not having it pull in <float.h> etc, as those headers are no longer at all relevant to its purpose. Unsurprisingly, a small number of .c files turn out to have been depending on those inclusions, so add them back in the .c files as needed. Discussion: https://postgr.es/m/26788.1487455319@sss.pgh.pa.us Discussion: https://postgr.es/m/27694.1487456324@sss.pgh.pa.us
* Remove pg_control's enableIntTimes field.Tom Lane2017-02-23
| | | | | | | | | | | | | | | We don't need it any more. pg_controldata continues to report that date/time type storage is "64-bit integers", but that's now a hard-wired behavior not something it sees in the data. This avoids breaking pg_upgrade, and perhaps other utilities that inspect pg_control this way. Ditto for pg_resetwal. I chose to remove the "bigint_timestamps" output column of pg_control_init(), though, as that function hasn't been around long and probably doesn't have ossified users. Discussion: https://postgr.es/m/26788.1487455319@sss.pgh.pa.us
* Add optimizer and executor support for parallel index scans.Robert Haas2017-02-15
| | | | | | | | | | | | In combination with 569174f1be92be93f5366212cc46960d28a5c5cd, which taught the btree AM how to perform parallel index scans, this allows parallel index scan plans on btree indexes. This infrastructure should be general enough to support parallel index scans for other index AMs as well, if someone updates them to support parallel scans. Amit Kapila, reviewed and tested by Anastasia Lubennikova, Tushar Ahuja, and Haribabu Kommi, and me.
* btree: Support parallel index scans.Robert Haas2017-02-15
| | | | | | | | | | | | | This isn't exposed to the optimizer or the executor yet; we'll add support for those things in a separate patch. But this puts the basic mechanism in place: several processes can attach to a parallel btree index scan, and each one will get a subset of the tuples that would have been produced by a non-parallel scan. Each index page becomes the responsibility of a single worker, which then returns all of the TIDs on that page. Rahila Syed, Amit Kapila, Robert Haas, reviewed and tested by Anastasia Lubennikova, Tushar Ahuja, and Haribabu Kommi.
* Split index xlog headers from other private index headers.Robert Haas2017-02-14
| | | | | | | | | | | | | The xlog-specific headers need to be included in both frontend code - specifically, pg_waldump - and the backend, but the remainder of the private headers for each index are only needed by the backend. By splitting the xlog stuff out into separate headers, pg_waldump pulls in fewer backend headers, which is a good thing. Patch by me, reviewed by Michael Paquier and Andres Freund, per a complaint from Dilip Kumar. Discussion: http://postgr.es/m/CA+TgmoZ=F=GkxV0YEv-A8tb+AEGy_Qa7GSiJ8deBKFATnzfEug@mail.gmail.com
* Minor fixes for WAL consistency checking.Robert Haas2017-02-14
| | | | | | Michael Paquier, reviewed and slightly revised by me. Discussion: http://postgr.es/m/CAB7nPqRzCQb=vdfHvMtP0HMLBHU6z1aGdo4GJsUP-HP8jx+Pkw@mail.gmail.com
* Rename dtrace probes for ongoing xlog -> wal conversion.Robert Haas2017-02-09
| | | | xlog-switch becomes wal-switch, and xlog-insert becomes wal-insert.
* Rename user-facing tools with "xlog" in the name to say "wal".Robert Haas2017-02-09
| | | | | This means pg_receivexlog because pg_receivewal, pg_resetxlog becomes pg_resetwal, and pg_xlogdump becomes pg_waldump.
* Remove all references to "xlog" from SQL-callable functions in pg_proc.Robert Haas2017-02-09
| | | | | | | | | | | | | | Commit f82ec32ac30ae7e3ec7c84067192535b2ff8ec0e renamed the pg_xlog directory to pg_wal. To make things consistent, and because "xlog" is terrible terminology for either "transaction log" or "write-ahead log" rename all SQL-callable functions that contain "xlog" in the name to instead contain "wal". (Note that this may pose an upgrade hazard for some users.) Similarly, rename the xlog_position argument of the functions that create slots to be called wal_position. Discussion: https://www.postgresql.org/message-id/CA+Tgmob=YmA=H3DbW1YuOXnFVgBheRmyDkWcD9M8f=5bGWYEoQ@mail.gmail.com
* pageinspect: Fix hash_bitmap_info not to read the underlying page.Robert Haas2017-02-09
| | | | | | | | | | | | It did that to verify that the page was an overflow page rather than anything else, but that means that checking the status of all the overflow bits requires reading the entire index. So don't do that. The new code validates that the page is not a primary bucket page or bitmap page by looking at the metapage, so that using this on large numbers of pages can be reasonably efficient. Ashutosh Sharma, per a complaint from me, and with further modifications by me.
* Allow index AMs to cache data across aminsert calls within a SQL command.Tom Lane2017-02-09
| | | | | | | | | | | | | | | | | | | | | | | | | | It's always been possible for index AMs to cache data across successive amgettuple calls within a single SQL command: the IndexScanDesc.opaque field is meant for precisely that. However, no comparable facility exists for amortizing setup work across successive aminsert calls. This patch adds such a feature and teaches GIN, GIST, and BRIN to use it to amortize catalog lookups they'd previously been doing on every call. (The other standard index AMs keep everything they need in the relcache, so there's little to improve there.) For GIN, the overall improvement in a statement that inserts many rows can be as much as 10%, though it seems a bit less for the other two. In addition, this makes a really significant difference in runtime for CLOBBER_CACHE_ALWAYS tests, since in those builds the repeated catalog lookups are vastly more expensive. The reason this has been hard up to now is that the aminsert function is not passed any useful place to cache per-statement data. What I chose to do is to add suitable fields to struct IndexInfo and pass that to aminsert. That's not widening the index AM API very much because IndexInfo is already within the ken of ambuild; in fact, by passing the same info to aminsert as to ambuild, this is really removing an inconsistency in the AM API. Discussion: https://postgr.es/m/27568.1486508680@sss.pgh.pa.us
* Add WAL consistency checking facility.Robert Haas2017-02-08
| | | | | | | | | | | | | | When the new GUC wal_consistency_checking is set to a non-empty value, it triggers recording of additional full-page images, which are compared on the standby against the results of applying the WAL record (without regard to those full-page images). Allowable differences such as hints are masked out, and the resulting pages are compared; any difference results in a FATAL error on the standby. Kuntal Ghosh, based on earlier patches by Michael Paquier and Heikki Linnakangas. Extensively reviewed and revised by Michael Paquier and by me, with additional reviews and comments from Amit Kapila, Álvaro Herrera, Simon Riggs, and Peter Eisentraut.
* Fix compiler warning.Robert Haas2017-02-07
| | | | Mithun Cy, per a report by Erik Rijkers
* Cache hash index's metapage in rel->rd_amcache.Robert Haas2017-02-07
| | | | | | | | | | | | | | | | | | | | | | | This avoids a very significant amount of buffer manager traffic and contention when scanning hash indexes, because it's no longer necessary to lock and pin the metapage for every scan. We do need some way of figuring out when the cache is too stale to use any more, so that when we lock the primary bucket page to which the cached metapage points us, we can tell whether a split has occurred since we cached the metapage data. To do that, we use the hash_prevblkno field in the primary bucket page, which would otherwise always be set to InvalidBuffer. This patch contains code so that it will continue working (although less efficiently) with hash indexes built before this change, but perhaps we should consider bumping the hash version and ripping out the compatibility code. That decision can be made later, though. Mithun Cy, reviewed by Jesper Pedersen, Amit Kapila, and by me. Before committing, I made a number of cosmetic changes to the last posted version of the patch, adjusted _hash_getcachedmetap to be more careful about order of operation, and made some necessary updates to the pageinspect documentation and regression tests.
* Fix typos in comments.Heikki Linnakangas2017-02-06
| | | | | | | | | Backpatch to all supported versions, where applicable, to make backpatching of future fixes go more smoothly. Josh Soref Discussion: https://www.postgresql.org/message-id/CACZqfqCf+5qRztLPgmmosr-B0Ye4srWzzw_mo4c_8_B_mtjmJQ@mail.gmail.com
* Improve grammar of message about two-phase state files.Robert Haas2017-02-03
| | | | | | | | | | When there's only one two-phase state file, there's also only one long-running prepared transaction. Adjust the message text accordingly. Nikhil Sontakke Discussion: http://postgr.es/m/CAMGcDxcmR_DWZXXndGoPzVQx=B17A5=RviEA1qNaF=FWLy5Whw@mail.gmail.com
* pageinspect: Support hash indexes.Robert Haas2017-02-02
| | | | | | | | | Patch by Jesper Pedersen and Ashutosh Sharma, with some error handling improvements by me. Tests from Peter Eisentraut. Reviewed by Álvaro Herrera, Michael Paquier, Jesper Pedersen, Jeff Janes, Peter Eisentraut, Amit Kapila, Mithun Cy, and me. Discussion: http://postgr.es/m/e2ac6c58-b93f-9dd9-f4e6-d6d30add7fdf@redhat.com
* Don't count background workers against a user's connection limit.Andrew Dunstan2017-02-01
| | | | | | | | | | Doing so doesn't seem to be within the purpose of the per user connection limits, and has particularly unfortunate effects in conjunction with parallel queries. Backpatch to 9.6 where parallel queries were introduced. David Rowley, reviewed by Robert Haas and Albe Laurenz.
* Refactor other replication commands to use DestRemoteSimple.Robert Haas2017-02-01
| | | | | | | | | | | | Commit a84069d9350400c860d5e932b50dfd337aa407b0 added a new type of DestReceiver to avoid duplicating the existing code for the SHOW command, but it turns out we can leverage that new DestReceiver type in a few more places, saving some code. Michael Paquier, reviewed by Andres Freund and by me. Discussion: http://postgr.es/m/CAB7nPqSdFOQC0evc0r1nJeQyGBqjBrR41MC4rcMqUUpoJaZbtQ%40mail.gmail.com Discussion: http://postgr.es/m/CAB7nPqT2K4XFT1JgqufFBjsOc-NUKXg5qBDucHPMbk6Xi1kYaA@mail.gmail.com
* Move comment about test slightly closer to test.Robert Haas2017-01-31
| | | | | | | | The addition of a TestForOldSnapshot() call here has made the referent of this comment slightly less clear, so move the comment to compensate. Amit Kapila (as part of the parallel index scan patch)
* Be more aggressive in avoiding tuple conversion.Robert Haas2017-01-24
| | | | | | | | | | | | | | | | | | | | | | According to the comments in tupconvert.c, it's necessary to perform tuple conversion when either table has OIDs, and this was previously checked by ensuring that the tdtypeid value matched between the tables in question. However, that's overly stringent: we have access to tdhasoid and can test directly whether OIDs are present, which lets us avoid conversion in cases where the type OIDs are different but the tuple descriptors are entirely the same (and neither has OIDs). This is useful to the partitioning code, which can thereby avoid converting tuples when inserting into a partition whose columns appear in the same order as the parent columns, the normal case. It's possible for the tuple routing code to avoid some additional overhead in this case as well, so do that, too. It's not clear whether it would be OK to skip this when both tables have OIDs: do callers count on this to build a new tuple (losing the previous OID) in such instances? Until we figure it out, leave the behavior in that case alone. Amit Langote, reviewed by me.
* Add a SHOW command to the replication command language.Robert Haas2017-01-24
| | | | | | | | | | | | | | This is useful infrastructure for an upcoming proposed patch to allow the WAL segment size to be changed at initdb time; tools like pg_basebackup need the ability to interrogate the server setting. But it also doesn't seem like a bad thing to have independently of that; it may find other uses in the future. Robert Haas and Beena Emerson. (The original patch here was by Beena, but I rewrote it to such a degree that most of the code being committed here is mine.) Discussion: http://postgr.es/m/CA+TgmobNo4qz06wHEmy9DszAre3dYx-WNhHSCbU9SAwf+9Ft6g@mail.gmail.com
* Add a new DestReceiver for printing tuples without catalog access.Robert Haas2017-01-24
| | | | | | | | | | | | | | | If you create a DestReciver of type DestRemote and try to use it from a replication connection that is not bound to a specific daabase, or any other hypothetical type of backend that is not bound to a specific database, it will fail because it doesn't have a pg_proc catalog to look up properties of the types being printed. In general, that's an unavoidable problem, but we can hardwire the properties of a few builtin types in order to support utility commands. This new DestReceiver of type DestRemoteSimple does just that. Patch by me, reviewed by Michael Paquier. Discussion: http://postgr.es/m/CA+TgmobNo4qz06wHEmy9DszAre3dYx-WNhHSCbU9SAwf+9Ft6g@mail.gmail.com
* Extend index AM API for parallel index scans.Robert Haas2017-01-24
| | | | | | | This patch doesn't actually make any index AM parallel-aware, but it provides the necessary functions at the AM layer to do so. Rahila Syed, Amit Kapila, Robert Haas
* Fix interaction of partitioned tables with BulkInsertState.Robert Haas2017-01-24
| | | | | | | | | | | | | | | | | | | | When copying into a partitioned table, the target heap may change from one tuple to next. We must ask ReadBufferBI() to get a new buffer every time such change occurs. To do that, use new function ReleaseBulkInsertStatePin(). This fixes the bug that tuples ended up being inserted into the wrong partition, which occurred exactly because the wrong buffer was used. Amit Langote, per a suggestion from Robert Haas. Some cosmetic adjustments by me. Reports by 高增琦 (Gao Zengqi), Venkata B Nagothi, and Ragnar Ouchterlony. Discussion: http://postgr.es/m/CAFmBtr32FDOqofo8yG-4mjzL1HnYHxXK5S9OGFJ%3D%3DcJpgEW4vA%40mail.gmail.com Discussion: http://postgr.es/m/CAEyp7J9WiX0L3DoiNcRrY-9iyw%3DqP%2Bj%3DDLsAnNFF1xT2J1ggfQ%40mail.gmail.com Discussion: http://postgr.es/m/16d73804-c9cd-14c5-463e-5caad563ff77%40agama.tv Discussion: http://postgr.es/m/CA+TgmoaiZpDVUUN8LZ4jv1qFE_QyR+H9ec+79f5vNczYarg5Zg@mail.gmail.com
* Move some things from builtins.h to new header filesPeter Eisentraut2017-01-20
| | | | This avoids that builtins.h has to include additional header files.
* Logical replicationPeter Eisentraut2017-01-20
| | | | | | | | | | | | | - Add PUBLICATION catalogs and DDL - Add SUBSCRIPTION catalog and DDL - Define logical replication protocol and output plugin - Add logical replication workers From: Petr Jelinek <petr@2ndquadrant.com> Reviewed-by: Steve Singer <steve@ssinger.info> Reviewed-by: Andres Freund <andres@anarazel.de> Reviewed-by: Erik Rijkers <er@xs4all.nl> Reviewed-by: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
* Fix race condition in reading commit timestampsAlvaro Herrera2017-01-19
| | | | | | | | | | | | | | | | | | | | | | | | | If a user requests the commit timestamp for a transaction old enough that its data is concurrently being truncated away by vacuum at just the right time, they would receive an ugly internal file-not-found error message from slru.c rather than the expected NULL return value. In a primary server, the window for the race is very small: the lookup has to occur exactly between the two calls by vacuum, and there's not a lot that happens between them (mostly just a multixact truncate). In a standby server, however, the window is larger because the truncation is executed as soon as the WAL record for it is replayed, but the advance of the oldest-Xid is not executed until the next checkpoint record. To fix in the primary, simply reverse the order of operations in vac_truncate_clog. To fix in the standby, augment the WAL truncation record so that the standby is aware of the new oldest-XID value and can apply the update immediately. WAL version bumped because of this. No backpatch, because of the low importance of the bug and its rarity. Author: Craig Ringer Reviewed-By: Petr Jelínek, Peter Eisentraut Discussion: https://postgr.es/m/CAMsr+YFhVtRQT1VAwC+WGbbxZZRzNou=N9Ed-FrCqkwQ8H8oJQ@mail.gmail.com
* Improve comment in hashsearch.c.Robert Haas2017-01-18
| | | | Typo fix from Mithun Cy; other improvements by me.
* Generate fmgr prototypes automaticallyPeter Eisentraut2017-01-17
| | | | | | | | | | | | Gen_fmgrtab.pl creates a new file fmgrprotos.h, which contains prototypes for all functions registered in pg_proc.h. This avoids having to manually maintain these prototypes across a random variety of header files. It also automatically enforces a correct function signature, and since there are warnings about missing prototypes, it will detect functions that are defined but not registered in pg_proc.h (or otherwise used). Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
* Fix an assertion failure related to an exclusive backup.Fujii Masao2017-01-17
| | | | | | | | | | | | | | | | | | | | | | Previously multiple sessions could execute pg_start_backup() and pg_stop_backup() to start and stop an exclusive backup at the same time. This could trigger the assertion failure of "FailedAssertion("!(XLogCtl->Insert.exclusiveBackup)". This happend because, even while pg_start_backup() was starting an exclusive backup, other session could run pg_stop_backup() concurrently and mark the backup as not-in-progress unconditionally. This patch introduces ExclusiveBackupState indicating the state of an exclusive backup. This state is used to ensure that there is only one session running pg_start_backup() or pg_stop_backup() at the same time, to avoid the assertion failure. Back-patch to all supported versions. Author: Michael Paquier Reviewed-By: Kyotaro Horiguchi and me Reported-By: Andreas Seltenreich Discussion: <87mvktojme.fsf@credativ.de>
* Improve coding in _hash_addovflpage.Robert Haas2017-01-10
| | | | | | | | Instead of relying on the page contents to know whether we have advanced from the primary bucket page to an overflow page, track that explicitly. Amit Kapila, per a complaint by me.
* Fix ALTER TABLE / SET TYPE for irregular inheritanceAlvaro Herrera2017-01-09
| | | | | | | | | | | | | | | | | | | If inherited tables don't have exactly the same schema, the USING clause in an ALTER TABLE / SET DATA TYPE misbehaves when applied to the children tables since commit 9550e8348b79. Starting with that commit, the attribute numbers in the USING expression are fixed during parse analysis. This can lead to bogus errors being reported during execution, such as: ERROR: attribute 2 has wrong type DETAIL: Table has type smallint, but query expects integer. Since it wouldn't do to revert to the original coding, we now apply a transformation to map the attribute numbers to the correct ones for each child. Reported by Justin Pryzby Analysis by Tom Lane; patch by me. Discussion: https://postgr.es/m/20170102225618.GA10071@telsasoft.com
* BRIN revmap pages are not standard pages ...Alvaro Herrera2017-01-09
| | | | | | | | | | | | | | | | | | | | | | | | ... and therefore we ought not to tell XLogRegisterBuffer the opposite, when writing XLog for a brin update that moves the index tuple to a different page. Otherwise, xlog insertion would try to "compress the hole" when producing a full-page image for it; but since we don't update pd_lower/upper, the hole covers the whole page. On WAL replay, the revmap page becomes empty and so the entire portion of the index is useless and needs to be recomputed. This is low-probability: a BRIN update only moves an index tuple to a different page when the summary tuple is larger than the existing one, which doesn't happen with fixed-width datatypes. Also, the revmap page must be first after a checkpoint. Report and patch: Kuntal Ghosh Bug is alleged to have detected by a WAL-consistency-checking tool. Discussion: https://postgr.es/m/CAGz5QCJ=00UQjScSEFbV=0qO5ShTZB9WWz_Fm7+Wd83zPs9Geg@mail.gmail.com I posted a test case demonstrating the problem, but I'm refraining from adding it to the test suite; if the WAL consistency tool makes it in, that will be a better way to catch this from regressing. (We should definitely have someting that causes not-same-page updates, though.)
* Update copyright via script for 2017Bruce Momjian2017-01-03
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* Remove triggerable Assert in hashname().Tom Lane2016-12-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | hashname() asserted that the key string it is given is shorter than NAMEDATALEN. That should surely always be true if the input is in fact a regular value of type "name". However, for reasons of coding convenience, we allow plain old C strings to be treated as "name" values in many places. Some SQL functions accept arbitrary "text" inputs, convert them to C strings, and pass them otherwise-untransformed to syscache lookups for name columns, allowing an overlength input value to trigger hashname's Assert. This would be a DOS problem, except that it only happens in assert-enabled builds which aren't recommended for production. In a production build, you'll just get a name lookup error, since regardless of the hash value computed by hashname, the later equality comparison checks can't match. Likewise, if the catalog lookup is done by seqscan or indexscan searches, there will just be a lookup error, since the name comparison functions don't contain any similar length checks, and will see an overlength input as unequal to any stored entry. After discussion we concluded that we should simply remove this Assert. It's inessential to hashname's own functionality, and having such an assertion in only some paths for name lookup is more of a foot-gun than a useful check. There may or may not be a case for the affected callers to do something other than let the name lookup fail, but we'll consider that separately; in any case we probably don't want to change such behavior in the back branches. Per report from Tushar Ahuja. Back-patch to all supported branches. Report: https://postgr.es/m/7d0809ee-6f25-c9d6-8e74-5b2967830d49@enterprisedb.com Discussion: https://postgr.es/m/17691.1482523168@sss.pgh.pa.us
* Remove _hash_chgbufaccess().Robert Haas2016-12-23
| | | | | | | | | This is basically for the same reasons I got rid of _hash_wrtbuf() in commit 25216c98938495fd741bf585dcbef45b3a9ffd40: it's not convenient to have a function which encapsulates MarkBufferDirty(), especially as we move towards having hash indexes be WAL-logged. Patch by me, reviewed (but not entirely endorsed) by Amit Kapila.
* Skip checkpoints, archiving on idle systems.Andres Freund2016-12-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Some background activity (like checkpoints, archive timeout, standby snapshots) is not supposed to happen on an idle system. Unfortunately so far it was not easy to determine when a system is idle, which defeated some of the attempts to avoid redundant activity on an idle system. To make that easier, allow to make individual WAL insertions as not being "important". By checking whether any important activity happened since the last time an activity was performed, it now is easy to check whether some action needs to be repeated. Use the new facility for checkpoints, archive timeout and standby snapshots. The lack of a facility causes some issues in older releases, but in my opinion the consequences (superflous checkpoints / archived segments) aren't grave enough to warrant backpatching. Author: Michael Paquier, editorialized by Andres Freund Reviewed-By: Andres Freund, David Steele, Amit Kapila, Kyotaro HORIGUCHI Bug: #13685 Discussion: https://www.postgresql.org/message-id/20151016203031.3019.72930@wrigleys.postgresql.org https://www.postgresql.org/message-id/CAB7nPqQcPqxEM3S735Bd2RzApNqSNJVietAC=6kfkYv_45dKwA@mail.gmail.com Backpatch: -
* Fix broken error check in _hash_doinsert.Robert Haas2016-12-22
| | | | | | | | | | | | You can't just cast a HashMetaPage to a Page, because the meta page data is stored after the page header, not at offset 0. Fortunately, this didn't break anything because it happens to find hashm_bsize at the offset at which it expects to find pd_pagesize_version, and the values are close enough to the same that this works out. Still, it's a bug, so back-patch to all supported versions. Mithun Cy, revised a bit by me.
* Fix locking problem in _hash_squeezebucket() / _hash_freeovflpage().Robert Haas2016-12-19
| | | | | | | | | | | | A bucket squeeze operation needs to lock each page of the bucket before releasing the prior page, but the previous coding fumbled the locking when freeing an overflow page during a bucket squeeze operation. Commit 6d46f4783efe457f74816a75173eb23ed8930020 introduced this bug. Amit Kapila, with help from Kuntal Ghosh and Dilip Kumar, after an initial trouble report by Jeff Janes. Reviewed by me. I also fixed a problem with a comment.
* Simplify LWLock tranche machinery by removing array_base/array_stride.Robert Haas2016-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | array_base and array_stride were added so that we could identify the offset of an LWLock within a tranche, but this facility is only very marginally used apart from the main tranche. So, give every lock in the main tranche its own tranche ID and get rid of array_base, array_stride, and all that's attached. For debugging facilities (Trace_lwlocks and LWLOCK_STATS) print the pointer address of the LWLock using %p instead of the offset. This is arguably more useful, and certainly a lot cheaper. Drop the offset-within-tranche from the information reported to dtrace and from one can't-happen message inside lwlock.c. The main user-visible impact of this change is that pg_stat_activity will now report all waits for LWLocks as "LWLock" rather than reporting some as "LWLockTranche" and others as "LWLockNamed". The main motivation for this change is that the need to specify an array_base and an array_stride is awkward for parallel query. There is only a very limited supply of tranche IDs so we can't just keep allocating new ones, and if we try to use the same tranche IDs every time then we run into trouble when multiple parallel contexts are use simultaneously. So if we didn't get rid of this mechanism we'd have to make it even more complicated. By simplifying it in this way, we instead reduce the size of the generated code for lwlock.c by about 5%. Discussion: http://postgr.es/m/CA+TgmoYsFn6NUW1x0AZtupJGUAs1UDY4dJtCN47_Q6D0sP80PA@mail.gmail.com
* Fix more hash index bugs around marking buffers dirty.Robert Haas2016-12-16
| | | | | | | | | | | | | | In _hash_freeovflpage(), if we're freeing the overflow page that immediate follows the page to which tuples are being moved (the confusingly-named "write buffer"), don't forget to mark that page dirty after updating its hasho_nextblkno. In _hash_squeezebucket(), it's not necessary to mark the primary bucket page dirty if there are no overflow pages, because there's nothing to squeeze in that case. Amit Kapila, with help from Kuntal Ghosh and Dilip Kumar, after an initial trouble report by Jeff Janes.