* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/storage/freespace/freespace.c,v 1.38 2005/03/12 05:21:52 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/storage/freespace/freespace.c,v 1.49 2005/10/15 02:49:25 momjian Exp $
*
*
* NOTES:
* FSMHeader->relHash */
+static void CheckFreeSpaceMapStatistics(int elevel, int numRels,
+ double needed);
static FSMRelation *lookup_fsm_rel(RelFileNode *rel);
static FSMRelation *create_fsm_rel(RelFileNode *rel);
static void delete_fsm_rel(FSMRelation *fsmrel);
bool found;
/* Create table header */
- FreeSpaceMap = (FSMHeader *) ShmemInitStruct("Free Space Map Header", sizeof(FSMHeader), &found);
+ FreeSpaceMap = (FSMHeader *) ShmemInitStruct("Free Space Map Header",
+ sizeof(FSMHeader),
+ &found);
if (FreeSpaceMap == NULL)
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)
MemSet(FreeSpaceMap, 0, sizeof(FSMHeader));
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;
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(nchunks * CHUNKBYTES);
+ 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;
/*
* Estimate amount of shmem space needed for FSM.
*/
-int
+Size
FreeSpaceShmemSize(void)
{
- int size;
+ Size size;
int nchunks;
/* table header */
size = MAXALIGN(sizeof(FSMHeader));
/* hash table, including the FSMRelation objects */
- size += hash_estimate_size(MaxFSMRelations + 1, sizeof(FSMRelation));
+ size = add_size(size, hash_estimate_size(MaxFSMRelations + 1,
+ sizeof(FSMRelation)));
/* page-storage arena */
nchunks = (MaxFSMPages - 1) / CHUNKPAGES + 1;
-
- if (nchunks >= (INT_MAX / CHUNKBYTES))
- ereport(FATAL,
- (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
- errmsg("max_fsm_pages is too large")));
-
- size += MAXALIGN(nchunks * CHUNKBYTES);
+ size = add_size(size, mul_size(nchunks, CHUNKBYTES));
return size;
}
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)
{
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)
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);
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)
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);
fsmrel != NULL;
fsmrel = fsmrel->nextPhysical)
storedPages += fsmrel->storedPages;
+
/* Copy other stats before dropping lock */
numRels = FreeSpaceMap->numRels;
sumRequests = FreeSpaceMap->sumRequests;
needed = (sumRequests + numRels) * CHUNKPAGES;
ereport(elevel,
- (errmsg("free space map: %d relations, %d pages stored; %.0f total pages used",
- numRels, storedPages, needed),
- errdetail("FSM size: %d relations + %d pages = %.0f kB shared memory.",
- MaxFSMRelations, MaxFSMPages,
- (double) FreeSpaceShmemSize() / 1024.0)));
-
+ (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)));
+
+ 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)
- ereport(NOTICE,
- (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)));
+ 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)));
else if (needed > MaxFSMPages)
- ereport(NOTICE,
- (errmsg("the number of page slots needed (%.0f) exceeds max_fsm_pages (%d)",
- needed,MaxFSMPages),
- errhint("Consider increasing the configuration parameter \"max_fsm_relations\"\n"
- "to a value over %.0f.", needed)));
+ 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)));
}
/*
DumpFreeSpaceMap(int code, Datum arg)
{
FILE *fp;
- char cachefilename[MAXPGPATH];
FsmCacheFileHeader header;
FSMRelation *fsmrel;
/* Try to create file */
- snprintf(cachefilename, sizeof(cachefilename), "%s/%s",
- DataDir, FSM_CACHE_FILENAME);
+ unlink(FSM_CACHE_FILENAME); /* in case it exists w/wrong permissions */
- unlink(cachefilename); /* in case it exists w/wrong permissions */
-
- fp = AllocateFile(cachefilename, PG_BINARY_W);
+ fp = AllocateFile(FSM_CACHE_FILENAME, PG_BINARY_W);
if (fp == NULL)
{
- elog(LOG, "could not write \"%s\": %m", cachefilename);
+ elog(LOG, "could not write \"%s\": %m", FSM_CACHE_FILENAME);
return;
}
if (FreeFile(fp))
{
- elog(LOG, "could not write \"%s\": %m", cachefilename);
+ elog(LOG, "could not write \"%s\": %m", FSM_CACHE_FILENAME);
/* Remove busted cache file */
- unlink(cachefilename);
+ unlink(FSM_CACHE_FILENAME);
}
return;
write_failed:
- elog(LOG, "could not write \"%s\": %m", cachefilename);
+ elog(LOG, "could not write \"%s\": %m", FSM_CACHE_FILENAME);
/* Clean up */
LWLockRelease(FreeSpaceLock);
FreeFile(fp);
/* Remove busted cache file */
- unlink(cachefilename);
+ unlink(FSM_CACHE_FILENAME);
}
/*
LoadFreeSpaceMap(void)
{
FILE *fp;
- char cachefilename[MAXPGPATH];
FsmCacheFileHeader header;
int relno;
/* Try to open file */
- snprintf(cachefilename, sizeof(cachefilename), "%s/%s",
- DataDir, FSM_CACHE_FILENAME);
-
- fp = AllocateFile(cachefilename, PG_BINARY_R);
+ fp = AllocateFile(FSM_CACHE_FILENAME, PG_BINARY_R);
if (fp == NULL)
{
if (errno != ENOENT)
- elog(LOG, "could not read \"%s\": %m", cachefilename);
+ elog(LOG, "could not read \"%s\": %m", FSM_CACHE_FILENAME);
return;
}
header.version != FSM_CACHE_VERSION ||
header.numRels < 0)
{
- elog(LOG, "bogus file header in \"%s\"", cachefilename);
+ elog(LOG, "bogus file header in \"%s\"", FSM_CACHE_FILENAME);
goto read_failed;
}
relheader.lastPageCount < 0 ||
relheader.storedPages < 0)
{
- elog(LOG, "bogus rel header in \"%s\"", cachefilename);
+ elog(LOG, "bogus rel header in \"%s\"", FSM_CACHE_FILENAME);
goto read_failed;
}
data = (char *) palloc(len);
if (fread(data, 1, len, fp) != len)
{
- elog(LOG, "premature EOF in \"%s\"", cachefilename);
+ elog(LOG, "premature EOF in \"%s\"", FSM_CACHE_FILENAME);
pfree(data);
goto read_failed;
}
/*
- * 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;
/*
* 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);
FreeFile(fp);
/* Remove cache file before it can become stale; see notes above */
- unlink(cachefilename);
+ unlink(FSM_CACHE_FILENAME);
}
(void *) rel,
HASH_ENTER,
&found);
- if (!fsmrel)
- ereport(ERROR,
- (errcode(ERRCODE_OUT_OF_MEMORY),
- errmsg("out of shared memory")));
if (!found)
{
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)
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;
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)
{
}
/*
- * 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 */
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.
*/
}
}
/*
* 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)
{
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;
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)
{
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)
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