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2017-04-07Reduce the number of pallocs() in BRINAlvaro Herrera
Instead of allocating memory in brin_deform_tuple and brin_copy_tuple over and over during a scan, allow reuse of previously allocated memory. This is said to make for a measurable performance improvement. Author: Jinyu Zhang, Álvaro Herrera Reviewed by: Tomas Vondra Discussion: https://postgr.es/m/495deb78.4186.1500dacaa63.Coremail.beijing_pg@163.com
2017-04-07Fix new BRIN desummarize WAL recordAlvaro Herrera
The WAL-writing piece was forgetting to set the pages-per-range value. Also, fix the declared type of struct member heapBlk, which I mistakenly set as OffsetNumber rather than BlockNumber. Problem was introduced by commit c655899ba9ae (April 1st). Any system that tries to replay the new WAL record written before this fix is likely to die on replay and require pg_resetwal. Reported by Tom Lane. Discussion: https://postgr.es/m/20191.1491524824@sss.pgh.pa.us
2017-04-06Clean up after insufficiently-researched optimization of tuple conversions.Tom Lane
tupconvert.c's functions formerly considered that an explicit tuple conversion was necessary if the input and output tupdescs contained different type OIDs. The point of that was to make sure that a composite datum resulting from the conversion would contain the destination rowtype OID in its composite-datum header. However, commit 3838074f8 entirely misunderstood what that check was for, thinking that it had something to do with presence or absence of an OID column within the tuple. Removal of the check broke the no-op conversion path in ExecEvalConvertRowtype, as reported by Ashutosh Bapat. It turns out that of the dozen or so call sites for tupconvert.c functions, ExecEvalConvertRowtype is the only one that cares about the composite-datum header fields in the output tuple. In all the rest, we'd much rather avoid an unnecessary conversion whenever the tuples are physically compatible. Moreover, the comments in tupconvert.c only promise physical compatibility not a metadata match. So, let's accept the removal of the guarantee about the output tuple's rowtype marking, recognizing that this is a API change that could conceivably break third-party callers of tupconvert.c. (So, let's remember to mention it in the v10 release notes.) However, commit 3838074f8 did have a bit of a point here, in that two tuples mustn't be considered physically compatible if one has HEAP_HASOID set and the other doesn't. (Some of the callers of tupconvert.c might not really care about that, but we can't assume it in general.) The previous check accidentally covered that issue, because no RECORD types ever have OIDs, while if two tupdescs have the same named composite type OID then, a fortiori, they have the same tdhasoid setting. If we're removing the type OID match check then we'd better include tdhasoid match as part of the physical compatibility check. Without that hack in tupconvert.c, we need ExecEvalConvertRowtype to take responsibility for inserting the correct rowtype OID label whenever tupconvert.c decides it need not do anything. This is easily done with heap_copy_tuple_as_datum, which will be considerably faster than a tuple disassembly and reassembly anyway; so from a performance standpoint this change is a win all around compared to what happened in earlier branches. It just means a couple more lines of code in ExecEvalConvertRowtype. Ashutosh Bapat and Tom Lane Discussion: https://postgr.es/m/CAFjFpRfvHABV6+oVvGcshF8rHn+1LfRUhj7Jz1CDZ4gPUwehBg@mail.gmail.com
2017-04-06Fix BRIN cost estimationAlvaro Herrera
The original code was overly optimistic about the cost of scanning a BRIN index, leading to BRIN indexes being selected when they'd be a worse choice than some other index. This complete rewrite should be more accurate. Author: David Rowley, based on an earlier patch by Emre Hasegeli Reviewed-by: Emre Hasegeli Discussion: https://postgr.es/m/CAKJS1f9n-Wapop5Xz1dtGdpdqmzeGqQK4sV2MK-zZugfC14Xtw@mail.gmail.com
2017-04-06Fix mixup of bool and ternary valuePeter Eisentraut
Not currently a problem, but could be with stricter bool behavior under stdbool or C++. Reviewed-by: Andres Freund <andres@anarazel.de>
2017-04-06Always SnapshotResetXmin() during ClearTransaction()Simon Riggs
Avoid corner cases during 2PC with 6bad580d9e678a0b604883e14d8401d469b06566
2017-04-06Identity columnsPeter Eisentraut
This is the SQL standard-conforming variant of PostgreSQL's serial columns. It fixes a few usability issues that serial columns have: - CREATE TABLE / LIKE copies default but refers to same sequence - cannot add/drop serialness with ALTER TABLE - dropping default does not drop sequence - need to grant separate privileges to sequence - other slight weirdnesses because serial is some kind of special macro Reviewed-by: Vitaly Burovoy <vitaly.burovoy@gmail.com>
2017-04-06Avoid SnapshotResetXmin() during AtEOXact_Snapshot()Simon Riggs
For normal commits and aborts we already reset PgXact->xmin, so we can simply avoid running SnapshotResetXmin() twice. During performance tests by Alexander Korotkov, diagnosis by Andres Freund showed PgXact array as a bottleneck. After manual analysis by me of the code paths that touch those memory locations, I was able to identify extraneous code in the main transaction commit path. Avoiding touching highly contented shmem improves concurrent performance slightly on all workloads, confirmed by tests run by Ashutosh Sharma and Alexander Korotkov. Simon Riggs Discussion: CANP8+jJdXE9b+b9F8CQT-LuxxO0PBCB-SZFfMVAdp+akqo4zfg@mail.gmail.com
2017-04-05Fix pageinspect failures on hash indexes.Robert Haas
Make every page in a hash index which isn't all-zeroes have a valid special space, so that tools like pageinspect don't error out. Also, make pageinspect cope with all-zeroes pages, because _hash_alloc_buckets can leave behind large numbers of those until they're consumed by splits. Ashutosh Sharma and Robert Haas, reviewed by Amit Kapila. Original trouble report from Jeff Janes. Discussion: http://postgr.es/m/CAMkU=1y6NjKmqbJ8wLMhr=F74WzcMALYWcVFhEpm7i=mV=XsOg@mail.gmail.com
2017-04-05hash: Fix write-ahead logging bug.Robert Haas
The size of the data is not the same thing as the size of the size of the data. Reported off-list by Tushar Ahuja. Fix by Ashutosh Sharma, reviewed by Amit Kapila. Discussion: http://postgr.es/m/CAE9k0PnmPDXfvf8HDObme7q_Ewc4E26ukHXUBPySoOs0ObqqaQ@mail.gmail.com
2017-04-05Capitalize names of PLs consistentlyPeter Eisentraut
Author: Daniel Gustafsson <daniel@yesql.se>
2017-04-04Make min_wal_size/max_wal_size use MB internallySimon Riggs
Previously they were defined using multiples of XLogSegSize. Remove GUC_UNIT_XSEGS. Introduce GUC_UNIT_MB Extracted from patch series on XLogSegSize infrastructure. Beena Emerson
2017-04-04Fix uninitialized variables in twophase.cSimon Riggs
2017-04-04Speedup 2PC recovery by skipping two phase state files in normal pathSimon Riggs
2PC state info held in shmem at PREPARE, then cleaned at COMMIT PREPARED/ABORT PREPARED, avoiding writing/fsyncing any state information to disk in the normal path, greatly enhancing replay speed. Prepared transactions that live past one checkpoint redo horizon will be written to disk as now. Similar conceptually to 978b2f65aa1262eb4ecbf8b3785cb1b9cf4db78e and building upon the infrastructure created by that commit. Authors, in equal measure: Stas Kelvich, Nikhil Sontakke and Michael Paquier Discussion: https://postgr.es/m/CAMGcDxf8Bn9ZPBBJZba9wiyQq-Qk5uqq=VjoMnRnW5s+fKST3w@mail.gmail.com
2017-04-04Fix formula in _hash_spareindex.Robert Haas
This was correct in earlier versions of the patch that lead to commit ea69a0dead5128c421140dc53fac165ba4af8520, but somehow got broken in the last version which I actually committed. Mithun Cy, per an off-list report from Ashutosh Sharma Discussion: http://postgr.es/m/CAD__OujbAwNU71v1y-RoQxZ8LZ6-V2UFTkex3v34MK6uZ3Xb5w@mail.gmail.com
2017-04-03Expand hash indexes more gradually.Robert Haas
Since hash indexes typically have very few overflow pages, adding a new splitpoint essentially doubles the on-disk size of the index, which can lead to large and abrupt increases in disk usage (and perhaps long delays on occasion). To mitigate this problem to some degree, divide larger splitpoints into four equal phases. This means that, for example, instead of growing from 4GB to 8GB all at once, a hash index will now grow from 4GB to 5GB to 6GB to 7GB to 8GB, which is perhaps still not as smooth as we'd like but certainly an improvement. This changes the on-disk format of the metapage, so bump HASH_VERSION from 2 to 3. This will force a REINDEX of all existing hash indexes, but that's probably a good idea anyway. First, hash indexes from pre-10 versions of PostgreSQL could easily be corrupted, and we don't want to confuse corruption carried over from an older release with any corruption caused despite the new write-ahead logging in v10. Second, it will let us remove some backward-compatibility code added by commit 293e24e507838733aba4748b514536af2d39d7f2. Mithun Cy, reviewed by Amit Kapila, Jesper Pedersen and me. Regression test outputs updated by me. Discussion: http://postgr.es/m/CAD__OuhG6F1gQLCgMQNnMNgoCvOLQZz9zKYJQNYvYmmJoM42gA@mail.gmail.com Discussion: http://postgr.es/m/CA+TgmoYty0jCf-pa+m+vYUJ716+AxM7nv_syvyanyf5O-L_i2A@mail.gmail.com
2017-04-03Properly acquire buffer lock for page-at-a-time hash vacuum.Robert Haas
In a couple of places, _hash_kill_items was mistakenly called with the buffer lock not held. Repair. Ashutosh Sharma, per a report from Andreas Seltenreich Discussion: http://postgr.es/m/87o9wo8o0j.fsf@credativ.de
2017-04-01BRIN de-summarizationAlvaro Herrera
When the BRIN summary tuple for a page range becomes too "wide" for the values actually stored in the table (because the tuples that were present originally are no longer present due to updates or deletes), it can be useful to remove the outdated summary tuple, so that a future summarization can install a tighter summary. This commit introduces a SQL-callable interface to do so. Author: Álvaro Herrera Reviewed-by: Eiji Seki Discussion: https://postgr.es/m/20170228045643.n2ri74ara4fhhfxf@alvherre.pgsql
2017-04-01BRIN auto-summarizationAlvaro Herrera
Previously, only VACUUM would cause a page range to get initially summarized by BRIN indexes, which for some use cases takes too much time since the inserts occur. To avoid the delay, have brininsert request a summarization run for the previous range as soon as the first tuple is inserted into the first page of the next range. Autovacuum is in charge of processing these requests, after doing all the regular vacuuming/ analyzing work on tables. This doesn't impose any new tasks on autovacuum, because autovacuum was already in charge of doing summarizations. The only actual effect is to change the timing, i.e. that it occurs earlier. For this reason, we don't go any great lengths to record these requests very robustly; if they are lost because of a server crash or restart, they will happen at a later time anyway. Most of the new code here is in autovacuum, which can now be told about "work items" to process. This can be used for other things such as GIN pending list cleaning, perhaps visibility map bit setting, both of which are currently invoked during vacuum, but do not really depend on vacuum taking place. The requests are at the page range level, a granularity for which we did not have SQL-level access; we only had index-level summarization requests via brin_summarize_new_values(). It seems reasonable to add SQL-level access to range-level summarization too, so add a function brin_summarize_range() to do that. Authors: Álvaro Herrera, based on sketch from Simon Riggs. Reviewed-by: Thomas Munro. Discussion: https://postgr.es/m/20170301045823.vneqdqkmsd4as4ds@alvherre.pgsql
2017-03-31Don't use bgw_main even to specify in-core bgworker entrypoints.Robert Haas
On EXEC_BACKEND builds, this can fail if ASLR is in use. Backpatch to 9.5. On master, completely remove the bgw_main field completely, since there is no situation in which it is safe for an EXEC_BACKEND build. On 9.6 and 9.5, leave the field intact to avoid breaking things for third-party code that doesn't care about working under EXEC_BACKEND. Prior to 9.5, there are no in-core bgworker entrypoints. Petr Jelinek, reviewed by me. Discussion: http://postgr.es/m/09d8ad33-4287-a09b-a77f-77f8761adb5e@2ndquadrant.com
2017-03-31Don't allocate storage for partitioned tables.Robert Haas
Also, don't allow setting reloptions on them, since that would have no effect given the lack of storage. The patch does this by introducing a new reloption kind for which there are currently no reloptions -- we might have some in the future -- so it adjusts parseRelOptions to handle that case correctly. Bumped catversion. System catalogs that contained reloptions for partitioned tables are no longer valid; plus, there are now fewer physical files on disk, which is not technically a catalog change but still a good reason to re-initdb. Amit Langote, reviewed by Maksim Milyutin and Kyotaro Horiguchi and revised a bit by me. Discussion: http://postgr.es/m/20170331.173326.212311140.horiguchi.kyotaro@lab.ntt.co.jp
2017-03-29Simplify check of modified attributes in heap_updateAlvaro Herrera
The old coding was getting more complicated as new things were added, and it would be barely tolerable with upcoming WARM updates and other future features such as indirect indexes. The new coding incurs a small performance cost in synthetic benchmark cases, and is barely measurable in normal cases. A much larger benefit is expected from WARM, which could actually bolt its needs on top of the existing coding, but it is much uglier and bug-prone than doing it on this new code. Additional optimization can be applied on top of this, if need be. Reviewed-by: Pavan Deolasee, Amit Kapila, Mithun CY Discussion: https://postgr.es/m/20161228232018.4hc66ndrzpz4g4wn@alvherre.pgsql https://postgr.es/m/CABOikdMJfz69dBNRTOZcB6s5A0tf8OMCyQVYQyR-WFFdoEwKMQ@mail.gmail.com
2017-03-28Remove direct uses of ItemPointer.{ip_blkid,ip_posid}Alvaro Herrera
There are no functional changes here; this simply encapsulates knowledge of the ItemPointerData struct so that a future patch can change things without more breakage. All direct users of ip_blkid and ip_posid are changed to use existing macros ItemPointerGetBlockNumber and ItemPointerGetOffsetNumber respectively. For callers where that's inappropriate (because they Assert that the itempointer is is valid-looking), add ItemPointerGetBlockNumberNoCheck and ItemPointerGetOffsetNumberNoCheck, which lack the assertion but are otherwise identical. Author: Pavan Deolasee Discussion: https://postgr.es/m/CABOikdNnFon4cJiL=h1mZH3bgUeU+sWHuU4Yr8AB=j3A2p1GiA@mail.gmail.com
2017-03-28Correct grammar in error messageSimon Riggs
"could not generate" rather than "could not generation" from commit 818fd4a67d610991757b610755e3065fb99d80a5
2017-03-28Suppress implicit-conversion warnings seen with newer clang versions.Tom Lane
We were assigning values near 255 through "char *" pointers. On machines where char is signed, that's not entirely kosher, and it's reasonable for compilers to warn about it. A better solution would be to change the pointer type to "unsigned char *", but that would be vastly more invasive. For the moment, let's just apply this simple backpatchable solution. Aleksander Alekseev Discussion: https://postgr.es/m/20170220141239.GD12278@e733.localdomain Discussion: https://postgr.es/m/2839.1490714708@sss.pgh.pa.us
2017-03-27Still more code review for single-page hash vacuuming.Robert Haas
Most seriously, fix use of incorrect block ID, per a report from Jeff Janes that it causes a crash and a diagnosis from Amit Kapila. Improve consistency between the hash and btree versions of this code by adding back a PANIC that btree has, and by registering data in the xlog record in the same way, per complaints from Jeff Janes and Amit Kapila. Tidy up some minor cosmetic points, per complaints from Amit Kapila. Patch by Ashutosh Sharma, reviewed by Amit Kapila, and tested by Jeff Janes. Discussion: http://postgr.es/m/CAMkU=1w-9Qe=Ff1o6bSaXpNO9wqpo7_9GL8_CVhw4BoVVHasqg@mail.gmail.com
2017-03-27Fsync directory after creating or unlinking file.Teodor Sigaev
If file was created/deleted just before powerloss it's possible that file system will miss that. To prevent it, call fsync() where creating/ unlinkg file is critical. Author: Michael Paquier Reviewed-by: Ashutosh Bapat, Takayuki Tsunakawa, me
2017-03-26Fix comment.Robert Haas
Cut-and-paste led to something silly. Ashutosh Sharma, reviewed by Amit Kapila and by me Discussion: http://postgr.es/m/CAE9k0PmUbvQSBY7kwN_OkuqBYyHRXBX-c1ZkuAgR5vgF0GeWzQ@mail.gmail.com
2017-03-26Improve performance of ExecEvalWholeRowVar.Tom Lane
In commit b8d7f053c, we needed to fix ExecEvalWholeRowVar to not change the state of the slot it's copying. The initial quick hack at that required two rounds of tuple construction, which is not very nice. To fix, add another primitive to tuptoaster.c that does precisely what we need. (I initially tried to do this by refactoring one of the existing functions into two pieces; but it looked like that might hurt performance for the existing case, and the amount of code that could be shared is not very large, so I gave up on that.) Discussion: https://postgr.es/m/26088.1490315792@sss.pgh.pa.us
2017-03-24Reverting 42b4b0b2413b9b472aaf2112a3bbfd80a6ab4dc5Simon Riggs
Buildfarm issues and other reported issues
2017-03-24Avoid SnapshotResetXmin() during AtEOXact_Snapshot()Simon Riggs
For normal commits and aborts we already reset PgXact->xmin Avoiding touching highly contented shmem improves concurrent performance. Simon Riggs Discussion: CANP8+jJdXE9b+b9F8CQT-LuxxO0PBCB-SZFfMVAdp+akqo4zfg@mail.gmail.com
2017-03-24Fix backup cancelingTeodor Sigaev
Assert-enabled build crashes but without asserts it works by wrong way: it may not reset forcing full page write and preventing from starting exclusive backup with the same name as cancelled. Patch replaces pair of booleans nonexclusive_backup_running/exclusive_backup_running to single enum to correctly describe backup state. Backpatch to 9.6 where bug was introduced Reported-by: David Steele Authors: Michael Paquier, David Steele Reviewed-by: Anastasia Lubennikova https://commitfest.postgresql.org/13/1068/
2017-03-23Track the oldest XID that can be safely looked up in CLOG.Robert Haas
This provides infrastructure for looking up arbitrary, user-supplied XIDs without a risk of scary-looking failures from within the clog module. Normally, the oldest XID that can be safely looked up in CLOG is the same as the oldest XID that can reused without causing wraparound, and the latter is already tracked. However, while truncation is in progress, the values are different, so we must keep track of them separately. Craig Ringer, reviewed by Simon Riggs and by me. Discussion: http://postgr.es/m/CAMsr+YHQiWNEi0daCTboS40T+V5s_+dst3PYv_8v2wNVH+Xx4g@mail.gmail.com
2017-03-23Reduce page locking in GIN vacuumTeodor Sigaev
GIN vacuum during cleaning posting tree can lock this whole tree for a long time with by holding LockBufferForCleanup() on root. Patch changes it with two ways: first, cleanup lock will be taken only if there is an empty page (which should be deleted) and, second, it tries to lock only subtree, not the whole posting tree. Author: Andrey Borodin with minor editorization by me Reviewed-by: Jeff Davis, me https://commitfest.postgresql.org/13/896/
2017-03-23Replication lag tracking for walsendersSimon Riggs
Adds write_lag, flush_lag and replay_lag cols to pg_stat_replication. Implements a lag tracker module that reports the lag times based upon measurements of the time taken for recent WAL to be written, flushed and replayed and for the sender to hear about it. These times represent the commit lag that was (or would have been) introduced by each synchronous commit level, if the remote server was configured as a synchronous standby. For an asynchronous standby, the replay_lag column approximates the delay before recent transactions became visible to queries. If the standby server has entirely caught up with the sending server and there is no more WAL activity, the most recently measured lag times will continue to be displayed for a short time and then show NULL. Physical replication lag tracking is automatic. Logical replication tracking is possible but is the responsibility of the logical decoding plugin. Tracking is a private module operating within each walsender individually, with values reported to shared memory. Module not used outside of walsender. Design and code is good enough now to commit - kudos to the author. In many ways a difficult topic, with important and subtle behaviour so this shoudl be expected to generate discussion and multiple open items: Test now! Author: Thomas Munro, following designs by Fujii Masao and Simon Riggs Review: Simon Riggs, Ian Barwick and Craig Ringer
2017-03-22Expose waitforarchive option through pg_stop_backup()Stephen Frost
Internally, we have supported the option to either wait for all of the WAL associated with a backup to be archived, or to return immediately. This option is useful to users of pg_stop_backup() as well, when they are reading the stop backup record position and checking that the WAL they need has been archived independently. This patch adds an additional, optional, argument to pg_stop_backup() which allows the user to indicate if they wish to wait for the WAL to be archived or not. The default matches current behavior, which is to wait. Author: David Steele, with some minor changes, doc updates by me. Reviewed by: Takayuki Tsunakawa, Fujii Masao Discussion: https://postgr.es/m/758e3fd1-45b4-5e28-75cd-e9e7f93a4c02@pgmasters.net
2017-03-22Refactor GetOldestXmin() to use flagsSimon Riggs
Replace ignoreVacuum parameter with more flexible flags. Author: Eiji Seki Review: Haribabu Kommi
2017-03-22Improve performance of replay of AccessExclusiveLocksSimon Riggs
A hot standby replica keeps a list of Access Exclusive locks for a top level transaction. These locks are released when the top level transaction ends. Searching of this list is O(N^2), and each transaction had to pay the price of searching this list for locks, even if it didn't take any AE locks itself. This patch optimizes this case by having the master server track which transactions took AE locks, and passes that along to the standby server in the commit/abort record. This allows the standby to only try to release locks for transactions which actually took any, avoiding the majority of the performance issue. Refactor MyXactAccessedTempRel into MyXactFlags to allow minimal additional cruft with this. Analysis and initial patch by David Rowley Author: David Rowley and Simon Riggs
2017-03-22Teach xlogreader to follow timeline switchesSimon Riggs
Uses page-based mechanism to ensure we’re using the correct timeline. Tests are included to exercise the functionality using a cold disk-level copy of the master that's started up as a replica with slots intact, but the intended use of the functionality is with later features. Craig Ringer, reviewed by Simon Riggs and Andres Freund
2017-03-20Another fix for single-page hash index vacuum.Robert Haas
The WAL consistency checking code needed to be updated for the new page status bit, but that didn't get done previously. Ashutosh Sharma, reviewed by Amit Kapila Discussion: http://postgr.es/m/CAA4eK1LP_oz4EfMen14OjJuzN5CqPdfRkFFuA-MfkcfeE8zGyg@mail.gmail.com
2017-03-20Fixes for single-page hash index vacuum.Robert Haas
Clear LH_PAGE_HAS_DEAD_TUPLES during replay, similar to what gets done for btree. Update hashdesc.c for xl_hash_vacuum_one_page. Oversights in commit 6977b8b7f4dfb40896ff5e2175cad7fdbda862eb spotted by Amit Kapila. Patch by Ashutosh Sharma. Bump WAL version. The original patch to make hash indexes write-ahead logged probably should have done this, and the single page vacuuming patch probably should have done it again, but better late than never. Discussion: http://postgr.es/m/CAA4eK1Kd=mJ9xreovcsh0qMiAj-QqCphHVQ_Lfau1DR9oVjASQ@mail.gmail.com
2017-03-18Create and use wait events for read, write, and fsync operations.Robert Haas
Previous commits, notably 53be0b1add7064ca5db3cd884302dfc3268d884e and 6f3bd98ebfc008cbd676da777bb0b2376c4c4bfa, made it possible to see from pg_stat_activity when a backend was stuck waiting for another backend, but it's also fairly common for a backend to be stuck waiting for an I/O. Add wait events for those operations, too. Rushabh Lathia, with further hacking by me. Reviewed and tested by Michael Paquier, Amit Kapila, Rajkumar Raghuwanshi, and Rahila Syed. Discussion: http://postgr.es/m/CAGPqQf0LsYHXREPAZqYGVkDqHSyjf=KsD=k0GTVPAuzyThh-VQ@mail.gmail.com
2017-03-17Rename "pg_clog" directory to "pg_xact".Robert Haas
Names containing the letters "log" sometimes confuse users into believing that only non-critical data is present. It is hoped this renaming will discourage ill-considered removals of transaction status data. Michael Paquier Discussion: http://postgr.es/m/CA+Tgmoa9xFQyjRZupbdEFuwUerFTvC6HjZq1ud6GYragGDFFgA@mail.gmail.com
2017-03-15Port single-page btree vacuum logic to hash indexes.Robert Haas
This is advantageous for hash indexes for the same reasons it's good for btrees: it accelerates space recycling, reducing bloat. Ashutosh Sharma, reviewed by Amit Kapila and by me. A bit of additional hacking by me. Discussion: http://postgr.es/m/CAE9k0PkRSyzx8dOnokEpUi2A-RFZK72WN0h9DEMv_ut9q6bPRw@mail.gmail.com
2017-03-15Cosmetic fixes for hash index write-ahead logging.Robert Haas
Amit Kapila. One of these was reported by Tom Lane. Discussion: http://postgr.es/m/5515.1489514099@sss.pgh.pa.us
2017-03-14hash: Support WAL consistency checking.Robert Haas
Kuntal Ghosh, reviewed by Amit Kapila and Ashutosh Sharma, with a few tweaks by me. Discussion: http://postgr.es/m/CAGz5QCJLERUn_zoO0eDv6_Y_d0o4tNTMPeR7ivTLBg4rUrJdwg@mail.gmail.com
2017-03-14hash: Add write-ahead logging support.Robert Haas
The warning about hash indexes not being write-ahead logged and their use being discouraged has been removed. "snapshot too old" is now supported for tables with hash indexes. Most importantly, barring bugs, hash indexes will now be crash-safe and usable on standbys. This commit doesn't yet add WAL consistency checking for hash indexes, as we now have for other index types; a separate patch has been submitted to cure that lack. Amit Kapila, reviewed and slightly modified 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. Discussion: http://postgr.es/m/CAA4eK1JOBX=YU33631Qh-XivYXtPSALh514+jR8XeD7v+K3r_Q@mail.gmail.com
2017-03-14Spelling fixesPeter Eisentraut
From: Josh Soref <jsoref@gmail.com>
2017-03-14Spelling fixes in code commentsPeter Eisentraut
From: Josh Soref <jsoref@gmail.com>
2017-03-14Make logging about multixact wraparound protection less chatty.Tom Lane
The original messaging design, introduced in commit 068cfadf9, seems too chatty now that some time has elapsed since the bug fix; most installations will be in good shape and don't really need a reminder about this on every postmaster start. Hence, arrange to suppress the "wraparound protections are now enabled" message during startup (specifically, during the TrimMultiXact() call). The message will still appear if protection becomes effective at some later point. Discussion: https://postgr.es/m/17211.1489189214@sss.pgh.pa.us