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[PATCH 2/5] Remove TLI from some argument lists. 15+ messages / 3 participants [nested] [flat]
* [PATCH 2/5] Remove TLI from some argument lists. @ 2019-07-09 09:54 Antonin Houska <ah@cybertec.at> 0 siblings, 0 replies; 15+ messages in thread From: Antonin Houska @ 2019-07-09 09:54 UTC (permalink / raw) The timeline information is available to caller via XLogReaderState. Now that XLogRead() is gonna be (sometimes) responsible for determining the TLI, it would have to be added the (TimeLineID *) argument too, just to be consistent with the current coding style. Since XLogRead() updates also other position-specific fields of XLogReaderState, it seems simpler if we remove the output argument from XLogPageReadCB and always report the TLI via XLogReaderState. --- src/backend/access/transam/xlog.c | 7 +++---- src/backend/access/transam/xlogreader.c | 6 +++--- src/backend/access/transam/xlogutils.c | 11 ++++++----- src/backend/replication/logical/logicalfuncs.c | 4 ++-- src/backend/replication/walsender.c | 2 +- src/bin/pg_rewind/parsexlog.c | 9 ++++----- src/bin/pg_waldump/pg_waldump.c | 2 +- src/include/access/xlogreader.h | 8 +++----- src/include/access/xlogutils.h | 5 ++--- src/include/replication/logicalfuncs.h | 2 +- 10 files changed, 26 insertions(+), 30 deletions(-) diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index b6c9353cbd..f30c2ce0ce 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -885,8 +885,7 @@ static int XLogFileRead(XLogSegNo segno, int emode, TimeLineID tli, int source, bool notfoundOk); static int XLogFileReadAnyTLI(XLogSegNo segno, int emode, int source); static int XLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *readBuf, - TimeLineID *readTLI); + int reqLen, XLogRecPtr targetRecPtr, char *readBuf); static bool WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess, bool fetching_ckpt, XLogRecPtr tliRecPtr); static int emode_for_corrupt_record(int emode, XLogRecPtr RecPtr); @@ -11520,7 +11519,7 @@ CancelBackup(void) */ static int XLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, int reqLen, - XLogRecPtr targetRecPtr, char *readBuf, TimeLineID *readTLI) + XLogRecPtr targetRecPtr, char *readBuf) { XLogPageReadPrivate *private = (XLogPageReadPrivate *) xlogreader->private_data; @@ -11637,7 +11636,7 @@ retry: Assert(targetPageOff == readOff); Assert(reqLen <= readLen); - *readTLI = curFileTLI; + xlogreader->readPageTLI = curFileTLI; /* * Check the page header immediately, so that we can retry immediately if diff --git a/src/backend/access/transam/xlogreader.c b/src/backend/access/transam/xlogreader.c index 08bc9695c1..ed7a72bc14 100644 --- a/src/backend/access/transam/xlogreader.c +++ b/src/backend/access/transam/xlogreader.c @@ -557,7 +557,7 @@ ReadPageInternal(XLogReaderState *state, XLogRecPtr pageptr, int reqLen) readLen = state->read_page(state, targetSegmentPtr, XLOG_BLCKSZ, state->currRecPtr, - state->readBuf, &state->readPageTLI); + state->readBuf); if (readLen < 0) goto err; @@ -575,7 +575,7 @@ ReadPageInternal(XLogReaderState *state, XLogRecPtr pageptr, int reqLen) */ readLen = state->read_page(state, pageptr, Max(reqLen, SizeOfXLogShortPHD), state->currRecPtr, - state->readBuf, &state->readPageTLI); + state->readBuf); if (readLen < 0) goto err; @@ -594,7 +594,7 @@ ReadPageInternal(XLogReaderState *state, XLogRecPtr pageptr, int reqLen) { readLen = state->read_page(state, pageptr, XLogPageHeaderSize(hdr), state->currRecPtr, - state->readBuf, &state->readPageTLI); + state->readBuf); if (readLen < 0) goto err; } diff --git a/src/backend/access/transam/xlogutils.c b/src/backend/access/transam/xlogutils.c index 10a663bae6..cba180912b 100644 --- a/src/backend/access/transam/xlogutils.c +++ b/src/backend/access/transam/xlogutils.c @@ -909,12 +909,12 @@ XLogReadDetermineTimeline(XLogReaderState *state, XLogRecPtr wantPage, uint32 wa */ int read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *cur_page, - TimeLineID *pageTLI) + int reqLen, XLogRecPtr targetRecPtr, char *cur_page) { XLogRecPtr read_upto, loc; int count; + TimeLineID pageTLI; loc = targetPagePtr + reqLen; @@ -934,7 +934,7 @@ read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, else read_upto = GetXLogReplayRecPtr(&ThisTimeLineID); - *pageTLI = ThisTimeLineID; + pageTLI = ThisTimeLineID; /* * Check which timeline to get the record from. @@ -991,7 +991,7 @@ read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, * nothing cares so long as the timeline doesn't go backwards. We * should read the page header instead; FIXME someday. */ - *pageTLI = state->currTLI; + pageTLI = state->currTLI; /* No need to wait on a historical timeline */ break; @@ -1022,8 +1022,9 @@ read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, * as 'count', read the whole page anyway. It's guaranteed to be * zero-padded up to the page boundary if it's incomplete. */ - XLogRead(cur_page, state->wal_segment_size, *pageTLI, targetPagePtr, + XLogRead(cur_page, state->wal_segment_size, pageTLI, targetPagePtr, XLOG_BLCKSZ); + state->readPageTLI = pageTLI; /* number of valid bytes in the buffer */ return count; diff --git a/src/backend/replication/logical/logicalfuncs.c b/src/backend/replication/logical/logicalfuncs.c index d974400d6e..d1cf80d441 100644 --- a/src/backend/replication/logical/logicalfuncs.c +++ b/src/backend/replication/logical/logicalfuncs.c @@ -116,10 +116,10 @@ check_permissions(void) int logical_read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *cur_page, TimeLineID *pageTLI) + int reqLen, XLogRecPtr targetRecPtr, char *cur_page) { return read_local_xlog_page(state, targetPagePtr, reqLen, - targetRecPtr, cur_page, pageTLI); + targetRecPtr, cur_page); } /* diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c index e7a59b0a92..c8802bbc1f 100644 --- a/src/backend/replication/walsender.c +++ b/src/backend/replication/walsender.c @@ -763,7 +763,7 @@ StartReplication(StartReplicationCmd *cmd) */ static int logical_read_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, - XLogRecPtr targetRecPtr, char *cur_page, TimeLineID *pageTLI) + XLogRecPtr targetRecPtr, char *cur_page) { XLogRecPtr flushptr; int count; diff --git a/src/bin/pg_rewind/parsexlog.c b/src/bin/pg_rewind/parsexlog.c index 287af60c4e..00168c27dc 100644 --- a/src/bin/pg_rewind/parsexlog.c +++ b/src/bin/pg_rewind/parsexlog.c @@ -47,10 +47,10 @@ typedef struct XLogPageReadPrivate int tliIndex; } XLogPageReadPrivate; + static int SimpleXLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *readBuf, - TimeLineID *pageTLI); + int reqLen, XLogRecPtr targetRecPtr, char *readBuf); /* * Read WAL from the datadir/pg_wal, starting from 'startpoint' on timeline @@ -238,8 +238,7 @@ findLastCheckpoint(const char *datadir, XLogRecPtr forkptr, int tliIndex, /* XLogreader callback function, to read a WAL page */ static int SimpleXLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *readBuf, - TimeLineID *pageTLI) + int reqLen, XLogRecPtr targetRecPtr, char *readBuf) { XLogPageReadPrivate *private = (XLogPageReadPrivate *) xlogreader->private_data; uint32 targetPageOff; @@ -322,7 +321,7 @@ SimpleXLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, Assert(targetSegNo == xlogreadsegno); - *pageTLI = targetHistory[private->tliIndex].tli; + xlogreader->readPageTLI = targetHistory[private->tliIndex].tli; return XLOG_BLCKSZ; } diff --git a/src/bin/pg_waldump/pg_waldump.c b/src/bin/pg_waldump/pg_waldump.c index b95d467805..40c64a0bbf 100644 --- a/src/bin/pg_waldump/pg_waldump.c +++ b/src/bin/pg_waldump/pg_waldump.c @@ -423,7 +423,7 @@ XLogDumpXLogRead(const char *directory, TimeLineID timeline_id, */ static int XLogDumpReadPage(XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, - XLogRecPtr targetPtr, char *readBuff, TimeLineID *curFileTLI) + XLogRecPtr targetPtr, char *readBuff) { XLogDumpPrivate *private = state->private_data; int count = XLOG_BLCKSZ; diff --git a/src/include/access/xlogreader.h b/src/include/access/xlogreader.h index a3d3cc1e7b..e23223ba5b 100644 --- a/src/include/access/xlogreader.h +++ b/src/include/access/xlogreader.h @@ -34,8 +34,7 @@ typedef int (*XLogPageReadCB) (XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, int reqLen, XLogRecPtr targetRecPtr, - char *readBuf, - TimeLineID *pageTLI); + char *readBuf); typedef struct { @@ -95,9 +94,8 @@ struct XLogReaderState * actual WAL record it's interested in. In that case, targetRecPtr can * be used to determine which timeline to read the page from. * - * The callback shall set *pageTLI to the TLI of the file the page was - * read from. It is currently used only for error reporting purposes, to - * reconstruct the name of the WAL file where an error occurred. + * The callback shall set ->readPageTLI to the TLI of the file the page + * was read from. */ XLogPageReadCB read_page; diff --git a/src/include/access/xlogutils.h b/src/include/access/xlogutils.h index 4105b59904..4fb305bafd 100644 --- a/src/include/access/xlogutils.h +++ b/src/include/access/xlogutils.h @@ -47,12 +47,11 @@ extern Buffer XLogReadBufferExtended(RelFileNode rnode, ForkNumber forknum, extern Relation CreateFakeRelcacheEntry(RelFileNode rnode); extern void FreeFakeRelcacheEntry(Relation fakerel); + extern int read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, - XLogRecPtr targetRecPtr, char *cur_page, - TimeLineID *pageTLI); + XLogRecPtr targetRecPtr, char *cur_page); extern void XLogReadDetermineTimeline(XLogReaderState *state, XLogRecPtr wantPage, uint32 wantLength); - #endif diff --git a/src/include/replication/logicalfuncs.h b/src/include/replication/logicalfuncs.h index a9c178a9e6..012096f183 100644 --- a/src/include/replication/logicalfuncs.h +++ b/src/include/replication/logicalfuncs.h @@ -14,6 +14,6 @@ extern int logical_read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, XLogRecPtr targetRecPtr, - char *cur_page, TimeLineID *pageTLI); + char *cur_page); #endif -- 2.16.4 --=-=-= Content-Type: text/x-diff Content-Disposition: attachment; filename=v04-0003-Introduce-XLogSegment-structure.patch ^ permalink raw reply [nested|flat] 15+ messages in thread
* [PATCH 1/4] Remove TLI from some argument lists. @ 2019-09-09 09:53 Antonin Houska <ah@cybertec.at> 0 siblings, 0 replies; 15+ messages in thread From: Antonin Houska @ 2019-09-09 09:53 UTC (permalink / raw) The timeline information is available to caller via XLogReaderState. Now that XLogRead() is gonna be (sometimes) responsible for determining the TLI, it would have to be added the (TimeLineID *) argument too, just to be consistent with the current coding style. Since XLogRead() updates also other position-specific fields of XLogReaderState, it seems simpler if we remove the output argument from XLogPageReadCB and always report the TLI via XLogReaderState. --- src/backend/access/transam/xlog.c | 7 +++---- src/backend/access/transam/xlogreader.c | 6 +++--- src/backend/access/transam/xlogutils.c | 11 ++++++----- src/backend/replication/logical/logicalfuncs.c | 4 ++-- src/backend/replication/walsender.c | 2 +- src/bin/pg_rewind/parsexlog.c | 9 ++++----- src/bin/pg_waldump/pg_waldump.c | 2 +- src/include/access/xlogreader.h | 8 +++----- src/include/access/xlogutils.h | 5 ++--- src/include/replication/logicalfuncs.h | 2 +- 10 files changed, 26 insertions(+), 30 deletions(-) diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index 6876537b62..cd948dbefc 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -885,8 +885,7 @@ static int XLogFileRead(XLogSegNo segno, int emode, TimeLineID tli, int source, bool notfoundOk); static int XLogFileReadAnyTLI(XLogSegNo segno, int emode, int source); static int XLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *readBuf, - TimeLineID *readTLI); + int reqLen, XLogRecPtr targetRecPtr, char *readBuf); static bool WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess, bool fetching_ckpt, XLogRecPtr tliRecPtr); static int emode_for_corrupt_record(int emode, XLogRecPtr RecPtr); @@ -11523,7 +11522,7 @@ CancelBackup(void) */ static int XLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, int reqLen, - XLogRecPtr targetRecPtr, char *readBuf, TimeLineID *readTLI) + XLogRecPtr targetRecPtr, char *readBuf) { XLogPageReadPrivate *private = (XLogPageReadPrivate *) xlogreader->private_data; @@ -11640,7 +11639,7 @@ retry: Assert(targetPageOff == readOff); Assert(reqLen <= readLen); - *readTLI = curFileTLI; + xlogreader->readPageTLI = curFileTLI; /* * Check the page header immediately, so that we can retry immediately if diff --git a/src/backend/access/transam/xlogreader.c b/src/backend/access/transam/xlogreader.c index a66e3324b1..2184f4291d 100644 --- a/src/backend/access/transam/xlogreader.c +++ b/src/backend/access/transam/xlogreader.c @@ -559,7 +559,7 @@ ReadPageInternal(XLogReaderState *state, XLogRecPtr pageptr, int reqLen) readLen = state->read_page(state, targetSegmentPtr, XLOG_BLCKSZ, state->currRecPtr, - state->readBuf, &state->readPageTLI); + state->readBuf); if (readLen < 0) goto err; @@ -577,7 +577,7 @@ ReadPageInternal(XLogReaderState *state, XLogRecPtr pageptr, int reqLen) */ readLen = state->read_page(state, pageptr, Max(reqLen, SizeOfXLogShortPHD), state->currRecPtr, - state->readBuf, &state->readPageTLI); + state->readBuf); if (readLen < 0) goto err; @@ -596,7 +596,7 @@ ReadPageInternal(XLogReaderState *state, XLogRecPtr pageptr, int reqLen) { readLen = state->read_page(state, pageptr, XLogPageHeaderSize(hdr), state->currRecPtr, - state->readBuf, &state->readPageTLI); + state->readBuf); if (readLen < 0) goto err; } diff --git a/src/backend/access/transam/xlogutils.c b/src/backend/access/transam/xlogutils.c index 1fc39333f1..680bed8278 100644 --- a/src/backend/access/transam/xlogutils.c +++ b/src/backend/access/transam/xlogutils.c @@ -909,12 +909,12 @@ XLogReadDetermineTimeline(XLogReaderState *state, XLogRecPtr wantPage, uint32 wa */ int read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *cur_page, - TimeLineID *pageTLI) + int reqLen, XLogRecPtr targetRecPtr, char *cur_page) { XLogRecPtr read_upto, loc; int count; + TimeLineID pageTLI; loc = targetPagePtr + reqLen; @@ -934,7 +934,7 @@ read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, else read_upto = GetXLogReplayRecPtr(&ThisTimeLineID); - *pageTLI = ThisTimeLineID; + pageTLI = ThisTimeLineID; /* * Check which timeline to get the record from. @@ -991,7 +991,7 @@ read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, * nothing cares so long as the timeline doesn't go backwards. We * should read the page header instead; FIXME someday. */ - *pageTLI = state->currTLI; + pageTLI = state->currTLI; /* No need to wait on a historical timeline */ break; @@ -1022,8 +1022,9 @@ read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, * as 'count', read the whole page anyway. It's guaranteed to be * zero-padded up to the page boundary if it's incomplete. */ - XLogRead(cur_page, state->wal_segment_size, *pageTLI, targetPagePtr, + XLogRead(cur_page, state->wal_segment_size, pageTLI, targetPagePtr, XLOG_BLCKSZ); + state->readPageTLI = pageTLI; /* number of valid bytes in the buffer */ return count; diff --git a/src/backend/replication/logical/logicalfuncs.c b/src/backend/replication/logical/logicalfuncs.c index d974400d6e..d1cf80d441 100644 --- a/src/backend/replication/logical/logicalfuncs.c +++ b/src/backend/replication/logical/logicalfuncs.c @@ -116,10 +116,10 @@ check_permissions(void) int logical_read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *cur_page, TimeLineID *pageTLI) + int reqLen, XLogRecPtr targetRecPtr, char *cur_page) { return read_local_xlog_page(state, targetPagePtr, reqLen, - targetRecPtr, cur_page, pageTLI); + targetRecPtr, cur_page); } /* diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c index 23870a25a5..28d8c31af8 100644 --- a/src/backend/replication/walsender.c +++ b/src/backend/replication/walsender.c @@ -763,7 +763,7 @@ StartReplication(StartReplicationCmd *cmd) */ static int logical_read_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, - XLogRecPtr targetRecPtr, char *cur_page, TimeLineID *pageTLI) + XLogRecPtr targetRecPtr, char *cur_page) { XLogRecPtr flushptr; int count; diff --git a/src/bin/pg_rewind/parsexlog.c b/src/bin/pg_rewind/parsexlog.c index 63c3879ead..0a89f9c02a 100644 --- a/src/bin/pg_rewind/parsexlog.c +++ b/src/bin/pg_rewind/parsexlog.c @@ -47,10 +47,10 @@ typedef struct XLogPageReadPrivate int tliIndex; } XLogPageReadPrivate; + static int SimpleXLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *readBuf, - TimeLineID *pageTLI); + int reqLen, XLogRecPtr targetRecPtr, char *readBuf); /* * Read WAL from the datadir/pg_wal, starting from 'startpoint' on timeline @@ -237,8 +237,7 @@ findLastCheckpoint(const char *datadir, XLogRecPtr forkptr, int tliIndex, /* XLogReader callback function, to read a WAL page */ static int SimpleXLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *readBuf, - TimeLineID *pageTLI) + int reqLen, XLogRecPtr targetRecPtr, char *readBuf) { XLogPageReadPrivate *private = (XLogPageReadPrivate *) xlogreader->private_data; uint32 targetPageOff; @@ -321,7 +320,7 @@ SimpleXLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, Assert(targetSegNo == xlogreadsegno); - *pageTLI = targetHistory[private->tliIndex].tli; + xlogreader->readPageTLI = targetHistory[private->tliIndex].tli; return XLOG_BLCKSZ; } diff --git a/src/bin/pg_waldump/pg_waldump.c b/src/bin/pg_waldump/pg_waldump.c index b95d467805..40c64a0bbf 100644 --- a/src/bin/pg_waldump/pg_waldump.c +++ b/src/bin/pg_waldump/pg_waldump.c @@ -423,7 +423,7 @@ XLogDumpXLogRead(const char *directory, TimeLineID timeline_id, */ static int XLogDumpReadPage(XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, - XLogRecPtr targetPtr, char *readBuff, TimeLineID *curFileTLI) + XLogRecPtr targetPtr, char *readBuff) { XLogDumpPrivate *private = state->private_data; int count = XLOG_BLCKSZ; diff --git a/src/include/access/xlogreader.h b/src/include/access/xlogreader.h index 735b1bd2fd..d64a9ad82f 100644 --- a/src/include/access/xlogreader.h +++ b/src/include/access/xlogreader.h @@ -38,8 +38,7 @@ typedef int (*XLogPageReadCB) (XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, int reqLen, XLogRecPtr targetRecPtr, - char *readBuf, - TimeLineID *pageTLI); + char *readBuf); typedef struct { @@ -99,9 +98,8 @@ struct XLogReaderState * actual WAL record it's interested in. In that case, targetRecPtr can * be used to determine which timeline to read the page from. * - * The callback shall set *pageTLI to the TLI of the file the page was - * read from. It is currently used only for error reporting purposes, to - * reconstruct the name of the WAL file where an error occurred. + * The callback shall set ->readPageTLI to the TLI of the file the page + * was read from. */ XLogPageReadCB read_page; diff --git a/src/include/access/xlogutils.h b/src/include/access/xlogutils.h index 4105b59904..4fb305bafd 100644 --- a/src/include/access/xlogutils.h +++ b/src/include/access/xlogutils.h @@ -47,12 +47,11 @@ extern Buffer XLogReadBufferExtended(RelFileNode rnode, ForkNumber forknum, extern Relation CreateFakeRelcacheEntry(RelFileNode rnode); extern void FreeFakeRelcacheEntry(Relation fakerel); + extern int read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, - XLogRecPtr targetRecPtr, char *cur_page, - TimeLineID *pageTLI); + XLogRecPtr targetRecPtr, char *cur_page); extern void XLogReadDetermineTimeline(XLogReaderState *state, XLogRecPtr wantPage, uint32 wantLength); - #endif diff --git a/src/include/replication/logicalfuncs.h b/src/include/replication/logicalfuncs.h index a9c178a9e6..012096f183 100644 --- a/src/include/replication/logicalfuncs.h +++ b/src/include/replication/logicalfuncs.h @@ -14,6 +14,6 @@ extern int logical_read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, XLogRecPtr targetRecPtr, - char *cur_page, TimeLineID *pageTLI); + char *cur_page); #endif -- 2.22.0 --=-=-= Content-Type: text/x-diff Content-Disposition: attachment; filename=v05-0003-Introduce-XLogSegment-structure.patch ^ permalink raw reply [nested|flat] 15+ messages in thread
* [PATCH 2/6] Remove TLI from some argument lists. @ 2019-09-23 05:40 Antonin Houska <ah@cybertec.at> 0 siblings, 0 replies; 15+ messages in thread From: Antonin Houska @ 2019-09-23 05:40 UTC (permalink / raw) The timeline information is available to caller via XLogReaderState. Now that XLogRead() is gonna be (sometimes) responsible for determining the TLI, it would have to be added the (TimeLineID *) argument too, just to be consistent with the current coding style. Since XLogRead() updates also other position-specific fields of XLogReaderState, it seems simpler if we remove the output argument from XLogPageReadCB and always report the TLI via XLogReaderState. --- src/backend/access/transam/xlog.c | 7 +++---- src/backend/access/transam/xlogreader.c | 6 +++--- src/backend/access/transam/xlogutils.c | 11 ++++++----- src/backend/replication/logical/logicalfuncs.c | 4 ++-- src/backend/replication/walsender.c | 2 +- src/bin/pg_rewind/parsexlog.c | 8 +++----- src/bin/pg_waldump/pg_waldump.c | 2 +- src/include/access/xlogreader.h | 8 +++----- src/include/access/xlogutils.h | 5 ++--- src/include/replication/logicalfuncs.h | 2 +- 10 files changed, 25 insertions(+), 30 deletions(-) diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index b7ff004234..7a89dfed7f 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -885,8 +885,7 @@ static int XLogFileRead(XLogSegNo segno, int emode, TimeLineID tli, int source, bool notfoundOk); static int XLogFileReadAnyTLI(XLogSegNo segno, int emode, int source); static int XLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *readBuf, - TimeLineID *readTLI); + int reqLen, XLogRecPtr targetRecPtr, char *readBuf); static bool WaitForWALToBecomeAvailable(XLogRecPtr RecPtr, bool randAccess, bool fetching_ckpt, XLogRecPtr tliRecPtr); static int emode_for_corrupt_record(int emode, XLogRecPtr RecPtr); @@ -11523,7 +11522,7 @@ CancelBackup(void) */ static int XLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, int reqLen, - XLogRecPtr targetRecPtr, char *readBuf, TimeLineID *readTLI) + XLogRecPtr targetRecPtr, char *readBuf) { XLogPageReadPrivate *private = (XLogPageReadPrivate *) xlogreader->private_data; @@ -11640,7 +11639,7 @@ retry: Assert(targetPageOff == readOff); Assert(reqLen <= readLen); - *readTLI = curFileTLI; + xlogreader->readPageTLI = curFileTLI; /* * Check the page header immediately, so that we can retry immediately if diff --git a/src/backend/access/transam/xlogreader.c b/src/backend/access/transam/xlogreader.c index a66e3324b1..2184f4291d 100644 --- a/src/backend/access/transam/xlogreader.c +++ b/src/backend/access/transam/xlogreader.c @@ -559,7 +559,7 @@ ReadPageInternal(XLogReaderState *state, XLogRecPtr pageptr, int reqLen) readLen = state->read_page(state, targetSegmentPtr, XLOG_BLCKSZ, state->currRecPtr, - state->readBuf, &state->readPageTLI); + state->readBuf); if (readLen < 0) goto err; @@ -577,7 +577,7 @@ ReadPageInternal(XLogReaderState *state, XLogRecPtr pageptr, int reqLen) */ readLen = state->read_page(state, pageptr, Max(reqLen, SizeOfXLogShortPHD), state->currRecPtr, - state->readBuf, &state->readPageTLI); + state->readBuf); if (readLen < 0) goto err; @@ -596,7 +596,7 @@ ReadPageInternal(XLogReaderState *state, XLogRecPtr pageptr, int reqLen) { readLen = state->read_page(state, pageptr, XLogPageHeaderSize(hdr), state->currRecPtr, - state->readBuf, &state->readPageTLI); + state->readBuf); if (readLen < 0) goto err; } diff --git a/src/backend/access/transam/xlogutils.c b/src/backend/access/transam/xlogutils.c index 1fc39333f1..680bed8278 100644 --- a/src/backend/access/transam/xlogutils.c +++ b/src/backend/access/transam/xlogutils.c @@ -909,12 +909,12 @@ XLogReadDetermineTimeline(XLogReaderState *state, XLogRecPtr wantPage, uint32 wa */ int read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *cur_page, - TimeLineID *pageTLI) + int reqLen, XLogRecPtr targetRecPtr, char *cur_page) { XLogRecPtr read_upto, loc; int count; + TimeLineID pageTLI; loc = targetPagePtr + reqLen; @@ -934,7 +934,7 @@ read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, else read_upto = GetXLogReplayRecPtr(&ThisTimeLineID); - *pageTLI = ThisTimeLineID; + pageTLI = ThisTimeLineID; /* * Check which timeline to get the record from. @@ -991,7 +991,7 @@ read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, * nothing cares so long as the timeline doesn't go backwards. We * should read the page header instead; FIXME someday. */ - *pageTLI = state->currTLI; + pageTLI = state->currTLI; /* No need to wait on a historical timeline */ break; @@ -1022,8 +1022,9 @@ read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, * as 'count', read the whole page anyway. It's guaranteed to be * zero-padded up to the page boundary if it's incomplete. */ - XLogRead(cur_page, state->wal_segment_size, *pageTLI, targetPagePtr, + XLogRead(cur_page, state->wal_segment_size, pageTLI, targetPagePtr, XLOG_BLCKSZ); + state->readPageTLI = pageTLI; /* number of valid bytes in the buffer */ return count; diff --git a/src/backend/replication/logical/logicalfuncs.c b/src/backend/replication/logical/logicalfuncs.c index d974400d6e..d1cf80d441 100644 --- a/src/backend/replication/logical/logicalfuncs.c +++ b/src/backend/replication/logical/logicalfuncs.c @@ -116,10 +116,10 @@ check_permissions(void) int logical_read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *cur_page, TimeLineID *pageTLI) + int reqLen, XLogRecPtr targetRecPtr, char *cur_page) { return read_local_xlog_page(state, targetPagePtr, reqLen, - targetRecPtr, cur_page, pageTLI); + targetRecPtr, cur_page); } /* diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c index 23870a25a5..28d8c31af8 100644 --- a/src/backend/replication/walsender.c +++ b/src/backend/replication/walsender.c @@ -763,7 +763,7 @@ StartReplication(StartReplicationCmd *cmd) */ static int logical_read_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, - XLogRecPtr targetRecPtr, char *cur_page, TimeLineID *pageTLI) + XLogRecPtr targetRecPtr, char *cur_page) { XLogRecPtr flushptr; int count; diff --git a/src/bin/pg_rewind/parsexlog.c b/src/bin/pg_rewind/parsexlog.c index 63c3879ead..33e2ba2a03 100644 --- a/src/bin/pg_rewind/parsexlog.c +++ b/src/bin/pg_rewind/parsexlog.c @@ -49,8 +49,7 @@ typedef struct XLogPageReadPrivate static int SimpleXLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *readBuf, - TimeLineID *pageTLI); + int reqLen, XLogRecPtr targetRecPtr, char *readBuf); /* * Read WAL from the datadir/pg_wal, starting from 'startpoint' on timeline @@ -237,8 +236,7 @@ findLastCheckpoint(const char *datadir, XLogRecPtr forkptr, int tliIndex, /* XLogReader callback function, to read a WAL page */ static int SimpleXLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, - int reqLen, XLogRecPtr targetRecPtr, char *readBuf, - TimeLineID *pageTLI) + int reqLen, XLogRecPtr targetRecPtr, char *readBuf) { XLogPageReadPrivate *private = (XLogPageReadPrivate *) xlogreader->private_data; uint32 targetPageOff; @@ -321,7 +319,7 @@ SimpleXLogPageRead(XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, Assert(targetSegNo == xlogreadsegno); - *pageTLI = targetHistory[private->tliIndex].tli; + xlogreader->readPageTLI = targetHistory[private->tliIndex].tli; return XLOG_BLCKSZ; } diff --git a/src/bin/pg_waldump/pg_waldump.c b/src/bin/pg_waldump/pg_waldump.c index b95d467805..40c64a0bbf 100644 --- a/src/bin/pg_waldump/pg_waldump.c +++ b/src/bin/pg_waldump/pg_waldump.c @@ -423,7 +423,7 @@ XLogDumpXLogRead(const char *directory, TimeLineID timeline_id, */ static int XLogDumpReadPage(XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, - XLogRecPtr targetPtr, char *readBuff, TimeLineID *curFileTLI) + XLogRecPtr targetPtr, char *readBuff) { XLogDumpPrivate *private = state->private_data; int count = XLOG_BLCKSZ; diff --git a/src/include/access/xlogreader.h b/src/include/access/xlogreader.h index 735b1bd2fd..d64a9ad82f 100644 --- a/src/include/access/xlogreader.h +++ b/src/include/access/xlogreader.h @@ -38,8 +38,7 @@ typedef int (*XLogPageReadCB) (XLogReaderState *xlogreader, XLogRecPtr targetPagePtr, int reqLen, XLogRecPtr targetRecPtr, - char *readBuf, - TimeLineID *pageTLI); + char *readBuf); typedef struct { @@ -99,9 +98,8 @@ struct XLogReaderState * actual WAL record it's interested in. In that case, targetRecPtr can * be used to determine which timeline to read the page from. * - * The callback shall set *pageTLI to the TLI of the file the page was - * read from. It is currently used only for error reporting purposes, to - * reconstruct the name of the WAL file where an error occurred. + * The callback shall set ->readPageTLI to the TLI of the file the page + * was read from. */ XLogPageReadCB read_page; diff --git a/src/include/access/xlogutils.h b/src/include/access/xlogutils.h index 4105b59904..4fb305bafd 100644 --- a/src/include/access/xlogutils.h +++ b/src/include/access/xlogutils.h @@ -47,12 +47,11 @@ extern Buffer XLogReadBufferExtended(RelFileNode rnode, ForkNumber forknum, extern Relation CreateFakeRelcacheEntry(RelFileNode rnode); extern void FreeFakeRelcacheEntry(Relation fakerel); + extern int read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, - XLogRecPtr targetRecPtr, char *cur_page, - TimeLineID *pageTLI); + XLogRecPtr targetRecPtr, char *cur_page); extern void XLogReadDetermineTimeline(XLogReaderState *state, XLogRecPtr wantPage, uint32 wantLength); - #endif diff --git a/src/include/replication/logicalfuncs.h b/src/include/replication/logicalfuncs.h index a9c178a9e6..012096f183 100644 --- a/src/include/replication/logicalfuncs.h +++ b/src/include/replication/logicalfuncs.h @@ -14,6 +14,6 @@ extern int logical_read_local_xlog_page(XLogReaderState *state, XLogRecPtr targetPagePtr, int reqLen, XLogRecPtr targetRecPtr, - char *cur_page, TimeLineID *pageTLI); + char *cur_page); #endif -- 2.20.1 --=-=-= Content-Type: text/x-diff Content-Disposition: attachment; filename=v06-0003-Introduce-WALOpenSegment-structure.patch ^ permalink raw reply [nested|flat] 15+ messages in thread
* [PATCH v1 5/7] Row pattern recognition patch (docs). @ 2023-06-25 11:48 Tatsuo Ishii <ishii@postgresql.org> 0 siblings, 0 replies; 15+ messages in thread From: Tatsuo Ishii @ 2023-06-25 11:48 UTC (permalink / raw) --- doc/src/sgml/advanced.sgml | 51 ++++++++++++++++++++++++++ doc/src/sgml/func.sgml | 69 ++++++++++++++++++++++++++++++++++++ doc/src/sgml/ref/select.sgml | 18 ++++++++-- 3 files changed, 136 insertions(+), 2 deletions(-) diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml index 755c9f1485..23ee285b40 100644 --- a/doc/src/sgml/advanced.sgml +++ b/doc/src/sgml/advanced.sgml @@ -537,6 +537,57 @@ WHERE pos < 3; <literal>rank</literal> less than 3. </para> + <para> + Window function <function>rpr</function> can be used with row pattern + common syntax to perform row pattern recognition in a query. Row pattern + common syntax includes two sub clauses. <literal>DEFINE</literal> defines + definition variables along with an expression. The expression must be a + logical expression, which means it must + return <literal>TRUE</literal>, <literal>FALSE</literal> + or <literal>NULL</literal>. Moreover if the expression comprises a column + reference, it must be the argument of <function>rpr</function>. An + example of <literal>DEFINE</literal> is as follows. + +<programlisting> +DEFINE + LOWPRICE AS price <= 100, + UP AS price > PREV(price), + DOWN AS price < PREV(price) +</programlisting> + + Note that <function>PREV</function> returns price column in the previous + row if it's called in a context of row pattern recognition. So in the + second line means the definition variable "UP" is <literal>TRUE</literal> + when price column in the current row is greater than the price column in + the previous row. Likewise, "DOWN" is <literal>TRUE</literal> when when + price column in the current row is lower than the price column in the + previous row. + </para> + <para> + Once <literal>DEFINE</literal> exists, <literal>PATTERN</literal> can be + used. <literal>PATTERN</literal> defines a sequence of rows that satisfies + certain conditions. For example following <literal>PATTERN</literal> + defines that a row starts with the condition "LOWPRICE", then one or more + rows satisfy "UP" and finally one or more rows satisfy "DOWN". If a + sequence of rows found, rpr returns the column at the starting row. + Example of a <literal>SELECT</literal> using the <literal>DEFINE</literal> + and <literal>PATTERN</literal> clause is as follows. + +<programlisting> +SELECT company, tdate, price, rpr(price) OVER w FROM stock + WINDOW w AS ( + PARTITION BY company + ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING + INITIAL + PATTERN (LOWPRICE UP+ DOWN+) + DEFINE + LOWPRICE AS price <= 100, + UP AS price > PREV(price), + DOWN AS price < PREV(price) +); +</programlisting> + </para> + <para> When a query involves multiple window functions, it is possible to write out each one with a separate <literal>OVER</literal> clause, but this is diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml index 5a47ce4343..8069c58ca5 100644 --- a/doc/src/sgml/func.sgml +++ b/doc/src/sgml/func.sgml @@ -21648,6 +21648,22 @@ SELECT count(*) FROM sometable; returns <literal>NULL</literal> if there is no such row. </para></entry> </row> + + <row> + <entry role="func_table_entry"><para role="func_signature"> + <indexterm> + <primary>rpr</primary> + </indexterm> + <function>rpr</function> ( <parameter>value</parameter> <type>anyelement</type> ) + <returnvalue>anyelement</returnvalue> + </para> + <para> + Perform row pattern recognition using column specified + by <parameter>value</parameter> and returns the value of the column if + current row is the first matching row; + returns <literal>NULL</literal> otherwise. + </para></entry> + </row> </tbody> </tgroup> </table> @@ -21687,6 +21703,59 @@ SELECT count(*) FROM sometable; Other frame specifications can be used to obtain other effects. </para> + <para> + Row pattern recognition navigation functions are listed in + <xref linkend="functions-rpr-navigation-table"/>. These functions + can be used to describe DEFINE clause of Row pattern recognition. + </para> + + <table id="functions-rpr-navigation-table"> + <title>Row Pattern Navigation Functions</title> + <tgroup cols="1"> + <thead> + <row> + <entry role="func_table_entry"><para role="func_signature"> + Function + </para> + <para> + Description + </para></entry> + </row> + </thead> + + <tbody> + <row> + <entry role="func_table_entry"><para role="func_signature"> + <indexterm> + <primary>prev</primary> + </indexterm> + <function>prev</function> ( <parameter>value</parameter> <type>anyelement</type> ) + <returnvalue>anyelement</returnvalue> + </para> + <para> + Returns the column value at the previous row; + returns NULL if there is no previous row in the window frame. + </para></entry> + </row> + + <row> + <entry role="func_table_entry"><para role="func_signature"> + <indexterm> + <primary>next</primary> + </indexterm> + <function>next</function> ( <parameter>value</parameter> <type>anyelement</type> ) + <returnvalue>anyelement</returnvalue> + </para> + <para> + Returns the column value at the next row; + returns NULL if there is no next row in the window frame. + </para></entry> + </row> + + </tbody> + </tgroup> + </table> + <note> <para> The SQL standard defines a <literal>RESPECT NULLS</literal> or diff --git a/doc/src/sgml/ref/select.sgml b/doc/src/sgml/ref/select.sgml index 0ee0cc7e64..c0fc16d773 100644 --- a/doc/src/sgml/ref/select.sgml +++ b/doc/src/sgml/ref/select.sgml @@ -966,8 +966,8 @@ WINDOW <replaceable class="parameter">window_name</replaceable> AS ( <replaceabl The <replaceable class="parameter">frame_clause</replaceable> can be one of <synopsis> -{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] -{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] +{ RANGE | ROWS | GROUPS } <replaceable>frame_start</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax] +{ RANGE | ROWS | GROUPS } BETWEEN <replaceable>frame_start</replaceable> AND <replaceable>frame_end</replaceable> [ <replaceable>frame_exclusion</replaceable> ] [row_pattern_common_syntax] </synopsis> where <replaceable>frame_start</replaceable> @@ -1074,6 +1074,20 @@ EXCLUDE NO OTHERS a given peer group will be in the frame or excluded from it. </para> + <para> + The + optional <replaceable class="parameter">row_pattern_common_syntax</replaceable> + defines the <firstterm>row pattern recognition condition</firstterm> for + this + window. <replaceable class="parameter">row_pattern_common_syntax</replaceable> + includes following subclauses. + +<synopsis> +PATTERN <replaceable class="parameter">pattern_variable_name</replaceable>[+] [, ...] +DEFINE <replaceable class="parameter">definition_varible_name</replaceable> AS <replaceable class="parameter">expression</replaceable> [, ...] +</synopsis> + </para> + <para> The purpose of a <literal>WINDOW</literal> clause is to specify the behavior of <firstterm>window functions</firstterm> appearing in the query's -- 2.25.1 ----Next_Part(Sun_Jun_25_21_05_09_2023_126)-- Content-Type: Text/X-Patch; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="v1-0006-Row-pattern-recognition-patch-tests.patch" ^ permalink raw reply [nested|flat] 15+ messages in thread
* [PATCH v6 3/5] Add GUC to specify non-transactional statistics flush interval @ 2026-01-28 07:53 Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 0 siblings, 0 replies; 15+ messages in thread From: Bertrand Drouvot @ 2026-01-28 07:53 UTC (permalink / raw) Adding pgstat_flush_interval, a new GUC to set the interval between flushes of non-transactional statistics. --- doc/src/sgml/config.sgml | 34 +++++++++++++++++++ src/backend/utils/activity/pgstat.c | 16 +++++++++ src/backend/utils/misc/guc_parameters.dat | 10 ++++++ src/backend/utils/misc/postgresql.conf.sample | 1 + src/include/pgstat.h | 6 ++-- src/include/utils/guc_hooks.h | 1 + 6 files changed, 64 insertions(+), 4 deletions(-) 59.1% doc/src/sgml/ 14.2% src/backend/utils/activity/ 14.5% src/backend/utils/misc/ 12.0% src/include/ diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index f1af1505cf3..20666679f90 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -8871,6 +8871,40 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; </listitem> </varlistentry> + <varlistentry id="guc-stats-flush-interval" xreflabel="stats_flush_interval"> + <term><varname>stats_flush_interval</varname> (<type>integer</type>) + <indexterm> + <primary><varname>stats_flush_interval</varname> configuration parameter</primary> + </indexterm> + </term> + <listitem> + <para> + Sets the interval at which statistics that can be updated while a + transaction is still running are made visible. These include, for example, + WAL activity and I/O operations. + Such statistics are refreshed at the specified interval and can be observed + during active transactions in monitoring views such as + <link linkend="monitoring-pg-stat-io-view"><structname>pg_stat_io</structname></link> + and + <link linkend="monitoring-pg-stat-wal-view"><structname>pg_stat_wal</structname></link>. + Other statistics are only made visible at transaction end and are not + affected by this setting. + If the value is specified without a unit, milliseconds are assumed. + The default is 10 seconds (<literal>10s</literal>), which is generally + the smallest practical value for long-running transactions. + </para> + <note> + <para> + This parameter does not affect statistics that are only reported at + transaction end, such as the columns of <structname>pg_stat_all_tables</structname> + (for example, <structfield>n_tup_ins</structfield>, <structfield>n_tup_upd</structfield>, + and <structfield>n_tup_del</structfield>). These statistics are always + flushed at the end of a transaction. + </para> + </note> + </listitem> + </varlistentry> + </variablelist> </sect2> diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index 411b65aae3e..79eb59b5625 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -123,6 +123,8 @@ * ---------- */ +/* minimum interval non-forced stats flushes.*/ +#define PGSTAT_MIN_INTERVAL 1000 /* how long until to block flushing pending stats updates */ #define PGSTAT_MAX_INTERVAL 60000 /* when to call pgstat_report_stat() again, even when idle */ @@ -203,6 +205,7 @@ static inline bool pgstat_is_kind_valid(PgStat_Kind kind); bool pgstat_track_counts = false; int pgstat_fetch_consistency = PGSTAT_FETCH_CONSISTENCY_CACHE; +int pgstat_flush_interval = 10000; /* ---------- @@ -2164,6 +2167,19 @@ assign_stats_fetch_consistency(int newval, void *extra) force_stats_snapshot_clear = true; } +/* + * GUC assign_hook for stats_flush_interval. + */ +void +assign_stats_flush_interval(int newval, void *extra) +{ + if (get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) + { + disable_timeout(ANYTIME_STATS_UPDATE_TIMEOUT, false); + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, newval); + } +} + /* * Flushes only FLUSH_ANYTIME stats using non-blocking locks. Transactional * stats (FLUSH_AT_TXN_BOUNDARY) remain pending until transaction boundary. diff --git a/src/backend/utils/misc/guc_parameters.dat b/src/backend/utils/misc/guc_parameters.dat index c1f1603cd39..fc0e4259b36 100644 --- a/src/backend/utils/misc/guc_parameters.dat +++ b/src/backend/utils/misc/guc_parameters.dat @@ -2789,6 +2789,16 @@ assign_hook => 'assign_stats_fetch_consistency', }, +{ name => 'stats_flush_interval', type => 'int', context => 'PGC_USERSET', group => 'STATS_CUMULATIVE', + short_desc => 'Sets the interval between flushes of non-transactional statistics.', + flags => 'GUC_UNIT_MS', + variable => 'pgstat_flush_interval', + boot_val => '10000', + min => '1000', + max => 'INT_MAX', + assign_hook => 'assign_stats_flush_interval' +}, + { name => 'subtransaction_buffers', type => 'int', context => 'PGC_POSTMASTER', group => 'RESOURCES_MEM', short_desc => 'Sets the size of the dedicated buffer pool used for the subtransaction cache.', long_desc => '0 means use a fraction of "shared_buffers".', diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index 1ae594af843..3f998a0bea0 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -673,6 +673,7 @@ #track_wal_io_timing = off #track_functions = none # none, pl, all #stats_fetch_consistency = cache # cache, none, snapshot +#stats_flush_interval = 10s # in milliseconds # - Monitoring - diff --git a/src/include/pgstat.h b/src/include/pgstat.h index b340a680614..ef856dbf55b 100644 --- a/src/include/pgstat.h +++ b/src/include/pgstat.h @@ -35,9 +35,6 @@ /* Default directory to store temporary statistics data in */ #define PG_STAT_TMP_DIR "pg_stat_tmp" -/* Minimum interval non-forced stats flushes */ -#define PGSTAT_MIN_INTERVAL 1000 - /* Values for track_functions GUC variable --- order is significant! */ typedef enum TrackFunctionsLevel { @@ -548,7 +545,7 @@ extern void pgstat_force_next_flush(void); #define pgstat_schedule_anytime_update() \ do { \ if (IsUnderPostmaster && !get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) \ - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); \ + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); \ } while (0) extern void pgstat_reset_counters(void); @@ -828,6 +825,7 @@ extern PgStat_WalStats *pgstat_fetch_stat_wal(void); extern PGDLLIMPORT bool pgstat_track_counts; extern PGDLLIMPORT int pgstat_track_functions; extern PGDLLIMPORT int pgstat_fetch_consistency; +extern PGDLLIMPORT int pgstat_flush_interval; /* diff --git a/src/include/utils/guc_hooks.h b/src/include/utils/guc_hooks.h index b6ecb0e769f..3a2ae6c41cd 100644 --- a/src/include/utils/guc_hooks.h +++ b/src/include/utils/guc_hooks.h @@ -132,6 +132,7 @@ extern bool check_session_authorization(char **newval, void **extra, GucSource s extern void assign_session_authorization(const char *newval, void *extra); extern void assign_session_replication_role(int newval, void *extra); extern void assign_stats_fetch_consistency(int newval, void *extra); +extern void assign_stats_flush_interval(int newval, void *extra); extern bool check_ssl(bool *newval, void **extra, GucSource source); extern bool check_stage_log_stats(bool *newval, void **extra, GucSource source); extern bool check_standard_conforming_strings(bool *newval, void **extra, -- 2.34.1 --DxqFthphbM+ha9Dy Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="v6-0004-Remove-useless-calls-to-flush-some-stats.patch" ^ permalink raw reply [nested|flat] 15+ messages in thread
* [PATCH v11 3/5] Add GUC to specify non-transactional statistics flush interval @ 2026-01-28 07:53 Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 0 siblings, 0 replies; 15+ messages in thread From: Bertrand Drouvot @ 2026-01-28 07:53 UTC (permalink / raw) Adding pgstat_flush_interval, a new GUC to set the interval between flushes of non-transactional statistics. --- doc/src/sgml/config.sgml | 32 +++++++++++++++++++ src/backend/utils/activity/pgstat.c | 13 ++++++++ src/backend/utils/misc/guc_parameters.dat | 10 ++++++ src/backend/utils/misc/postgresql.conf.sample | 1 + src/backend/utils/misc/timeout.c | 6 ++++ src/include/pgstat.h | 6 ++-- src/include/utils/guc_hooks.h | 1 + src/include/utils/timeout.h | 1 + .../test_custom_stats/t/001_custom_stats.pl | 6 ++-- 9 files changed, 70 insertions(+), 6 deletions(-) 51.0% doc/src/sgml/ 10.6% src/backend/utils/activity/ 15.9% src/backend/utils/misc/ 3.6% src/include/utils/ 9.0% src/include/ 9.6% src/test/modules/test_custom_stats/t/ diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 20dbcaeb3ee..1eed71007a7 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -8929,6 +8929,38 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; </listitem> </varlistentry> + <varlistentry id="guc-stats-flush-interval" xreflabel="stats_flush_interval"> + <term><varname>stats_flush_interval</varname> (<type>integer</type>) + <indexterm> + <primary><varname>stats_flush_interval</varname> configuration parameter</primary> + </indexterm> + </term> + <listitem> + <para> + Sets the interval at which certain statistics, which can be updated while a + transaction is in progress, are made visible. These include WAL activity + and I/O operations. + Such statistics are refreshed at the specified interval and can be observed + during active transactions in monitoring views such as + <link linkend="monitoring-pg-stat-wal-view"><structname>pg_stat_wal</structname></link> + and + <link linkend="monitoring-pg-stat-io-view"><structname>pg_stat_io</structname></link>. + If the value is specified without a unit, milliseconds are assumed. + The default is 10 seconds (<literal>10s</literal>), which is generally + the smallest practical value for long-running transactions. + </para> + <note> + <para> + This parameter does not affect statistics that are only reported at + transaction end, such as the columns of <structname>pg_stat_all_tables</structname> + (for example, <structfield>n_tup_ins</structfield>, <structfield>n_tup_upd</structfield>, + and <structfield>n_tup_del</structfield>). These statistics are always + flushed at the end of a transaction. + </para> + </note> + </listitem> + </varlistentry> + </variablelist> </sect2> diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index ddd331e2c81..fd6ab0db16f 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -124,6 +124,8 @@ * ---------- */ +/* minimum interval non-forced stats flushes.*/ +#define PGSTAT_MIN_INTERVAL 1000 /* how long until to block flushing pending stats updates */ #define PGSTAT_MAX_INTERVAL 60000 /* when to call pgstat_report_stat() again, even when idle */ @@ -204,6 +206,7 @@ static inline bool pgstat_is_kind_valid(PgStat_Kind kind); bool pgstat_track_counts = false; int pgstat_fetch_consistency = PGSTAT_FETCH_CONSISTENCY_CACHE; +int pgstat_flush_interval = 10000; /* ---------- @@ -2171,6 +2174,16 @@ assign_stats_fetch_consistency(int newval, void *extra) force_stats_snapshot_clear = true; } +/* + * GUC assign_hook for stats_flush_interval. + */ +void +assign_stats_flush_interval(int newval, void *extra) +{ + if (get_all_timeouts_initialized()) + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, newval); +} + /* * Flushes only FLUSH_ANYTIME stats using non-blocking locks. Transactional * stats (FLUSH_AT_TXN_BOUNDARY) remain pending until transaction boundary. diff --git a/src/backend/utils/misc/guc_parameters.dat b/src/backend/utils/misc/guc_parameters.dat index 9507778415d..073e08c7892 100644 --- a/src/backend/utils/misc/guc_parameters.dat +++ b/src/backend/utils/misc/guc_parameters.dat @@ -2801,6 +2801,16 @@ assign_hook => 'assign_stats_fetch_consistency', }, +{ name => 'stats_flush_interval', type => 'int', context => 'PGC_USERSET', group => 'STATS_CUMULATIVE', + short_desc => 'Sets the interval between flushes of non-transactional statistics.', + flags => 'GUC_UNIT_MS', + variable => 'pgstat_flush_interval', + boot_val => '10000', + min => '1000', + max => 'INT_MAX', + assign_hook => 'assign_stats_flush_interval' +}, + { name => 'subtransaction_buffers', type => 'int', context => 'PGC_POSTMASTER', group => 'RESOURCES_MEM', short_desc => 'Sets the size of the dedicated buffer pool used for the subtransaction cache.', long_desc => '0 means use a fraction of "shared_buffers".', diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index f938cc65a3a..8bd37a25b38 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -688,6 +688,7 @@ #track_wal_io_timing = off #track_functions = none # none, pl, all #stats_fetch_consistency = cache # cache, none, snapshot +#stats_flush_interval = 10s # in milliseconds # - Monitoring - diff --git a/src/backend/utils/misc/timeout.c b/src/backend/utils/misc/timeout.c index ddba5dc607c..85c4260d1db 100644 --- a/src/backend/utils/misc/timeout.c +++ b/src/backend/utils/misc/timeout.c @@ -828,3 +828,9 @@ get_timeout_finish_time(TimeoutId id) { return all_timeouts[id].fin_time; } + +bool +get_all_timeouts_initialized(void) +{ + return all_timeouts_initialized; +} diff --git a/src/include/pgstat.h b/src/include/pgstat.h index b011a315679..90237c70829 100644 --- a/src/include/pgstat.h +++ b/src/include/pgstat.h @@ -34,9 +34,6 @@ /* Default directory to store temporary statistics data in */ #define PG_STAT_TMP_DIR "pg_stat_tmp" -/* Minimum interval non-forced stats flushes */ -#define PGSTAT_MIN_INTERVAL 1000 - /* Values for track_functions GUC variable --- order is significant! */ typedef enum TrackFunctionsLevel { @@ -548,7 +545,7 @@ extern void pgstat_force_next_flush(void); do { \ if (IsUnderPostmaster && !pgstat_pending_anytime) \ { \ - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); \ + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); \ pgstat_pending_anytime = true; \ } \ } while (0) @@ -831,6 +828,7 @@ extern PGDLLIMPORT bool pgstat_pending_anytime; extern PGDLLIMPORT bool pgstat_track_counts; extern PGDLLIMPORT int pgstat_track_functions; extern PGDLLIMPORT int pgstat_fetch_consistency; +extern PGDLLIMPORT int pgstat_flush_interval; /* diff --git a/src/include/utils/guc_hooks.h b/src/include/utils/guc_hooks.h index 9c90670d9b8..9b5d2a90387 100644 --- a/src/include/utils/guc_hooks.h +++ b/src/include/utils/guc_hooks.h @@ -132,6 +132,7 @@ extern bool check_session_authorization(char **newval, void **extra, GucSource s extern void assign_session_authorization(const char *newval, void *extra); extern void assign_session_replication_role(int newval, void *extra); extern void assign_stats_fetch_consistency(int newval, void *extra); +extern void assign_stats_flush_interval(int newval, void *extra); extern bool check_ssl(bool *newval, void **extra, GucSource source); extern bool check_stage_log_stats(bool *newval, void **extra, GucSource source); extern bool check_standard_conforming_strings(bool *newval, void **extra, diff --git a/src/include/utils/timeout.h b/src/include/utils/timeout.h index 10723bb664c..fe7327de209 100644 --- a/src/include/utils/timeout.h +++ b/src/include/utils/timeout.h @@ -93,5 +93,6 @@ extern bool get_timeout_active(TimeoutId id); extern bool get_timeout_indicator(TimeoutId id, bool reset_indicator); extern TimestampTz get_timeout_start_time(TimeoutId id); extern TimestampTz get_timeout_finish_time(TimeoutId id); +extern bool get_all_timeouts_initialized(void); #endif /* TIMEOUT_H */ diff --git a/src/test/modules/test_custom_stats/t/001_custom_stats.pl b/src/test/modules/test_custom_stats/t/001_custom_stats.pl index 6ba4022418f..920443487c0 100644 --- a/src/test/modules/test_custom_stats/t/001_custom_stats.pl +++ b/src/test/modules/test_custom_stats/t/001_custom_stats.pl @@ -164,11 +164,12 @@ $node->safe_psql('postgres', q(select test_custom_stats_fixed_reset())); $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); my $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; SET LOCAL stats_fetch_consistency = none; -- Accumulate stats select test_custom_stats_fixed_anytime_update() from generate_series(1, 2); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select 'fixed_anytime:'||numcalls from test_custom_stats_fixed_report(); @@ -184,12 +185,13 @@ like($result, qr/^fixed_anytime:2/m, $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; SET LOCAL stats_fetch_consistency = none; -- Accumulate stats select test_custom_stats_var_anytime_update('entry2'); select test_custom_stats_var_anytime_update('entry2'); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select 'var_anytime:'||calls from test_custom_stats_var_report('entry2'); -- 2.34.1 --2MEBAGW8+kohXisi Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="v11-0004-Remove-useless-calls-to-flush-some-stats.patch" ^ permalink raw reply [nested|flat] 15+ messages in thread
* [PATCH v7 3/5] Add GUC to specify non-transactional statistics flush interval @ 2026-01-28 07:53 Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 0 siblings, 0 replies; 15+ messages in thread From: Bertrand Drouvot @ 2026-01-28 07:53 UTC (permalink / raw) Adding pgstat_flush_interval, a new GUC to set the interval between flushes of non-transactional statistics. --- doc/src/sgml/config.sgml | 32 +++++++++++++++++++ src/backend/utils/activity/pgstat.c | 16 ++++++++++ src/backend/utils/misc/guc_parameters.dat | 10 ++++++ src/backend/utils/misc/postgresql.conf.sample | 1 + src/include/pgstat.h | 6 ++-- src/include/utils/guc_hooks.h | 1 + .../test_custom_stats/t/001_custom_stats.pl | 6 ++-- 7 files changed, 66 insertions(+), 6 deletions(-) 51.8% doc/src/sgml/ 13.3% src/backend/utils/activity/ 13.6% src/backend/utils/misc/ 11.3% src/include/ 9.8% src/test/modules/test_custom_stats/t/ diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 6bc2690ce07..383bbe3a132 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -8923,6 +8923,38 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; </listitem> </varlistentry> + <varlistentry id="guc-stats-flush-interval" xreflabel="stats_flush_interval"> + <term><varname>stats_flush_interval</varname> (<type>integer</type>) + <indexterm> + <primary><varname>stats_flush_interval</varname> configuration parameter</primary> + </indexterm> + </term> + <listitem> + <para> + Sets the interval at which certain statistics, which can be updated while a + transaction is in progress, are made visible. These include WAL activity + and I/O operations. + Such statistics are refreshed at the specified interval and can be observed + during active transactions in monitoring views such as + <link linkend="monitoring-pg-stat-wal-view"><structname>pg_stat_wal</structname></link> + and + <link linkend="monitoring-pg-stat-io-view"><structname>pg_stat_io</structname></link>. + If the value is specified without a unit, milliseconds are assumed. + The default is 10 seconds (<literal>10s</literal>), which is generally + the smallest practical value for long-running transactions. + </para> + <note> + <para> + This parameter does not affect statistics that are only reported at + transaction end, such as the columns of <structname>pg_stat_all_tables</structname> + (for example, <structfield>n_tup_ins</structfield>, <structfield>n_tup_upd</structfield>, + and <structfield>n_tup_del</structfield>). These statistics are always + flushed at the end of a transaction. + </para> + </note> + </listitem> + </varlistentry> + </variablelist> </sect2> diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index a4ff64dc5ce..dd85a27c52f 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -123,6 +123,8 @@ * ---------- */ +/* minimum interval non-forced stats flushes.*/ +#define PGSTAT_MIN_INTERVAL 1000 /* how long until to block flushing pending stats updates */ #define PGSTAT_MAX_INTERVAL 60000 /* when to call pgstat_report_stat() again, even when idle */ @@ -203,6 +205,7 @@ static inline bool pgstat_is_kind_valid(PgStat_Kind kind); bool pgstat_track_counts = false; int pgstat_fetch_consistency = PGSTAT_FETCH_CONSISTENCY_CACHE; +int pgstat_flush_interval = 10000; /* ---------- @@ -2164,6 +2167,19 @@ assign_stats_fetch_consistency(int newval, void *extra) force_stats_snapshot_clear = true; } +/* + * GUC assign_hook for stats_flush_interval. + */ +void +assign_stats_flush_interval(int newval, void *extra) +{ + if (get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) + { + disable_timeout(ANYTIME_STATS_UPDATE_TIMEOUT, false); + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, newval); + } +} + /* * Flushes only FLUSH_ANYTIME stats using non-blocking locks. Transactional * stats (FLUSH_AT_TXN_BOUNDARY) remain pending until transaction boundary. diff --git a/src/backend/utils/misc/guc_parameters.dat b/src/backend/utils/misc/guc_parameters.dat index 271c033952e..d2734caafea 100644 --- a/src/backend/utils/misc/guc_parameters.dat +++ b/src/backend/utils/misc/guc_parameters.dat @@ -2801,6 +2801,16 @@ assign_hook => 'assign_stats_fetch_consistency', }, +{ name => 'stats_flush_interval', type => 'int', context => 'PGC_USERSET', group => 'STATS_CUMULATIVE', + short_desc => 'Sets the interval between flushes of non-transactional statistics.', + flags => 'GUC_UNIT_MS', + variable => 'pgstat_flush_interval', + boot_val => '10000', + min => '1000', + max => 'INT_MAX', + assign_hook => 'assign_stats_flush_interval' +}, + { name => 'subtransaction_buffers', type => 'int', context => 'PGC_POSTMASTER', group => 'RESOURCES_MEM', short_desc => 'Sets the size of the dedicated buffer pool used for the subtransaction cache.', long_desc => '0 means use a fraction of "shared_buffers".', diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index f938cc65a3a..8bd37a25b38 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -688,6 +688,7 @@ #track_wal_io_timing = off #track_functions = none # none, pl, all #stats_fetch_consistency = cache # cache, none, snapshot +#stats_flush_interval = 10s # in milliseconds # - Monitoring - diff --git a/src/include/pgstat.h b/src/include/pgstat.h index b340a680614..ef856dbf55b 100644 --- a/src/include/pgstat.h +++ b/src/include/pgstat.h @@ -35,9 +35,6 @@ /* Default directory to store temporary statistics data in */ #define PG_STAT_TMP_DIR "pg_stat_tmp" -/* Minimum interval non-forced stats flushes */ -#define PGSTAT_MIN_INTERVAL 1000 - /* Values for track_functions GUC variable --- order is significant! */ typedef enum TrackFunctionsLevel { @@ -548,7 +545,7 @@ extern void pgstat_force_next_flush(void); #define pgstat_schedule_anytime_update() \ do { \ if (IsUnderPostmaster && !get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) \ - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); \ + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); \ } while (0) extern void pgstat_reset_counters(void); @@ -828,6 +825,7 @@ extern PgStat_WalStats *pgstat_fetch_stat_wal(void); extern PGDLLIMPORT bool pgstat_track_counts; extern PGDLLIMPORT int pgstat_track_functions; extern PGDLLIMPORT int pgstat_fetch_consistency; +extern PGDLLIMPORT int pgstat_flush_interval; /* diff --git a/src/include/utils/guc_hooks.h b/src/include/utils/guc_hooks.h index 9c90670d9b8..9b5d2a90387 100644 --- a/src/include/utils/guc_hooks.h +++ b/src/include/utils/guc_hooks.h @@ -132,6 +132,7 @@ extern bool check_session_authorization(char **newval, void **extra, GucSource s extern void assign_session_authorization(const char *newval, void *extra); extern void assign_session_replication_role(int newval, void *extra); extern void assign_stats_fetch_consistency(int newval, void *extra); +extern void assign_stats_flush_interval(int newval, void *extra); extern bool check_ssl(bool *newval, void **extra, GucSource source); extern bool check_stage_log_stats(bool *newval, void **extra, GucSource source); extern bool check_standard_conforming_strings(bool *newval, void **extra, diff --git a/src/test/modules/test_custom_stats/t/001_custom_stats.pl b/src/test/modules/test_custom_stats/t/001_custom_stats.pl index 7be1b281776..22e2a75dcb9 100644 --- a/src/test/modules/test_custom_stats/t/001_custom_stats.pl +++ b/src/test/modules/test_custom_stats/t/001_custom_stats.pl @@ -164,10 +164,11 @@ $node->safe_psql('postgres', q(select test_custom_stats_fixed_reset())); $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); my $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; -- Accumulate stats select test_custom_stats_fixed_anytime_update() from generate_series(1, 2); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select 'anytime:'||numcalls from test_custom_stats_fixed_report(); @@ -183,11 +184,12 @@ like($result, qr/^anytime:2/m, $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; -- Accumulate stats select test_custom_stats_var_anytime_update('entry2'); select test_custom_stats_var_anytime_update('entry2'); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select * from test_custom_stats_var_report('entry2'); -- 2.34.1 --C2xzVbxFmVrP7k6O Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="v7-0004-Remove-useless-calls-to-flush-some-stats.patch" ^ permalink raw reply [nested|flat] 15+ messages in thread
* [PATCH v10 3/5] Add GUC to specify non-transactional statistics flush interval @ 2026-01-28 07:53 Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 0 siblings, 0 replies; 15+ messages in thread From: Bertrand Drouvot @ 2026-01-28 07:53 UTC (permalink / raw) Adding pgstat_flush_interval, a new GUC to set the interval between flushes of non-transactional statistics. --- doc/src/sgml/config.sgml | 32 +++++++++++++++++++ src/backend/utils/activity/pgstat.c | 13 ++++++++ src/backend/utils/misc/guc_parameters.dat | 10 ++++++ src/backend/utils/misc/postgresql.conf.sample | 1 + src/backend/utils/misc/timeout.c | 6 ++++ src/include/pgstat.h | 6 ++-- src/include/utils/guc_hooks.h | 1 + src/include/utils/timeout.h | 1 + .../test_custom_stats/t/001_custom_stats.pl | 6 ++-- 9 files changed, 70 insertions(+), 6 deletions(-) 51.0% doc/src/sgml/ 10.6% src/backend/utils/activity/ 15.9% src/backend/utils/misc/ 3.6% src/include/utils/ 9.0% src/include/ 9.6% src/test/modules/test_custom_stats/t/ diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 20dbcaeb3ee..1eed71007a7 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -8929,6 +8929,38 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; </listitem> </varlistentry> + <varlistentry id="guc-stats-flush-interval" xreflabel="stats_flush_interval"> + <term><varname>stats_flush_interval</varname> (<type>integer</type>) + <indexterm> + <primary><varname>stats_flush_interval</varname> configuration parameter</primary> + </indexterm> + </term> + <listitem> + <para> + Sets the interval at which certain statistics, which can be updated while a + transaction is in progress, are made visible. These include WAL activity + and I/O operations. + Such statistics are refreshed at the specified interval and can be observed + during active transactions in monitoring views such as + <link linkend="monitoring-pg-stat-wal-view"><structname>pg_stat_wal</structname></link> + and + <link linkend="monitoring-pg-stat-io-view"><structname>pg_stat_io</structname></link>. + If the value is specified without a unit, milliseconds are assumed. + The default is 10 seconds (<literal>10s</literal>), which is generally + the smallest practical value for long-running transactions. + </para> + <note> + <para> + This parameter does not affect statistics that are only reported at + transaction end, such as the columns of <structname>pg_stat_all_tables</structname> + (for example, <structfield>n_tup_ins</structfield>, <structfield>n_tup_upd</structfield>, + and <structfield>n_tup_del</structfield>). These statistics are always + flushed at the end of a transaction. + </para> + </note> + </listitem> + </varlistentry> + </variablelist> </sect2> diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index ddd331e2c81..fd6ab0db16f 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -124,6 +124,8 @@ * ---------- */ +/* minimum interval non-forced stats flushes.*/ +#define PGSTAT_MIN_INTERVAL 1000 /* how long until to block flushing pending stats updates */ #define PGSTAT_MAX_INTERVAL 60000 /* when to call pgstat_report_stat() again, even when idle */ @@ -204,6 +206,7 @@ static inline bool pgstat_is_kind_valid(PgStat_Kind kind); bool pgstat_track_counts = false; int pgstat_fetch_consistency = PGSTAT_FETCH_CONSISTENCY_CACHE; +int pgstat_flush_interval = 10000; /* ---------- @@ -2171,6 +2174,16 @@ assign_stats_fetch_consistency(int newval, void *extra) force_stats_snapshot_clear = true; } +/* + * GUC assign_hook for stats_flush_interval. + */ +void +assign_stats_flush_interval(int newval, void *extra) +{ + if (get_all_timeouts_initialized()) + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, newval); +} + /* * Flushes only FLUSH_ANYTIME stats using non-blocking locks. Transactional * stats (FLUSH_AT_TXN_BOUNDARY) remain pending until transaction boundary. diff --git a/src/backend/utils/misc/guc_parameters.dat b/src/backend/utils/misc/guc_parameters.dat index 9507778415d..073e08c7892 100644 --- a/src/backend/utils/misc/guc_parameters.dat +++ b/src/backend/utils/misc/guc_parameters.dat @@ -2801,6 +2801,16 @@ assign_hook => 'assign_stats_fetch_consistency', }, +{ name => 'stats_flush_interval', type => 'int', context => 'PGC_USERSET', group => 'STATS_CUMULATIVE', + short_desc => 'Sets the interval between flushes of non-transactional statistics.', + flags => 'GUC_UNIT_MS', + variable => 'pgstat_flush_interval', + boot_val => '10000', + min => '1000', + max => 'INT_MAX', + assign_hook => 'assign_stats_flush_interval' +}, + { name => 'subtransaction_buffers', type => 'int', context => 'PGC_POSTMASTER', group => 'RESOURCES_MEM', short_desc => 'Sets the size of the dedicated buffer pool used for the subtransaction cache.', long_desc => '0 means use a fraction of "shared_buffers".', diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index f938cc65a3a..8bd37a25b38 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -688,6 +688,7 @@ #track_wal_io_timing = off #track_functions = none # none, pl, all #stats_fetch_consistency = cache # cache, none, snapshot +#stats_flush_interval = 10s # in milliseconds # - Monitoring - diff --git a/src/backend/utils/misc/timeout.c b/src/backend/utils/misc/timeout.c index ddba5dc607c..85c4260d1db 100644 --- a/src/backend/utils/misc/timeout.c +++ b/src/backend/utils/misc/timeout.c @@ -828,3 +828,9 @@ get_timeout_finish_time(TimeoutId id) { return all_timeouts[id].fin_time; } + +bool +get_all_timeouts_initialized(void) +{ + return all_timeouts_initialized; +} diff --git a/src/include/pgstat.h b/src/include/pgstat.h index b011a315679..90237c70829 100644 --- a/src/include/pgstat.h +++ b/src/include/pgstat.h @@ -34,9 +34,6 @@ /* Default directory to store temporary statistics data in */ #define PG_STAT_TMP_DIR "pg_stat_tmp" -/* Minimum interval non-forced stats flushes */ -#define PGSTAT_MIN_INTERVAL 1000 - /* Values for track_functions GUC variable --- order is significant! */ typedef enum TrackFunctionsLevel { @@ -548,7 +545,7 @@ extern void pgstat_force_next_flush(void); do { \ if (IsUnderPostmaster && !pgstat_pending_anytime) \ { \ - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); \ + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); \ pgstat_pending_anytime = true; \ } \ } while (0) @@ -831,6 +828,7 @@ extern PGDLLIMPORT bool pgstat_pending_anytime; extern PGDLLIMPORT bool pgstat_track_counts; extern PGDLLIMPORT int pgstat_track_functions; extern PGDLLIMPORT int pgstat_fetch_consistency; +extern PGDLLIMPORT int pgstat_flush_interval; /* diff --git a/src/include/utils/guc_hooks.h b/src/include/utils/guc_hooks.h index 9c90670d9b8..9b5d2a90387 100644 --- a/src/include/utils/guc_hooks.h +++ b/src/include/utils/guc_hooks.h @@ -132,6 +132,7 @@ extern bool check_session_authorization(char **newval, void **extra, GucSource s extern void assign_session_authorization(const char *newval, void *extra); extern void assign_session_replication_role(int newval, void *extra); extern void assign_stats_fetch_consistency(int newval, void *extra); +extern void assign_stats_flush_interval(int newval, void *extra); extern bool check_ssl(bool *newval, void **extra, GucSource source); extern bool check_stage_log_stats(bool *newval, void **extra, GucSource source); extern bool check_standard_conforming_strings(bool *newval, void **extra, diff --git a/src/include/utils/timeout.h b/src/include/utils/timeout.h index 10723bb664c..fe7327de209 100644 --- a/src/include/utils/timeout.h +++ b/src/include/utils/timeout.h @@ -93,5 +93,6 @@ extern bool get_timeout_active(TimeoutId id); extern bool get_timeout_indicator(TimeoutId id, bool reset_indicator); extern TimestampTz get_timeout_start_time(TimeoutId id); extern TimestampTz get_timeout_finish_time(TimeoutId id); +extern bool get_all_timeouts_initialized(void); #endif /* TIMEOUT_H */ diff --git a/src/test/modules/test_custom_stats/t/001_custom_stats.pl b/src/test/modules/test_custom_stats/t/001_custom_stats.pl index 7be1b281776..22e2a75dcb9 100644 --- a/src/test/modules/test_custom_stats/t/001_custom_stats.pl +++ b/src/test/modules/test_custom_stats/t/001_custom_stats.pl @@ -164,10 +164,11 @@ $node->safe_psql('postgres', q(select test_custom_stats_fixed_reset())); $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); my $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; -- Accumulate stats select test_custom_stats_fixed_anytime_update() from generate_series(1, 2); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select 'anytime:'||numcalls from test_custom_stats_fixed_report(); @@ -183,11 +184,12 @@ like($result, qr/^anytime:2/m, $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; -- Accumulate stats select test_custom_stats_var_anytime_update('entry2'); select test_custom_stats_var_anytime_update('entry2'); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select * from test_custom_stats_var_report('entry2'); -- 2.34.1 --NVvBxFuyV/R+1/8/ Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="v10-0004-Remove-useless-calls-to-flush-some-stats.patch" ^ permalink raw reply [nested|flat] 15+ messages in thread
* [PATCH v11 3/5] Add GUC to specify non-transactional statistics flush interval @ 2026-01-28 07:53 Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 0 siblings, 0 replies; 15+ messages in thread From: Bertrand Drouvot @ 2026-01-28 07:53 UTC (permalink / raw) Adding pgstat_flush_interval, a new GUC to set the interval between flushes of non-transactional statistics. --- doc/src/sgml/config.sgml | 32 +++++++++++++++++++ src/backend/utils/activity/pgstat.c | 13 ++++++++ src/backend/utils/misc/guc_parameters.dat | 10 ++++++ src/backend/utils/misc/postgresql.conf.sample | 1 + src/backend/utils/misc/timeout.c | 6 ++++ src/include/pgstat.h | 6 ++-- src/include/utils/guc_hooks.h | 1 + src/include/utils/timeout.h | 1 + .../test_custom_stats/t/001_custom_stats.pl | 6 ++-- 9 files changed, 70 insertions(+), 6 deletions(-) 51.0% doc/src/sgml/ 10.6% src/backend/utils/activity/ 15.9% src/backend/utils/misc/ 3.6% src/include/utils/ 9.0% src/include/ 9.6% src/test/modules/test_custom_stats/t/ diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 20dbcaeb3ee..1eed71007a7 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -8929,6 +8929,38 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; </listitem> </varlistentry> + <varlistentry id="guc-stats-flush-interval" xreflabel="stats_flush_interval"> + <term><varname>stats_flush_interval</varname> (<type>integer</type>) + <indexterm> + <primary><varname>stats_flush_interval</varname> configuration parameter</primary> + </indexterm> + </term> + <listitem> + <para> + Sets the interval at which certain statistics, which can be updated while a + transaction is in progress, are made visible. These include WAL activity + and I/O operations. + Such statistics are refreshed at the specified interval and can be observed + during active transactions in monitoring views such as + <link linkend="monitoring-pg-stat-wal-view"><structname>pg_stat_wal</structname></link> + and + <link linkend="monitoring-pg-stat-io-view"><structname>pg_stat_io</structname></link>. + If the value is specified without a unit, milliseconds are assumed. + The default is 10 seconds (<literal>10s</literal>), which is generally + the smallest practical value for long-running transactions. + </para> + <note> + <para> + This parameter does not affect statistics that are only reported at + transaction end, such as the columns of <structname>pg_stat_all_tables</structname> + (for example, <structfield>n_tup_ins</structfield>, <structfield>n_tup_upd</structfield>, + and <structfield>n_tup_del</structfield>). These statistics are always + flushed at the end of a transaction. + </para> + </note> + </listitem> + </varlistentry> + </variablelist> </sect2> diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index ddd331e2c81..fd6ab0db16f 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -124,6 +124,8 @@ * ---------- */ +/* minimum interval non-forced stats flushes.*/ +#define PGSTAT_MIN_INTERVAL 1000 /* how long until to block flushing pending stats updates */ #define PGSTAT_MAX_INTERVAL 60000 /* when to call pgstat_report_stat() again, even when idle */ @@ -204,6 +206,7 @@ static inline bool pgstat_is_kind_valid(PgStat_Kind kind); bool pgstat_track_counts = false; int pgstat_fetch_consistency = PGSTAT_FETCH_CONSISTENCY_CACHE; +int pgstat_flush_interval = 10000; /* ---------- @@ -2171,6 +2174,16 @@ assign_stats_fetch_consistency(int newval, void *extra) force_stats_snapshot_clear = true; } +/* + * GUC assign_hook for stats_flush_interval. + */ +void +assign_stats_flush_interval(int newval, void *extra) +{ + if (get_all_timeouts_initialized()) + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, newval); +} + /* * Flushes only FLUSH_ANYTIME stats using non-blocking locks. Transactional * stats (FLUSH_AT_TXN_BOUNDARY) remain pending until transaction boundary. diff --git a/src/backend/utils/misc/guc_parameters.dat b/src/backend/utils/misc/guc_parameters.dat index 9507778415d..073e08c7892 100644 --- a/src/backend/utils/misc/guc_parameters.dat +++ b/src/backend/utils/misc/guc_parameters.dat @@ -2801,6 +2801,16 @@ assign_hook => 'assign_stats_fetch_consistency', }, +{ name => 'stats_flush_interval', type => 'int', context => 'PGC_USERSET', group => 'STATS_CUMULATIVE', + short_desc => 'Sets the interval between flushes of non-transactional statistics.', + flags => 'GUC_UNIT_MS', + variable => 'pgstat_flush_interval', + boot_val => '10000', + min => '1000', + max => 'INT_MAX', + assign_hook => 'assign_stats_flush_interval' +}, + { name => 'subtransaction_buffers', type => 'int', context => 'PGC_POSTMASTER', group => 'RESOURCES_MEM', short_desc => 'Sets the size of the dedicated buffer pool used for the subtransaction cache.', long_desc => '0 means use a fraction of "shared_buffers".', diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index f938cc65a3a..8bd37a25b38 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -688,6 +688,7 @@ #track_wal_io_timing = off #track_functions = none # none, pl, all #stats_fetch_consistency = cache # cache, none, snapshot +#stats_flush_interval = 10s # in milliseconds # - Monitoring - diff --git a/src/backend/utils/misc/timeout.c b/src/backend/utils/misc/timeout.c index ddba5dc607c..85c4260d1db 100644 --- a/src/backend/utils/misc/timeout.c +++ b/src/backend/utils/misc/timeout.c @@ -828,3 +828,9 @@ get_timeout_finish_time(TimeoutId id) { return all_timeouts[id].fin_time; } + +bool +get_all_timeouts_initialized(void) +{ + return all_timeouts_initialized; +} diff --git a/src/include/pgstat.h b/src/include/pgstat.h index b011a315679..90237c70829 100644 --- a/src/include/pgstat.h +++ b/src/include/pgstat.h @@ -34,9 +34,6 @@ /* Default directory to store temporary statistics data in */ #define PG_STAT_TMP_DIR "pg_stat_tmp" -/* Minimum interval non-forced stats flushes */ -#define PGSTAT_MIN_INTERVAL 1000 - /* Values for track_functions GUC variable --- order is significant! */ typedef enum TrackFunctionsLevel { @@ -548,7 +545,7 @@ extern void pgstat_force_next_flush(void); do { \ if (IsUnderPostmaster && !pgstat_pending_anytime) \ { \ - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); \ + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); \ pgstat_pending_anytime = true; \ } \ } while (0) @@ -831,6 +828,7 @@ extern PGDLLIMPORT bool pgstat_pending_anytime; extern PGDLLIMPORT bool pgstat_track_counts; extern PGDLLIMPORT int pgstat_track_functions; extern PGDLLIMPORT int pgstat_fetch_consistency; +extern PGDLLIMPORT int pgstat_flush_interval; /* diff --git a/src/include/utils/guc_hooks.h b/src/include/utils/guc_hooks.h index 9c90670d9b8..9b5d2a90387 100644 --- a/src/include/utils/guc_hooks.h +++ b/src/include/utils/guc_hooks.h @@ -132,6 +132,7 @@ extern bool check_session_authorization(char **newval, void **extra, GucSource s extern void assign_session_authorization(const char *newval, void *extra); extern void assign_session_replication_role(int newval, void *extra); extern void assign_stats_fetch_consistency(int newval, void *extra); +extern void assign_stats_flush_interval(int newval, void *extra); extern bool check_ssl(bool *newval, void **extra, GucSource source); extern bool check_stage_log_stats(bool *newval, void **extra, GucSource source); extern bool check_standard_conforming_strings(bool *newval, void **extra, diff --git a/src/include/utils/timeout.h b/src/include/utils/timeout.h index 10723bb664c..fe7327de209 100644 --- a/src/include/utils/timeout.h +++ b/src/include/utils/timeout.h @@ -93,5 +93,6 @@ extern bool get_timeout_active(TimeoutId id); extern bool get_timeout_indicator(TimeoutId id, bool reset_indicator); extern TimestampTz get_timeout_start_time(TimeoutId id); extern TimestampTz get_timeout_finish_time(TimeoutId id); +extern bool get_all_timeouts_initialized(void); #endif /* TIMEOUT_H */ diff --git a/src/test/modules/test_custom_stats/t/001_custom_stats.pl b/src/test/modules/test_custom_stats/t/001_custom_stats.pl index 6ba4022418f..920443487c0 100644 --- a/src/test/modules/test_custom_stats/t/001_custom_stats.pl +++ b/src/test/modules/test_custom_stats/t/001_custom_stats.pl @@ -164,11 +164,12 @@ $node->safe_psql('postgres', q(select test_custom_stats_fixed_reset())); $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); my $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; SET LOCAL stats_fetch_consistency = none; -- Accumulate stats select test_custom_stats_fixed_anytime_update() from generate_series(1, 2); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select 'fixed_anytime:'||numcalls from test_custom_stats_fixed_report(); @@ -184,12 +185,13 @@ like($result, qr/^fixed_anytime:2/m, $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; SET LOCAL stats_fetch_consistency = none; -- Accumulate stats select test_custom_stats_var_anytime_update('entry2'); select test_custom_stats_var_anytime_update('entry2'); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select 'var_anytime:'||calls from test_custom_stats_var_report('entry2'); -- 2.34.1 --2MEBAGW8+kohXisi Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="v11-0004-Remove-useless-calls-to-flush-some-stats.patch" ^ permalink raw reply [nested|flat] 15+ messages in thread
* [PATCH v9 3/5] Add GUC to specify non-transactional statistics flush interval @ 2026-01-28 07:53 Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 0 siblings, 0 replies; 15+ messages in thread From: Bertrand Drouvot @ 2026-01-28 07:53 UTC (permalink / raw) Adding pgstat_flush_interval, a new GUC to set the interval between flushes of non-transactional statistics. --- doc/src/sgml/config.sgml | 32 +++++++++++++++++++ src/backend/utils/activity/pgstat.c | 13 ++++++++ src/backend/utils/misc/guc_parameters.dat | 10 ++++++ src/backend/utils/misc/postgresql.conf.sample | 1 + src/backend/utils/misc/timeout.c | 6 ++++ src/include/pgstat.h | 6 ++-- src/include/utils/guc_hooks.h | 1 + src/include/utils/timeout.h | 1 + .../test_custom_stats/t/001_custom_stats.pl | 6 ++-- 9 files changed, 70 insertions(+), 6 deletions(-) 51.0% doc/src/sgml/ 10.6% src/backend/utils/activity/ 15.9% src/backend/utils/misc/ 3.6% src/include/utils/ 9.0% src/include/ 9.6% src/test/modules/test_custom_stats/t/ diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index faf0bdb62aa..03875b490b7 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -8932,6 +8932,38 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; </listitem> </varlistentry> + <varlistentry id="guc-stats-flush-interval" xreflabel="stats_flush_interval"> + <term><varname>stats_flush_interval</varname> (<type>integer</type>) + <indexterm> + <primary><varname>stats_flush_interval</varname> configuration parameter</primary> + </indexterm> + </term> + <listitem> + <para> + Sets the interval at which certain statistics, which can be updated while a + transaction is in progress, are made visible. These include WAL activity + and I/O operations. + Such statistics are refreshed at the specified interval and can be observed + during active transactions in monitoring views such as + <link linkend="monitoring-pg-stat-wal-view"><structname>pg_stat_wal</structname></link> + and + <link linkend="monitoring-pg-stat-io-view"><structname>pg_stat_io</structname></link>. + If the value is specified without a unit, milliseconds are assumed. + The default is 10 seconds (<literal>10s</literal>), which is generally + the smallest practical value for long-running transactions. + </para> + <note> + <para> + This parameter does not affect statistics that are only reported at + transaction end, such as the columns of <structname>pg_stat_all_tables</structname> + (for example, <structfield>n_tup_ins</structfield>, <structfield>n_tup_upd</structfield>, + and <structfield>n_tup_del</structfield>). These statistics are always + flushed at the end of a transaction. + </para> + </note> + </listitem> + </varlistentry> + </variablelist> </sect2> diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index 419dc512d9b..578c575dbfb 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -123,6 +123,8 @@ * ---------- */ +/* minimum interval non-forced stats flushes.*/ +#define PGSTAT_MIN_INTERVAL 1000 /* how long until to block flushing pending stats updates */ #define PGSTAT_MAX_INTERVAL 60000 /* when to call pgstat_report_stat() again, even when idle */ @@ -203,6 +205,7 @@ static inline bool pgstat_is_kind_valid(PgStat_Kind kind); bool pgstat_track_counts = false; int pgstat_fetch_consistency = PGSTAT_FETCH_CONSISTENCY_CACHE; +int pgstat_flush_interval = 10000; /* ---------- @@ -2170,6 +2173,16 @@ assign_stats_fetch_consistency(int newval, void *extra) force_stats_snapshot_clear = true; } +/* + * GUC assign_hook for stats_flush_interval. + */ +void +assign_stats_flush_interval(int newval, void *extra) +{ + if (get_all_timeouts_initialized()) + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, newval); +} + /* * Flushes only FLUSH_ANYTIME stats using non-blocking locks. Transactional * stats (FLUSH_AT_TXN_BOUNDARY) remain pending until transaction boundary. diff --git a/src/backend/utils/misc/guc_parameters.dat b/src/backend/utils/misc/guc_parameters.dat index 271c033952e..d2734caafea 100644 --- a/src/backend/utils/misc/guc_parameters.dat +++ b/src/backend/utils/misc/guc_parameters.dat @@ -2801,6 +2801,16 @@ assign_hook => 'assign_stats_fetch_consistency', }, +{ name => 'stats_flush_interval', type => 'int', context => 'PGC_USERSET', group => 'STATS_CUMULATIVE', + short_desc => 'Sets the interval between flushes of non-transactional statistics.', + flags => 'GUC_UNIT_MS', + variable => 'pgstat_flush_interval', + boot_val => '10000', + min => '1000', + max => 'INT_MAX', + assign_hook => 'assign_stats_flush_interval' +}, + { name => 'subtransaction_buffers', type => 'int', context => 'PGC_POSTMASTER', group => 'RESOURCES_MEM', short_desc => 'Sets the size of the dedicated buffer pool used for the subtransaction cache.', long_desc => '0 means use a fraction of "shared_buffers".', diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index f938cc65a3a..8bd37a25b38 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -688,6 +688,7 @@ #track_wal_io_timing = off #track_functions = none # none, pl, all #stats_fetch_consistency = cache # cache, none, snapshot +#stats_flush_interval = 10s # in milliseconds # - Monitoring - diff --git a/src/backend/utils/misc/timeout.c b/src/backend/utils/misc/timeout.c index ddba5dc607c..85c4260d1db 100644 --- a/src/backend/utils/misc/timeout.c +++ b/src/backend/utils/misc/timeout.c @@ -828,3 +828,9 @@ get_timeout_finish_time(TimeoutId id) { return all_timeouts[id].fin_time; } + +bool +get_all_timeouts_initialized(void) +{ + return all_timeouts_initialized; +} diff --git a/src/include/pgstat.h b/src/include/pgstat.h index f0f546d419a..7829c563316 100644 --- a/src/include/pgstat.h +++ b/src/include/pgstat.h @@ -35,9 +35,6 @@ /* Default directory to store temporary statistics data in */ #define PG_STAT_TMP_DIR "pg_stat_tmp" -/* Minimum interval non-forced stats flushes */ -#define PGSTAT_MIN_INTERVAL 1000 - /* Values for track_functions GUC variable --- order is significant! */ typedef enum TrackFunctionsLevel { @@ -549,7 +546,7 @@ extern void pgstat_force_next_flush(void); do { \ if (IsUnderPostmaster && !pgstat_pending_anytime) \ { \ - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); \ + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); \ pgstat_pending_anytime = true; \ } \ } while (0) @@ -833,6 +830,7 @@ extern PGDLLIMPORT bool pgstat_pending_anytime; extern PGDLLIMPORT bool pgstat_track_counts; extern PGDLLIMPORT int pgstat_track_functions; extern PGDLLIMPORT int pgstat_fetch_consistency; +extern PGDLLIMPORT int pgstat_flush_interval; /* diff --git a/src/include/utils/guc_hooks.h b/src/include/utils/guc_hooks.h index 9c90670d9b8..9b5d2a90387 100644 --- a/src/include/utils/guc_hooks.h +++ b/src/include/utils/guc_hooks.h @@ -132,6 +132,7 @@ extern bool check_session_authorization(char **newval, void **extra, GucSource s extern void assign_session_authorization(const char *newval, void *extra); extern void assign_session_replication_role(int newval, void *extra); extern void assign_stats_fetch_consistency(int newval, void *extra); +extern void assign_stats_flush_interval(int newval, void *extra); extern bool check_ssl(bool *newval, void **extra, GucSource source); extern bool check_stage_log_stats(bool *newval, void **extra, GucSource source); extern bool check_standard_conforming_strings(bool *newval, void **extra, diff --git a/src/include/utils/timeout.h b/src/include/utils/timeout.h index 10723bb664c..fe7327de209 100644 --- a/src/include/utils/timeout.h +++ b/src/include/utils/timeout.h @@ -93,5 +93,6 @@ extern bool get_timeout_active(TimeoutId id); extern bool get_timeout_indicator(TimeoutId id, bool reset_indicator); extern TimestampTz get_timeout_start_time(TimeoutId id); extern TimestampTz get_timeout_finish_time(TimeoutId id); +extern bool get_all_timeouts_initialized(void); #endif /* TIMEOUT_H */ diff --git a/src/test/modules/test_custom_stats/t/001_custom_stats.pl b/src/test/modules/test_custom_stats/t/001_custom_stats.pl index 7be1b281776..22e2a75dcb9 100644 --- a/src/test/modules/test_custom_stats/t/001_custom_stats.pl +++ b/src/test/modules/test_custom_stats/t/001_custom_stats.pl @@ -164,10 +164,11 @@ $node->safe_psql('postgres', q(select test_custom_stats_fixed_reset())); $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); my $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; -- Accumulate stats select test_custom_stats_fixed_anytime_update() from generate_series(1, 2); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select 'anytime:'||numcalls from test_custom_stats_fixed_report(); @@ -183,11 +184,12 @@ like($result, qr/^anytime:2/m, $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; -- Accumulate stats select test_custom_stats_var_anytime_update('entry2'); select test_custom_stats_var_anytime_update('entry2'); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select * from test_custom_stats_var_report('entry2'); -- 2.34.1 --aq/6bi8L6WORnI+9 Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="v9-0004-Remove-useless-calls-to-flush-some-stats.patch" ^ permalink raw reply [nested|flat] 15+ messages in thread
* [PATCH v8 3/5] Add GUC to specify non-transactional statistics flush interval @ 2026-01-28 07:53 Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 0 siblings, 0 replies; 15+ messages in thread From: Bertrand Drouvot @ 2026-01-28 07:53 UTC (permalink / raw) Adding pgstat_flush_interval, a new GUC to set the interval between flushes of non-transactional statistics. --- doc/src/sgml/config.sgml | 32 +++++++++++++++++++ src/backend/utils/activity/pgstat.c | 16 ++++++++++ src/backend/utils/misc/guc_parameters.dat | 10 ++++++ src/backend/utils/misc/postgresql.conf.sample | 1 + src/include/pgstat.h | 6 ++-- src/include/utils/guc_hooks.h | 1 + .../test_custom_stats/t/001_custom_stats.pl | 6 ++-- 7 files changed, 66 insertions(+), 6 deletions(-) 51.8% doc/src/sgml/ 13.3% src/backend/utils/activity/ 13.6% src/backend/utils/misc/ 11.3% src/include/ 9.8% src/test/modules/test_custom_stats/t/ diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index faf0bdb62aa..03875b490b7 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -8932,6 +8932,38 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; </listitem> </varlistentry> + <varlistentry id="guc-stats-flush-interval" xreflabel="stats_flush_interval"> + <term><varname>stats_flush_interval</varname> (<type>integer</type>) + <indexterm> + <primary><varname>stats_flush_interval</varname> configuration parameter</primary> + </indexterm> + </term> + <listitem> + <para> + Sets the interval at which certain statistics, which can be updated while a + transaction is in progress, are made visible. These include WAL activity + and I/O operations. + Such statistics are refreshed at the specified interval and can be observed + during active transactions in monitoring views such as + <link linkend="monitoring-pg-stat-wal-view"><structname>pg_stat_wal</structname></link> + and + <link linkend="monitoring-pg-stat-io-view"><structname>pg_stat_io</structname></link>. + If the value is specified without a unit, milliseconds are assumed. + The default is 10 seconds (<literal>10s</literal>), which is generally + the smallest practical value for long-running transactions. + </para> + <note> + <para> + This parameter does not affect statistics that are only reported at + transaction end, such as the columns of <structname>pg_stat_all_tables</structname> + (for example, <structfield>n_tup_ins</structfield>, <structfield>n_tup_upd</structfield>, + and <structfield>n_tup_del</structfield>). These statistics are always + flushed at the end of a transaction. + </para> + </note> + </listitem> + </varlistentry> + </variablelist> </sect2> diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index a4ff64dc5ce..dd85a27c52f 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -123,6 +123,8 @@ * ---------- */ +/* minimum interval non-forced stats flushes.*/ +#define PGSTAT_MIN_INTERVAL 1000 /* how long until to block flushing pending stats updates */ #define PGSTAT_MAX_INTERVAL 60000 /* when to call pgstat_report_stat() again, even when idle */ @@ -203,6 +205,7 @@ static inline bool pgstat_is_kind_valid(PgStat_Kind kind); bool pgstat_track_counts = false; int pgstat_fetch_consistency = PGSTAT_FETCH_CONSISTENCY_CACHE; +int pgstat_flush_interval = 10000; /* ---------- @@ -2164,6 +2167,19 @@ assign_stats_fetch_consistency(int newval, void *extra) force_stats_snapshot_clear = true; } +/* + * GUC assign_hook for stats_flush_interval. + */ +void +assign_stats_flush_interval(int newval, void *extra) +{ + if (get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) + { + disable_timeout(ANYTIME_STATS_UPDATE_TIMEOUT, false); + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, newval); + } +} + /* * Flushes only FLUSH_ANYTIME stats using non-blocking locks. Transactional * stats (FLUSH_AT_TXN_BOUNDARY) remain pending until transaction boundary. diff --git a/src/backend/utils/misc/guc_parameters.dat b/src/backend/utils/misc/guc_parameters.dat index 271c033952e..d2734caafea 100644 --- a/src/backend/utils/misc/guc_parameters.dat +++ b/src/backend/utils/misc/guc_parameters.dat @@ -2801,6 +2801,16 @@ assign_hook => 'assign_stats_fetch_consistency', }, +{ name => 'stats_flush_interval', type => 'int', context => 'PGC_USERSET', group => 'STATS_CUMULATIVE', + short_desc => 'Sets the interval between flushes of non-transactional statistics.', + flags => 'GUC_UNIT_MS', + variable => 'pgstat_flush_interval', + boot_val => '10000', + min => '1000', + max => 'INT_MAX', + assign_hook => 'assign_stats_flush_interval' +}, + { name => 'subtransaction_buffers', type => 'int', context => 'PGC_POSTMASTER', group => 'RESOURCES_MEM', short_desc => 'Sets the size of the dedicated buffer pool used for the subtransaction cache.', long_desc => '0 means use a fraction of "shared_buffers".', diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index f938cc65a3a..8bd37a25b38 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -688,6 +688,7 @@ #track_wal_io_timing = off #track_functions = none # none, pl, all #stats_fetch_consistency = cache # cache, none, snapshot +#stats_flush_interval = 10s # in milliseconds # - Monitoring - diff --git a/src/include/pgstat.h b/src/include/pgstat.h index b340a680614..ef856dbf55b 100644 --- a/src/include/pgstat.h +++ b/src/include/pgstat.h @@ -35,9 +35,6 @@ /* Default directory to store temporary statistics data in */ #define PG_STAT_TMP_DIR "pg_stat_tmp" -/* Minimum interval non-forced stats flushes */ -#define PGSTAT_MIN_INTERVAL 1000 - /* Values for track_functions GUC variable --- order is significant! */ typedef enum TrackFunctionsLevel { @@ -548,7 +545,7 @@ extern void pgstat_force_next_flush(void); #define pgstat_schedule_anytime_update() \ do { \ if (IsUnderPostmaster && !get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) \ - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); \ + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); \ } while (0) extern void pgstat_reset_counters(void); @@ -828,6 +825,7 @@ extern PgStat_WalStats *pgstat_fetch_stat_wal(void); extern PGDLLIMPORT bool pgstat_track_counts; extern PGDLLIMPORT int pgstat_track_functions; extern PGDLLIMPORT int pgstat_fetch_consistency; +extern PGDLLIMPORT int pgstat_flush_interval; /* diff --git a/src/include/utils/guc_hooks.h b/src/include/utils/guc_hooks.h index 9c90670d9b8..9b5d2a90387 100644 --- a/src/include/utils/guc_hooks.h +++ b/src/include/utils/guc_hooks.h @@ -132,6 +132,7 @@ extern bool check_session_authorization(char **newval, void **extra, GucSource s extern void assign_session_authorization(const char *newval, void *extra); extern void assign_session_replication_role(int newval, void *extra); extern void assign_stats_fetch_consistency(int newval, void *extra); +extern void assign_stats_flush_interval(int newval, void *extra); extern bool check_ssl(bool *newval, void **extra, GucSource source); extern bool check_stage_log_stats(bool *newval, void **extra, GucSource source); extern bool check_standard_conforming_strings(bool *newval, void **extra, diff --git a/src/test/modules/test_custom_stats/t/001_custom_stats.pl b/src/test/modules/test_custom_stats/t/001_custom_stats.pl index 7be1b281776..22e2a75dcb9 100644 --- a/src/test/modules/test_custom_stats/t/001_custom_stats.pl +++ b/src/test/modules/test_custom_stats/t/001_custom_stats.pl @@ -164,10 +164,11 @@ $node->safe_psql('postgres', q(select test_custom_stats_fixed_reset())); $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); my $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; -- Accumulate stats select test_custom_stats_fixed_anytime_update() from generate_series(1, 2); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select 'anytime:'||numcalls from test_custom_stats_fixed_report(); @@ -183,11 +184,12 @@ like($result, qr/^anytime:2/m, $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; -- Accumulate stats select test_custom_stats_var_anytime_update('entry2'); select test_custom_stats_var_anytime_update('entry2'); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select * from test_custom_stats_var_report('entry2'); -- 2.34.1 --OI5irqZsxWxBW9nT Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="v8-0004-Remove-useless-calls-to-flush-some-stats.patch" ^ permalink raw reply [nested|flat] 15+ messages in thread
* [PATCH v5 2/4] Add GUC to specify non-transactional statistics flush interval @ 2026-01-28 07:53 Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 0 siblings, 0 replies; 15+ messages in thread From: Bertrand Drouvot @ 2026-01-28 07:53 UTC (permalink / raw) Adding pgstat_flush_interval, a new GUC to set the interval between flushes of non-transactional statistics. --- doc/src/sgml/config.sgml | 32 +++++++++++++++++++ src/backend/access/transam/xlog.c | 4 +-- src/backend/utils/activity/pgstat.c | 16 +++++++++- src/backend/utils/activity/pgstat_backend.c | 4 +-- src/backend/utils/activity/pgstat_io.c | 2 +- src/backend/utils/activity/pgstat_slru.c | 2 +- src/backend/utils/misc/guc_parameters.dat | 10 ++++++ src/backend/utils/misc/postgresql.conf.sample | 1 + src/include/pgstat.h | 1 + src/include/utils/guc_hooks.h | 1 + 10 files changed, 66 insertions(+), 7 deletions(-) 45.9% doc/src/sgml/ 6.5% src/backend/access/transam/ 31.8% src/backend/utils/activity/ 12.3% src/backend/utils/misc/ 3.2% src/include/ diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 5560b95ee60..3136816a933 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -8834,6 +8834,38 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; </listitem> </varlistentry> + <varlistentry id="guc-stats-flush-interval" xreflabel="stats_flush_interval"> + <term><varname>stats_flush_interval</varname> (<type>integer</type>) + <indexterm> + <primary><varname>stats_flush_interval</varname> configuration parameter</primary> + </indexterm> + </term> + <listitem> + <para> + Sets the interval at which non-transactional statistics are made visible + during running transactions. Non-transactional statistics include, for + example, WAL activity and I/O operations. + They become visible at that interval in monitoring views such as + <link linkend="monitoring-pg-stat-io-view"> <structname>pg_stat_io</structname></link> + and <link linkend="monitoring-pg-stat-wal-view"> <structname>pg_stat_wal</structname></link> + during running transactions. + If this value is specified without units, it is taken as milliseconds. + The default is 10 seconds (<literal>10s</literal>), which is probably + about the smallest value you would want in practice for long running + transactions. + </para> + <note> + <para> + This parameter does not affect transactional statistics such as + <structname>pg_stat_all_tables</structname> columns (like + <structfield>n_tup_ins</structfield>, <structfield>n_tup_upd</structfield>, + <structfield>n_tup_del</structfield>), which are always flushed at transaction + boundaries to maintain consistency. + </para> + </note> + </listitem> + </varlistentry> + </variablelist> </sect2> diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index 9503aea5b4d..31523dea923 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -1087,7 +1087,7 @@ XLogInsertRecord(XLogRecData *rdata, /* Schedule next anytime stats update timeout */ if (IsUnderPostmaster && !get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); /* Required for the flush of pending stats WAL data */ pgstat_report_fixed = true; @@ -2073,7 +2073,7 @@ AdvanceXLInsertBuffer(XLogRecPtr upto, TimeLineID tli, bool opportunistic) /* Schedule next anytime stats update timeout */ if (IsUnderPostmaster && !get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, - PGSTAT_MIN_INTERVAL); + pgstat_flush_interval); /* * Required for the flush of pending stats WAL data, per diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index 2c9454677e9..dd174129403 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -203,6 +203,7 @@ static inline bool pgstat_is_kind_valid(PgStat_Kind kind); bool pgstat_track_counts = false; int pgstat_fetch_consistency = PGSTAT_FETCH_CONSISTENCY_CACHE; +int pgstat_flush_interval = 10000; /* ---------- @@ -1304,7 +1305,7 @@ pgstat_prep_pending_entry(PgStat_Kind kind, Oid dboid, uint64 objid, bool *creat /* Schedule next anytime stats update timeout */ if (kind_info->flush_mode == FLUSH_ANYTIME && IsUnderPostmaster && !get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); } return entry_ref; @@ -2172,6 +2173,19 @@ assign_stats_fetch_consistency(int newval, void *extra) force_stats_snapshot_clear = true; } +/* + * GUC assign_hook for stats_flush_interval. + */ +void +assign_stats_flush_interval(int newval, void *extra) +{ + if (get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) + { + disable_timeout(ANYTIME_STATS_UPDATE_TIMEOUT, false); + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, newval); + } +} + /* * Flushes only FLUSH_ANYTIME stats using non-blocking locks. Transactional * stats (FLUSH_AT_TXN_BOUNDARY) remain pending until transaction boundary. diff --git a/src/backend/utils/activity/pgstat_backend.c b/src/backend/utils/activity/pgstat_backend.c index 9dcb24db975..f5b8c7b039c 100644 --- a/src/backend/utils/activity/pgstat_backend.c +++ b/src/backend/utils/activity/pgstat_backend.c @@ -69,7 +69,7 @@ pgstat_count_backend_io_op_time(IOObject io_object, IOContext io_context, /* Schedule next anytime stats update timeout */ if (IsUnderPostmaster && !get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); backend_has_iostats = true; pgstat_report_fixed = true; @@ -89,7 +89,7 @@ pgstat_count_backend_io_op(IOObject io_object, IOContext io_context, /* Schedule next anytime stats update timeout */ if (IsUnderPostmaster && !get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); backend_has_iostats = true; pgstat_report_fixed = true; diff --git a/src/backend/utils/activity/pgstat_io.c b/src/backend/utils/activity/pgstat_io.c index 53dbf2a514b..b69a1e26f7d 100644 --- a/src/backend/utils/activity/pgstat_io.c +++ b/src/backend/utils/activity/pgstat_io.c @@ -82,7 +82,7 @@ pgstat_count_io_op(IOObject io_object, IOContext io_context, IOOp io_op, /* Schedule next anytime stats update timeout */ if (IsUnderPostmaster && !get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); have_iostats = true; pgstat_report_fixed = true; diff --git a/src/backend/utils/activity/pgstat_slru.c b/src/backend/utils/activity/pgstat_slru.c index 1d16cde1889..36231ee874b 100644 --- a/src/backend/utils/activity/pgstat_slru.c +++ b/src/backend/utils/activity/pgstat_slru.c @@ -226,7 +226,7 @@ get_slru_entry(int slru_idx) /* Schedule next anytime stats update timeout */ if (IsUnderPostmaster && !get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); have_slrustats = true; pgstat_report_fixed = true; diff --git a/src/backend/utils/misc/guc_parameters.dat b/src/backend/utils/misc/guc_parameters.dat index f0260e6e412..3bb43362e51 100644 --- a/src/backend/utils/misc/guc_parameters.dat +++ b/src/backend/utils/misc/guc_parameters.dat @@ -2782,6 +2782,16 @@ assign_hook => 'assign_stats_fetch_consistency', }, +{ name => 'stats_flush_interval', type => 'int', context => 'PGC_USERSET', group => 'STATS_CUMULATIVE', + short_desc => 'Sets the interval between flushes of non-transactional statistics.', + flags => 'GUC_UNIT_MS', + variable => 'pgstat_flush_interval', + boot_val => '10000', + min => '1000', + max => 'INT_MAX', + assign_hook => 'assign_stats_flush_interval' +}, + { name => 'subtransaction_buffers', type => 'int', context => 'PGC_POSTMASTER', group => 'RESOURCES_MEM', short_desc => 'Sets the size of the dedicated buffer pool used for the subtransaction cache.', long_desc => '0 means use a fraction of "shared_buffers".', diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index c4f92fcdac8..6ce5a250170 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -669,6 +669,7 @@ #track_wal_io_timing = off #track_functions = none # none, pl, all #stats_fetch_consistency = cache # cache, none, snapshot +#stats_flush_interval = 10s # in milliseconds # - Monitoring - diff --git a/src/include/pgstat.h b/src/include/pgstat.h index 1651f16f966..e0f222695bf 100644 --- a/src/include/pgstat.h +++ b/src/include/pgstat.h @@ -816,6 +816,7 @@ extern PgStat_WalStats *pgstat_fetch_stat_wal(void); extern PGDLLIMPORT bool pgstat_track_counts; extern PGDLLIMPORT int pgstat_track_functions; extern PGDLLIMPORT int pgstat_fetch_consistency; +extern PGDLLIMPORT int pgstat_flush_interval; /* diff --git a/src/include/utils/guc_hooks.h b/src/include/utils/guc_hooks.h index b6ecb0e769f..3a2ae6c41cd 100644 --- a/src/include/utils/guc_hooks.h +++ b/src/include/utils/guc_hooks.h @@ -132,6 +132,7 @@ extern bool check_session_authorization(char **newval, void **extra, GucSource s extern void assign_session_authorization(const char *newval, void *extra); extern void assign_session_replication_role(int newval, void *extra); extern void assign_stats_fetch_consistency(int newval, void *extra); +extern void assign_stats_flush_interval(int newval, void *extra); extern bool check_ssl(bool *newval, void **extra, GucSource source); extern bool check_stage_log_stats(bool *newval, void **extra, GucSource source); extern bool check_standard_conforming_strings(bool *newval, void **extra, -- 2.34.1 --WLtTrIUEfQDmERxy Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="v5-0003-Remove-useless-calls-to-flush-some-stats.patch" ^ permalink raw reply [nested|flat] 15+ messages in thread
* [PATCH v10 3/5] Add GUC to specify non-transactional statistics flush interval @ 2026-01-28 07:53 Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 0 siblings, 0 replies; 15+ messages in thread From: Bertrand Drouvot @ 2026-01-28 07:53 UTC (permalink / raw) Adding pgstat_flush_interval, a new GUC to set the interval between flushes of non-transactional statistics. --- doc/src/sgml/config.sgml | 32 +++++++++++++++++++ src/backend/utils/activity/pgstat.c | 13 ++++++++ src/backend/utils/misc/guc_parameters.dat | 10 ++++++ src/backend/utils/misc/postgresql.conf.sample | 1 + src/backend/utils/misc/timeout.c | 6 ++++ src/include/pgstat.h | 6 ++-- src/include/utils/guc_hooks.h | 1 + src/include/utils/timeout.h | 1 + .../test_custom_stats/t/001_custom_stats.pl | 6 ++-- 9 files changed, 70 insertions(+), 6 deletions(-) 51.0% doc/src/sgml/ 10.6% src/backend/utils/activity/ 15.9% src/backend/utils/misc/ 3.6% src/include/utils/ 9.0% src/include/ 9.6% src/test/modules/test_custom_stats/t/ diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 20dbcaeb3ee..1eed71007a7 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -8929,6 +8929,38 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; </listitem> </varlistentry> + <varlistentry id="guc-stats-flush-interval" xreflabel="stats_flush_interval"> + <term><varname>stats_flush_interval</varname> (<type>integer</type>) + <indexterm> + <primary><varname>stats_flush_interval</varname> configuration parameter</primary> + </indexterm> + </term> + <listitem> + <para> + Sets the interval at which certain statistics, which can be updated while a + transaction is in progress, are made visible. These include WAL activity + and I/O operations. + Such statistics are refreshed at the specified interval and can be observed + during active transactions in monitoring views such as + <link linkend="monitoring-pg-stat-wal-view"><structname>pg_stat_wal</structname></link> + and + <link linkend="monitoring-pg-stat-io-view"><structname>pg_stat_io</structname></link>. + If the value is specified without a unit, milliseconds are assumed. + The default is 10 seconds (<literal>10s</literal>), which is generally + the smallest practical value for long-running transactions. + </para> + <note> + <para> + This parameter does not affect statistics that are only reported at + transaction end, such as the columns of <structname>pg_stat_all_tables</structname> + (for example, <structfield>n_tup_ins</structfield>, <structfield>n_tup_upd</structfield>, + and <structfield>n_tup_del</structfield>). These statistics are always + flushed at the end of a transaction. + </para> + </note> + </listitem> + </varlistentry> + </variablelist> </sect2> diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index ddd331e2c81..fd6ab0db16f 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -124,6 +124,8 @@ * ---------- */ +/* minimum interval non-forced stats flushes.*/ +#define PGSTAT_MIN_INTERVAL 1000 /* how long until to block flushing pending stats updates */ #define PGSTAT_MAX_INTERVAL 60000 /* when to call pgstat_report_stat() again, even when idle */ @@ -204,6 +206,7 @@ static inline bool pgstat_is_kind_valid(PgStat_Kind kind); bool pgstat_track_counts = false; int pgstat_fetch_consistency = PGSTAT_FETCH_CONSISTENCY_CACHE; +int pgstat_flush_interval = 10000; /* ---------- @@ -2171,6 +2174,16 @@ assign_stats_fetch_consistency(int newval, void *extra) force_stats_snapshot_clear = true; } +/* + * GUC assign_hook for stats_flush_interval. + */ +void +assign_stats_flush_interval(int newval, void *extra) +{ + if (get_all_timeouts_initialized()) + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, newval); +} + /* * Flushes only FLUSH_ANYTIME stats using non-blocking locks. Transactional * stats (FLUSH_AT_TXN_BOUNDARY) remain pending until transaction boundary. diff --git a/src/backend/utils/misc/guc_parameters.dat b/src/backend/utils/misc/guc_parameters.dat index 9507778415d..073e08c7892 100644 --- a/src/backend/utils/misc/guc_parameters.dat +++ b/src/backend/utils/misc/guc_parameters.dat @@ -2801,6 +2801,16 @@ assign_hook => 'assign_stats_fetch_consistency', }, +{ name => 'stats_flush_interval', type => 'int', context => 'PGC_USERSET', group => 'STATS_CUMULATIVE', + short_desc => 'Sets the interval between flushes of non-transactional statistics.', + flags => 'GUC_UNIT_MS', + variable => 'pgstat_flush_interval', + boot_val => '10000', + min => '1000', + max => 'INT_MAX', + assign_hook => 'assign_stats_flush_interval' +}, + { name => 'subtransaction_buffers', type => 'int', context => 'PGC_POSTMASTER', group => 'RESOURCES_MEM', short_desc => 'Sets the size of the dedicated buffer pool used for the subtransaction cache.', long_desc => '0 means use a fraction of "shared_buffers".', diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index f938cc65a3a..8bd37a25b38 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -688,6 +688,7 @@ #track_wal_io_timing = off #track_functions = none # none, pl, all #stats_fetch_consistency = cache # cache, none, snapshot +#stats_flush_interval = 10s # in milliseconds # - Monitoring - diff --git a/src/backend/utils/misc/timeout.c b/src/backend/utils/misc/timeout.c index ddba5dc607c..85c4260d1db 100644 --- a/src/backend/utils/misc/timeout.c +++ b/src/backend/utils/misc/timeout.c @@ -828,3 +828,9 @@ get_timeout_finish_time(TimeoutId id) { return all_timeouts[id].fin_time; } + +bool +get_all_timeouts_initialized(void) +{ + return all_timeouts_initialized; +} diff --git a/src/include/pgstat.h b/src/include/pgstat.h index b011a315679..90237c70829 100644 --- a/src/include/pgstat.h +++ b/src/include/pgstat.h @@ -34,9 +34,6 @@ /* Default directory to store temporary statistics data in */ #define PG_STAT_TMP_DIR "pg_stat_tmp" -/* Minimum interval non-forced stats flushes */ -#define PGSTAT_MIN_INTERVAL 1000 - /* Values for track_functions GUC variable --- order is significant! */ typedef enum TrackFunctionsLevel { @@ -548,7 +545,7 @@ extern void pgstat_force_next_flush(void); do { \ if (IsUnderPostmaster && !pgstat_pending_anytime) \ { \ - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); \ + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); \ pgstat_pending_anytime = true; \ } \ } while (0) @@ -831,6 +828,7 @@ extern PGDLLIMPORT bool pgstat_pending_anytime; extern PGDLLIMPORT bool pgstat_track_counts; extern PGDLLIMPORT int pgstat_track_functions; extern PGDLLIMPORT int pgstat_fetch_consistency; +extern PGDLLIMPORT int pgstat_flush_interval; /* diff --git a/src/include/utils/guc_hooks.h b/src/include/utils/guc_hooks.h index 9c90670d9b8..9b5d2a90387 100644 --- a/src/include/utils/guc_hooks.h +++ b/src/include/utils/guc_hooks.h @@ -132,6 +132,7 @@ extern bool check_session_authorization(char **newval, void **extra, GucSource s extern void assign_session_authorization(const char *newval, void *extra); extern void assign_session_replication_role(int newval, void *extra); extern void assign_stats_fetch_consistency(int newval, void *extra); +extern void assign_stats_flush_interval(int newval, void *extra); extern bool check_ssl(bool *newval, void **extra, GucSource source); extern bool check_stage_log_stats(bool *newval, void **extra, GucSource source); extern bool check_standard_conforming_strings(bool *newval, void **extra, diff --git a/src/include/utils/timeout.h b/src/include/utils/timeout.h index 10723bb664c..fe7327de209 100644 --- a/src/include/utils/timeout.h +++ b/src/include/utils/timeout.h @@ -93,5 +93,6 @@ extern bool get_timeout_active(TimeoutId id); extern bool get_timeout_indicator(TimeoutId id, bool reset_indicator); extern TimestampTz get_timeout_start_time(TimeoutId id); extern TimestampTz get_timeout_finish_time(TimeoutId id); +extern bool get_all_timeouts_initialized(void); #endif /* TIMEOUT_H */ diff --git a/src/test/modules/test_custom_stats/t/001_custom_stats.pl b/src/test/modules/test_custom_stats/t/001_custom_stats.pl index 7be1b281776..22e2a75dcb9 100644 --- a/src/test/modules/test_custom_stats/t/001_custom_stats.pl +++ b/src/test/modules/test_custom_stats/t/001_custom_stats.pl @@ -164,10 +164,11 @@ $node->safe_psql('postgres', q(select test_custom_stats_fixed_reset())); $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); my $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; -- Accumulate stats select test_custom_stats_fixed_anytime_update() from generate_series(1, 2); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select 'anytime:'||numcalls from test_custom_stats_fixed_report(); @@ -183,11 +184,12 @@ like($result, qr/^anytime:2/m, $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; -- Accumulate stats select test_custom_stats_var_anytime_update('entry2'); select test_custom_stats_var_anytime_update('entry2'); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select * from test_custom_stats_var_report('entry2'); -- 2.34.1 --NVvBxFuyV/R+1/8/ Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="v10-0004-Remove-useless-calls-to-flush-some-stats.patch" ^ permalink raw reply [nested|flat] 15+ messages in thread
* [PATCH v4 2/4] Add GUC to specify non-transactional statistics flush interval @ 2026-01-28 07:53 Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 0 siblings, 0 replies; 15+ messages in thread From: Bertrand Drouvot @ 2026-01-28 07:53 UTC (permalink / raw) Adding pgstat_flush_interval, a new GUC to set the interval between flushes of non-transactional statistics. --- doc/src/sgml/config.sgml | 32 +++++++++++++++++++ src/backend/storage/lmgr/proc.c | 2 +- src/backend/tcop/postgres.c | 2 +- src/backend/utils/activity/pgstat.c | 15 +++++++++ src/backend/utils/init/postinit.c | 2 +- src/backend/utils/misc/guc_parameters.dat | 10 ++++++ src/backend/utils/misc/postgresql.conf.sample | 1 + src/include/pgstat.h | 1 + src/include/utils/guc_hooks.h | 1 + 9 files changed, 63 insertions(+), 3 deletions(-) 55.5% doc/src/sgml/ 5.3% src/backend/storage/lmgr/ 12.6% src/backend/utils/activity/ 5.3% src/backend/utils/init/ 14.9% src/backend/utils/misc/ 3.9% src/include/ diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 5560b95ee60..3136816a933 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -8834,6 +8834,38 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; </listitem> </varlistentry> + <varlistentry id="guc-stats-flush-interval" xreflabel="stats_flush_interval"> + <term><varname>stats_flush_interval</varname> (<type>integer</type>) + <indexterm> + <primary><varname>stats_flush_interval</varname> configuration parameter</primary> + </indexterm> + </term> + <listitem> + <para> + Sets the interval at which non-transactional statistics are made visible + during running transactions. Non-transactional statistics include, for + example, WAL activity and I/O operations. + They become visible at that interval in monitoring views such as + <link linkend="monitoring-pg-stat-io-view"> <structname>pg_stat_io</structname></link> + and <link linkend="monitoring-pg-stat-wal-view"> <structname>pg_stat_wal</structname></link> + during running transactions. + If this value is specified without units, it is taken as milliseconds. + The default is 10 seconds (<literal>10s</literal>), which is probably + about the smallest value you would want in practice for long running + transactions. + </para> + <note> + <para> + This parameter does not affect transactional statistics such as + <structname>pg_stat_all_tables</structname> columns (like + <structfield>n_tup_ins</structfield>, <structfield>n_tup_upd</structfield>, + <structfield>n_tup_del</structfield>), which are always flushed at transaction + boundaries to maintain consistency. + </para> + </note> + </listitem> + </varlistentry> + </variablelist> </sect2> diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c index 012705a2ee6..caa6eecca88 100644 --- a/src/backend/storage/lmgr/proc.c +++ b/src/backend/storage/lmgr/proc.c @@ -1669,7 +1669,7 @@ ProcSleep(LOCALLOCK *locallock) } while (myWaitStatus == PROC_WAIT_STATUS_WAITING); if (anytime_timeout_was_active) - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); /* * Disable the timers, if they are still running. As in LockErrorCleanup, diff --git a/src/backend/tcop/postgres.c b/src/backend/tcop/postgres.c index 132fae61423..c0e81cb13d0 100644 --- a/src/backend/tcop/postgres.c +++ b/src/backend/tcop/postgres.c @@ -3543,7 +3543,7 @@ ProcessInterrupts(void) /* Schedule next timeout */ enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, - PGSTAT_MIN_INTERVAL); + pgstat_flush_interval); } if (ProcSignalBarrierPending) diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index ab4d9088a9a..ca08dd49cd7 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -113,6 +113,7 @@ #include "utils/memutils.h" #include "utils/pgstat_internal.h" #include "utils/timestamp.h" +#include "utils/timeout.h" /* ---------- @@ -202,6 +203,7 @@ static inline bool pgstat_is_kind_valid(PgStat_Kind kind); bool pgstat_track_counts = false; int pgstat_fetch_consistency = PGSTAT_FETCH_CONSISTENCY_CACHE; +int pgstat_flush_interval = 10000; /* ---------- @@ -2165,6 +2167,19 @@ assign_stats_fetch_consistency(int newval, void *extra) force_stats_snapshot_clear = true; } +/* + * GUC assign_hook for stats_flush_interval. + */ +void +assign_stats_flush_interval(int newval, void *extra) +{ + if (get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) + { + disable_timeout(ANYTIME_STATS_UPDATE_TIMEOUT, false); + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, newval); + } +} + /* * Flushes only FLUSH_ANYTIME stats using non-blocking locks. Transactional * stats (FLUSH_AT_TXN_BOUNDARY) remain pending until transaction boundary. diff --git a/src/backend/utils/init/postinit.c b/src/backend/utils/init/postinit.c index 6076f531c4a..c7c0d618671 100644 --- a/src/backend/utils/init/postinit.c +++ b/src/backend/utils/init/postinit.c @@ -768,7 +768,7 @@ InitPostgres(const char *in_dbname, Oid dboid, IdleStatsUpdateTimeoutHandler); RegisterTimeout(ANYTIME_STATS_UPDATE_TIMEOUT, AnytimeStatsUpdateTimeoutHandler); - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); } /* diff --git a/src/backend/utils/misc/guc_parameters.dat b/src/backend/utils/misc/guc_parameters.dat index f0260e6e412..3bb43362e51 100644 --- a/src/backend/utils/misc/guc_parameters.dat +++ b/src/backend/utils/misc/guc_parameters.dat @@ -2782,6 +2782,16 @@ assign_hook => 'assign_stats_fetch_consistency', }, +{ name => 'stats_flush_interval', type => 'int', context => 'PGC_USERSET', group => 'STATS_CUMULATIVE', + short_desc => 'Sets the interval between flushes of non-transactional statistics.', + flags => 'GUC_UNIT_MS', + variable => 'pgstat_flush_interval', + boot_val => '10000', + min => '1000', + max => 'INT_MAX', + assign_hook => 'assign_stats_flush_interval' +}, + { name => 'subtransaction_buffers', type => 'int', context => 'PGC_POSTMASTER', group => 'RESOURCES_MEM', short_desc => 'Sets the size of the dedicated buffer pool used for the subtransaction cache.', long_desc => '0 means use a fraction of "shared_buffers".', diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index c4f92fcdac8..6ce5a250170 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -669,6 +669,7 @@ #track_wal_io_timing = off #track_functions = none # none, pl, all #stats_fetch_consistency = cache # cache, none, snapshot +#stats_flush_interval = 10s # in milliseconds # - Monitoring - diff --git a/src/include/pgstat.h b/src/include/pgstat.h index 1651f16f966..e0f222695bf 100644 --- a/src/include/pgstat.h +++ b/src/include/pgstat.h @@ -816,6 +816,7 @@ extern PgStat_WalStats *pgstat_fetch_stat_wal(void); extern PGDLLIMPORT bool pgstat_track_counts; extern PGDLLIMPORT int pgstat_track_functions; extern PGDLLIMPORT int pgstat_fetch_consistency; +extern PGDLLIMPORT int pgstat_flush_interval; /* diff --git a/src/include/utils/guc_hooks.h b/src/include/utils/guc_hooks.h index b6ecb0e769f..3a2ae6c41cd 100644 --- a/src/include/utils/guc_hooks.h +++ b/src/include/utils/guc_hooks.h @@ -132,6 +132,7 @@ extern bool check_session_authorization(char **newval, void **extra, GucSource s extern void assign_session_authorization(const char *newval, void *extra); extern void assign_session_replication_role(int newval, void *extra); extern void assign_stats_fetch_consistency(int newval, void *extra); +extern void assign_stats_flush_interval(int newval, void *extra); extern bool check_ssl(bool *newval, void **extra, GucSource source); extern bool check_stage_log_stats(bool *newval, void **extra, GucSource source); extern bool check_standard_conforming_strings(bool *newval, void **extra, -- 2.34.1 --wR/mWGXukst4NraF Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="v4-0003-Remove-useless-calls-to-flush-some-stats.patch" ^ permalink raw reply [nested|flat] 15+ messages in thread
* [PATCH v7 3/5] Add GUC to specify non-transactional statistics flush interval @ 2026-01-28 07:53 Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 0 siblings, 0 replies; 15+ messages in thread From: Bertrand Drouvot @ 2026-01-28 07:53 UTC (permalink / raw) Adding pgstat_flush_interval, a new GUC to set the interval between flushes of non-transactional statistics. --- doc/src/sgml/config.sgml | 32 +++++++++++++++++++ src/backend/utils/activity/pgstat.c | 16 ++++++++++ src/backend/utils/misc/guc_parameters.dat | 10 ++++++ src/backend/utils/misc/postgresql.conf.sample | 1 + src/include/pgstat.h | 6 ++-- src/include/utils/guc_hooks.h | 1 + .../test_custom_stats/t/001_custom_stats.pl | 6 ++-- 7 files changed, 66 insertions(+), 6 deletions(-) 51.8% doc/src/sgml/ 13.3% src/backend/utils/activity/ 13.6% src/backend/utils/misc/ 11.3% src/include/ 9.8% src/test/modules/test_custom_stats/t/ diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 6bc2690ce07..383bbe3a132 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -8923,6 +8923,38 @@ COPY postgres_log FROM '/full/path/to/logfile.csv' WITH csv; </listitem> </varlistentry> + <varlistentry id="guc-stats-flush-interval" xreflabel="stats_flush_interval"> + <term><varname>stats_flush_interval</varname> (<type>integer</type>) + <indexterm> + <primary><varname>stats_flush_interval</varname> configuration parameter</primary> + </indexterm> + </term> + <listitem> + <para> + Sets the interval at which certain statistics, which can be updated while a + transaction is in progress, are made visible. These include WAL activity + and I/O operations. + Such statistics are refreshed at the specified interval and can be observed + during active transactions in monitoring views such as + <link linkend="monitoring-pg-stat-wal-view"><structname>pg_stat_wal</structname></link> + and + <link linkend="monitoring-pg-stat-io-view"><structname>pg_stat_io</structname></link>. + If the value is specified without a unit, milliseconds are assumed. + The default is 10 seconds (<literal>10s</literal>), which is generally + the smallest practical value for long-running transactions. + </para> + <note> + <para> + This parameter does not affect statistics that are only reported at + transaction end, such as the columns of <structname>pg_stat_all_tables</structname> + (for example, <structfield>n_tup_ins</structfield>, <structfield>n_tup_upd</structfield>, + and <structfield>n_tup_del</structfield>). These statistics are always + flushed at the end of a transaction. + </para> + </note> + </listitem> + </varlistentry> + </variablelist> </sect2> diff --git a/src/backend/utils/activity/pgstat.c b/src/backend/utils/activity/pgstat.c index a4ff64dc5ce..dd85a27c52f 100644 --- a/src/backend/utils/activity/pgstat.c +++ b/src/backend/utils/activity/pgstat.c @@ -123,6 +123,8 @@ * ---------- */ +/* minimum interval non-forced stats flushes.*/ +#define PGSTAT_MIN_INTERVAL 1000 /* how long until to block flushing pending stats updates */ #define PGSTAT_MAX_INTERVAL 60000 /* when to call pgstat_report_stat() again, even when idle */ @@ -203,6 +205,7 @@ static inline bool pgstat_is_kind_valid(PgStat_Kind kind); bool pgstat_track_counts = false; int pgstat_fetch_consistency = PGSTAT_FETCH_CONSISTENCY_CACHE; +int pgstat_flush_interval = 10000; /* ---------- @@ -2164,6 +2167,19 @@ assign_stats_fetch_consistency(int newval, void *extra) force_stats_snapshot_clear = true; } +/* + * GUC assign_hook for stats_flush_interval. + */ +void +assign_stats_flush_interval(int newval, void *extra) +{ + if (get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) + { + disable_timeout(ANYTIME_STATS_UPDATE_TIMEOUT, false); + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, newval); + } +} + /* * Flushes only FLUSH_ANYTIME stats using non-blocking locks. Transactional * stats (FLUSH_AT_TXN_BOUNDARY) remain pending until transaction boundary. diff --git a/src/backend/utils/misc/guc_parameters.dat b/src/backend/utils/misc/guc_parameters.dat index 271c033952e..d2734caafea 100644 --- a/src/backend/utils/misc/guc_parameters.dat +++ b/src/backend/utils/misc/guc_parameters.dat @@ -2801,6 +2801,16 @@ assign_hook => 'assign_stats_fetch_consistency', }, +{ name => 'stats_flush_interval', type => 'int', context => 'PGC_USERSET', group => 'STATS_CUMULATIVE', + short_desc => 'Sets the interval between flushes of non-transactional statistics.', + flags => 'GUC_UNIT_MS', + variable => 'pgstat_flush_interval', + boot_val => '10000', + min => '1000', + max => 'INT_MAX', + assign_hook => 'assign_stats_flush_interval' +}, + { name => 'subtransaction_buffers', type => 'int', context => 'PGC_POSTMASTER', group => 'RESOURCES_MEM', short_desc => 'Sets the size of the dedicated buffer pool used for the subtransaction cache.', long_desc => '0 means use a fraction of "shared_buffers".', diff --git a/src/backend/utils/misc/postgresql.conf.sample b/src/backend/utils/misc/postgresql.conf.sample index f938cc65a3a..8bd37a25b38 100644 --- a/src/backend/utils/misc/postgresql.conf.sample +++ b/src/backend/utils/misc/postgresql.conf.sample @@ -688,6 +688,7 @@ #track_wal_io_timing = off #track_functions = none # none, pl, all #stats_fetch_consistency = cache # cache, none, snapshot +#stats_flush_interval = 10s # in milliseconds # - Monitoring - diff --git a/src/include/pgstat.h b/src/include/pgstat.h index b340a680614..ef856dbf55b 100644 --- a/src/include/pgstat.h +++ b/src/include/pgstat.h @@ -35,9 +35,6 @@ /* Default directory to store temporary statistics data in */ #define PG_STAT_TMP_DIR "pg_stat_tmp" -/* Minimum interval non-forced stats flushes */ -#define PGSTAT_MIN_INTERVAL 1000 - /* Values for track_functions GUC variable --- order is significant! */ typedef enum TrackFunctionsLevel { @@ -548,7 +545,7 @@ extern void pgstat_force_next_flush(void); #define pgstat_schedule_anytime_update() \ do { \ if (IsUnderPostmaster && !get_timeout_active(ANYTIME_STATS_UPDATE_TIMEOUT)) \ - enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, PGSTAT_MIN_INTERVAL); \ + enable_timeout_after(ANYTIME_STATS_UPDATE_TIMEOUT, pgstat_flush_interval); \ } while (0) extern void pgstat_reset_counters(void); @@ -828,6 +825,7 @@ extern PgStat_WalStats *pgstat_fetch_stat_wal(void); extern PGDLLIMPORT bool pgstat_track_counts; extern PGDLLIMPORT int pgstat_track_functions; extern PGDLLIMPORT int pgstat_fetch_consistency; +extern PGDLLIMPORT int pgstat_flush_interval; /* diff --git a/src/include/utils/guc_hooks.h b/src/include/utils/guc_hooks.h index 9c90670d9b8..9b5d2a90387 100644 --- a/src/include/utils/guc_hooks.h +++ b/src/include/utils/guc_hooks.h @@ -132,6 +132,7 @@ extern bool check_session_authorization(char **newval, void **extra, GucSource s extern void assign_session_authorization(const char *newval, void *extra); extern void assign_session_replication_role(int newval, void *extra); extern void assign_stats_fetch_consistency(int newval, void *extra); +extern void assign_stats_flush_interval(int newval, void *extra); extern bool check_ssl(bool *newval, void **extra, GucSource source); extern bool check_stage_log_stats(bool *newval, void **extra, GucSource source); extern bool check_standard_conforming_strings(bool *newval, void **extra, diff --git a/src/test/modules/test_custom_stats/t/001_custom_stats.pl b/src/test/modules/test_custom_stats/t/001_custom_stats.pl index 7be1b281776..22e2a75dcb9 100644 --- a/src/test/modules/test_custom_stats/t/001_custom_stats.pl +++ b/src/test/modules/test_custom_stats/t/001_custom_stats.pl @@ -164,10 +164,11 @@ $node->safe_psql('postgres', q(select test_custom_stats_fixed_reset())); $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); my $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; -- Accumulate stats select test_custom_stats_fixed_anytime_update() from generate_series(1, 2); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select 'anytime:'||numcalls from test_custom_stats_fixed_report(); @@ -183,11 +184,12 @@ like($result, qr/^anytime:2/m, $node->safe_psql('postgres', q(select pg_stat_force_next_flush())); $anytime_test = q[ + SET stats_flush_interval = '1s'; BEGIN; -- Accumulate stats select test_custom_stats_var_anytime_update('entry2'); select test_custom_stats_var_anytime_update('entry2'); - -- Wait (has to be greater than PGSTAT_MIN_INTERVAL) + -- Wait (has to be greater than stats_flush_interval) select pg_sleep(1.5); -- Check select * from test_custom_stats_var_report('entry2'); -- 2.34.1 --C2xzVbxFmVrP7k6O Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="v7-0004-Remove-useless-calls-to-flush-some-stats.patch" ^ permalink raw reply [nested|flat] 15+ messages in thread
end of thread, other threads:[~2026-01-28 07:53 UTC | newest] Thread overview: 15+ messages (download: mbox mbox.gz follow: Atom feed) -- links below jump to the message on this page -- 2019-07-09 09:54 [PATCH 2/5] Remove TLI from some argument lists. Antonin Houska <ah@cybertec.at> 2019-09-09 09:53 [PATCH 1/4] Remove TLI from some argument lists. Antonin Houska <ah@cybertec.at> 2019-09-23 05:40 [PATCH 2/6] Remove TLI from some argument lists. Antonin Houska <ah@cybertec.at> 2023-06-25 11:48 [PATCH v1 5/7] Row pattern recognition patch (docs). Tatsuo Ishii <ishii@postgresql.org> 2026-01-28 07:53 [PATCH v6 3/5] Add GUC to specify non-transactional statistics flush interval Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 2026-01-28 07:53 [PATCH v11 3/5] Add GUC to specify non-transactional statistics flush interval Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 2026-01-28 07:53 [PATCH v7 3/5] Add GUC to specify non-transactional statistics flush interval Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 2026-01-28 07:53 [PATCH v10 3/5] Add GUC to specify non-transactional statistics flush interval Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 2026-01-28 07:53 [PATCH v11 3/5] Add GUC to specify non-transactional statistics flush interval Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 2026-01-28 07:53 [PATCH v9 3/5] Add GUC to specify non-transactional statistics flush interval Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 2026-01-28 07:53 [PATCH v8 3/5] Add GUC to specify non-transactional statistics flush interval Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 2026-01-28 07:53 [PATCH v5 2/4] Add GUC to specify non-transactional statistics flush interval Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 2026-01-28 07:53 [PATCH v10 3/5] Add GUC to specify non-transactional statistics flush interval Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 2026-01-28 07:53 [PATCH v4 2/4] Add GUC to specify non-transactional statistics flush interval Bertrand Drouvot <bertranddrouvot.pg@gmail.com> 2026-01-28 07:53 [PATCH v7 3/5] Add GUC to specify non-transactional statistics flush interval Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
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