Header And Logo
|
#include "postgres.h"#include "access/heapam_xlog.h"#include "access/nbtree.h"#include "access/relscan.h"#include "catalog/index.h"#include "commands/vacuum.h"#include "storage/indexfsm.h"#include "storage/ipc.h"#include "storage/lmgr.h"#include "storage/smgr.h"#include "tcop/tcopprot.h"#include "utils/memutils.h"
Go to the source code of this file.
Data Structures | |
| struct | BTBuildState |
| struct | BTVacState |
Functions | |
| static void | btbuildCallback (Relation index, HeapTuple htup, Datum *values, bool *isnull, bool tupleIsAlive, void *state) |
| static void | btvacuumscan (IndexVacuumInfo *info, IndexBulkDeleteResult *stats, IndexBulkDeleteCallback callback, void *callback_state, BTCycleId cycleid) |
| static void | btvacuumpage (BTVacState *vstate, BlockNumber blkno, BlockNumber orig_blkno) |
| Datum | btbuild (PG_FUNCTION_ARGS) |
| Datum | btbuildempty (PG_FUNCTION_ARGS) |
| Datum | btinsert (PG_FUNCTION_ARGS) |
| Datum | btgettuple (PG_FUNCTION_ARGS) |
| Datum | btgetbitmap (PG_FUNCTION_ARGS) |
| Datum | btbeginscan (PG_FUNCTION_ARGS) |
| Datum | btrescan (PG_FUNCTION_ARGS) |
| Datum | btendscan (PG_FUNCTION_ARGS) |
| Datum | btmarkpos (PG_FUNCTION_ARGS) |
| Datum | btrestrpos (PG_FUNCTION_ARGS) |
| Datum | btbulkdelete (PG_FUNCTION_ARGS) |
| Datum | btvacuumcleanup (PG_FUNCTION_ARGS) |
| Datum | btcanreturn (PG_FUNCTION_ARGS) |
| Datum btbeginscan | ( | PG_FUNCTION_ARGS | ) |
Definition at line 406 of file nbtree.c.
References BTScanOpaqueData::arrayContext, BTScanOpaqueData::arrayKeyData, BTScanOpaqueData::arrayKeys, Assert, BTScanPosData::buf, BTScanOpaqueData::currPos, BTScanOpaqueData::currTuples, BTScanOpaqueData::keyData, BTScanOpaqueData::killedItems, BTScanOpaqueData::markPos, BTScanOpaqueData::markTuples, BTScanPosData::nextTupleOffset, BTScanOpaqueData::numArrayKeys, IndexScanDescData::numberOfKeys, BTScanOpaqueData::numKilled, IndexScanDescData::opaque, palloc(), PG_GETARG_INT32, PG_GETARG_POINTER, PG_RETURN_POINTER, RelationGetDescr, RelationGetIndexScan(), and IndexScanDescData::xs_itupdesc.
{
Relation rel = (Relation) PG_GETARG_POINTER(0);
int nkeys = PG_GETARG_INT32(1);
int norderbys = PG_GETARG_INT32(2);
IndexScanDesc scan;
BTScanOpaque so;
/* no order by operators allowed */
Assert(norderbys == 0);
/* get the scan */
scan = RelationGetIndexScan(rel, nkeys, norderbys);
/* allocate private workspace */
so = (BTScanOpaque) palloc(sizeof(BTScanOpaqueData));
so->currPos.buf = so->markPos.buf = InvalidBuffer;
if (scan->numberOfKeys > 0)
so->keyData = (ScanKey) palloc(scan->numberOfKeys * sizeof(ScanKeyData));
else
so->keyData = NULL;
so->arrayKeyData = NULL; /* assume no array keys for now */
so->numArrayKeys = 0;
so->arrayKeys = NULL;
so->arrayContext = NULL;
so->killedItems = NULL; /* until needed */
so->numKilled = 0;
/*
* We don't know yet whether the scan will be index-only, so we do not
* allocate the tuple workspace arrays until btrescan. However, we set up
* scan->xs_itupdesc whether we'll need it or not, since that's so cheap.
*/
so->currTuples = so->markTuples = NULL;
so->currPos.nextTupleOffset = 0;
so->markPos.nextTupleOffset = 0;
scan->xs_itupdesc = RelationGetDescr(rel);
scan->opaque = so;
PG_RETURN_POINTER(scan);
}
| Datum btbuild | ( | PG_FUNCTION_ARGS | ) |
Definition at line 83 of file nbtree.c.
References _bt_leafbuild(), _bt_spooldestroy(), _bt_spoolinit(), btbuildCallback(), elog, ERROR, BTBuildState::haveDead, IndexBuildResult::heap_tuples, BTBuildState::heapRel, IndexInfo::ii_Unique, IndexBuildResult::index_tuples, IndexBuildHeapScan(), BTBuildState::indtuples, BTBuildState::isUnique, log_btree_build_stats, palloc(), PG_GETARG_POINTER, PG_RETURN_POINTER, RelationGetNumberOfBlocks, RelationGetRelationName, ResetUsage(), ShowUsage(), BTBuildState::spool, and BTBuildState::spool2.
{
Relation heap = (Relation) PG_GETARG_POINTER(0);
Relation index = (Relation) PG_GETARG_POINTER(1);
IndexInfo *indexInfo = (IndexInfo *) PG_GETARG_POINTER(2);
IndexBuildResult *result;
double reltuples;
BTBuildState buildstate;
buildstate.isUnique = indexInfo->ii_Unique;
buildstate.haveDead = false;
buildstate.heapRel = heap;
buildstate.spool = NULL;
buildstate.spool2 = NULL;
buildstate.indtuples = 0;
#ifdef BTREE_BUILD_STATS
if (log_btree_build_stats)
ResetUsage();
#endif /* BTREE_BUILD_STATS */
/*
* We expect to be called exactly once for any index relation. If that's
* not the case, big trouble's what we have.
*/
if (RelationGetNumberOfBlocks(index) != 0)
elog(ERROR, "index \"%s\" already contains data",
RelationGetRelationName(index));
buildstate.spool = _bt_spoolinit(heap, index, indexInfo->ii_Unique, false);
/*
* If building a unique index, put dead tuples in a second spool to keep
* them out of the uniqueness check.
*/
if (indexInfo->ii_Unique)
buildstate.spool2 = _bt_spoolinit(heap, index, false, true);
/* do the heap scan */
reltuples = IndexBuildHeapScan(heap, index, indexInfo, true,
btbuildCallback, (void *) &buildstate);
/* okay, all heap tuples are indexed */
if (buildstate.spool2 && !buildstate.haveDead)
{
/* spool2 turns out to be unnecessary */
_bt_spooldestroy(buildstate.spool2);
buildstate.spool2 = NULL;
}
/*
* Finish the build by (1) completing the sort of the spool file, (2)
* inserting the sorted tuples into btree pages and (3) building the upper
* levels.
*/
_bt_leafbuild(buildstate.spool, buildstate.spool2);
_bt_spooldestroy(buildstate.spool);
if (buildstate.spool2)
_bt_spooldestroy(buildstate.spool2);
#ifdef BTREE_BUILD_STATS
if (log_btree_build_stats)
{
ShowUsage("BTREE BUILD STATS");
ResetUsage();
}
#endif /* BTREE_BUILD_STATS */
/*
* If we are reindexing a pre-existing index, it is critical to send out a
* relcache invalidation SI message to ensure all backends re-read the
* index metapage. We expect that the caller will ensure that happens
* (typically as a side effect of updating index stats, but it must happen
* even if the stats don't change!)
*/
/*
* Return statistics
*/
result = (IndexBuildResult *) palloc(sizeof(IndexBuildResult));
result->heap_tuples = reltuples;
result->index_tuples = buildstate.indtuples;
PG_RETURN_POINTER(result);
}
| static void btbuildCallback | ( | Relation | index, | |
| HeapTuple | htup, | |||
| Datum * | values, | |||
| bool * | isnull, | |||
| bool | tupleIsAlive, | |||
| void * | state | |||
| ) | [static] |
Definition at line 174 of file nbtree.c.
References _bt_spool(), BTBuildState::haveDead, index_form_tuple(), BTBuildState::indtuples, NULL, pfree(), RelationGetDescr, BTBuildState::spool, BTBuildState::spool2, HeapTupleData::t_self, and IndexTupleData::t_tid.
Referenced by btbuild().
{
BTBuildState *buildstate = (BTBuildState *) state;
IndexTuple itup;
/* form an index tuple and point it at the heap tuple */
itup = index_form_tuple(RelationGetDescr(index), values, isnull);
itup->t_tid = htup->t_self;
/*
* insert the index tuple into the appropriate spool file for subsequent
* processing
*/
if (tupleIsAlive || buildstate->spool2 == NULL)
_bt_spool(itup, buildstate->spool);
else
{
/* dead tuples are put into spool2 */
buildstate->haveDead = true;
_bt_spool(itup, buildstate->spool2);
}
buildstate->indtuples += 1;
pfree(itup);
}
| Datum btbuildempty | ( | PG_FUNCTION_ARGS | ) |
Definition at line 210 of file nbtree.c.
References _bt_initmetapage(), BTREE_METAPAGE, INIT_FORKNUM, log_newpage(), RelFileNodeBackend::node, P_NONE, PageSetChecksumInplace(), palloc(), PG_GETARG_POINTER, PG_RETURN_VOID, RelationData::rd_smgr, SMgrRelationData::smgr_rnode, smgrimmedsync(), smgrwrite(), and XLogIsNeeded.
{
Relation index = (Relation) PG_GETARG_POINTER(0);
Page metapage;
/* Construct metapage. */
metapage = (Page) palloc(BLCKSZ);
_bt_initmetapage(metapage, P_NONE, 0);
/* Write the page. If archiving/streaming, XLOG it. */
PageSetChecksumInplace(metapage, BTREE_METAPAGE);
smgrwrite(index->rd_smgr, INIT_FORKNUM, BTREE_METAPAGE,
(char *) metapage, true);
if (XLogIsNeeded())
log_newpage(&index->rd_smgr->smgr_rnode.node, INIT_FORKNUM,
BTREE_METAPAGE, metapage);
/*
* An immediate sync is require even if we xlog'd the page, because the
* write did not go through shared_buffers and therefore a concurrent
* checkpoint may have move the redo pointer past our xlog record.
*/
smgrimmedsync(index->rd_smgr, INIT_FORKNUM);
PG_RETURN_VOID();
}
| Datum btbulkdelete | ( | PG_FUNCTION_ARGS | ) |
Definition at line 653 of file nbtree.c.
References _bt_end_vacuum(), _bt_end_vacuum_callback(), _bt_start_vacuum(), btvacuumscan(), callback(), IndexVacuumInfo::index, NULL, palloc0(), PG_END_ENSURE_ERROR_CLEANUP, PG_ENSURE_ERROR_CLEANUP, PG_GETARG_POINTER, PG_RETURN_POINTER, and PointerGetDatum.
{
IndexVacuumInfo *info = (IndexVacuumInfo *) PG_GETARG_POINTER(0);
IndexBulkDeleteResult *volatile stats = (IndexBulkDeleteResult *) PG_GETARG_POINTER(1);
IndexBulkDeleteCallback callback = (IndexBulkDeleteCallback) PG_GETARG_POINTER(2);
void *callback_state = (void *) PG_GETARG_POINTER(3);
Relation rel = info->index;
BTCycleId cycleid;
/* allocate stats if first time through, else re-use existing struct */
if (stats == NULL)
stats = (IndexBulkDeleteResult *) palloc0(sizeof(IndexBulkDeleteResult));
/* Establish the vacuum cycle ID to use for this scan */
/* The ENSURE stuff ensures we clean up shared memory on failure */
PG_ENSURE_ERROR_CLEANUP(_bt_end_vacuum_callback, PointerGetDatum(rel));
{
cycleid = _bt_start_vacuum(rel);
btvacuumscan(info, stats, callback, callback_state, cycleid);
}
PG_END_ENSURE_ERROR_CLEANUP(_bt_end_vacuum_callback, PointerGetDatum(rel));
_bt_end_vacuum(rel);
PG_RETURN_POINTER(stats);
}
| Datum btcanreturn | ( | PG_FUNCTION_ARGS | ) |
| Datum btendscan | ( | PG_FUNCTION_ARGS | ) |
Definition at line 523 of file nbtree.c.
References _bt_killitems(), BTScanOpaqueData::arrayContext, BTScanPosIsValid, BTScanPosData::buf, BTScanOpaqueData::currPos, BTScanOpaqueData::currTuples, BTScanOpaqueData::keyData, BTScanOpaqueData::killedItems, BTScanOpaqueData::markItemIndex, BTScanOpaqueData::markPos, MemoryContextDelete(), NULL, BTScanOpaqueData::numKilled, IndexScanDescData::opaque, pfree(), PG_GETARG_POINTER, PG_RETURN_VOID, and ReleaseBuffer().
{
IndexScanDesc scan = (IndexScanDesc) PG_GETARG_POINTER(0);
BTScanOpaque so = (BTScanOpaque) scan->opaque;
/* we aren't holding any read locks, but gotta drop the pins */
if (BTScanPosIsValid(so->currPos))
{
/* Before leaving current page, deal with any killed items */
if (so->numKilled > 0)
_bt_killitems(scan, false);
ReleaseBuffer(so->currPos.buf);
so->currPos.buf = InvalidBuffer;
}
if (BTScanPosIsValid(so->markPos))
{
ReleaseBuffer(so->markPos.buf);
so->markPos.buf = InvalidBuffer;
}
so->markItemIndex = -1;
/* Release storage */
if (so->keyData != NULL)
pfree(so->keyData);
/* so->arrayKeyData and so->arrayKeys are in arrayContext */
if (so->arrayContext != NULL)
MemoryContextDelete(so->arrayContext);
if (so->killedItems != NULL)
pfree(so->killedItems);
if (so->currTuples != NULL)
pfree(so->currTuples);
/* so->markTuples should not be pfree'd, see btrescan */
pfree(so);
PG_RETURN_VOID();
}
| Datum btgetbitmap | ( | PG_FUNCTION_ARGS | ) |
Definition at line 346 of file nbtree.c.
References _bt_advance_array_keys(), _bt_first(), _bt_next(), _bt_start_array_keys(), BTScanOpaqueData::currPos, ForwardScanDirection, BTScanPosItem::heapTid, BTScanPosData::itemIndex, BTScanPosData::items, BTScanPosData::lastItem, BTScanOpaqueData::numArrayKeys, IndexScanDescData::opaque, PG_GETARG_POINTER, PG_RETURN_INT64, HeapTupleData::t_self, tbm_add_tuples(), and IndexScanDescData::xs_ctup.
{
IndexScanDesc scan = (IndexScanDesc) PG_GETARG_POINTER(0);
TIDBitmap *tbm = (TIDBitmap *) PG_GETARG_POINTER(1);
BTScanOpaque so = (BTScanOpaque) scan->opaque;
int64 ntids = 0;
ItemPointer heapTid;
/*
* If we have any array keys, initialize them.
*/
if (so->numArrayKeys)
{
/* punt if we have any unsatisfiable array keys */
if (so->numArrayKeys < 0)
PG_RETURN_INT64(ntids);
_bt_start_array_keys(scan, ForwardScanDirection);
}
/* This loop handles advancing to the next array elements, if any */
do
{
/* Fetch the first page & tuple */
if (_bt_first(scan, ForwardScanDirection))
{
/* Save tuple ID, and continue scanning */
heapTid = &scan->xs_ctup.t_self;
tbm_add_tuples(tbm, heapTid, 1, false);
ntids++;
for (;;)
{
/*
* Advance to next tuple within page. This is the same as the
* easy case in _bt_next().
*/
if (++so->currPos.itemIndex > so->currPos.lastItem)
{
/* let _bt_next do the heavy lifting */
if (!_bt_next(scan, ForwardScanDirection))
break;
}
/* Save tuple ID, and continue scanning */
heapTid = &so->currPos.items[so->currPos.itemIndex].heapTid;
tbm_add_tuples(tbm, heapTid, 1, false);
ntids++;
}
}
/* Now see if we have more array keys to deal with */
} while (so->numArrayKeys && _bt_advance_array_keys(scan, ForwardScanDirection));
PG_RETURN_INT64(ntids);
}
| Datum btgettuple | ( | PG_FUNCTION_ARGS | ) |
Definition at line 270 of file nbtree.c.
References _bt_advance_array_keys(), _bt_first(), _bt_next(), _bt_start_array_keys(), BTScanPosIsValid, BTScanOpaqueData::currPos, BTScanPosData::itemIndex, IndexScanDescData::kill_prior_tuple, BTScanOpaqueData::killedItems, MaxIndexTuplesPerPage, NULL, BTScanOpaqueData::numArrayKeys, BTScanOpaqueData::numKilled, IndexScanDescData::opaque, palloc(), PG_GETARG_INT32, PG_GETARG_POINTER, PG_RETURN_BOOL, and IndexScanDescData::xs_recheck.
{
IndexScanDesc scan = (IndexScanDesc) PG_GETARG_POINTER(0);
ScanDirection dir = (ScanDirection) PG_GETARG_INT32(1);
BTScanOpaque so = (BTScanOpaque) scan->opaque;
bool res;
/* btree indexes are never lossy */
scan->xs_recheck = false;
/*
* If we have any array keys, initialize them during first call for a
* scan. We can't do this in btrescan because we don't know the scan
* direction at that time.
*/
if (so->numArrayKeys && !BTScanPosIsValid(so->currPos))
{
/* punt if we have any unsatisfiable array keys */
if (so->numArrayKeys < 0)
PG_RETURN_BOOL(false);
_bt_start_array_keys(scan, dir);
}
/* This loop handles advancing to the next array elements, if any */
do
{
/*
* If we've already initialized this scan, we can just advance it in
* the appropriate direction. If we haven't done so yet, we call
* _bt_first() to get the first item in the scan.
*/
if (!BTScanPosIsValid(so->currPos))
res = _bt_first(scan, dir);
else
{
/*
* Check to see if we should kill the previously-fetched tuple.
*/
if (scan->kill_prior_tuple)
{
/*
* Yes, remember it for later. (We'll deal with all such
* tuples at once right before leaving the index page.) The
* test for numKilled overrun is not just paranoia: if the
* caller reverses direction in the indexscan then the same
* item might get entered multiple times. It's not worth
* trying to optimize that, so we don't detect it, but instead
* just forget any excess entries.
*/
if (so->killedItems == NULL)
so->killedItems = (int *)
palloc(MaxIndexTuplesPerPage * sizeof(int));
if (so->numKilled < MaxIndexTuplesPerPage)
so->killedItems[so->numKilled++] = so->currPos.itemIndex;
}
/*
* Now continue the scan.
*/
res = _bt_next(scan, dir);
}
/* If we have a tuple, return it ... */
if (res)
break;
/* ... otherwise see if we have more array keys to deal with */
} while (so->numArrayKeys && _bt_advance_array_keys(scan, dir));
PG_RETURN_BOOL(res);
}
| Datum btinsert | ( | PG_FUNCTION_ARGS | ) |
Definition at line 244 of file nbtree.c.
References _bt_doinsert(), index_form_tuple(), pfree(), PG_GETARG_INT32, PG_GETARG_POINTER, PG_RETURN_BOOL, RelationGetDescr, IndexTupleData::t_tid, and values.
{
Relation rel = (Relation) PG_GETARG_POINTER(0);
Datum *values = (Datum *) PG_GETARG_POINTER(1);
bool *isnull = (bool *) PG_GETARG_POINTER(2);
ItemPointer ht_ctid = (ItemPointer) PG_GETARG_POINTER(3);
Relation heapRel = (Relation) PG_GETARG_POINTER(4);
IndexUniqueCheck checkUnique = (IndexUniqueCheck) PG_GETARG_INT32(5);
bool result;
IndexTuple itup;
/* generate an index tuple */
itup = index_form_tuple(RelationGetDescr(rel), values, isnull);
itup->t_tid = *ht_ctid;
result = _bt_doinsert(rel, itup, checkUnique, heapRel);
pfree(itup);
PG_RETURN_BOOL(result);
}
| Datum btmarkpos | ( | PG_FUNCTION_ARGS | ) |
Definition at line 565 of file nbtree.c.
References _bt_mark_array_keys(), BTScanPosIsValid, BTScanPosData::buf, BTScanOpaqueData::currPos, BTScanPosData::itemIndex, BTScanOpaqueData::markItemIndex, BTScanOpaqueData::markPos, BTScanOpaqueData::numArrayKeys, IndexScanDescData::opaque, PG_GETARG_POINTER, PG_RETURN_VOID, and ReleaseBuffer().
{
IndexScanDesc scan = (IndexScanDesc) PG_GETARG_POINTER(0);
BTScanOpaque so = (BTScanOpaque) scan->opaque;
/* we aren't holding any read locks, but gotta drop the pin */
if (BTScanPosIsValid(so->markPos))
{
ReleaseBuffer(so->markPos.buf);
so->markPos.buf = InvalidBuffer;
}
/*
* Just record the current itemIndex. If we later step to next page
* before releasing the marked position, _bt_steppage makes a full copy of
* the currPos struct in markPos. If (as often happens) the mark is moved
* before we leave the page, we don't have to do that work.
*/
if (BTScanPosIsValid(so->currPos))
so->markItemIndex = so->currPos.itemIndex;
else
so->markItemIndex = -1;
/* Also record the current positions of any array keys */
if (so->numArrayKeys)
_bt_mark_array_keys(scan);
PG_RETURN_VOID();
}
| Datum btrescan | ( | PG_FUNCTION_ARGS | ) |
Definition at line 456 of file nbtree.c.
References _bt_killitems(), _bt_preprocess_array_keys(), BTScanPosIsValid, BTScanPosData::buf, BTScanOpaqueData::currPos, BTScanOpaqueData::currTuples, IndexScanDescData::keyData, BTScanOpaqueData::markItemIndex, BTScanOpaqueData::markPos, BTScanOpaqueData::markTuples, memmove, NULL, BTScanOpaqueData::numberOfKeys, IndexScanDescData::numberOfKeys, BTScanOpaqueData::numKilled, IndexScanDescData::opaque, palloc(), PG_GETARG_POINTER, PG_RETURN_VOID, ReleaseBuffer(), and IndexScanDescData::xs_want_itup.
{
IndexScanDesc scan = (IndexScanDesc) PG_GETARG_POINTER(0);
ScanKey scankey = (ScanKey) PG_GETARG_POINTER(1);
/* remaining arguments are ignored */
BTScanOpaque so = (BTScanOpaque) scan->opaque;
/* we aren't holding any read locks, but gotta drop the pins */
if (BTScanPosIsValid(so->currPos))
{
/* Before leaving current page, deal with any killed items */
if (so->numKilled > 0)
_bt_killitems(scan, false);
ReleaseBuffer(so->currPos.buf);
so->currPos.buf = InvalidBuffer;
}
if (BTScanPosIsValid(so->markPos))
{
ReleaseBuffer(so->markPos.buf);
so->markPos.buf = InvalidBuffer;
}
so->markItemIndex = -1;
/*
* Allocate tuple workspace arrays, if needed for an index-only scan and
* not already done in a previous rescan call. To save on palloc
* overhead, both workspaces are allocated as one palloc block; only this
* function and btendscan know that.
*
* NOTE: this data structure also makes it safe to return data from a
* "name" column, even though btree name_ops uses an underlying storage
* datatype of cstring. The risk there is that "name" is supposed to be
* padded to NAMEDATALEN, but the actual index tuple is probably shorter.
* However, since we only return data out of tuples sitting in the
* currTuples array, a fetch of NAMEDATALEN bytes can at worst pull some
* data out of the markTuples array --- running off the end of memory for
* a SIGSEGV is not possible. Yeah, this is ugly as sin, but it beats
* adding special-case treatment for name_ops elsewhere.
*/
if (scan->xs_want_itup && so->currTuples == NULL)
{
so->currTuples = (char *) palloc(BLCKSZ * 2);
so->markTuples = so->currTuples + BLCKSZ;
}
/*
* Reset the scan keys. Note that keys ordering stuff moved to _bt_first.
* - vadim 05/05/97
*/
if (scankey && scan->numberOfKeys > 0)
memmove(scan->keyData,
scankey,
scan->numberOfKeys * sizeof(ScanKeyData));
so->numberOfKeys = 0; /* until _bt_preprocess_keys sets it */
/* If any keys are SK_SEARCHARRAY type, set up array-key info */
_bt_preprocess_array_keys(scan);
PG_RETURN_VOID();
}
| Datum btrestrpos | ( | PG_FUNCTION_ARGS | ) |
Definition at line 599 of file nbtree.c.
References _bt_killitems(), _bt_restore_array_keys(), BTScanPosIsValid, BTScanPosData::buf, BTScanOpaqueData::currPos, BTScanOpaqueData::currTuples, IncrBufferRefCount(), BTScanPosData::itemIndex, BTScanPosData::lastItem, BTScanOpaqueData::markItemIndex, BTScanOpaqueData::markPos, BTScanOpaqueData::markTuples, BTScanPosData::nextTupleOffset, BTScanOpaqueData::numArrayKeys, BTScanOpaqueData::numKilled, offsetof, IndexScanDescData::opaque, PG_GETARG_POINTER, PG_RETURN_VOID, and ReleaseBuffer().
{
IndexScanDesc scan = (IndexScanDesc) PG_GETARG_POINTER(0);
BTScanOpaque so = (BTScanOpaque) scan->opaque;
/* Restore the marked positions of any array keys */
if (so->numArrayKeys)
_bt_restore_array_keys(scan);
if (so->markItemIndex >= 0)
{
/*
* The mark position is on the same page we are currently on. Just
* restore the itemIndex.
*/
so->currPos.itemIndex = so->markItemIndex;
}
else
{
/* we aren't holding any read locks, but gotta drop the pin */
if (BTScanPosIsValid(so->currPos))
{
/* Before leaving current page, deal with any killed items */
if (so->numKilled > 0 &&
so->currPos.buf != so->markPos.buf)
_bt_killitems(scan, false);
ReleaseBuffer(so->currPos.buf);
so->currPos.buf = InvalidBuffer;
}
if (BTScanPosIsValid(so->markPos))
{
/* bump pin on mark buffer for assignment to current buffer */
IncrBufferRefCount(so->markPos.buf);
memcpy(&so->currPos, &so->markPos,
offsetof(BTScanPosData, items[1]) +
so->markPos.lastItem * sizeof(BTScanPosItem));
if (so->currTuples)
memcpy(so->currTuples, so->markTuples,
so->markPos.nextTupleOffset);
}
}
PG_RETURN_VOID();
}
| Datum btvacuumcleanup | ( | PG_FUNCTION_ARGS | ) |
Definition at line 686 of file nbtree.c.
References IndexVacuumInfo::analyze_only, btvacuumscan(), IndexVacuumInfo::estimated_count, IndexVacuumInfo::index, IndexFreeSpaceMapVacuum(), NULL, IndexVacuumInfo::num_heap_tuples, IndexBulkDeleteResult::num_index_tuples, palloc0(), PG_GETARG_POINTER, and PG_RETURN_POINTER.
{
IndexVacuumInfo *info = (IndexVacuumInfo *) PG_GETARG_POINTER(0);
IndexBulkDeleteResult *stats = (IndexBulkDeleteResult *) PG_GETARG_POINTER(1);
/* No-op in ANALYZE ONLY mode */
if (info->analyze_only)
PG_RETURN_POINTER(stats);
/*
* If btbulkdelete was called, we need not do anything, just return the
* stats from the latest btbulkdelete call. If it wasn't called, we must
* still do a pass over the index, to recycle any newly-recyclable pages
* and to obtain index statistics.
*
* Since we aren't going to actually delete any leaf items, there's no
* need to go through all the vacuum-cycle-ID pushups.
*/
if (stats == NULL)
{
stats = (IndexBulkDeleteResult *) palloc0(sizeof(IndexBulkDeleteResult));
btvacuumscan(info, stats, NULL, NULL, 0);
}
/* Finally, vacuum the FSM */
IndexFreeSpaceMapVacuum(info->index);
/*
* It's quite possible for us to be fooled by concurrent page splits into
* double-counting some index tuples, so disbelieve any total that exceeds
* the underlying heap's count ... if we know that accurately. Otherwise
* this might just make matters worse.
*/
if (!info->estimated_count)
{
if (stats->num_index_tuples > info->num_heap_tuples)
stats->num_index_tuples = info->num_heap_tuples;
}
PG_RETURN_POINTER(stats);
}
| static void btvacuumpage | ( | BTVacState * | vstate, | |
| BlockNumber | blkno, | |||
| BlockNumber | orig_blkno | |||
| ) | [static] |
Definition at line 866 of file nbtree.c.
References _bt_checkpage(), _bt_delitems_vacuum(), _bt_page_recyclable(), _bt_pagedel(), _bt_relbuf(), BT_READ, BTP_SPLIT_END, BTPageOpaqueData::btpo_cycleid, BTPageOpaqueData::btpo_flags, BTPageOpaqueData::btpo_next, buf, BUFFER_LOCK_UNLOCK, BufferGetBlockNumber(), BufferGetPage, BTVacState::callback, callback(), BTVacState::callback_state, BTVacState::cycleid, IndexVacuumInfo::index, BTVacState::info, BTVacState::lastBlockVacuumed, BTVacState::lastUsedPage, LockBuffer(), LockBufferForCleanup(), MAIN_FORKNUM, MarkBufferDirtyHint(), MemoryContextReset(), MemoryContextSwitchTo(), NULL, IndexBulkDeleteResult::num_index_tuples, OffsetNumberNext, P_FIRSTDATAKEY, P_IGNORE, P_ISDELETED, P_ISHALFDEAD, P_ISLEAF, P_NONE, P_RIGHTMOST, BTVacState::pagedelcontext, PageGetItem, PageGetItemId, PageGetMaxOffsetNumber, PageGetSpecialPointer, PageIsNew, IndexBulkDeleteResult::pages_deleted, RBM_NORMAL, ReadBufferExtended(), RecordFreeIndexPage(), BTVacState::stats, IndexVacuumInfo::strategy, IndexTupleData::t_tid, BTVacState::totFreePages, IndexBulkDeleteResult::tuples_removed, and vacuum_delay_point().
Referenced by btvacuumscan().
{
IndexVacuumInfo *info = vstate->info;
IndexBulkDeleteResult *stats = vstate->stats;
IndexBulkDeleteCallback callback = vstate->callback;
void *callback_state = vstate->callback_state;
Relation rel = info->index;
bool delete_now;
BlockNumber recurse_to;
Buffer buf;
Page page;
BTPageOpaque opaque;
restart:
delete_now = false;
recurse_to = P_NONE;
/* call vacuum_delay_point while not holding any buffer lock */
vacuum_delay_point();
/*
* We can't use _bt_getbuf() here because it always applies
* _bt_checkpage(), which will barf on an all-zero page. We want to
* recycle all-zero pages, not fail. Also, we want to use a nondefault
* buffer access strategy.
*/
buf = ReadBufferExtended(rel, MAIN_FORKNUM, blkno, RBM_NORMAL,
info->strategy);
LockBuffer(buf, BT_READ);
page = BufferGetPage(buf);
opaque = (BTPageOpaque) PageGetSpecialPointer(page);
if (!PageIsNew(page))
_bt_checkpage(rel, buf);
/*
* If we are recursing, the only case we want to do anything with is a
* live leaf page having the current vacuum cycle ID. Any other state
* implies we already saw the page (eg, deleted it as being empty).
*/
if (blkno != orig_blkno)
{
if (_bt_page_recyclable(page) ||
P_IGNORE(opaque) ||
!P_ISLEAF(opaque) ||
opaque->btpo_cycleid != vstate->cycleid)
{
_bt_relbuf(rel, buf);
return;
}
}
/* If the page is in use, update lastUsedPage */
if (!_bt_page_recyclable(page) && vstate->lastUsedPage < blkno)
vstate->lastUsedPage = blkno;
/* Page is valid, see what to do with it */
if (_bt_page_recyclable(page))
{
/* Okay to recycle this page */
RecordFreeIndexPage(rel, blkno);
vstate->totFreePages++;
stats->pages_deleted++;
}
else if (P_ISDELETED(opaque))
{
/* Already deleted, but can't recycle yet */
stats->pages_deleted++;
}
else if (P_ISHALFDEAD(opaque))
{
/* Half-dead, try to delete */
delete_now = true;
}
else if (P_ISLEAF(opaque))
{
OffsetNumber deletable[MaxOffsetNumber];
int ndeletable;
OffsetNumber offnum,
minoff,
maxoff;
/*
* Trade in the initial read lock for a super-exclusive write lock on
* this page. We must get such a lock on every leaf page over the
* course of the vacuum scan, whether or not it actually contains any
* deletable tuples --- see nbtree/README.
*/
LockBuffer(buf, BUFFER_LOCK_UNLOCK);
LockBufferForCleanup(buf);
/*
* Check whether we need to recurse back to earlier pages. What we
* are concerned about is a page split that happened since we started
* the vacuum scan. If the split moved some tuples to a lower page
* then we might have missed 'em. If so, set up for tail recursion.
* (Must do this before possibly clearing btpo_cycleid below!)
*/
if (vstate->cycleid != 0 &&
opaque->btpo_cycleid == vstate->cycleid &&
!(opaque->btpo_flags & BTP_SPLIT_END) &&
!P_RIGHTMOST(opaque) &&
opaque->btpo_next < orig_blkno)
recurse_to = opaque->btpo_next;
/*
* Scan over all items to see which ones need deleted according to the
* callback function.
*/
ndeletable = 0;
minoff = P_FIRSTDATAKEY(opaque);
maxoff = PageGetMaxOffsetNumber(page);
if (callback)
{
for (offnum = minoff;
offnum <= maxoff;
offnum = OffsetNumberNext(offnum))
{
IndexTuple itup;
ItemPointer htup;
itup = (IndexTuple) PageGetItem(page,
PageGetItemId(page, offnum));
htup = &(itup->t_tid);
/*
* During Hot Standby we currently assume that
* XLOG_BTREE_VACUUM records do not produce conflicts. That is
* only true as long as the callback function depends only
* upon whether the index tuple refers to heap tuples removed
* in the initial heap scan. When vacuum starts it derives a
* value of OldestXmin. Backends taking later snapshots could
* have a RecentGlobalXmin with a later xid than the vacuum's
* OldestXmin, so it is possible that row versions deleted
* after OldestXmin could be marked as killed by other
* backends. The callback function *could* look at the index
* tuple state in isolation and decide to delete the index
* tuple, though currently it does not. If it ever did, we
* would need to reconsider whether XLOG_BTREE_VACUUM records
* should cause conflicts. If they did cause conflicts they
* would be fairly harsh conflicts, since we haven't yet
* worked out a way to pass a useful value for
* latestRemovedXid on the XLOG_BTREE_VACUUM records. This
* applies to *any* type of index that marks index tuples as
* killed.
*/
if (callback(htup, callback_state))
deletable[ndeletable++] = offnum;
}
}
/*
* Apply any needed deletes. We issue just one _bt_delitems_vacuum()
* call per page, so as to minimize WAL traffic.
*/
if (ndeletable > 0)
{
BlockNumber lastBlockVacuumed = BufferGetBlockNumber(buf);
_bt_delitems_vacuum(rel, buf, deletable, ndeletable,
vstate->lastBlockVacuumed);
/*
* Keep track of the block number of the lastBlockVacuumed, so we
* can scan those blocks as well during WAL replay. This then
* provides concurrency protection and allows btrees to be used
* while in recovery.
*/
if (lastBlockVacuumed > vstate->lastBlockVacuumed)
vstate->lastBlockVacuumed = lastBlockVacuumed;
stats->tuples_removed += ndeletable;
/* must recompute maxoff */
maxoff = PageGetMaxOffsetNumber(page);
}
else
{
/*
* If the page has been split during this vacuum cycle, it seems
* worth expending a write to clear btpo_cycleid even if we don't
* have any deletions to do. (If we do, _bt_delitems_vacuum takes
* care of this.) This ensures we won't process the page again.
*
* We treat this like a hint-bit update because there's no need to
* WAL-log it.
*/
if (vstate->cycleid != 0 &&
opaque->btpo_cycleid == vstate->cycleid)
{
opaque->btpo_cycleid = 0;
MarkBufferDirtyHint(buf);
}
}
/*
* If it's now empty, try to delete; else count the live tuples. We
* don't delete when recursing, though, to avoid putting entries into
* freePages out-of-order (doesn't seem worth any extra code to handle
* the case).
*/
if (minoff > maxoff)
delete_now = (blkno == orig_blkno);
else
stats->num_index_tuples += maxoff - minoff + 1;
}
if (delete_now)
{
MemoryContext oldcontext;
int ndel;
/* Run pagedel in a temp context to avoid memory leakage */
MemoryContextReset(vstate->pagedelcontext);
oldcontext = MemoryContextSwitchTo(vstate->pagedelcontext);
ndel = _bt_pagedel(rel, buf, NULL);
/* count only this page, else may double-count parent */
if (ndel)
stats->pages_deleted++;
MemoryContextSwitchTo(oldcontext);
/* pagedel released buffer, so we shouldn't */
}
else
_bt_relbuf(rel, buf);
/*
* This is really tail recursion, but if the compiler is too stupid to
* optimize it as such, we'd eat an uncomfortably large amount of stack
* space per recursion level (due to the deletable[] array). A failure is
* improbable since the number of levels isn't likely to be large ... but
* just in case, let's hand-optimize into a loop.
*/
if (recurse_to != P_NONE)
{
blkno = recurse_to;
goto restart;
}
}
| static void btvacuumscan | ( | IndexVacuumInfo * | info, | |
| IndexBulkDeleteResult * | stats, | |||
| IndexBulkDeleteCallback | callback, | |||
| void * | callback_state, | |||
| BTCycleId | cycleid | |||
| ) | [static] |
Definition at line 741 of file nbtree.c.
References _bt_delitems_vacuum(), _bt_relbuf(), ALLOCSET_DEFAULT_INITSIZE, ALLOCSET_DEFAULT_MAXSIZE, ALLOCSET_DEFAULT_MINSIZE, AllocSetContextCreate(), BTREE_METAPAGE, btvacuumpage(), buf, BTVacState::callback, BTVacState::callback_state, CurrentMemoryContext, BTVacState::cycleid, IndexBulkDeleteResult::estimated_count, ExclusiveLock, IndexVacuumInfo::index, BTVacState::info, BTVacState::lastBlockVacuumed, BTVacState::lastUsedPage, LockBufferForCleanup(), LockRelationForExtension(), MAIN_FORKNUM, MemoryContextDelete(), NULL, IndexBulkDeleteResult::num_index_tuples, IndexBulkDeleteResult::num_pages, BTVacState::pagedelcontext, IndexBulkDeleteResult::pages_deleted, IndexBulkDeleteResult::pages_free, RBM_NORMAL, ReadBufferExtended(), RELATION_IS_LOCAL, RelationGetNumberOfBlocks, BTVacState::stats, IndexVacuumInfo::strategy, BTVacState::totFreePages, UnlockRelationForExtension(), and XLogStandbyInfoActive.
Referenced by btbulkdelete(), and btvacuumcleanup().
{
Relation rel = info->index;
BTVacState vstate;
BlockNumber num_pages;
BlockNumber blkno;
bool needLock;
/*
* Reset counts that will be incremented during the scan; needed in case
* of multiple scans during a single VACUUM command
*/
stats->estimated_count = false;
stats->num_index_tuples = 0;
stats->pages_deleted = 0;
/* Set up info to pass down to btvacuumpage */
vstate.info = info;
vstate.stats = stats;
vstate.callback = callback;
vstate.callback_state = callback_state;
vstate.cycleid = cycleid;
vstate.lastBlockVacuumed = BTREE_METAPAGE; /* Initialise at first block */
vstate.lastUsedPage = BTREE_METAPAGE;
vstate.totFreePages = 0;
/* Create a temporary memory context to run _bt_pagedel in */
vstate.pagedelcontext = AllocSetContextCreate(CurrentMemoryContext,
"_bt_pagedel",
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
/*
* The outer loop iterates over all index pages except the metapage, in
* physical order (we hope the kernel will cooperate in providing
* read-ahead for speed). It is critical that we visit all leaf pages,
* including ones added after we start the scan, else we might fail to
* delete some deletable tuples. Hence, we must repeatedly check the
* relation length. We must acquire the relation-extension lock while
* doing so to avoid a race condition: if someone else is extending the
* relation, there is a window where bufmgr/smgr have created a new
* all-zero page but it hasn't yet been write-locked by _bt_getbuf(). If
* we manage to scan such a page here, we'll improperly assume it can be
* recycled. Taking the lock synchronizes things enough to prevent a
* problem: either num_pages won't include the new page, or _bt_getbuf
* already has write lock on the buffer and it will be fully initialized
* before we can examine it. (See also vacuumlazy.c, which has the same
* issue.) Also, we need not worry if a page is added immediately after
* we look; the page splitting code already has write-lock on the left
* page before it adds a right page, so we must already have processed any
* tuples due to be moved into such a page.
*
* We can skip locking for new or temp relations, however, since no one
* else could be accessing them.
*/
needLock = !RELATION_IS_LOCAL(rel);
blkno = BTREE_METAPAGE + 1;
for (;;)
{
/* Get the current relation length */
if (needLock)
LockRelationForExtension(rel, ExclusiveLock);
num_pages = RelationGetNumberOfBlocks(rel);
if (needLock)
UnlockRelationForExtension(rel, ExclusiveLock);
/* Quit if we've scanned the whole relation */
if (blkno >= num_pages)
break;
/* Iterate over pages, then loop back to recheck length */
for (; blkno < num_pages; blkno++)
{
btvacuumpage(&vstate, blkno, blkno);
}
}
/*
* InHotStandby we need to scan right up to the end of the index for
* correct locking, so we may need to write a WAL record for the final
* block in the index if it was not vacuumed. It's possible that VACUUMing
* has actually removed zeroed pages at the end of the index so we need to
* take care to issue the record for last actual block and not for the
* last block that was scanned. Ignore empty indexes.
*/
if (XLogStandbyInfoActive() &&
num_pages > 1 && vstate.lastBlockVacuumed < (num_pages - 1))
{
Buffer buf;
/*
* We can't use _bt_getbuf() here because it always applies
* _bt_checkpage(), which will barf on an all-zero page. We want to
* recycle all-zero pages, not fail. Also, we want to use a
* nondefault buffer access strategy.
*/
buf = ReadBufferExtended(rel, MAIN_FORKNUM, num_pages - 1, RBM_NORMAL,
info->strategy);
LockBufferForCleanup(buf);
_bt_delitems_vacuum(rel, buf, NULL, 0, vstate.lastBlockVacuumed);
_bt_relbuf(rel, buf);
}
MemoryContextDelete(vstate.pagedelcontext);
/* update statistics */
stats->num_pages = num_pages;
stats->pages_free = vstate.totFreePages;
}
1.7.1