diff options
Diffstat (limited to 'src/backend/storage/freespace/freespace.c')
| -rw-r--r-- | src/backend/storage/freespace/freespace.c | 179 |
1 files changed, 87 insertions, 92 deletions
diff --git a/src/backend/storage/freespace/freespace.c b/src/backend/storage/freespace/freespace.c index 11fc45ea8e7..1bc1d60d4ad 100644 --- a/src/backend/storage/freespace/freespace.c +++ b/src/backend/storage/freespace/freespace.c @@ -8,7 +8,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/storage/freespace/freespace.c,v 1.48 2005/08/20 23:26:20 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/storage/freespace/freespace.c,v 1.49 2005/10/15 02:49:25 momjian Exp $ * * * NOTES: @@ -222,7 +222,7 @@ static HTAB *FreeSpaceMapRelHash; /* points to (what used to be) static void CheckFreeSpaceMapStatistics(int elevel, int numRels, - double needed); + double needed); static FSMRelation *lookup_fsm_rel(RelFileNode *rel); static FSMRelation *create_fsm_rel(RelFileNode *rel); static void delete_fsm_rel(FSMRelation *fsmrel); @@ -295,7 +295,7 @@ InitFreeSpaceMap(void) if (!FreeSpaceMapRelHash) ereport(FATAL, (errcode(ERRCODE_OUT_OF_MEMORY), - errmsg("insufficient shared memory for free space map"))); + errmsg("insufficient shared memory for free space map"))); if (found) return; @@ -307,14 +307,14 @@ InitFreeSpaceMap(void) if (nchunks <= MaxFSMRelations) ereport(FATAL, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), - errmsg("max_fsm_pages must exceed max_fsm_relations * %d", - CHUNKPAGES))); + errmsg("max_fsm_pages must exceed max_fsm_relations * %d", + CHUNKPAGES))); FreeSpaceMap->arena = (char *) ShmemAlloc((Size) nchunks * CHUNKBYTES); if (FreeSpaceMap->arena == NULL) ereport(FATAL, (errcode(ERRCODE_OUT_OF_MEMORY), - errmsg("insufficient shared memory for free space map"))); + errmsg("insufficient shared memory for free space map"))); FreeSpaceMap->totalChunks = nchunks; FreeSpaceMap->usedChunks = 0; @@ -371,10 +371,10 @@ GetPageWithFreeSpace(RelFileNode *rel, Size spaceNeeded) fsmrel = create_fsm_rel(rel); /* - * Update the moving average of space requests. This code implements - * an exponential moving average with an equivalent period of about 63 - * requests. Ignore silly requests, however, to ensure that the - * average stays sane. + * Update the moving average of space requests. This code implements an + * exponential moving average with an equivalent period of about 63 + * requests. Ignore silly requests, however, to ensure that the average + * stays sane. */ if (spaceNeeded > 0 && spaceNeeded < BLCKSZ) { @@ -478,10 +478,10 @@ RecordRelationFreeSpace(RelFileNode *rel, LWLockAcquire(FreeSpaceLock, LW_EXCLUSIVE); /* - * Note we don't record info about a relation unless there's already - * an FSM entry for it, implying someone has done GetPageWithFreeSpace - * for it. Inactive rels thus will not clutter the map simply by - * being vacuumed. + * Note we don't record info about a relation unless there's already an + * FSM entry for it, implying someone has done GetPageWithFreeSpace for + * it. Inactive rels thus will not clutter the map simply by being + * vacuumed. */ fsmrel = lookup_fsm_rel(rel); if (fsmrel) @@ -494,8 +494,8 @@ RecordRelationFreeSpace(RelFileNode *rel, curAllocPages = curAlloc * CHUNKPAGES; /* - * If the data fits in our current allocation, just copy it; - * otherwise must compress. + * If the data fits in our current allocation, just copy it; otherwise + * must compress. */ newLocation = (FSMPageData *) (FreeSpaceMap->arena + fsmrel->firstChunk * CHUNKBYTES); @@ -567,10 +567,9 @@ RecordIndexFreeSpace(RelFileNode *rel, LWLockAcquire(FreeSpaceLock, LW_EXCLUSIVE); /* - * Note we don't record info about a relation unless there's already - * an FSM entry for it, implying someone has done GetFreeIndexPage for - * it. Inactive rels thus will not clutter the map simply by being - * vacuumed. + * Note we don't record info about a relation unless there's already an + * FSM entry for it, implying someone has done GetFreeIndexPage for it. + * Inactive rels thus will not clutter the map simply by being vacuumed. */ fsmrel = lookup_fsm_rel(rel); if (fsmrel) @@ -584,9 +583,9 @@ RecordIndexFreeSpace(RelFileNode *rel, curAllocPages = curAlloc * INDEXCHUNKPAGES; /* - * If the data fits in our current allocation, just copy it; - * otherwise must compress. But compression is easy: we merely - * forget extra pages. + * If the data fits in our current allocation, just copy it; otherwise + * must compress. But compression is easy: we merely forget extra + * pages. */ newLocation = (IndexFSMPageData *) (FreeSpaceMap->arena + fsmrel->firstChunk * CHUNKBYTES); @@ -708,34 +707,34 @@ PrintFreeSpaceMapStatistics(int elevel) ereport(elevel, (errmsg("free space map contains %d pages in %d relations", storedPages, numRels), - errdetail("A total of %.0f page slots are in use (including overhead).\n" - "%.0f page slots are required to track all free space.\n" - "Current limits are: %d page slots, %d relations, using %.0f KB.", - Min(needed, MaxFSMPages), - needed, MaxFSMPages, MaxFSMRelations, - (double) FreeSpaceShmemSize() / 1024.0))); + errdetail("A total of %.0f page slots are in use (including overhead).\n" + "%.0f page slots are required to track all free space.\n" + "Current limits are: %d page slots, %d relations, using %.0f KB.", + Min(needed, MaxFSMPages), + needed, MaxFSMPages, MaxFSMRelations, + (double) FreeSpaceShmemSize() / 1024.0))); CheckFreeSpaceMapStatistics(NOTICE, numRels, needed); /* Print to server logs too because is deals with a config variable. */ CheckFreeSpaceMapStatistics(LOG, numRels, needed); } - + static void CheckFreeSpaceMapStatistics(int elevel, int numRels, double needed) { - if (numRels == MaxFSMRelations) + if (numRels == MaxFSMRelations) ereport(elevel, - (errmsg("max_fsm_relations(%d) equals the number of relations checked", - MaxFSMRelations), - errhint("You have >= %d relations.\n" - "Consider increasing the configuration parameter \"max_fsm_relations\".", - numRels))); + (errmsg("max_fsm_relations(%d) equals the number of relations checked", + MaxFSMRelations), + errhint("You have >= %d relations.\n" + "Consider increasing the configuration parameter \"max_fsm_relations\".", + numRels))); else if (needed > MaxFSMPages) ereport(elevel, - (errmsg("the number of page slots needed (%.0f) exceeds max_fsm_pages (%d)", - needed, MaxFSMPages), - errhint("Consider increasing the configuration parameter \"max_fsm_pages\"\n" - "to a value over %.0f.", needed))); + (errmsg("the number of page slots needed (%.0f) exceeds max_fsm_pages (%d)", + needed, MaxFSMPages), + errhint("Consider increasing the configuration parameter \"max_fsm_pages\"\n" + "to a value over %.0f.", needed))); } /* @@ -753,7 +752,7 @@ DumpFreeSpaceMap(int code, Datum arg) FSMRelation *fsmrel; /* Try to create file */ - unlink(FSM_CACHE_FILENAME); /* in case it exists w/wrong permissions */ + unlink(FSM_CACHE_FILENAME); /* in case it exists w/wrong permissions */ fp = AllocateFile(FSM_CACHE_FILENAME, PG_BINARY_W); if (fp == NULL) @@ -917,11 +916,11 @@ LoadFreeSpaceMap(void) } /* - * Okay, create the FSM entry and insert data into it. Since the - * rels were stored in reverse usage order, at the end of the loop - * they will be correctly usage-ordered in memory; and if - * MaxFSMRelations is less than it used to be, we will correctly - * drop the least recently used ones. + * Okay, create the FSM entry and insert data into it. Since the rels + * were stored in reverse usage order, at the end of the loop they + * will be correctly usage-ordered in memory; and if MaxFSMRelations + * is less than it used to be, we will correctly drop the least + * recently used ones. */ fsmrel = create_fsm_rel(&relheader.key); fsmrel->avgRequest = relheader.avgRequest; @@ -936,8 +935,8 @@ LoadFreeSpaceMap(void) /* * If the data fits in our current allocation, just copy it; - * otherwise must compress. But compression is easy: we - * merely forget extra pages. + * otherwise must compress. But compression is easy: we merely + * forget extra pages. */ newLocation = (IndexFSMPageData *) (FreeSpaceMap->arena + fsmrel->firstChunk * CHUNKBYTES); @@ -1105,10 +1104,10 @@ realloc_fsm_rel(FSMRelation *fsmrel, int nPages, bool isIndex) myAlloc = fsm_calc_target_allocation(myRequest); /* - * Need to reallocate space if (a) my target allocation is more than - * my current allocation, AND (b) my actual immediate need - * (myRequest+1 chunks) is more than my current allocation. Otherwise - * just store the new data in-place. + * Need to reallocate space if (a) my target allocation is more than my + * current allocation, AND (b) my actual immediate need (myRequest+1 + * chunks) is more than my current allocation. Otherwise just store the + * new data in-place. */ curAlloc = fsm_current_allocation(fsmrel); if (myAlloc > curAlloc && (myRequest + 1) > curAlloc && nPages > 0) @@ -1241,8 +1240,7 @@ find_free_space(FSMRelation *fsmrel, Size spaceNeeded) if (spaceAvail >= spaceNeeded) { /* - * Found what we want --- adjust the entry, and update - * nextPage. + * Found what we want --- adjust the entry, and update nextPage. */ FSMPageSetSpace(page, spaceAvail - spaceNeeded); fsmrel->nextPage = pageIndex + 1; @@ -1266,10 +1264,10 @@ find_index_free_space(FSMRelation *fsmrel) BlockNumber result; /* - * If isIndex isn't set, it could be that RecordIndexFreeSpace() has - * never yet been called on this relation, and we're still looking at - * the default setting from create_fsm_rel(). If so, just act as - * though there's no space. + * If isIndex isn't set, it could be that RecordIndexFreeSpace() has never + * yet been called on this relation, and we're still looking at the + * default setting from create_fsm_rel(). If so, just act as though + * there's no space. */ if (!fsmrel->isIndex) { @@ -1279,10 +1277,10 @@ find_index_free_space(FSMRelation *fsmrel) } /* - * For indexes, there's no need for the nextPage state variable; we - * just remove and return the first available page. (We could save - * cycles here by returning the last page, but it seems better to - * encourage re-use of lower-numbered pages.) + * For indexes, there's no need for the nextPage state variable; we just + * remove and return the first available page. (We could save cycles here + * by returning the last page, but it seems better to encourage re-use of + * lower-numbered pages.) */ if (fsmrel->storedPages <= 0) return InvalidBlockNumber; /* no pages available */ @@ -1318,10 +1316,10 @@ fsm_record_free_space(FSMRelation *fsmrel, BlockNumber page, Size spaceAvail) else { /* - * No existing entry; ignore the call. We used to add the page to - * the FSM --- but in practice, if the page hasn't got enough - * space to satisfy the caller who's kicking it back to us, then - * it's probably uninteresting to everyone else as well. + * No existing entry; ignore the call. We used to add the page to the + * FSM --- but in practice, if the page hasn't got enough space to + * satisfy the caller who's kicking it back to us, then it's probably + * uninteresting to everyone else as well. */ } } @@ -1454,25 +1452,23 @@ compact_fsm_storage(void) /* * It's possible that we have to move data down, not up, if the - * allocations of previous rels expanded. This normally means - * that our allocation expanded too (or at least got no worse), - * and ditto for later rels. So there should be room to move all - * our data down without dropping any --- but we might have to - * push down following rels to acquire the room. We don't want to - * do the push more than once, so pack everything against the end - * of the arena if so. + * allocations of previous rels expanded. This normally means that + * our allocation expanded too (or at least got no worse), and ditto + * for later rels. So there should be room to move all our data down + * without dropping any --- but we might have to push down following + * rels to acquire the room. We don't want to do the push more than + * once, so pack everything against the end of the arena if so. * * In corner cases where we are on the short end of a roundoff choice * that we were formerly on the long end of, it's possible that we - * have to move down and compress our data too. In fact, even - * after pushing down the following rels, there might not be as - * much space as we computed for this rel above --- that would - * imply that some following rel(s) are also on the losing end of - * roundoff choices. We could handle this fairly by doing the - * per-rel compactions out-of-order, but that seems like way too - * much complexity to deal with a very infrequent corner case. - * Instead, we simply drop pages from the end of the current rel's - * data until it fits. + * have to move down and compress our data too. In fact, even after + * pushing down the following rels, there might not be as much space + * as we computed for this rel above --- that would imply that some + * following rel(s) are also on the losing end of roundoff choices. We + * could handle this fairly by doing the per-rel compactions + * out-of-order, but that seems like way too much complexity to deal + * with a very infrequent corner case. Instead, we simply drop pages + * from the end of the current rel's data until it fits. */ if (newChunkIndex > oldChunkIndex) { @@ -1508,12 +1504,11 @@ compact_fsm_storage(void) newAlloc = limitChunkIndex - newChunkIndex; /* - * If newAlloc < 0 at this point, we are moving the - * rel's firstChunk into territory currently assigned - * to a later rel. This is okay so long as we do not - * copy any data. The rels will be back in - * nondecreasing firstChunk order at completion of the - * compaction pass. + * If newAlloc < 0 at this point, we are moving the rel's + * firstChunk into territory currently assigned to a later + * rel. This is okay so long as we do not copy any data. + * The rels will be back in nondecreasing firstChunk order + * at completion of the compaction pass. */ if (newAlloc < 0) newAlloc = 0; @@ -1530,9 +1525,9 @@ compact_fsm_storage(void) else if (newAllocPages < fsmrel->storedPages) { /* - * Need to compress the page data. For an index, - * "compression" just means dropping excess pages; otherwise - * we try to keep the ones with the most space. + * Need to compress the page data. For an index, "compression" + * just means dropping excess pages; otherwise we try to keep the + * ones with the most space. */ if (fsmrel->isIndex) { @@ -1863,7 +1858,7 @@ DumpFreeSpace(void) relNum++; fprintf(stderr, "Map %d: rel %u/%u/%u isIndex %d avgRequest %u lastPageCount %d nextPage %d\nMap= ", relNum, - fsmrel->key.spcNode, fsmrel->key.dbNode, fsmrel->key.relNode, + fsmrel->key.spcNode, fsmrel->key.dbNode, fsmrel->key.relNode, (int) fsmrel->isIndex, fsmrel->avgRequest, fsmrel->lastPageCount, fsmrel->nextPage); if (fsmrel->isIndex) |