diff options
Diffstat (limited to 'src/backend/commands/vacuum.c')
| -rw-r--r-- | src/backend/commands/vacuum.c | 42 |
1 files changed, 33 insertions, 9 deletions
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c index 8b8cff6d30..03bd3de328 100644 --- a/src/backend/commands/vacuum.c +++ b/src/backend/commands/vacuum.c @@ -13,7 +13,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.250 2003/02/24 00:57:17 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.251 2003/03/04 21:51:20 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -337,6 +337,13 @@ vacuum(VacuumStmt *vacstmt) StartTransactionCommand(true); /* + * If it was a database-wide VACUUM, print FSM usage statistics + * (we don't make you be superuser to see these). + */ + if (vacstmt->relation == NULL) + PrintFreeSpaceMapStatistics(elevel); + + /* * If we completed a database-wide VACUUM without skipping any * relations, update the database's pg_database row with info * about the transaction IDs used, and try to truncate pg_clog. @@ -2781,31 +2788,48 @@ vac_update_fsm(Relation onerel, VacPageList fraged_pages, BlockNumber rel_pages) { int nPages = fraged_pages->num_pages; - int i; + VacPage *pagedesc = fraged_pages->pagedesc; + Size threshold; PageFreeSpaceInfo *pageSpaces; + int outPages; + int i; + + /* + * We only report pages with free space at least equal to the average + * request size --- this avoids cluttering FSM with uselessly-small bits + * of space. Although FSM would discard pages with little free space + * anyway, it's important to do this prefiltering because (a) it reduces + * the time spent holding the FSM lock in RecordRelationFreeSpace, and + * (b) FSM uses the number of pages reported as a statistic for guiding + * space management. If we didn't threshold our reports the same way + * vacuumlazy.c does, we'd be skewing that statistic. + */ + threshold = GetAvgFSMRequestSize(&onerel->rd_node); /* +1 to avoid palloc(0) */ pageSpaces = (PageFreeSpaceInfo *) palloc((nPages + 1) * sizeof(PageFreeSpaceInfo)); + outPages = 0; for (i = 0; i < nPages; i++) { - pageSpaces[i].blkno = fraged_pages->pagedesc[i]->blkno; - pageSpaces[i].avail = fraged_pages->pagedesc[i]->free; - /* * fraged_pages may contain entries for pages that we later * decided to truncate from the relation; don't enter them into * the free space map! */ - if (pageSpaces[i].blkno >= rel_pages) - { - nPages = i; + if (pagedesc[i]->blkno >= rel_pages) break; + + if (pagedesc[i]->free >= threshold) + { + pageSpaces[outPages].blkno = pagedesc[i]->blkno; + pageSpaces[outPages].avail = pagedesc[i]->free; + outPages++; } } - MultiRecordFreeSpace(&onerel->rd_node, 0, nPages, pageSpaces); + RecordRelationFreeSpace(&onerel->rd_node, outPages, pageSpaces); pfree(pageSpaces); } |