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* Use group updates when setting transaction status in clog.Robert Haas2017-09-01
| | | | | | | | | | | | | | | Commit 0e141c0fbb211bdd23783afa731e3eef95c9ad7a introduced a mechanism to reduce contention on ProcArrayLock by having a single process clear XIDs in the procArray on behalf of multiple processes, reducing the need to hand the lock around. A previous attempt to introduce a similar mechanism for CLogControlLock in ccce90b398673d55b0387b3de66639b1b30d451b crashed and burned, but the design problem which resulted in those failures is believed to have been corrected in this version. Amit Kapila, with some cosmetic changes by me. See the previous commit message for additional credits. Discussion: http://postgr.es/m/CAA4eK1KudxzgWhuywY_X=yeSAhJMT4DwCjroV5Ay60xaeB2Eew@mail.gmail.com
* Introduce 64-bit hash functions with a 64-bit seed.Robert Haas2017-08-31
| | | | | | | | | | | | | | | | This will be useful for hash partitioning, which needs a way to seed the hash functions to avoid problems such as a hash index on a hash partitioned table clumping all values into a small portion of the bucket space; it's also useful for anything that wants a 64-bit hash value rather than a 32-bit hash value. Just in case somebody wants a 64-bit hash value that is compatible with the existing 32-bit hash values, make the low 32-bits of the 64-bit hash value match the 32-bit hash value when the seed is 0. Robert Haas and Amul Sul Discussion: http://postgr.es/m/CA+Tgmoafx2yoJuhCQQOL5CocEi-w_uG4S2xT0EtgiJnPGcHW3g@mail.gmail.com
* Clean up shm_mq cleanup.Tom Lane2017-08-31
| | | | | | | | | | | | | | | | | | | | | | | | | The logic around shm_mq_detach was a few bricks shy of a load, because (contrary to the comments for shm_mq_attach) all it did was update the shared shm_mq state. That left us leaking a bit of process-local memory, but much worse, the on_dsm_detach callback for shm_mq_detach was still armed. That means that whenever we ultimately detach from the DSM segment, we'd run shm_mq_detach again for already-detached, possibly long-dead queues. This accidentally fails to fail today, because we only ever re-use a shm_mq's memory for another shm_mq, and multiple detach attempts on the last such shm_mq are fairly harmless. But it's gonna bite us someday, so let's clean it up. To do that, change shm_mq_detach's API so it takes a shm_mq_handle not the underlying shm_mq. This makes the callers simpler in most cases anyway. Also fix a few places in parallel.c that were just pfree'ing the handle structs rather than doing proper cleanup. Back-patch to v10 because of the risk that the revenant shm_mq_detach callbacks would cause a live bug sometime. Since this is an API change, it's too late to do it in 9.6. (We could make a variant patch that preserves API, but I'm not excited enough to do that.) Discussion: https://postgr.es/m/8670.1504192177@sss.pgh.pa.us
* Separate reinitialization of shared parallel-scan state from ExecReScan.Tom Lane2017-08-30
| | | | | | | | | | | | | | | | | | | | | | | | | | Previously, the parallel executor logic did reinitialization of shared state within the ExecReScan code for parallel-aware scan nodes. This is problematic, because it means that the ExecReScan call has to occur synchronously (ie, during the parent Gather node's ReScan call). That is swimming very much against the tide so far as the ExecReScan machinery is concerned; the fact that it works at all today depends on a lot of fragile assumptions, such as that no plan node between Gather and a parallel-aware scan node is parameterized. Another objection is that because ExecReScan might be called in workers as well as the leader, hacky extra tests are needed in some places to prevent unwanted shared-state resets. Hence, let's separate this code into two functions, a ReInitializeDSM call and the ReScan call proper. ReInitializeDSM is called only in the leader and is guaranteed to run before we start new workers. ReScan is returned to its traditional function of resetting only local state, which means that ExecReScan's usual habits of delaying or eliminating child rescan calls are safe again. As with the preceding commit 7df2c1f8d, it doesn't seem to be necessary to make these changes in 9.6, which is a good thing because the FDW and CustomScan APIs are impacted. Discussion: https://postgr.es/m/CAA4eK1JkByysFJNh9M349u_nNjqETuEnY_y1VUc_kJiU0bxtaQ@mail.gmail.com
* Refactor typcache.c's record typmod hash table.Andres Freund2017-08-22
| | | | | | | | | | | | | | | | Previously, tuple descriptors were stored in chains keyed by a fixed size array of OIDs. That meant there were effectively two levels of collision chain -- one inside and one outside the hash table. Instead, let dynahash.c look after conflicts for us by supplying a proper hash and equal function pair. This is a nice cleanup on its own, but also simplifies followup changes allowing blessed TupleDescs to be shared between backends participating in parallel query. Author: Thomas Munro Reviewed-By: Andres Freund Discussion: https://postgr.es/m/CAEepm%3D34GVhOL%2BarUx56yx7OPk7%3DqpGsv3CpO54feqjAwQKm5g%40mail.gmail.com
* Partially flatten struct tupleDesc so that it can be used in DSM.Andres Freund2017-08-20
| | | | | | | | | | | | | TupleDesc's attributes were already stored in contiguous memory after the struct. Go one step further and get rid of the array of pointers to attributes so that they can be stored in shared memory mapped at different addresses in each backend. This won't work for TupleDescs with contraints and defaults, since those point to other objects, but for many purposes only attributes are needed. Author: Thomas Munro Reviewed-By: Andres Freund Discussion: https://postgr.es/m/CAEepm=0ZtQ-SpsgCyzzYpsXS6e=kZWqk3g5Ygn3MDV7A8dabUA@mail.gmail.com
* Change tupledesc->attrs[n] to TupleDescAttr(tupledesc, n).Andres Freund2017-08-20
| | | | | | | | | | | This is a mechanical change in preparation for a later commit that will change the layout of TupleDesc. Introducing a macro to abstract the details of where attributes are stored will allow us to change that in separate step and revise it in future. Author: Thomas Munro, editorialized by Andres Freund Reviewed-By: Andres Freund Discussion: https://postgr.es/m/CAEepm=0ZtQ-SpsgCyzzYpsXS6e=kZWqk3g5Ygn3MDV7A8dabUA@mail.gmail.com
* Fix pg_atomic_u64 initialization.Heikki Linnakangas2017-08-17
| | | | | | | | | As Andres pointed out, pg_atomic_init_u64 must be used to initialize an atomic variable, before it can be accessed with the actual atomic ops. Trying to use pg_atomic_write_u64 on an uninitialized variable leads to a failure with the fallback implementation that uses a spinlock. Discussion: https://www.postgresql.org/message-id/20170816191346.d3ke5tpshhco4bnd%40alap3.anarazel.de
* Use atomic ops to hand out pages to scan in parallel scan.Heikki Linnakangas2017-08-16
| | | | | | | | | | With a lot of CPUs, the spinlock that protects the current scan location in a parallel scan can become a bottleneck. Use an atomic fetch-and-add instruction instead. David Rowley Discussion: https://www.postgresql.org/message-id/CAKJS1f9tgsPhqBcoPjv9_KUPZvTLCZ4jy%3DB%3DbhqgaKn7cYzm-w@mail.gmail.com
* Remove dedicated B-tree root-split record types.Heikki Linnakangas2017-08-16
| | | | | | | | | | | | | | Since commit 40dae7ec53, which changed the way b-tree page splitting works, there has been no difference in the handling of root, and non-root split WAL records. We don't need to distinguish them anymore If you're worried about the loss of debugging information, note that usually a root split record will normally be followed by a WAL record to create the new root page. The root page will also have the BTP_ROOT flag set on the page itself, and there is a pointer to it from the metapage. Author: Aleksander Alekseev Discussion: https://www.postgresql.org/message-id/20170406122116.GA11081@e733.localdomain
* Final pgindent + perltidy run for v10.Tom Lane2017-08-14
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* Handle elog(FATAL) during ROLLBACK more robustly.Tom Lane2017-08-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Stress testing by Andreas Seltenreich disclosed longstanding problems that occur if a FATAL exit (e.g. due to receipt of SIGTERM) occurs while we are trying to execute a ROLLBACK of an already-failed transaction. In such a case, xact.c is in TBLOCK_ABORT state, so that AbortOutOfAnyTransaction would skip AbortTransaction and go straight to CleanupTransaction. This led to an assert failure in an assert-enabled build (due to the ROLLBACK's portal still having a cleanup hook) or without assertions, to a FATAL exit complaining about "cannot drop active portal". The latter's not disastrous, perhaps, but it's messy enough to want to improve it. We don't really want to run all of AbortTransaction in this code path. The minimum required to clean up the open portal safely is to do AtAbort_Memory and AtAbort_Portals. It seems like a good idea to do AtAbort_Memory unconditionally, to be entirely sure that we are starting with a safe CurrentMemoryContext. That means that if the main loop in AbortOutOfAnyTransaction does nothing, we need an extra step at the bottom to restore CurrentMemoryContext = TopMemoryContext, which I chose to do by invoking AtCleanup_Memory. This'll result in calling AtCleanup_Memory twice in many of the paths through this function, but that seems harmless and reasonably inexpensive. The original motivation for the assertion in AtCleanup_Portals was that we wanted to be sure that any user-defined code executed as a consequence of the cleanup hook runs during AbortTransaction not CleanupTransaction. That still seems like a valid concern, and now that we've seen one case of the assertion firing --- which means that exactly that would have happened in a production build --- let's replace the Assert with a runtime check. If we see the cleanup hook still set, we'll emit a WARNING and just drop the hook unexecuted. This has been like this a long time, so back-patch to all supported branches. Discussion: https://postgr.es/m/877ey7bmun.fsf@ansel.ydns.eu
* Remove AtEOXact_CatCache().Tom Lane2017-08-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The sole useful effect of this function, to check that no catcache entries have positive refcounts at transaction end, has really been obsolete since we introduced ResourceOwners in PG 8.1. We reduced the checks to assertions years ago, so that the function was a complete no-op in production builds. There have been previous discussions about removing it entirely, but consensus up to now was that it had some small value as a cross-check for bugs in the ResourceOwner logic. However, it now emerges that it's possible to trigger these assertions if you hit an assert-enabled backend with SIGTERM during a call to SearchCatCacheList, because that function temporarily increases the refcounts of entries it's intending to add to a catcache list construct. In a normal ERROR scenario, the extra refcounts are cleaned up by SearchCatCacheList's PG_CATCH block; but in a FATAL exit we do a transaction abort and exit without ever executing PG_CATCH handlers. There's a case to be made that this is a generic hazard and we should consider restructuring elog(FATAL) handling so that pending PG_CATCH handlers do get run. That's pretty scary though: it could easily create more problems than it solves. Preliminary stress testing by Andreas Seltenreich suggests that there are not many live problems of this ilk, so we rejected that idea. There are more-localized ways to fix the problem; the most principled one would be to use PG_ENSURE_ERROR_CLEANUP instead of plain PG_TRY. But adding cycles to SearchCatCacheList isn't very appealing. We could also weaken the assertions in AtEOXact_CatCache in some more or less ad-hoc way, but that just makes its raison d'etre even less compelling. In the end, the most reasonable solution seems to be to just remove AtEOXact_CatCache altogether, on the grounds that it's not worth trying to fix it. It hasn't found any bugs for us in many years. Per report from Jeevan Chalke. Back-patch to all supported branches. Discussion: https://postgr.es/m/CAM2+6=VEE30YtRQCZX7_sCFsEpoUkFBV1gZazL70fqLn8rcvBA@mail.gmail.com
* Remove uses of "slave" in replication contextsPeter Eisentraut2017-08-10
| | | | | This affects mostly code comments, some documentation, and tests. Official APIs already used "standby".
* Remove incorrect assertion in clog.cRobert Haas2017-08-10
| | | | | | | | | | | We must advance the oldest XID that can be safely looked up in clog *before* truncating CLOG, and the oldest XID that can't be reused *after* truncating CLOG. This assertion, and the accompanying comment, are confused; remove them. Reported by Neha Sharma. Discussion: http://postgr.es/m/CANiYTQumC3T=UMBMd1Hor=5XWZYuCEQBioL3ug0YtNQCMMT5wQ@mail.gmail.com
* Reword some unclear commentsAlvaro Herrera2017-08-08
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* Make pg_stop_backup's wait_for_archive flag work on standbys.Robert Haas2017-08-05
| | | | | | | | | | | | Previously, it had no effect. Now, if archive_mode=always, it will work, and if not, you'll get a warning. Masahiko Sawada, Michael Paquier, and Robert Haas. The patch as submitted also changed the behavior so that we would write and remove history files on standbys, but that seems like material for a separate patch to me. Discussion: http://postgr.es/m/CAD21AoC2Xw6M=ZJyejq_9d_iDkReC_=rpvQRw5QsyzKQdfYpkw@mail.gmail.com
* Only kill sync workers at commit time in subscription DDLPeter Eisentraut2017-08-04
| | | | | | This allows a transaction abort to avoid killing those workers. Author: Petr Jelinek <petr.jelinek@2ndquadrant.com>
* hash: Immediately after a bucket split, try to clean the old bucket.Robert Haas2017-08-04
| | | | | | | | | | | | If it works, then we won't be storing two copies of all the tuples that were just moved. If not, VACUUM will still take care of it eventually. Per a report from AP and analysis from Amit Kapila, it seems that a bulk load can cause splits fast enough that VACUUM won't deal with the problem in time to prevent bloat. Amit Kapila; I rewrote the comment. Discussion: http://postgr.es/m/20170704105728.mwb72jebfmok2nm2@zip.com.au
* Fix concurrent locking of tuple update chainAlvaro Herrera2017-07-26
| | | | | | | | | | | | | | | | | | | If several sessions are concurrently locking a tuple update chain with nonconflicting lock modes using an old snapshot, and they all succeed, it may happen that some of them fail because of restarting the loop (due to a concurrent Xmax change) and getting an error in the subsequent pass while trying to obtain a tuple lock that they already have in some tuple version. This can only happen with very high concurrency (where a row is being both updated and FK-checked by multiple transactions concurrently), but it's been observed in the field and can have unpleasant consequences such as an FK check failing to see a tuple that definitely exists: ERROR: insert or update on table "child_table" violates foreign key constraint "fk_constraint_name" DETAIL: Key (keyid)=(123456) is not present in table "parent_table". (where the key is observably present in the table). Discussion: https://postgr.es/m/20170714210011.r25mrff4nxjhmf3g@alvherre.pgsql
* Fix double shared memory allocation.Teodor Sigaev2017-07-21
| | | | | | | | | | | SLRU buffer lwlocks are allocated twice by oversight in commit fe702a7b3f9f2bc5bf6d173166d7d55226af82c8 where that locks were moved to separate tranche. The bug doesn't have user-visible effects except small overspending of shared memory. Backpatch to 9.6 where it was introduced. Alexander Korotkov with small editorization by me.
* Add static assertions about pg_control fitting into one disk sector.Tom Lane2017-07-19
| | | | | | | | | | | | | | | | | When pg_control was first designed, sizeof(ControlFileData) was small enough that a comment seemed like plenty to document the assumption that it'd fit into one disk sector. Now it's nearly 300 bytes, raising the possibility that somebody would carelessly add enough stuff to create a problem. Let's add a StaticAssertStmt() to ensure that the situation doesn't pass unnoticed if it ever occurs. While at it, rename PG_CONTROL_SIZE to PG_CONTROL_FILE_SIZE to make it clearer what that symbol means, and convert the existing runtime comparisons of sizeof(ControlFileData) vs. PG_CONTROL_FILE_SIZE to be static asserts --- we didn't have that technology when this code was first written. Discussion: https://postgr.es/m/9192.1500490591@sss.pgh.pa.us
* hash: Fix write-ahead logging bugs related to init forks.Robert Haas2017-07-17
| | | | | | | | | | | | | | | | | | One, logging for CREATE INDEX was oblivious to the fact that when an unlogged table is created, *only* operations on the init fork should be logged. Two, init fork buffers need to be flushed after they are written; otherwise, a filesystem-level copy following recovery may do the wrong thing. (There may be a better fix for this issue than the one used here, but this is transposed from the similar logic already present in XLogReadBufferForRedoExtended, and a broader refactoring after beta2 seems inadvisable.) Amit Kapila, reviewed by Ashutosh Sharma, Kyotaro Horiguchi, and Michael Paquier Discussion: http://postgr.es/m/CAA4eK1JpcMsEtOL_J7WODumeEfyrPi7FPYHeVdS7fyyrCrgp4w@mail.gmail.com
* Fix potential data corruption during freezeTeodor Sigaev2017-07-06
| | | | | | | Fix oversight in 3b97e6823b94 bug fix. Bitwise AND is used instead of OR and it cleans all bits in t_infomask heap tuple field. Backpatch to 9.3
* Fix typo in commentPeter Eisentraut2017-06-30
| | | | Author: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
* Fix typo in commentAlvaro Herrera2017-06-22
| | | | | | | | Once upon a time, WAL pointers could be NULL, but no longer. We talk about "valid" now. Reported-by: Amit Langote Discussion: https://postgr.es/m/33e9617d-27f1-eee8-3311-e27af98eaf2b@lab.ntt.co.jp
* Fix possibility of creating a "phantom" segment after promotion.Andres Freund2017-06-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When promoting a standby just after a XLOG_SWITCH record was replayed, and next segment(s) are already are locally available (via walsender, restore_command + trigger/recovery target), that segment could accidentally be recycled onto the past of the new timeline. Later checkpointer would create a .ready file for it, assuming there was an error during creation, and it would get archived. That causes trouble if another standby is later brought up from a basebackup from before the timeline creation, because it would try to read the segment, because XLogFileReadAnyTLI just tries all possible timelines, which doesn't have valid contents. Thus replay would fail. The problem, if already occurred, can be fixed by removing the segment and/or having restore_command filter it out. The reason for the creation of such "phantom" segments was, that after an XLOG_SWITCH record the EndOfLog variable points to the beginning of the next segment, and RemoveXlogFile() used XLByteToPrevSeg(). Normally RemoveXlogFile() doing so is harmless, because the last segment will still exist preventing InstallXLogFileSegment() from causing harm, but just after promotion there's no previous segment on the new timeline. Fix that by using XLByteToSeg() instead of XLByteToPrevSeg(). Author: Andres Freund Reported-By: Greg Burek Discussion: https://postgr.es/m/20170619073026.zcwpe6mydsaz5ygd@alap3.anarazel.de Backpatch: 9.2-, bug older than all supported versions
* Phase 3 of pgindent updates.Tom Lane2017-06-21
| | | | | | | | | | | | | | | | | | | | | | | | | Don't move parenthesized lines to the left, even if that means they flow past the right margin. By default, BSD indent lines up statement continuation lines that are within parentheses so that they start just to the right of the preceding left parenthesis. However, traditionally, if that resulted in the continuation line extending to the right of the desired right margin, then indent would push it left just far enough to not overrun the margin, if it could do so without making the continuation line start to the left of the current statement indent. That makes for a weird mix of indentations unless one has been completely rigid about never violating the 80-column limit. This behavior has been pretty universally panned by Postgres developers. Hence, disable it with indent's new -lpl switch, so that parenthesized lines are always lined up with the preceding left paren. This patch is much less interesting than the first round of indent changes, but also bulkier, so I thought it best to separate the effects. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
* Phase 2 of pgindent updates.Tom Lane2017-06-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change pg_bsd_indent to follow upstream rules for placement of comments to the right of code, and remove pgindent hack that caused comments following #endif to not obey the general rule. Commit e3860ffa4dd0dad0dd9eea4be9cc1412373a8c89 wasn't actually using the published version of pg_bsd_indent, but a hacked-up version that tried to minimize the amount of movement of comments to the right of code. The situation of interest is where such a comment has to be moved to the right of its default placement at column 33 because there's code there. BSD indent has always moved right in units of tab stops in such cases --- but in the previous incarnation, indent was working in 8-space tab stops, while now it knows we use 4-space tabs. So the net result is that in about half the cases, such comments are placed one tab stop left of before. This is better all around: it leaves more room on the line for comment text, and it means that in such cases the comment uniformly starts at the next 4-space tab stop after the code, rather than sometimes one and sometimes two tabs after. Also, ensure that comments following #endif are indented the same as comments following other preprocessor commands such as #else. That inconsistency turns out to have been self-inflicted damage from a poorly-thought-through post-indent "fixup" in pgindent. This patch is much less interesting than the first round of indent changes, but also bulkier, so I thought it best to separate the effects. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
* Initial pgindent run with pg_bsd_indent version 2.0.Tom Lane2017-06-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The new indent version includes numerous fixes thanks to Piotr Stefaniak. The main changes visible in this commit are: * Nicer formatting of function-pointer declarations. * No longer unexpectedly removes spaces in expressions using casts, sizeof, or offsetof. * No longer wants to add a space in "struct structname *varname", as well as some similar cases for const- or volatile-qualified pointers. * Declarations using PG_USED_FOR_ASSERTS_ONLY are formatted more nicely. * Fixes bug where comments following declarations were sometimes placed with no space separating them from the code. * Fixes some odd decisions for comments following case labels. * Fixes some cases where comments following code were indented to less than the expected column 33. On the less good side, it now tends to put more whitespace around typedef names that are not listed in typedefs.list. This might encourage us to put more effort into typedef name collection; it's not really a bug in indent itself. There are more changes coming after this round, having to do with comment indentation and alignment of lines appearing within parentheses. I wanted to limit the size of the diffs to something that could be reviewed without one's eyes completely glazing over, so it seemed better to split up the changes as much as practical. Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
* Fix typos in commentsMagnus Hagander2017-06-17
| | | | Author: Daniel Gustafsson <daniel@yesql.se>
* Avoid bogus TwoPhaseState locking sequencesAlvaro Herrera2017-06-14
| | | | | | | | | | | | | The optimized code in 728bd991c3c4 contains a few invalid locking sequences. To wit, the original code would try to acquire an lwlock that it already holds. Avoid this by moving lock acquisitions to higher-level code, and install appropriate assertions in low-level that the correct mode is held. Authors: Michael Paquier, Álvaro Herrera Reported-By: chuanting wang Bug: #14680 Discussion: https://postgr.es/m/20170531033228.1487.10124@wrigleys.postgresql.org
* Re-run pgindent.Tom Lane2017-06-13
| | | | | | | | This is just to have a clean base state for testing of Piotr Stefaniak's latest version of FreeBSD indent. I fixed up a couple of places where pgindent would have changed format not-nicely. perltidy not included. Discussion: https://postgr.es/m/VI1PR03MB119959F4B65F000CA7CD9F6BF2CC0@VI1PR03MB1199.eurprd03.prod.outlook.com
* Formatting improvements in config file samplesPeter Eisentraut2017-06-09
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* Update code commentsPeter Eisentraut2017-06-09
| | | | Author: Neha Khatri <nehakhatri5@gmail.com>
* Clean up latch related code.Andres Freund2017-06-06
| | | | | | | | | | | | | | | | | | | | | | The larger part of this patch replaces usages of MyProc->procLatch with MyLatch. The latter works even early during backend startup, where MyProc->procLatch doesn't yet. While the affected code shouldn't run in cases where it's not initialized, it might get copied into places where it might. Using MyLatch is simpler and a bit faster to boot, so there's little point to stick with the previous coding. While doing so I noticed some weaknesses around newly introduced uses of latches that could lead to missed events, and an omitted CHECK_FOR_INTERRUPTS() call in worker_spi. As all the actual bugs are in v10 code, there doesn't seem to be sufficient reason to backpatch this. Author: Andres Freund Discussion: https://postgr.es/m/20170606195321.sjmenrfgl2nu6j63@alap3.anarazel.de https://postgr.es/m/20170606210405.sim3yl6vpudhmufo@alap3.anarazel.de Backpatch: -
* Prevent possibility of panics during shutdown checkpoint.Andres Freund2017-06-05
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the checkpointer writes the shutdown checkpoint, it checks afterwards whether any WAL has been written since it started and throws a PANIC if so. At that point, only walsenders are still active, so one might think this could not happen, but walsenders can also generate WAL, for instance in BASE_BACKUP and logical decoding related commands (e.g. via hint bits). So they can trigger this panic if such a command is run while the shutdown checkpoint is being written. To fix this, divide the walsender shutdown into two phases. First, checkpointer, itself triggered by postmaster, sends a PROCSIG_WALSND_INIT_STOPPING signal to all walsenders. If the backend is idle or runs an SQL query this causes the backend to shutdown, if logical replication is in progress all existing WAL records are processed followed by a shutdown. Otherwise this causes the walsender to switch to the "stopping" state. In this state, the walsender will reject any further replication commands. The checkpointer begins the shutdown checkpoint once all walsenders are confirmed as stopping. When the shutdown checkpoint finishes, the postmaster sends us SIGUSR2. This instructs walsender to send any outstanding WAL, including the shutdown checkpoint record, wait for it to be replicated to the standby, and then exit. Author: Andres Freund, based on an earlier patch by Michael Paquier Reported-By: Fujii Masao, Andres Freund Reviewed-By: Michael Paquier Discussion: https://postgr.es/m/20170602002912.tqlwn4gymzlxpvs2@alap3.anarazel.de Backpatch: 9.4, where logical decoding was introduced
* Revert "Prevent panic during shutdown checkpoint"Andres Freund2017-06-05
| | | | | | | | | | | This reverts commit 086221cf6b1727c2baed4703c582f657b7c5350e, which was made to master only. The approach implemented in the above commit has some issues. While those could easily be fixed incrementally, doing so would make backpatching considerably harder, so instead first revert this patch. Discussion: https://postgr.es/m/20170602002912.tqlwn4gymzlxpvs2@alap3.anarazel.de
* Don't be so trusting that shm_toc_lookup() will always succeed.Tom Lane2017-06-05
| | | | | | | | | | | | | | | | | | Given the possibility of race conditions and so on, it seems entirely unsafe to just assume that shm_toc_lookup() always finds the key it's looking for --- but that was exactly what all but one call site were doing. To fix, add a "bool noError" argument, similarly to what we have in many other functions, and throw an error on an unexpected lookup failure. Remove now-redundant Asserts that a rather random subset of call sites had. I doubt this will throw any light on buildfarm member lorikeet's recent failures, because if an unnoticed lookup failure were involved, you'd kind of expect a null-pointer-dereference crash rather than the observed symptom. But you never know ... and this is better coding practice even if it never catches anything. Discussion: https://postgr.es/m/9697.1496675981@sss.pgh.pa.us
* Assorted translatable string fixesAlvaro Herrera2017-06-04
| | | | | Mark our rusage reportage string translatable; remove quotes from type names; unify formatting of very similar messages.
* Restore accidentally-removed line.Robert Haas2017-05-31
| | | | | | | | Commit 88e66d193fbaf756b3cc9bf94cad116aacbb355b is to blame. Masahiko Sawada Discussion: http://postgr.es/m/CAD21AoAXeb7O4hgg+efs8JT_SxpR4doAH5c5s-Z5WoRLstBZJA@mail.gmail.com
* brin: Don't crash on auto-summarizationAlvaro Herrera2017-05-30
| | | | | | | | | | | | | | We were trying to free a pointer into a shared buffer, which never works; and we were failing to release the buffer lock appropriately. Fix those omissions. While at it, improve documentation for brinGetTupleForHeapBlock, the inadequacy of which evidently caused these bugs in the first place. Reported independently by Zhou Digoal (bug #14668) and Alexander Sosna. Discussion: https://postgr.es/m/8c31c11b-6adb-228d-22c2-4ace89fc9209@credativ.de Discussion: https://postgr.es/m/20170524063323.29941.46339@wrigleys.postgresql.org
* Fix wording in amvalidate error messagesAlvaro Herrera2017-05-30
| | | | | | | | Remove some gratuituous message differences by making the AM name previously embedded in each message be a %s instead. While at it, get rid of terminology that's unclear and unnecessary in one message. Discussion: https://postgr.es/m/20170523001557.bq2hbq7hxyvyw62q@alvherre.pgsql
* Fix typo in commentMagnus Hagander2017-05-22
| | | | Author: Masahiko Sawada
* Post-PG 10 beta1 pgindent runBruce Momjian2017-05-17
| | | | perltidy run not included.
* Standardize "WAL location" terminologyPeter Eisentraut2017-05-12
| | | | Other previously used terms were "WAL position" or "log position".
* Replace "transaction log" with "write-ahead log"Peter Eisentraut2017-05-12
| | | | | This makes documentation and error messages match the renaming of "xlog" to "wal" in APIs and file naming.
* Rename WAL-related functions and views to use "lsn" not "location".Tom Lane2017-05-11
| | | | | | | | | | | | | | | Per discussion, "location" is a rather vague term that could refer to multiple concepts. "LSN" is an unambiguous term for WAL locations and should be preferred. Some function names, view column names, and function output argument names used "lsn" already, but others used "location", as well as yet other terms such as "wal_position". Since we've already renamed a lot of things in this area from "xlog" to "wal" for v10, we may as well incur a bit more compatibility pain and make these names all consistent. David Rowley, minor additional docs hacking by me Discussion: https://postgr.es/m/CAKJS1f8O0njDKe8ePFQ-LK5-EjwThsDws6ohJ-+c6nWK+oUxtg@mail.gmail.com
* Revert "Permit dump/reload of not-too-large >1GB tuples"Alvaro Herrera2017-05-10
| | | | | | | | | | | | | | | | | | | This reverts commits fa2fa9955280 and 42f50cb8fa98. While the functionality that was intended to be provided by these commits is desired, the patch didn't actually solve as many of the problematic situations as we hoped, and it created a bunch of its own problems. Since we're going to require more extensive changes soon for other reasons and users have been working around these problems for a long time already, there is no point in spending effort in fixing this halfway measure. Per complaint from Tom Lane. Discussion: https://postgr.es/m/21407.1484606922@sss.pgh.pa.us (Commit fa2fa9955280 had already been reverted in branches 9.5 as f858524ee4f and 9.6 as e9e44a0953, so this touches master only. Commit 42f50cb8fa98 was not present in the older branches.)
* Remove no-longer-needed compatibility code for hash indexes.Robert Haas2017-05-09
| | | | | | | | | | Because commit ea69a0dead5128c421140dc53fac165ba4af8520 bumped the HASH_VERSION, we don't need to worry about PostgreSQL 10 seeing bucket pages from earlier versions. Amit Kapila Discussion: http://postgr.es/m/CAA4eK1LAo4DGwh+mi-G3U8Pj1WkBBeFL38xdCnUHJv1z4bZFkQ@mail.gmail.com