postgresql/contrib/bloom/blinsert.c
Tom Lane abaffa9075 Fix contrib/bloom to work for unlogged indexes.
blbuildempty did not do even approximately the right thing: it tried
to add a metapage to the relation's regular data fork, which already
has one at that point.  It should look like the ambuildempty methods
for all the standard index types, ie, initialize a metapage image in
some transient storage and then write it directly to the init fork.
To support that, refactor BloomInitMetapage into two functions.

In passing, fix BloomInitMetapage so it doesn't leave the rd_options
field of the index's relcache entry pointing at transient storage.
I'm not sure this had any visible consequence, since nothing much
else is likely to look at a bloom index's rd_options, but it's
certainly poor practice.

Per bug #14155 from Zhou Digoal.

Report: <20160524144146.22598.42558@wrigleys.postgresql.org>
2016-05-24 21:04:35 -04:00

347 lines
9.0 KiB
C

/*-------------------------------------------------------------------------
*
* blinsert.c
* Bloom index build and insert functions.
*
* Copyright (c) 2016, PostgreSQL Global Development Group
*
* IDENTIFICATION
* contrib/bloom/blinsert.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/genam.h"
#include "access/generic_xlog.h"
#include "catalog/index.h"
#include "miscadmin.h"
#include "storage/bufmgr.h"
#include "storage/indexfsm.h"
#include "storage/smgr.h"
#include "utils/memutils.h"
#include "utils/rel.h"
#include "bloom.h"
PG_MODULE_MAGIC;
/*
* State of bloom index build. We accumulate one page data here before
* flushing it to buffer manager.
*/
typedef struct
{
BloomState blstate; /* bloom index state */
MemoryContext tmpCtx; /* temporary memory context reset after
* each tuple */
char data[BLCKSZ]; /* cached page */
int64 count; /* number of tuples in cached page */
} BloomBuildState;
/*
* Flush page cached in BloomBuildState.
*/
static void
flushCachedPage(Relation index, BloomBuildState *buildstate)
{
Page page;
Buffer buffer = BloomNewBuffer(index);
GenericXLogState *state;
state = GenericXLogStart(index);
page = GenericXLogRegisterBuffer(state, buffer, GENERIC_XLOG_FULL_IMAGE);
memcpy(page, buildstate->data, BLCKSZ);
GenericXLogFinish(state);
UnlockReleaseBuffer(buffer);
}
/*
* (Re)initialize cached page in BloomBuildState.
*/
static void
initCachedPage(BloomBuildState *buildstate)
{
memset(buildstate->data, 0, BLCKSZ);
BloomInitPage(buildstate->data, 0);
buildstate->count = 0;
}
/*
* Per-tuple callback from IndexBuildHeapScan.
*/
static void
bloomBuildCallback(Relation index, HeapTuple htup, Datum *values,
bool *isnull, bool tupleIsAlive, void *state)
{
BloomBuildState *buildstate = (BloomBuildState *) state;
MemoryContext oldCtx;
BloomTuple *itup;
oldCtx = MemoryContextSwitchTo(buildstate->tmpCtx);
itup = BloomFormTuple(&buildstate->blstate, &htup->t_self, values, isnull);
/* Try to add next item to cached page */
if (BloomPageAddItem(&buildstate->blstate, buildstate->data, itup))
{
/* Next item was added successfully */
buildstate->count++;
}
else
{
/* Cached page is full, flush it out and make a new one */
flushCachedPage(index, buildstate);
CHECK_FOR_INTERRUPTS();
initCachedPage(buildstate);
if (!BloomPageAddItem(&buildstate->blstate, buildstate->data, itup))
{
/* We shouldn't be here since we're inserting to the empty page */
elog(ERROR, "could not add new bloom tuple to empty page");
}
}
MemoryContextSwitchTo(oldCtx);
MemoryContextReset(buildstate->tmpCtx);
}
/*
* Build a new bloom index.
*/
IndexBuildResult *
blbuild(Relation heap, Relation index, IndexInfo *indexInfo)
{
IndexBuildResult *result;
double reltuples;
BloomBuildState buildstate;
if (RelationGetNumberOfBlocks(index) != 0)
elog(ERROR, "index \"%s\" already contains data",
RelationGetRelationName(index));
/* Initialize the meta page */
BloomInitMetapage(index);
/* Initialize the bloom build state */
memset(&buildstate, 0, sizeof(buildstate));
initBloomState(&buildstate.blstate, index);
buildstate.tmpCtx = AllocSetContextCreate(CurrentMemoryContext,
"Bloom build temporary context",
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
initCachedPage(&buildstate);
/* Do the heap scan */
reltuples = IndexBuildHeapScan(heap, index, indexInfo, true,
bloomBuildCallback, (void *) &buildstate);
/*
* There are could be some items in cached page. Flush this page
* if needed.
*/
if (buildstate.count > 0)
flushCachedPage(index, &buildstate);
MemoryContextDelete(buildstate.tmpCtx);
result = (IndexBuildResult *) palloc(sizeof(IndexBuildResult));
result->heap_tuples = result->index_tuples = reltuples;
return result;
}
/*
* Build an empty bloom index in the initialization fork.
*/
void
blbuildempty(Relation index)
{
Page metapage;
/* Construct metapage. */
metapage = (Page) palloc(BLCKSZ);
BloomFillMetapage(index, metapage);
/* Write the page. If archiving/streaming, XLOG it. */
PageSetChecksumInplace(metapage, BLOOM_METAPAGE_BLKNO);
smgrwrite(index->rd_smgr, INIT_FORKNUM, BLOOM_METAPAGE_BLKNO,
(char *) metapage, true);
if (XLogIsNeeded())
log_newpage(&index->rd_smgr->smgr_rnode.node, INIT_FORKNUM,
BLOOM_METAPAGE_BLKNO, metapage, false);
/*
* An immediate sync is required even if we xlog'd the page, because the
* write did not go through shared_buffers and therefore a concurrent
* checkpoint may have moved the redo pointer past our xlog record.
*/
smgrimmedsync(index->rd_smgr, INIT_FORKNUM);
}
/*
* Insert new tuple to the bloom index.
*/
bool
blinsert(Relation index, Datum *values, bool *isnull,
ItemPointer ht_ctid, Relation heapRel, IndexUniqueCheck checkUnique)
{
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_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
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);
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);
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;
}