/*
* Add new bloom tuple to the page. Returns true if new tuple was successfully
* added to the page. Returns false if it doesn't fit on the page.
*/
bool
BloomPageAddItem(BloomState *state, Page page, BloomTuple *tuple)
{
BloomTuple *itup;
BloomPageOpaque opaque;
Pointer ptr;
/* We shouldn't be pointed to an invalid page */
Assert(!PageIsNew(page) && !BloomPageIsDeleted(page));
/* Does new tuple fit on the page? */
if (BloomPageGetFreeSpace(state, page) < state->sizeOfBloomTuple)
return false;
/* Copy new tuple to the end of page */
opaque = BloomPageGetOpaque(page);
itup = BloomPageGetTuple(state, page, opaque->maxoff + 1);
memcpy((Pointer) itup, (Pointer) tuple, state->sizeOfBloomTuple);
/* Adjust maxoff and pd_lower */
opaque->maxoff++;
ptr = (Pointer) BloomPageGetTuple(state, page, opaque->maxoff + 1);
((PageHeader) page)->pd_lower = ptr - page;
/* Assert we didn't overrun available space */
Assert(((PageHeader) page)->pd_lower <= ((PageHeader) page)->pd_upper);
return true;
}
/*
* Post-VACUUM cleanup.
*
* Result: a palloc'd struct containing statistical info for VACUUM displays.
*/
IndexBulkDeleteResult *
blvacuumcleanup(IndexVacuumInfo *info, IndexBulkDeleteResult *stats)
{
Relation index = info->index;
BlockNumber npages,
blkno;
BlockNumber totFreePages;
if (info->analyze_only)
return stats;
if (stats == NULL)
stats = (IndexBulkDeleteResult *) palloc0(sizeof(IndexBulkDeleteResult));
/*
* Iterate over the pages: insert deleted pages into FSM and collect
* statistics.
*/
npages = RelationGetNumberOfBlocks(index);
totFreePages = 0;
for (blkno = BLOOM_HEAD_BLKNO; blkno < npages; blkno++)
{
Buffer buffer;
Page page;
vacuum_delay_point();
buffer = ReadBufferExtended(index, MAIN_FORKNUM, blkno,
RBM_NORMAL, info->strategy);
LockBuffer(buffer, BUFFER_LOCK_SHARE);
page = BufferGetPage(buffer, NULL, NULL, BGP_NO_SNAPSHOT_TEST);
if (BloomPageIsDeleted(page))
{
RecordFreeIndexPage(index, blkno);
totFreePages++;
}
else
{
stats->num_index_tuples += BloomPageGetMaxOffset(page);
stats->estimated_count += BloomPageGetMaxOffset(page);
}
UnlockReleaseBuffer(buffer);
}
IndexFreeSpaceMapVacuum(info->index);
stats->pages_free = totFreePages;
stats->num_pages = RelationGetNumberOfBlocks(index);
return stats;
}
/*
* Allocate a new page (either by recycling, or by extending the index file)
* The returned buffer is already pinned and exclusive-locked
* Caller is responsible for initializing the page by calling BloomInitBuffer
*/
Buffer
BloomNewBuffer(Relation index)
{
Buffer buffer;
bool needLock;
/* First, try to get a page from FSM */
for (;;)
{
BlockNumber blkno = GetFreeIndexPage(index);
if (blkno == InvalidBlockNumber)
break;
buffer = ReadBuffer(index, blkno);
/*
* We have to guard against the possibility that someone else already
* recycled this page; the buffer may be locked if so.
*/
if (ConditionalLockBuffer(buffer))
{
Page page = BufferGetPage(buffer);
if (PageIsNew(page))
return buffer; /* OK to use, if never initialized */
if (BloomPageIsDeleted(page))
return buffer; /* OK to use */
LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
}
/* Can't use it, so release buffer and try again */
ReleaseBuffer(buffer);
}
/* Must extend the file */
needLock = !RELATION_IS_LOCAL(index);
if (needLock)
LockRelationForExtension(index, ExclusiveLock);
buffer = ReadBuffer(index, P_NEW);
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
if (needLock)
UnlockRelationForExtension(index, ExclusiveLock);
return buffer;
}
/*
* Insert all matching tuples into to a bitmap.
*/
int64
blgetbitmap(IndexScanDesc scan, TIDBitmap *tbm)
{
int64 ntids = 0;
BlockNumber blkno = BLOOM_HEAD_BLKNO,
npages;
int i;
BufferAccessStrategy bas;
BloomScanOpaque so = (BloomScanOpaque) scan->opaque;
if (so->sign == NULL)
{
/* New search: have to calculate search signature */
ScanKey skey = scan->keyData;
so->sign = palloc0(sizeof(SignType) * so->state.opts.bloomLength);
for (i = 0; i < scan->numberOfKeys; i++)
{
/*
* Assume bloom-indexable operators to be strict, so nothing could
* be found for NULL key.
*/
if (skey->sk_flags & SK_ISNULL)
{
pfree(so->sign);
so->sign = NULL;
return 0;
}
/* Add next value to the signature */
signValue(&so->state, so->sign, skey->sk_argument,
skey->sk_attno - 1);
skey++;
}
}
/*
* We're going to read the whole index. This is why we use appropriate
* buffer access strategy.
*/
bas = GetAccessStrategy(BAS_BULKREAD);
npages = RelationGetNumberOfBlocks(scan->indexRelation);
for (blkno = BLOOM_HEAD_BLKNO; blkno < npages; blkno++)
{
Buffer buffer;
Page page;
buffer = ReadBufferExtended(scan->indexRelation, MAIN_FORKNUM,
blkno, RBM_NORMAL, bas);
LockBuffer(buffer, BUFFER_LOCK_SHARE);
page = BufferGetPage(buffer);
TestForOldSnapshot(scan->xs_snapshot, scan->indexRelation, page);
if (!BloomPageIsDeleted(page))
{
OffsetNumber offset,
maxOffset = BloomPageGetMaxOffset(page);
for (offset = 1; offset <= maxOffset; offset++)
{
BloomTuple *itup = BloomPageGetTuple(&so->state, page, offset);
bool res = true;
/* Check index signature with scan signature */
for (i = 0; i < so->state.opts.bloomLength; i++)
{
if ((itup->sign[i] & so->sign[i]) != so->sign[i])
{
res = false;
break;
}
}
/* Add matching tuples to bitmap */
if (res)
{
tbm_add_tuples(tbm, &itup->heapPtr, 1, true);
ntids++;
}
}
}
UnlockReleaseBuffer(buffer);
CHECK_FOR_INTERRUPTS();
}
FreeAccessStrategy(bas);
return ntids;
}
/*
* Bulk deletion of all index entries pointing to a set of heap tuples.
* The set of target tuples is specified via a callback routine that tells
* whether any given heap tuple (identified by ItemPointer) is being deleted.
*
* Result: a palloc'd struct containing statistical info for VACUUM displays.
*/
IndexBulkDeleteResult *
blbulkdelete(IndexVacuumInfo *info, IndexBulkDeleteResult *stats,
IndexBulkDeleteCallback callback, void *callback_state)
{
Relation index = info->index;
BlockNumber blkno,
npages;
FreeBlockNumberArray notFullPage;
int countPage = 0;
BloomState state;
Buffer buffer;
Page page;
GenericXLogState *gxlogState;
if (stats == NULL)
stats = (IndexBulkDeleteResult *) palloc0(sizeof(IndexBulkDeleteResult));
initBloomState(&state, index);
/*
* Interate over the pages. We don't care about concurrently added pages,
* they can't contain tuples to delete.
*/
npages = RelationGetNumberOfBlocks(index);
for (blkno = BLOOM_HEAD_BLKNO; blkno < npages; blkno++)
{
BloomTuple *itup,
*itupPtr,
*itupEnd;
buffer = ReadBufferExtended(index, MAIN_FORKNUM, blkno,
RBM_NORMAL, info->strategy);
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
gxlogState = GenericXLogStart(index);
page = GenericXLogRegisterBuffer(gxlogState, buffer, 0);
if (BloomPageIsDeleted(page))
{
UnlockReleaseBuffer(buffer);
GenericXLogAbort(gxlogState);
CHECK_FOR_INTERRUPTS();
continue;
}
/* Iterate over the tuples */
itup = itupPtr = BloomPageGetTuple(&state, page, FirstOffsetNumber);
itupEnd = BloomPageGetTuple(&state, page,
OffsetNumberNext(BloomPageGetMaxOffset(page)));
while (itup < itupEnd)
{
/* Do we have to delete this tuple? */
if (callback(&itup->heapPtr, callback_state))
{
stats->tuples_removed += 1;
BloomPageGetOpaque(page)->maxoff--;
}
else
{
if (itupPtr != itup)
{
/*
* If we already delete something before, we have to move
* this tuple backward.
*/
memmove((Pointer) itupPtr, (Pointer) itup,
state.sizeOfBloomTuple);
}
stats->num_index_tuples++;
itupPtr = BloomPageGetNextTuple(&state, itupPtr);
}
itup = BloomPageGetNextTuple(&state, itup);
}
Assert(itupPtr == BloomPageGetTuple(&state, page,
OffsetNumberNext(BloomPageGetMaxOffset(page))));
/*
* Add page to notFullPage list if we will not mark page as deleted and
* there is a free space on it
*/
if (BloomPageGetMaxOffset(page) != 0 &&
BloomPageGetFreeSpace(&state, page) > state.sizeOfBloomTuple &&
countPage < BloomMetaBlockN)
notFullPage[countPage++] = blkno;
/* Did we delete something? */
if (itupPtr != itup)
{
/* Is it empty page now? */
if (BloomPageGetMaxOffset(page) == 0)
BloomPageSetDeleted(page);
/* Adjust pg_lower */
((PageHeader) page)->pd_lower = (Pointer) itupPtr - page;
/* Finish WAL-logging */
GenericXLogFinish(gxlogState);
}
else
{
/* Didn't change anything: abort WAL-logging */
GenericXLogAbort(gxlogState);
}
UnlockReleaseBuffer(buffer);
CHECK_FOR_INTERRUPTS();
}
if (countPage > 0)
{
BloomMetaPageData *metaData;
buffer = ReadBuffer(index, BLOOM_METAPAGE_BLKNO);
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
gxlogState = GenericXLogStart(index);
page = GenericXLogRegisterBuffer(gxlogState, buffer, 0);
metaData = BloomPageGetMeta(page);
memcpy(metaData->notFullPage, notFullPage, sizeof(BlockNumber) * countPage);
metaData->nStart = 0;
metaData->nEnd = countPage;
GenericXLogFinish(gxlogState);
UnlockReleaseBuffer(buffer);
}
return stats;
}
/*
* Insert new tuple to the bloom index.
*/
bool
blinsert(Relation index, Datum *values, bool *isnull,
ItemPointer ht_ctid, Relation heapRel,
IndexUniqueCheck checkUnique,
IndexInfo *indexInfo)
{
BloomState blstate;
BloomTuple *itup;
MemoryContext oldCtx;
MemoryContext insertCtx;
BloomMetaPageData *metaData;
Buffer buffer,
metaBuffer;
Page page,
metaPage;
BlockNumber blkno = InvalidBlockNumber;
OffsetNumber nStart;
GenericXLogState *state;
insertCtx = AllocSetContextCreate(CurrentMemoryContext,
"Bloom insert temporary context",
ALLOCSET_DEFAULT_SIZES);
oldCtx = MemoryContextSwitchTo(insertCtx);
initBloomState(&blstate, index);
itup = BloomFormTuple(&blstate, ht_ctid, values, isnull);
/*
* At first, try to insert new tuple to the first page in notFullPage
* array. If successful, we don't need to modify the meta page.
*/
metaBuffer = ReadBuffer(index, BLOOM_METAPAGE_BLKNO);
LockBuffer(metaBuffer, BUFFER_LOCK_SHARE);
metaData = BloomPageGetMeta(BufferGetPage(metaBuffer));
if (metaData->nEnd > metaData->nStart)
{
Page page;
blkno = metaData->notFullPage[metaData->nStart];
Assert(blkno != InvalidBlockNumber);
/* Don't hold metabuffer lock while doing insert */
LockBuffer(metaBuffer, BUFFER_LOCK_UNLOCK);
buffer = ReadBuffer(index, blkno);
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
state = GenericXLogStart(index);
page = GenericXLogRegisterBuffer(state, buffer, 0);
/*
* We might have found a page that was recently deleted by VACUUM. If
* so, we can reuse it, but we must reinitialize it.
*/
if (PageIsNew(page) || BloomPageIsDeleted(page))
BloomInitPage(page, 0);
if (BloomPageAddItem(&blstate, page, itup))
{
/* Success! Apply the change, clean up, and exit */
GenericXLogFinish(state);
UnlockReleaseBuffer(buffer);
ReleaseBuffer(metaBuffer);
MemoryContextSwitchTo(oldCtx);
MemoryContextDelete(insertCtx);
return false;
}
/* Didn't fit, must try other pages */
GenericXLogAbort(state);
UnlockReleaseBuffer(buffer);
}
else
{
/* No entries in notFullPage */
LockBuffer(metaBuffer, BUFFER_LOCK_UNLOCK);
}
/*
* Try other pages in notFullPage array. We will have to change nStart in
* metapage. Thus, grab exclusive lock on metapage.
*/
LockBuffer(metaBuffer, BUFFER_LOCK_EXCLUSIVE);
/* nStart might have changed while we didn't have lock */
nStart = metaData->nStart;
/* Skip first page if we already tried it above */
if (nStart < metaData->nEnd &&
blkno == metaData->notFullPage[nStart])
nStart++;
/*
* This loop iterates for each page we try from the notFullPage array, and
* will also initialize a GenericXLogState for the fallback case of having
* to allocate a new page.
*/
for (;;)
{
state = GenericXLogStart(index);
/* get modifiable copy of metapage */
metaPage = GenericXLogRegisterBuffer(state, metaBuffer, 0);
metaData = BloomPageGetMeta(metaPage);
if (nStart >= metaData->nEnd)
break; /* no more entries in notFullPage array */
blkno = metaData->notFullPage[nStart];
Assert(blkno != InvalidBlockNumber);
buffer = ReadBuffer(index, blkno);
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
page = GenericXLogRegisterBuffer(state, buffer, 0);
/* Basically same logic as above */
if (PageIsNew(page) || BloomPageIsDeleted(page))
BloomInitPage(page, 0);
if (BloomPageAddItem(&blstate, page, itup))
{
/* Success! Apply the changes, clean up, and exit */
metaData->nStart = nStart;
GenericXLogFinish(state);
UnlockReleaseBuffer(buffer);
UnlockReleaseBuffer(metaBuffer);
MemoryContextSwitchTo(oldCtx);
MemoryContextDelete(insertCtx);
return false;
}
/* Didn't fit, must try other pages */
GenericXLogAbort(state);
UnlockReleaseBuffer(buffer);
nStart++;
}
/*
* Didn't find place to insert in notFullPage array. Allocate new page.
* (XXX is it good to do this while holding ex-lock on the metapage??)
*/
buffer = BloomNewBuffer(index);
page = GenericXLogRegisterBuffer(state, buffer, GENERIC_XLOG_FULL_IMAGE);
BloomInitPage(page, 0);
if (!BloomPageAddItem(&blstate, page, itup))
{
/* We shouldn't be here since we're inserting to an empty page */
elog(ERROR, "could not add new bloom tuple to empty page");
}
/* Reset notFullPage array to contain just this new page */
metaData->nStart = 0;
metaData->nEnd = 1;
metaData->notFullPage[0] = BufferGetBlockNumber(buffer);
/* Apply the changes, clean up, and exit */
GenericXLogFinish(state);
UnlockReleaseBuffer(buffer);
UnlockReleaseBuffer(metaBuffer);
MemoryContextSwitchTo(oldCtx);
MemoryContextDelete(insertCtx);
return false;
}
/*
* Bulk deletion of all index entries pointing to a set of heap tuples.
* The set of target tuples is specified via a callback routine that tells
* whether any given heap tuple (identified by ItemPointer) is being deleted.
*
* Result: a palloc'd struct containing statistical info for VACUUM displays.
*/
IndexBulkDeleteResult *
blbulkdelete(IndexVacuumInfo *info, IndexBulkDeleteResult *stats,
IndexBulkDeleteCallback callback, void *callback_state)
{
Relation index = info->index;
BlockNumber blkno,
npages;
FreeBlockNumberArray notFullPage;
int countPage = 0;
BloomState state;
Buffer buffer;
Page page;
BloomMetaPageData *metaData;
GenericXLogState *gxlogState;
if (stats == NULL)
stats = (IndexBulkDeleteResult *) palloc0(sizeof(IndexBulkDeleteResult));
initBloomState(&state, index);
/*
* Interate over the pages. We don't care about concurrently added pages,
* they can't contain tuples to delete.
*/
npages = RelationGetNumberOfBlocks(index);
for (blkno = BLOOM_HEAD_BLKNO; blkno < npages; blkno++)
{
BloomTuple *itup,
*itupPtr,
*itupEnd;
vacuum_delay_point();
buffer = ReadBufferExtended(index, MAIN_FORKNUM, blkno,
RBM_NORMAL, info->strategy);
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
gxlogState = GenericXLogStart(index);
page = GenericXLogRegisterBuffer(gxlogState, buffer, 0);
/* Ignore empty/deleted pages until blvacuumcleanup() */
if (PageIsNew(page) || BloomPageIsDeleted(page))
{
UnlockReleaseBuffer(buffer);
GenericXLogAbort(gxlogState);
continue;
}
/*
* Iterate over the tuples. itup points to current tuple being
* scanned, itupPtr points to where to save next non-deleted tuple.
*/
itup = itupPtr = BloomPageGetTuple(&state, page, FirstOffsetNumber);
itupEnd = BloomPageGetTuple(&state, page,
OffsetNumberNext(BloomPageGetMaxOffset(page)));
while (itup < itupEnd)
{
/* Do we have to delete this tuple? */
if (callback(&itup->heapPtr, callback_state))
{
/* Yes; adjust count of tuples that will be left on page */
BloomPageGetOpaque(page)->maxoff--;
stats->tuples_removed += 1;
}
else
{
/* No; copy it to itupPtr++, but skip copy if not needed */
if (itupPtr != itup)
memmove((Pointer) itupPtr, (Pointer) itup,
state.sizeOfBloomTuple);
itupPtr = BloomPageGetNextTuple(&state, itupPtr);
}
itup = BloomPageGetNextTuple(&state, itup);
}
/* Assert that we counted correctly */
Assert(itupPtr == BloomPageGetTuple(&state, page,
OffsetNumberNext(BloomPageGetMaxOffset(page))));
/*
* Add page to new notFullPage list if we will not mark page as
* deleted and there is free space on it
*/
if (BloomPageGetMaxOffset(page) != 0 &&
BloomPageGetFreeSpace(&state, page) >= state.sizeOfBloomTuple &&
countPage < BloomMetaBlockN)
notFullPage[countPage++] = blkno;
/* Did we delete something? */
if (itupPtr != itup)
{
/* Is it empty page now? */
if (BloomPageGetMaxOffset(page) == 0)
BloomPageSetDeleted(page);
/* Adjust pg_lower */
((PageHeader) page)->pd_lower = (Pointer) itupPtr - page;
/* Finish WAL-logging */
GenericXLogFinish(gxlogState);
}
else
{
/* Didn't change anything: abort WAL-logging */
GenericXLogAbort(gxlogState);
}
UnlockReleaseBuffer(buffer);
}
/*
* Update the metapage's notFullPage list with whatever we found. Our
* info could already be out of date at this point, but blinsert() will
* cope if so.
*/
buffer = ReadBuffer(index, BLOOM_METAPAGE_BLKNO);
LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
gxlogState = GenericXLogStart(index);
page = GenericXLogRegisterBuffer(gxlogState, buffer, 0);
metaData = BloomPageGetMeta(page);
memcpy(metaData->notFullPage, notFullPage, sizeof(BlockNumber) * countPage);
metaData->nStart = 0;
metaData->nEnd = countPage;
GenericXLogFinish(gxlogState);
UnlockReleaseBuffer(buffer);
return stats;
}