コード例 #1
0
ファイル: xlogutils.c プロジェクト: Deepakkothandan/postgres
/*
 * XLogReadBufferExtended
 *		Read a page during XLOG replay
 *
 * This is functionally comparable to ReadBufferExtended. There's some
 * differences in the behavior wrt. the "mode" argument:
 *
 * In RBM_NORMAL mode, if the page doesn't exist, or contains all-zeroes, we
 * return InvalidBuffer. In this case the caller should silently skip the
 * update on this page. (In this situation, we expect that the page was later
 * dropped or truncated. If we don't see evidence of that later in the WAL
 * sequence, we'll complain at the end of WAL replay.)
 *
 * In RBM_ZERO and RBM_ZERO_ON_ERROR modes, if the page doesn't exist, the
 * relation is extended with all-zeroes pages up to the given block number.
 *
 * In RBM_NORMAL_NO_LOG mode, we return InvalidBuffer if the page doesn't
 * exist, and we don't check for all-zeroes.  Thus, no log entry is made
 * to imply that the page should be dropped or truncated later.
 */
Buffer
XLogReadBufferExtended(RelFileNode rnode, ForkNumber forknum,
					   BlockNumber blkno, ReadBufferMode mode)
{
	BlockNumber lastblock;
	Buffer		buffer;
	SMgrRelation smgr;

	Assert(blkno != P_NEW);

	/* Open the relation at smgr level */
	smgr = smgropen(rnode, InvalidBackendId);

	/*
	 * Create the target file if it doesn't already exist.  This lets us cope
	 * if the replay sequence contains writes to a relation that is later
	 * deleted.  (The original coding of this routine would instead suppress
	 * the writes, but that seems like it risks losing valuable data if the
	 * filesystem loses an inode during a crash.  Better to write the data
	 * until we are actually told to delete the file.)
	 */
	smgrcreate(smgr, forknum, true);

	lastblock = smgrnblocks(smgr, forknum);

	if (blkno < lastblock)
	{
		/* page exists in file */
		buffer = ReadBufferWithoutRelcache(rnode, forknum, blkno,
										   mode, NULL);
	}
	else
	{
		/* hm, page doesn't exist in file */
		if (mode == RBM_NORMAL)
		{
			log_invalid_page(rnode, forknum, blkno, false);
			return InvalidBuffer;
		}
		if (mode == RBM_NORMAL_NO_LOG)
			return InvalidBuffer;
		/* OK to extend the file */
		/* we do this in recovery only - no rel-extension lock needed */
		Assert(InRecovery);
		buffer = InvalidBuffer;
		do
		{
			if (buffer != InvalidBuffer)
				ReleaseBuffer(buffer);
			buffer = ReadBufferWithoutRelcache(rnode, forknum,
											   P_NEW, mode, NULL);
		}
		while (BufferGetBlockNumber(buffer) < blkno);
		/* Handle the corner case that P_NEW returns non-consecutive pages */
		if (BufferGetBlockNumber(buffer) != blkno)
		{
			ReleaseBuffer(buffer);
			buffer = ReadBufferWithoutRelcache(rnode, forknum, blkno,
											   mode, NULL);
		}
	}

	if (mode == RBM_NORMAL)
	{
		/* check that page has been initialized */
		Page		page = (Page) BufferGetPage(buffer);

		/*
		 * We assume that PageIsNew is safe without a lock. During recovery,
		 * there should be no other backends that could modify the buffer at
		 * the same time.
		 */
		if (PageIsNew(page))
		{
			ReleaseBuffer(buffer);
			log_invalid_page(rnode, forknum, blkno, true);
			return InvalidBuffer;
		}
	}

	return buffer;
}
コード例 #2
0
/* ------------------------------------------------
 * bt_metap()
 *
 * Get a btree meta-page information
 *
 * Usage: SELECT * FROM bt_metap('t1_pkey')
 * ------------------------------------------------
 */
Datum
bt_metap(PG_FUNCTION_ARGS)
{
	text	   *relname = PG_GETARG_TEXT_P(0);
	Buffer		buffer;

	Relation	rel;
	RangeVar   *relrv;
	Datum		result;

	if (!superuser())
		ereport(ERROR,
				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
				 (errmsg("must be superuser to use pgstattuple functions"))));

	relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
	rel = relation_openrv(relrv, AccessShareLock);

	if (!IS_INDEX(rel) || !IS_BTREE(rel))
		elog(ERROR, "bt_metap() can be used only on b-tree index.");

	/*
	 * Reject attempts to read non-local temporary relations; we would
	 * be likely to get wrong data since we have no visibility into the
	 * owning session's local buffers.
	 */
	if (isOtherTempNamespace(RelationGetNamespace(rel)))
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("cannot access temporary tables of other sessions")));

	buffer = ReadBuffer(rel, 0);

	{
		BTMetaPageData *metad;

		TupleDesc	tupleDesc;
		int			j;
		char	   *values[BTMETAP_NCOLUMNS];
		HeapTuple	tuple;

		Page		page = BufferGetPage(buffer);

		metad = BTPageGetMeta(page);

		tupleDesc = RelationNameGetTupleDesc(BTMETAP_TYPE);

		j = 0;
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", metad->btm_magic);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", metad->btm_version);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", metad->btm_root);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", metad->btm_level);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", metad->btm_fastroot);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", metad->btm_fastlevel);

		tuple = BuildTupleFromCStrings(TupleDescGetAttInMetadata(tupleDesc),
									   values);

		result = TupleGetDatum(TupleDescGetSlot(tupleDesc), tuple);
	}

	ReleaseBuffer(buffer);

	relation_close(rel, AccessShareLock);

	PG_RETURN_DATUM(result);
}
コード例 #3
0
ファイル: spgutils.c プロジェクト: a1exsh/postgres
/*
 * Get a buffer of the type and parity specified by flags, having at least
 * as much free space as indicated by needSpace.  We use the lastUsedPages
 * cache to assign the same buffer previously requested when possible.
 * The returned buffer is already pinned and exclusive-locked.
 *
 * *isNew is set true if the page was initialized here, false if it was
 * already valid.
 */
Buffer
SpGistGetBuffer(Relation index, int flags, int needSpace, bool *isNew)
{
	SpGistCache *cache = spgGetCache(index);
	SpGistLastUsedPage *lup;

	/* Bail out if even an empty page wouldn't meet the demand */
	if (needSpace > SPGIST_PAGE_CAPACITY)
		elog(ERROR, "desired SPGiST tuple size is too big");

	/*
	 * If possible, increase the space request to include relation's
	 * fillfactor.  This ensures that when we add unrelated tuples to a page,
	 * we try to keep 100-fillfactor% available for adding tuples that are
	 * related to the ones already on it.  But fillfactor mustn't cause an
	 * error for requests that would otherwise be legal.
	 */
	needSpace += RelationGetTargetPageFreeSpace(index,
												SPGIST_DEFAULT_FILLFACTOR);
	needSpace = Min(needSpace, SPGIST_PAGE_CAPACITY);

	/* Get the cache entry for this flags setting */
	lup = GET_LUP(cache, flags);

	/* If we have nothing cached, just turn it over to allocNewBuffer */
	if (lup->blkno == InvalidBlockNumber)
	{
		*isNew = true;
		return allocNewBuffer(index, flags);
	}

	/* fixed pages should never be in cache */
	Assert(!SpGistBlockIsFixed(lup->blkno));

	/* If cached freeSpace isn't enough, don't bother looking at the page */
	if (lup->freeSpace >= needSpace)
	{
		Buffer		buffer;
		Page		page;

		buffer = ReadBuffer(index, lup->blkno);

		if (!ConditionalLockBuffer(buffer))
		{
			/*
			 * buffer is locked by another process, so return a new buffer
			 */
			ReleaseBuffer(buffer);
			*isNew = true;
			return allocNewBuffer(index, flags);
		}

		page = BufferGetPage(buffer);

		if (PageIsNew(page) || SpGistPageIsDeleted(page) || PageIsEmpty(page))
		{
			/* OK to initialize the page */
			uint16		pageflags = 0;

			if (GBUF_REQ_LEAF(flags))
				pageflags |= SPGIST_LEAF;
			if (GBUF_REQ_NULLS(flags))
				pageflags |= SPGIST_NULLS;
			SpGistInitBuffer(buffer, pageflags);
			lup->freeSpace = PageGetExactFreeSpace(page) - needSpace;
			*isNew = true;
			return buffer;
		}

		/*
		 * Check that page is of right type and has enough space.  We must
		 * recheck this since our cache isn't necessarily up to date.
		 */
		if ((GBUF_REQ_LEAF(flags) ? SpGistPageIsLeaf(page) : !SpGistPageIsLeaf(page)) &&
			(GBUF_REQ_NULLS(flags) ? SpGistPageStoresNulls(page) : !SpGistPageStoresNulls(page)))
		{
			int			freeSpace = PageGetExactFreeSpace(page);

			if (freeSpace >= needSpace)
			{
				/* Success, update freespace info and return the buffer */
				lup->freeSpace = freeSpace - needSpace;
				*isNew = false;
				return buffer;
			}
		}

		/*
		 * fallback to allocation of new buffer
		 */
		UnlockReleaseBuffer(buffer);
	}

	/* No success with cache, so return a new buffer */
	*isNew = true;
	return allocNewBuffer(index, flags);
}
コード例 #4
0
ファイル: cdbpersistentstore.c プロジェクト: LJoNe/gpdb
static void PersistentStore_DiagnoseDumpTable(
	PersistentStoreData 		*storeData,
	PersistentStoreSharedData 	*storeSharedData)
{

	if (disable_persistent_diagnostic_dump)
	{
		return;
	}

	MIRROREDLOCK_BUFMGR_DECLARE;

	PersistentStoreScan storeScan;
	ItemPointerData			persistentTid;
	int64					persistentSerialNum;
	Datum					*values;
	BlockNumber				lastDisplayedBlockNum;
	bool					displayedOne;
	BlockNumber				currentBlockNum;

	elog(LOG, 
		 "Diagnostic dump of persistent table ('%s'): maximum in-use serial number " INT64_FORMAT ", maximum free order number " INT64_FORMAT ", free TID %s, maximum known TID %s",
		 storeData->tableName,
		 storeSharedData->maxInUseSerialNum, 
		 storeSharedData->maxFreeOrderNum, 
		 ItemPointerToString(&storeSharedData->freeTid),
		 ItemPointerToString2(&storeSharedData->maxTid));

	values = (Datum*)palloc(storeData->numAttributes * sizeof(Datum));

	PersistentStore_BeginScan(
						storeData,
						storeSharedData,
						&storeScan);

	lastDisplayedBlockNum = 0;
	displayedOne = false;
	while (PersistentStore_GetNext(
							&storeScan,
							values,
							&persistentTid,
							&persistentSerialNum))
	{
		/*
		 * Use the BlockIdGetBlockNumber routine because ItemPointerGetBlockNumber 
		 * asserts for valid TID.
		 */
		currentBlockNum = BlockIdGetBlockNumber(&persistentTid.ip_blkid);
		if (!displayedOne || currentBlockNum != lastDisplayedBlockNum)
		{
			Buffer		buffer;
			PageHeader	page;
			XLogRecPtr	lsn;

			/*
			 * Fetch the block and display the LSN.
			 */
			
			// -------- MirroredLock ----------
			MIRROREDLOCK_BUFMGR_LOCK;
			
			buffer = ReadBuffer(
							storeScan.persistentRel,
							currentBlockNum);

			page = (PageHeader) BufferGetPage(buffer);
			lsn = PageGetLSN(page);
			ReleaseBuffer(buffer);

			MIRROREDLOCK_BUFMGR_UNLOCK;
			// -------- MirroredLock ----------

			elog(LOG, "Diagnostic LSN %s of page %u",
				 XLogLocationToString(&lsn),
				 currentBlockNum);

			lastDisplayedBlockNum = currentBlockNum;
			displayedOne = true;
		}

		/*
		 * Display the persistent tuple.
		 */
		(*storeData->printTupleCallback)(
									LOG,
									"DIAGNOSE",
									&persistentTid,
									values);
	}
	
	PersistentStore_EndScan(&storeScan);

	pfree(values);
}
コード例 #5
0
/* -----------------------------------------------
 * bt_page()
 *
 * Usage: SELECT * FROM bt_page('t1_pkey', 0);
 * -----------------------------------------------
 */
Datum
bt_page_stats(PG_FUNCTION_ARGS)
{
	text	   *relname = PG_GETARG_TEXT_P(0);
	uint32		blkno = PG_GETARG_UINT32(1);
	Buffer		buffer;

	Relation	rel;
	RangeVar   *relrv;
	Datum		result;

	if (!superuser())
		ereport(ERROR,
				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
				 (errmsg("must be superuser to use pgstattuple functions"))));

	relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
	rel = relation_openrv(relrv, AccessShareLock);

	if (!IS_INDEX(rel) || !IS_BTREE(rel))
		elog(ERROR, "bt_page_stats() can be used only on b-tree index.");

	/*
	 * Reject attempts to read non-local temporary relations; we would
	 * be likely to get wrong data since we have no visibility into the
	 * owning session's local buffers.
	 */
	if (isOtherTempNamespace(RelationGetNamespace(rel)))
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("cannot access temporary tables of other sessions")));

	if (blkno == 0)
		elog(ERROR, "Block 0 is a meta page.");

	CHECK_RELATION_BLOCK_RANGE(rel, blkno);

	buffer = ReadBuffer(rel, blkno);

	{
		HeapTuple	tuple;
		TupleDesc	tupleDesc;
		int			j;
		char	   *values[BTPAGESTATS_NCOLUMNS];

		BTPageStat	stat;

		GetBTPageStatistics(blkno, buffer, &stat);

		tupleDesc = RelationNameGetTupleDesc(BTPAGESTATS_TYPE);

		j = 0;
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", stat.blkno);

		values[j] = palloc(32);
		snprintf(values[j++], 32, "%c", stat.type);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", stat.live_items);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", stat.dead_items);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", stat.avg_item_size);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", stat.page_size);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", stat.free_size);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", stat.btpo_prev);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", stat.btpo_next);

		values[j] = palloc(32);
		if (stat.type == 'd')
			snprintf(values[j++], 32, "%d", stat.btpo.xact);
		else
			snprintf(values[j++], 32, "%d", stat.btpo.level);

		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", stat.btpo_flags);

		tuple = BuildTupleFromCStrings(TupleDescGetAttInMetadata(tupleDesc),
									   values);

		result = TupleGetDatum(TupleDescGetSlot(tupleDesc), tuple);
	}

	ReleaseBuffer(buffer);

	relation_close(rel, AccessShareLock);

	PG_RETURN_DATUM(result);
}
コード例 #6
0
ファイル: hio.c プロジェクト: 42penguins/postgres
/*
 * RelationGetBufferForTuple
 *
 *	Returns pinned and exclusive-locked buffer of a page in given relation
 *	with free space >= given len.
 *
 *	If otherBuffer is not InvalidBuffer, then it references a previously
 *	pinned buffer of another page in the same relation; on return, this
 *	buffer will also be exclusive-locked.  (This case is used by heap_update;
 *	the otherBuffer contains the tuple being updated.)
 *
 *	The reason for passing otherBuffer is that if two backends are doing
 *	concurrent heap_update operations, a deadlock could occur if they try
 *	to lock the same two buffers in opposite orders.  To ensure that this
 *	can't happen, we impose the rule that buffers of a relation must be
 *	locked in increasing page number order.  This is most conveniently done
 *	by having RelationGetBufferForTuple lock them both, with suitable care
 *	for ordering.
 *
 *	NOTE: it is unlikely, but not quite impossible, for otherBuffer to be the
 *	same buffer we select for insertion of the new tuple (this could only
 *	happen if space is freed in that page after heap_update finds there's not
 *	enough there).	In that case, the page will be pinned and locked only once.
 *
 *	For the vmbuffer and vmbuffer_other arguments, we avoid deadlock by
 *	locking them only after locking the corresponding heap page, and taking
 *	no further lwlocks while they are locked.
 *
 *	We normally use FSM to help us find free space.  However,
 *	if HEAP_INSERT_SKIP_FSM is specified, we just append a new empty page to
 *	the end of the relation if the tuple won't fit on the current target page.
 *	This can save some cycles when we know the relation is new and doesn't
 *	contain useful amounts of free space.
 *
 *	HEAP_INSERT_SKIP_FSM is also useful for non-WAL-logged additions to a
 *	relation, if the caller holds exclusive lock and is careful to invalidate
 *	relation's smgr_targblock before the first insertion --- that ensures that
 *	all insertions will occur into newly added pages and not be intermixed
 *	with tuples from other transactions.  That way, a crash can't risk losing
 *	any committed data of other transactions.  (See heap_insert's comments
 *	for additional constraints needed for safe usage of this behavior.)
 *
 *	The caller can also provide a BulkInsertState object to optimize many
 *	insertions into the same relation.	This keeps a pin on the current
 *	insertion target page (to save pin/unpin cycles) and also passes a
 *	BULKWRITE buffer selection strategy object to the buffer manager.
 *	Passing NULL for bistate selects the default behavior.
 *
 *	We always try to avoid filling existing pages further than the fillfactor.
 *	This is OK since this routine is not consulted when updating a tuple and
 *	keeping it on the same page, which is the scenario fillfactor is meant
 *	to reserve space for.
 *
 *	ereport(ERROR) is allowed here, so this routine *must* be called
 *	before any (unlogged) changes are made in buffer pool.
 */
Buffer
RelationGetBufferForTuple(Relation relation, Size len,
						  Buffer otherBuffer, int options,
						  BulkInsertState bistate,
						  Buffer *vmbuffer, Buffer *vmbuffer_other)
{
	bool		use_fsm = !(options & HEAP_INSERT_SKIP_FSM);
	Buffer		buffer = InvalidBuffer;
	Page		page;
	Size		pageFreeSpace,
				saveFreeSpace;
	BlockNumber targetBlock,
				otherBlock;
	bool		needLock;

	len = MAXALIGN(len);		/* be conservative */

	/* Bulk insert is not supported for updates, only inserts. */
	Assert(otherBuffer == InvalidBuffer || !bistate);

	/*
	 * If we're gonna fail for oversize tuple, do it right away
	 */
	if (len > MaxHeapTupleSize)
		ereport(ERROR,
				(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
				 errmsg("row is too big: size %lu, maximum size %lu",
						(unsigned long) len,
						(unsigned long) MaxHeapTupleSize)));

	/* Compute desired extra freespace due to fillfactor option */
	saveFreeSpace = RelationGetTargetPageFreeSpace(relation,
												   HEAP_DEFAULT_FILLFACTOR);

	if (otherBuffer != InvalidBuffer)
		otherBlock = BufferGetBlockNumber(otherBuffer);
	else
		otherBlock = InvalidBlockNumber;		/* just to keep compiler quiet */

	/*
	 * We first try to put the tuple on the same page we last inserted a tuple
	 * on, as cached in the BulkInsertState or relcache entry.	If that
	 * doesn't work, we ask the Free Space Map to locate a suitable page.
	 * Since the FSM's info might be out of date, we have to be prepared to
	 * loop around and retry multiple times. (To insure this isn't an infinite
	 * loop, we must update the FSM with the correct amount of free space on
	 * each page that proves not to be suitable.)  If the FSM has no record of
	 * a page with enough free space, we give up and extend the relation.
	 *
	 * When use_fsm is false, we either put the tuple onto the existing target
	 * page or extend the relation.
	 */
	if (len + saveFreeSpace > MaxHeapTupleSize)
	{
		/* can't fit, don't bother asking FSM */
		targetBlock = InvalidBlockNumber;
		use_fsm = false;
	}
	else if (bistate && bistate->current_buf != InvalidBuffer)
		targetBlock = BufferGetBlockNumber(bistate->current_buf);
	else
		targetBlock = RelationGetTargetBlock(relation);

	if (targetBlock == InvalidBlockNumber && use_fsm)
	{
		/*
		 * We have no cached target page, so ask the FSM for an initial
		 * target.
		 */
		targetBlock = GetPageWithFreeSpace(relation, len + saveFreeSpace);

		/*
		 * If the FSM knows nothing of the rel, try the last page before we
		 * give up and extend.	This avoids one-tuple-per-page syndrome during
		 * bootstrapping or in a recently-started system.
		 */
		if (targetBlock == InvalidBlockNumber)
		{
			BlockNumber nblocks = RelationGetNumberOfBlocks(relation);

			if (nblocks > 0)
				targetBlock = nblocks - 1;
		}
	}

	while (targetBlock != InvalidBlockNumber)
	{
		/*
		 * Read and exclusive-lock the target block, as well as the other
		 * block if one was given, taking suitable care with lock ordering and
		 * the possibility they are the same block.
		 *
		 * If the page-level all-visible flag is set, caller will need to
		 * clear both that and the corresponding visibility map bit.  However,
		 * by the time we return, we'll have x-locked the buffer, and we don't
		 * want to do any I/O while in that state.	So we check the bit here
		 * before taking the lock, and pin the page if it appears necessary.
		 * Checking without the lock creates a risk of getting the wrong
		 * answer, so we'll have to recheck after acquiring the lock.
		 */
		if (otherBuffer == InvalidBuffer)
		{
			/* easy case */
			buffer = ReadBufferBI(relation, targetBlock, bistate);
			if (PageIsAllVisible(BufferGetPage(buffer)))
				visibilitymap_pin(relation, targetBlock, vmbuffer);
			LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
		}
		else if (otherBlock == targetBlock)
		{
			/* also easy case */
			buffer = otherBuffer;
			if (PageIsAllVisible(BufferGetPage(buffer)))
				visibilitymap_pin(relation, targetBlock, vmbuffer);
			LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
		}
		else if (otherBlock < targetBlock)
		{
			/* lock other buffer first */
			buffer = ReadBuffer(relation, targetBlock);
			if (PageIsAllVisible(BufferGetPage(buffer)))
				visibilitymap_pin(relation, targetBlock, vmbuffer);
			LockBuffer(otherBuffer, BUFFER_LOCK_EXCLUSIVE);
			LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
		}
		else
		{
			/* lock target buffer first */
			buffer = ReadBuffer(relation, targetBlock);
			if (PageIsAllVisible(BufferGetPage(buffer)))
				visibilitymap_pin(relation, targetBlock, vmbuffer);
			LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
			LockBuffer(otherBuffer, BUFFER_LOCK_EXCLUSIVE);
		}

		/*
		 * We now have the target page (and the other buffer, if any) pinned
		 * and locked.	However, since our initial PageIsAllVisible checks
		 * were performed before acquiring the lock, the results might now be
		 * out of date, either for the selected victim buffer, or for the
		 * other buffer passed by the caller.  In that case, we'll need to
		 * give up our locks, go get the pin(s) we failed to get earlier, and
		 * re-lock.  That's pretty painful, but hopefully shouldn't happen
		 * often.
		 *
		 * Note that there's a small possibility that we didn't pin the page
		 * above but still have the correct page pinned anyway, either because
		 * we've already made a previous pass through this loop, or because
		 * caller passed us the right page anyway.
		 *
		 * Note also that it's possible that by the time we get the pin and
		 * retake the buffer locks, the visibility map bit will have been
		 * cleared by some other backend anyway.  In that case, we'll have
		 * done a bit of extra work for no gain, but there's no real harm
		 * done.
		 */
		if (otherBuffer == InvalidBuffer || buffer <= otherBuffer)
			GetVisibilityMapPins(relation, buffer, otherBuffer,
								 targetBlock, otherBlock, vmbuffer,
								 vmbuffer_other);
		else
			GetVisibilityMapPins(relation, otherBuffer, buffer,
								 otherBlock, targetBlock, vmbuffer_other,
								 vmbuffer);

		/*
		 * Now we can check to see if there's enough free space here. If so,
		 * we're done.
		 */
		page = BufferGetPage(buffer);
		pageFreeSpace = PageGetHeapFreeSpace(page);
		if (len + saveFreeSpace <= pageFreeSpace)
		{
			/* use this page as future insert target, too */
			RelationSetTargetBlock(relation, targetBlock);
			return buffer;
		}

		/*
		 * Not enough space, so we must give up our page locks and pin (if
		 * any) and prepare to look elsewhere.	We don't care which order we
		 * unlock the two buffers in, so this can be slightly simpler than the
		 * code above.
		 */
		LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
		if (otherBuffer == InvalidBuffer)
			ReleaseBuffer(buffer);
		else if (otherBlock != targetBlock)
		{
			LockBuffer(otherBuffer, BUFFER_LOCK_UNLOCK);
			ReleaseBuffer(buffer);
		}

		/* Without FSM, always fall out of the loop and extend */
		if (!use_fsm)
			break;

		/*
		 * Update FSM as to condition of this page, and ask for another page
		 * to try.
		 */
		targetBlock = RecordAndGetPageWithFreeSpace(relation,
													targetBlock,
													pageFreeSpace,
													len + saveFreeSpace);
	}

	/*
	 * Have to extend the relation.
	 *
	 * We have to use a lock to ensure no one else is extending the rel at the
	 * same time, else we will both try to initialize the same new page.  We
	 * can skip locking for new or temp relations, however, since no one else
	 * could be accessing them.
	 */
	needLock = !RELATION_IS_LOCAL(relation);

	if (needLock)
		LockRelationForExtension(relation, ExclusiveLock);

	/*
	 * XXX This does an lseek - rather expensive - but at the moment it is the
	 * only way to accurately determine how many blocks are in a relation.	Is
	 * it worth keeping an accurate file length in shared memory someplace,
	 * rather than relying on the kernel to do it for us?
	 */
	buffer = ReadBufferBI(relation, P_NEW, bistate);

	/*
	 * We can be certain that locking the otherBuffer first is OK, since it
	 * must have a lower page number.
	 */
	if (otherBuffer != InvalidBuffer)
		LockBuffer(otherBuffer, BUFFER_LOCK_EXCLUSIVE);

	/*
	 * Now acquire lock on the new page.
	 */
	LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);

	/*
	 * Release the file-extension lock; it's now OK for someone else to extend
	 * the relation some more.	Note that we cannot release this lock before
	 * we have buffer lock on the new page, or we risk a race condition
	 * against vacuumlazy.c --- see comments therein.
	 */
	if (needLock)
		UnlockRelationForExtension(relation, ExclusiveLock);

	/*
	 * We need to initialize the empty new page.  Double-check that it really
	 * is empty (this should never happen, but if it does we don't want to
	 * risk wiping out valid data).
	 */
	page = BufferGetPage(buffer);

	if (!PageIsNew(page))
		elog(ERROR, "page %u of relation \"%s\" should be empty but is not",
			 BufferGetBlockNumber(buffer),
			 RelationGetRelationName(relation));

	PageInit(page, BufferGetPageSize(buffer), 0);

	if (len > PageGetHeapFreeSpace(page))
	{
		/* We should not get here given the test at the top */
		elog(PANIC, "tuple is too big: size %lu", (unsigned long) len);
	}

	/*
	 * Remember the new page as our target for future insertions.
	 *
	 * XXX should we enter the new page into the free space map immediately,
	 * or just keep it for this backend's exclusive use in the short run
	 * (until VACUUM sees it)?	Seems to depend on whether you expect the
	 * current backend to make more insertions or not, which is probably a
	 * good bet most of the time.  So for now, don't add it to FSM yet.
	 */
	RelationSetTargetBlock(relation, BufferGetBlockNumber(buffer));

	return buffer;
}
コード例 #7
0
ファイル: cdbpersistentstore.c プロジェクト: LJoNe/gpdb
void PersistentStore_ReplaceTuple(
	PersistentStoreData 		*storeData,
	PersistentStoreSharedData 	*storeSharedData,
	ItemPointer 			persistentTid,
				/* TID of the stored tuple. */
	HeapTuple				tuple,
	Datum					*newValues,
	bool					*replaces,
	bool					flushToXLog)
				/* When true, the XLOG record for this change will be flushed to disk. */
{
	Relation	persistentRel;
	bool 		*nulls;
	HeapTuple	replacementTuple = NULL;
	XLogRecPtr 	xlogUpdateEndLoc;
	
#ifdef USE_ASSERT_CHECKING
	if (storeSharedData == NULL ||
		!PersistentStoreSharedData_EyecatcherIsValid(storeSharedData))
		elog(ERROR, "Persistent store shared-memory not valid");
#endif
	
	if (Debug_persistent_store_print)
		elog(PersistentStore_DebugPrintLevel(), 
			 "PersistentStore_ReplaceTuple: Going to replace set of columns in tuple at TID %s ('%s', shared data %p)",
			 ItemPointerToString(persistentTid),
			 storeData->tableName,
			 storeSharedData);

	persistentRel = (*storeData->openRel)();

	/*
	 * In order to keep the tuples the exact same size to enable direct reuse of
	 * free tuples, we do not use NULLs.
	 */
	nulls = (bool*)palloc0(storeData->numAttributes * sizeof(bool));
		
	/*
	 * Modify the tuple.
	 */
	replacementTuple = heap_modify_tuple(tuple, persistentRel->rd_att, 
										 newValues, nulls, replaces);

	replacementTuple->t_self = *persistentTid;
		
	frozen_heap_inplace_update(persistentRel, replacementTuple);

	/*
	 * Return the XLOG location of the UPDATE tuple's XLOG record.
	 */
	xlogUpdateEndLoc = XLogLastInsertEndLoc();

	heap_freetuple(replacementTuple);
	pfree(nulls);

	if (Debug_persistent_store_print)
	{
		Datum 			*readValues;
		bool			*readNulls;
		HeapTupleData 	readTuple;
		Buffer			buffer;
		HeapTuple		readTupleCopy;
		
		elog(PersistentStore_DebugPrintLevel(), 
			 "PersistentStore_ReplaceTuple: Replaced set of columns in tuple at TID %s ('%s')",
			 ItemPointerToString(persistentTid),
			 storeData->tableName);
		
		readValues = (Datum*)palloc(storeData->numAttributes * sizeof(Datum));
		readNulls = (bool*)palloc(storeData->numAttributes * sizeof(bool));

		readTuple.t_self = *persistentTid;
		
		if (!heap_fetch(persistentRel, SnapshotAny,
						&readTuple, &buffer, false, NULL))
		{
			elog(ERROR, "Failed to fetch persistent tuple at %s ('%s')",
				 ItemPointerToString(&readTuple.t_self),
				 storeData->tableName);
		}
		
		
		readTupleCopy = heaptuple_copy_to(&readTuple, NULL, NULL);
		
		ReleaseBuffer(buffer);
		
		heap_deform_tuple(readTupleCopy, persistentRel->rd_att, readValues, readNulls);
		
		(*storeData->printTupleCallback)(
									PersistentStore_DebugPrintLevel(),
									"STORE REPLACED TUPLE",
									persistentTid,
									readValues);

		heap_freetuple(readTupleCopy);
		pfree(readValues);
		pfree(readNulls);
	}

	(*storeData->closeRel)(persistentRel);
	
	if (flushToXLog)
	{
		XLogFlush(xlogUpdateEndLoc);
		XLogRecPtr_Zero(&nowaitXLogEndLoc);
	}
	else
		nowaitXLogEndLoc = xlogUpdateEndLoc;
}
コード例 #8
0
ファイル: hashpage.c プロジェクト: adunstan/postgresql-dev
/*
 *	_hash_dropbuf() -- release an unlocked buffer.
 *
 * This is used to unpin a buffer on which we hold no lock.
 */
void
_hash_dropbuf(Relation rel, Buffer buf)
{
	ReleaseBuffer(buf);
}
コード例 #9
0
ファイル: wmv9.cpp プロジェクト: 3s3s/lavfilters
STDMETHODIMP CDecWMV9::ProcessOutput()
{
  HRESULT hr = S_OK;
  DWORD dwStatus = 0;

  BYTE *pBuffer = GetBuffer(m_pRawBufferSize);
  CMediaBuffer *pOutBuffer = new CMediaBuffer(pBuffer, m_pRawBufferSize, true);
  pOutBuffer->SetLength(0);

  DMO_OUTPUT_DATA_BUFFER OutputBufferStructs[1];
  memset(&OutputBufferStructs[0], 0, sizeof(DMO_OUTPUT_DATA_BUFFER));
  OutputBufferStructs[0].pBuffer  = pOutBuffer;

  hr = m_pDMO->ProcessOutput(0, 1, OutputBufferStructs, &dwStatus);
  if (FAILED(hr)) {
    ReleaseBuffer(pBuffer);
    DbgLog((LOG_TRACE, 10, L"-> ProcessOutput failed with hr: %x", hr));
    return S_FALSE;
  }
  if (hr == S_FALSE) {
    ReleaseBuffer(pBuffer);
    return S_FALSE;
  }

  LAVFrame *pFrame = nullptr;
  AllocateFrame(&pFrame);

  BITMAPINFOHEADER *pBMI = nullptr;
  videoFormatTypeHandler(mtOut, &pBMI);
  pFrame->width     = pBMI->biWidth;
  pFrame->height    = pBMI->biHeight;
  pFrame->format    = m_OutPixFmt;
  pFrame->key_frame = (OutputBufferStructs[0].dwStatus & DMO_OUTPUT_DATA_BUFFERF_SYNCPOINT);

  AVRational display_aspect_ratio;
  int64_t num = (int64_t)m_StreamAR.num * pBMI->biWidth;
  int64_t den = (int64_t)m_StreamAR.den * pBMI->biHeight;
  av_reduce(&display_aspect_ratio.num, &display_aspect_ratio.den, num, den, INT_MAX);

  BYTE contentType = 0;
  DWORD dwPropSize = 1;
  pOutBuffer->GetProperty(WM_SampleExtensionGUID_ContentType, &contentType, &dwPropSize);
  pFrame->interlaced = !!(contentType & WM_CT_INTERLACED);
  pFrame->repeat     = !!(contentType & WM_CT_REPEAT_FIRST_FIELD);

  LAVDeintFieldOrder fo = m_pSettings->GetDeintFieldOrder();
  pFrame->tff           = (fo == DeintFieldOrder_Auto) ? !!(contentType & WM_CT_TOP_FIELD_FIRST) : (fo == DeintFieldOrder_TopFieldFirst);

  if (pFrame->interlaced && !m_bInterlaced)
    m_bInterlaced = TRUE;

  pFrame->interlaced = (pFrame->interlaced || (m_bInterlaced && m_pSettings->GetDeinterlacingMode() == DeintMode_Aggressive) || m_pSettings->GetDeinterlacingMode() == DeintMode_Force) && !(m_pSettings->GetDeinterlacingMode() == DeintMode_Disable);

  if (m_bManualReorder) {
    if (!m_timestampQueue.empty()) {
      pFrame->rtStart = m_timestampQueue.front();
      m_timestampQueue.pop();
      if (OutputBufferStructs[0].dwStatus & DMO_OUTPUT_DATA_BUFFERF_TIMELENGTH) {
        pFrame->rtStop = pFrame->rtStart + OutputBufferStructs[0].rtTimelength;
      }
    }
  } else {
    if (OutputBufferStructs[0].dwStatus & DMO_OUTPUT_DATA_BUFFERF_TIME) {
      pFrame->rtStart = OutputBufferStructs[0].rtTimestamp;
      if (OutputBufferStructs[0].dwStatus & DMO_OUTPUT_DATA_BUFFERF_TIMELENGTH) {
        pFrame->rtStop = pFrame->rtStart + OutputBufferStructs[0].rtTimelength;
      }
    }
  }

  // Check alignment
  // If not properly aligned, we need to make the data aligned.
  int alignment = (m_OutPixFmt == LAVPixFmt_NV12) ? 16 : 32;
  if ((pFrame->width % alignment) != 0) {
    AllocLAVFrameBuffers(pFrame);
    size_t ySize = pFrame->width * pFrame->height;
    memcpy_plane(pFrame->data[0], pBuffer, pFrame->width, pFrame->stride[0], pFrame->height);
    if (m_OutPixFmt == LAVPixFmt_NV12) {
      memcpy_plane(pFrame->data[1], pBuffer+ySize, pFrame->width, pFrame->stride[1], pFrame->height / 2);
    } else if (m_OutPixFmt == LAVPixFmt_YUV420) {
      size_t uvSize = ySize / 4;
      memcpy_plane(pFrame->data[2], pBuffer+ySize, pFrame->width / 2, pFrame->stride[2], pFrame->height / 2);
      memcpy_plane(pFrame->data[1], pBuffer+ySize+uvSize, pFrame->width / 2, pFrame->stride[1], pFrame->height / 2);
    }
    ReleaseBuffer(pBuffer);
  } else {
    if (m_OutPixFmt == LAVPixFmt_NV12) {
      pFrame->data[0] = pBuffer;
      pFrame->data[1] = pBuffer + pFrame->width * pFrame->height;
      pFrame->stride[0] = pFrame->stride[1] = pFrame->width;
    } else if (m_OutPixFmt == LAVPixFmt_YUV420) {
      pFrame->data[0] = pBuffer;
      pFrame->data[2] = pBuffer + pFrame->width * pFrame->height;
      pFrame->data[1] = pFrame->data[2] + (pFrame->width / 2) * (pFrame->height / 2);
      pFrame->stride[0] = pFrame->width;
      pFrame->stride[1] = pFrame->stride[2] = pFrame->width / 2;
    }
    pFrame->destruct = wmv9_buffer_destruct;
    pFrame->priv_data = this;
  }
  pFrame->flags |= LAV_FRAME_FLAG_BUFFER_MODIFY;
  Deliver(pFrame);

  SafeRelease(&pOutBuffer);

  if (OutputBufferStructs[0].dwStatus & DMO_OUTPUT_DATA_BUFFERF_INCOMPLETE)
    return ProcessOutput();
  return hr;
}
コード例 #10
0
ファイル: execReplication.c プロジェクト: RingsC/postgres
/*
 * Search the relation 'rel' for tuple using the index.
 *
 * If a matching tuple is found, lock it with lockmode, fill the slot with its
 * contents, and return true.  Return false otherwise.
 */
bool
RelationFindReplTupleByIndex(Relation rel, Oid idxoid,
							 LockTupleMode lockmode,
							 TupleTableSlot *searchslot,
							 TupleTableSlot *outslot)
{
	HeapTuple	scantuple;
	ScanKeyData skey[INDEX_MAX_KEYS];
	IndexScanDesc scan;
	SnapshotData snap;
	TransactionId xwait;
	Relation	idxrel;
	bool		found;

	/* Open the index. */
	idxrel = index_open(idxoid, RowExclusiveLock);

	/* Start an index scan. */
	InitDirtySnapshot(snap);
	scan = index_beginscan(rel, idxrel, &snap,
						   IndexRelationGetNumberOfKeyAttributes(idxrel),
						   0);

	/* Build scan key. */
	build_replindex_scan_key(skey, rel, idxrel, searchslot);

retry:
	found = false;

	index_rescan(scan, skey, IndexRelationGetNumberOfKeyAttributes(idxrel), NULL, 0);

	/* Try to find the tuple */
	if ((scantuple = index_getnext(scan, ForwardScanDirection)) != NULL)
	{
		found = true;
		ExecStoreTuple(scantuple, outslot, InvalidBuffer, false);
		ExecMaterializeSlot(outslot);

		xwait = TransactionIdIsValid(snap.xmin) ?
			snap.xmin : snap.xmax;

		/*
		 * If the tuple is locked, wait for locking transaction to finish and
		 * retry.
		 */
		if (TransactionIdIsValid(xwait))
		{
			XactLockTableWait(xwait, NULL, NULL, XLTW_None);
			goto retry;
		}
	}

	/* Found tuple, try to lock it in the lockmode. */
	if (found)
	{
		Buffer		buf;
		HeapUpdateFailureData hufd;
		HTSU_Result res;
		HeapTupleData locktup;

		ItemPointerCopy(&outslot->tts_tuple->t_self, &locktup.t_self);

		PushActiveSnapshot(GetLatestSnapshot());

		res = heap_lock_tuple(rel, &locktup, GetCurrentCommandId(false),
							  lockmode,
							  LockWaitBlock,
							  false /* don't follow updates */ ,
							  &buf, &hufd);
		/* the tuple slot already has the buffer pinned */
		ReleaseBuffer(buf);

		PopActiveSnapshot();

		switch (res)
		{
			case HeapTupleMayBeUpdated:
				break;
			case HeapTupleUpdated:
				/* XXX: Improve handling here */
				if (ItemPointerIndicatesMovedPartitions(&hufd.ctid))
					ereport(LOG,
							(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
							 errmsg("tuple to be locked was already moved to another partition due to concurrent update, retrying")));
				else
					ereport(LOG,
							(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
							 errmsg("concurrent update, retrying")));
				goto retry;
			case HeapTupleInvisible:
				elog(ERROR, "attempted to lock invisible tuple");
			default:
				elog(ERROR, "unexpected heap_lock_tuple status: %u", res);
				break;
		}
	}

	index_endscan(scan);

	/* Don't release lock until commit. */
	index_close(idxrel, NoLock);

	return found;
}
コード例 #11
0
ファイル: execReplication.c プロジェクト: RingsC/postgres
/*
 * Search the relation 'rel' for tuple using the sequential scan.
 *
 * If a matching tuple is found, lock it with lockmode, fill the slot with its
 * contents, and return true.  Return false otherwise.
 *
 * Note that this stops on the first matching tuple.
 *
 * This can obviously be quite slow on tables that have more than few rows.
 */
bool
RelationFindReplTupleSeq(Relation rel, LockTupleMode lockmode,
						 TupleTableSlot *searchslot, TupleTableSlot *outslot)
{
	HeapTuple	scantuple;
	HeapScanDesc scan;
	SnapshotData snap;
	TransactionId xwait;
	bool		found;
	TupleDesc	desc = RelationGetDescr(rel);

	Assert(equalTupleDescs(desc, outslot->tts_tupleDescriptor));

	/* Start a heap scan. */
	InitDirtySnapshot(snap);
	scan = heap_beginscan(rel, &snap, 0, NULL);

retry:
	found = false;

	heap_rescan(scan, NULL);

	/* Try to find the tuple */
	while ((scantuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
	{
		if (!tuple_equals_slot(desc, scantuple, searchslot))
			continue;

		found = true;
		ExecStoreTuple(scantuple, outslot, InvalidBuffer, false);
		ExecMaterializeSlot(outslot);

		xwait = TransactionIdIsValid(snap.xmin) ?
			snap.xmin : snap.xmax;

		/*
		 * If the tuple is locked, wait for locking transaction to finish and
		 * retry.
		 */
		if (TransactionIdIsValid(xwait))
		{
			XactLockTableWait(xwait, NULL, NULL, XLTW_None);
			goto retry;
		}
	}

	/* Found tuple, try to lock it in the lockmode. */
	if (found)
	{
		Buffer		buf;
		HeapUpdateFailureData hufd;
		HTSU_Result res;
		HeapTupleData locktup;

		ItemPointerCopy(&outslot->tts_tuple->t_self, &locktup.t_self);

		PushActiveSnapshot(GetLatestSnapshot());

		res = heap_lock_tuple(rel, &locktup, GetCurrentCommandId(false),
							  lockmode,
							  LockWaitBlock,
							  false /* don't follow updates */ ,
							  &buf, &hufd);
		/* the tuple slot already has the buffer pinned */
		ReleaseBuffer(buf);

		PopActiveSnapshot();

		switch (res)
		{
			case HeapTupleMayBeUpdated:
				break;
			case HeapTupleUpdated:
				/* XXX: Improve handling here */
				if (ItemPointerIndicatesMovedPartitions(&hufd.ctid))
					ereport(LOG,
							(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
							 errmsg("tuple to be locked was already moved to another partition due to concurrent update, retrying")));
				else
					ereport(LOG,
							(errcode(ERRCODE_T_R_SERIALIZATION_FAILURE),
							 errmsg("concurrent update, retrying")));
				goto retry;
			case HeapTupleInvisible:
				elog(ERROR, "attempted to lock invisible tuple");
			default:
				elog(ERROR, "unexpected heap_lock_tuple status: %u", res);
				break;
		}
	}

	heap_endscan(scan);

	return found;
}
コード例 #12
0
void C_TCPServerConnection::run()
{
	assert(m_pMsgConsolePrompter);
	m_pMsgConsolePrompter->PromptMessageLineBy(_T("TCP_CONNECTION_0"));

	socket().setReceiveTimeout(Poco::Timespan(90,0));

	try
	{
		char* pszCmdBuffer = NULL;

		while (true)
		{
			long nCmdLen = 0;
			recvData(socket(), &pszCmdBuffer, nCmdLen);

			if (nCmdLen == 0)
			{
				if (!m_szClientID.empty())
				{
					C_NetCmdLogOff logOff;
					logOff.HandleRequest(socket(), NULL, m_DBOperate, m_szClientID.c_str());
				}

				m_pMsgConsolePrompter->PromptMessageLineBy(_T("TCP_CONNECTION_1"));
				break;
			}

			if (nCmdLen > 0)
			{
				C_NetCommandDecomposer netCmdDecomposer;
				if(!netCmdDecomposer.Decompose(pszCmdBuffer))
				{
					ReleaseBuffer(&pszCmdBuffer);
					continue;
				}

				tstring szCmdName = netCmdDecomposer.GetCmdName().c_str();
				C_NetCommand* pRequestCmd = m_NetCmder.CreateCommand(szCmdName.c_str(), netCmdDecomposer.GetCmdType().c_str());
				
				if(pRequestCmd == NULL)
				{
					ReleaseBuffer(&pszCmdBuffer);
					continue;
				}

				if(szCmdName ==_T("log on") || szCmdName ==_T("log off") || szCmdName == _T("fetch channels") || szCmdName == _T("fetch content"))
				{
					if(!m_bLogOn)
					{	
						C_NetCmdLogOn *pLogOn = dynamic_cast<C_NetCmdLogOn*>(pRequestCmd);
						if(pLogOn == NULL)
							continue;

						tstring szMac = netCmdDecomposer.GetCmdPara(_T("id"));
						if( pLogOn->HandleRequest(socket(), pszCmdBuffer, m_DBOperate, szMac.c_str()) )
						{
							m_szClientID = szMac;
							m_bLogOn = true;
							ReleaseBuffer(&pszCmdBuffer);
							pLogOn->Release();
							C_AreaEvent::GetInstance()->PushEvent(socket(), szMac.c_str());
						}
						continue;
					}
				}
				
				pRequestCmd->HandleRequest(socket(), pszCmdBuffer, m_DBOperate, m_szClientID.c_str());
				pRequestCmd->Release();
				ReleaseBuffer(&pszCmdBuffer);
			}
		}
	}
	catch (Poco::Exception& exc)
	{
		if (!m_szClientID.empty())
		{
			C_NetCmdLogOff logOff;
			logOff.HandleRequest(socket(), NULL, m_DBOperate, m_szClientID.c_str());
		}
		m_pMsgConsolePrompter->PromptMessageLineBy(_T("TCP_CONNECTION_2"), exc.what());
		return;
	}
}
コード例 #13
0
ファイル: rawpage.c プロジェクト: adunstan/pg-cvs-mirror
/*
 * workhorse
 */
static bytea *
get_raw_page_internal(text *relname, ForkNumber forknum, BlockNumber blkno)
{
	bytea	   *raw_page;
	RangeVar   *relrv;
	Relation	rel;
	char	   *raw_page_data;
	Buffer		buf;

	if (!superuser())
		ereport(ERROR,
				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
				 (errmsg("must be superuser to use raw functions"))));

	relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
	rel = relation_openrv(relrv, AccessShareLock);

	/* Check that this relation has storage */
	if (rel->rd_rel->relkind == RELKIND_VIEW)
		ereport(ERROR,
				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
				 errmsg("cannot get raw page from view \"%s\"",
						RelationGetRelationName(rel))));
	if (rel->rd_rel->relkind == RELKIND_COMPOSITE_TYPE)
		ereport(ERROR,
				(errcode(ERRCODE_WRONG_OBJECT_TYPE),
				 errmsg("cannot get raw page from composite type \"%s\"",
						RelationGetRelationName(rel))));

	/*
	 * Reject attempts to read non-local temporary relations; we would be
	 * likely to get wrong data since we have no visibility into the owning
	 * session's local buffers.
	 */
	if (RELATION_IS_OTHER_TEMP(rel))
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("cannot access temporary tables of other sessions")));

	if (blkno >= RelationGetNumberOfBlocks(rel))
		elog(ERROR, "block number %u is out of range for relation \"%s\"",
			 blkno, RelationGetRelationName(rel));

	/* Initialize buffer to copy to */
	raw_page = (bytea *) palloc(BLCKSZ + VARHDRSZ);
	SET_VARSIZE(raw_page, BLCKSZ + VARHDRSZ);
	raw_page_data = VARDATA(raw_page);

	/* Take a verbatim copy of the page */

	buf = ReadBufferExtended(rel, forknum, blkno, RBM_NORMAL, NULL);
	LockBuffer(buf, BUFFER_LOCK_SHARE);

	memcpy(raw_page_data, BufferGetPage(buf), BLCKSZ);

	LockBuffer(buf, BUFFER_LOCK_UNLOCK);
	ReleaseBuffer(buf);

	relation_close(rel, AccessShareLock);

	return raw_page;
}
コード例 #14
0
ファイル: pg_prewarm.c プロジェクト: winlibs/postgresql
/*
 * pg_prewarm(regclass, mode text, fork text,
 *			  first_block int8, last_block int8)
 *
 * The first argument is the relation to be prewarmed; the second controls
 * how prewarming is done; legal options are 'prefetch', 'read', and 'buffer'.
 * The third is the name of the relation fork to be prewarmed.  The fourth
 * and fifth arguments specify the first and last block to be prewarmed.
 * If the fourth argument is NULL, it will be taken as 0; if the fifth argument
 * is NULL, it will be taken as the number of blocks in the relation.  The
 * return value is the number of blocks successfully prewarmed.
 */
Datum
pg_prewarm(PG_FUNCTION_ARGS)
{
	Oid			relOid;
	text	   *forkName;
	text	   *type;
	int64		first_block;
	int64		last_block;
	int64		nblocks;
	int64		blocks_done = 0;
	int64		block;
	Relation	rel;
	ForkNumber	forkNumber;
	char	   *forkString;
	char	   *ttype;
	PrewarmType ptype;
	AclResult	aclresult;

	/* Basic sanity checking. */
	if (PG_ARGISNULL(0))
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
				 errmsg("relation cannot be null")));
	relOid = PG_GETARG_OID(0);
	if (PG_ARGISNULL(1))
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
				 (errmsg("prewarm type cannot be null"))));
	type = PG_GETARG_TEXT_P(1);
	ttype = text_to_cstring(type);
	if (strcmp(ttype, "prefetch") == 0)
		ptype = PREWARM_PREFETCH;
	else if (strcmp(ttype, "read") == 0)
		ptype = PREWARM_READ;
	else if (strcmp(ttype, "buffer") == 0)
		ptype = PREWARM_BUFFER;
	else
	{
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
				 errmsg("invalid prewarm type"),
				 errhint("Valid prewarm types are \"prefetch\", \"read\", and \"buffer\".")));
		PG_RETURN_INT64(0);		/* Placate compiler. */
	}
	if (PG_ARGISNULL(2))
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
				 (errmsg("relation fork cannot be null"))));
	forkName = PG_GETARG_TEXT_P(2);
	forkString = text_to_cstring(forkName);
	forkNumber = forkname_to_number(forkString);

	/* Open relation and check privileges. */
	rel = relation_open(relOid, AccessShareLock);
	aclresult = pg_class_aclcheck(relOid, GetUserId(), ACL_SELECT);
	if (aclresult != ACLCHECK_OK)
		aclcheck_error(aclresult, ACL_KIND_CLASS, get_rel_name(relOid));

	/* Check that the fork exists. */
	RelationOpenSmgr(rel);
	if (!smgrexists(rel->rd_smgr, forkNumber))
		ereport(ERROR,
				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
				 errmsg("fork \"%s\" does not exist for this relation",
						forkString)));

	/* Validate block numbers, or handle nulls. */
	nblocks = RelationGetNumberOfBlocksInFork(rel, forkNumber);
	if (PG_ARGISNULL(3))
		first_block = 0;
	else
	{
		first_block = PG_GETARG_INT64(3);
		if (first_block < 0 || first_block >= nblocks)
			ereport(ERROR,
					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
					 errmsg("starting block number must be between 0 and " INT64_FORMAT,
							nblocks - 1)));
	}
	if (PG_ARGISNULL(4))
		last_block = nblocks - 1;
	else
	{
		last_block = PG_GETARG_INT64(4);
		if (last_block < 0 || last_block >= nblocks)
			ereport(ERROR,
					(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
			errmsg("ending block number must be between 0 and " INT64_FORMAT,
				   nblocks - 1)));
	}

	/* Now we're ready to do the real work. */
	if (ptype == PREWARM_PREFETCH)
	{
#ifdef USE_PREFETCH

		/*
		 * In prefetch mode, we just hint the OS to read the blocks, but we
		 * don't know whether it really does it, and we don't wait for it to
		 * finish.
		 *
		 * It would probably be better to pass our prefetch requests in chunks
		 * of a megabyte or maybe even a whole segment at a time, but there's
		 * no practical way to do that at present without a gross modularity
		 * violation, so we just do this.
		 */
		for (block = first_block; block <= last_block; ++block)
		{
			CHECK_FOR_INTERRUPTS();
			PrefetchBuffer(rel, forkNumber, block);
			++blocks_done;
		}
#else
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("prefetch is not supported by this build")));
#endif
	}
	else if (ptype == PREWARM_READ)
	{
		/*
		 * In read mode, we actually read the blocks, but not into shared
		 * buffers.  This is more portable than prefetch mode (it works
		 * everywhere) and is synchronous.
		 */
		for (block = first_block; block <= last_block; ++block)
		{
			CHECK_FOR_INTERRUPTS();
			smgrread(rel->rd_smgr, forkNumber, block, blockbuffer.data);
			++blocks_done;
		}
	}
	else if (ptype == PREWARM_BUFFER)
	{
		/*
		 * In buffer mode, we actually pull the data into shared_buffers.
		 */
		for (block = first_block; block <= last_block; ++block)
		{
			Buffer		buf;

			CHECK_FOR_INTERRUPTS();
			buf = ReadBufferExtended(rel, forkNumber, block, RBM_NORMAL, NULL);
			ReleaseBuffer(buf);
			++blocks_done;
		}
	}

	/* Close relation, release lock. */
	relation_close(rel, AccessShareLock);

	PG_RETURN_INT64(blocks_done);
}
コード例 #15
0
FarString& FarString::TrimRight()
{
  FarSF::RTrim (GetBuffer());
  ReleaseBuffer();
  return * this;
}
コード例 #16
0
ファイル: ginvacuum.c プロジェクト: Gordiychuk/postgres
/*
 * Delete a posting tree page.
 */
static void
ginDeletePage(GinVacuumState *gvs, BlockNumber deleteBlkno, BlockNumber leftBlkno,
			  BlockNumber parentBlkno, OffsetNumber myoff, bool isParentRoot)
{
	Buffer		dBuffer;
	Buffer		lBuffer;
	Buffer		pBuffer;
	Page		page,
				parentPage;
	BlockNumber rightlink;

	/*
	 * Lock the pages in the same order as an insertion would, to avoid
	 * deadlocks: left, then right, then parent.
	 */
	lBuffer = ReadBufferExtended(gvs->index, MAIN_FORKNUM, leftBlkno,
								 RBM_NORMAL, gvs->strategy);
	dBuffer = ReadBufferExtended(gvs->index, MAIN_FORKNUM, deleteBlkno,
								 RBM_NORMAL, gvs->strategy);
	pBuffer = ReadBufferExtended(gvs->index, MAIN_FORKNUM, parentBlkno,
								 RBM_NORMAL, gvs->strategy);

	LockBuffer(lBuffer, GIN_EXCLUSIVE);
	LockBuffer(dBuffer, GIN_EXCLUSIVE);
	if (!isParentRoot)			/* parent is already locked by
								 * LockBufferForCleanup() */
		LockBuffer(pBuffer, GIN_EXCLUSIVE);

	START_CRIT_SECTION();

	/* Unlink the page by changing left sibling's rightlink */
	page = BufferGetPage(dBuffer);
	rightlink = GinPageGetOpaque(page)->rightlink;

	page = BufferGetPage(lBuffer);
	GinPageGetOpaque(page)->rightlink = rightlink;

	/* Delete downlink from parent */
	parentPage = BufferGetPage(pBuffer);
#ifdef USE_ASSERT_CHECKING
	do
	{
		PostingItem *tod = GinDataPageGetPostingItem(parentPage, myoff);

		Assert(PostingItemGetBlockNumber(tod) == deleteBlkno);
	} while (0);
#endif
	GinPageDeletePostingItem(parentPage, myoff);

	page = BufferGetPage(dBuffer);

	/*
	 * we shouldn't change rightlink field to save workability of running
	 * search scan
	 */
	GinPageGetOpaque(page)->flags = GIN_DELETED;

	MarkBufferDirty(pBuffer);
	MarkBufferDirty(lBuffer);
	MarkBufferDirty(dBuffer);

	if (RelationNeedsWAL(gvs->index))
	{
		XLogRecPtr	recptr;
		ginxlogDeletePage data;

		/*
		 * We can't pass REGBUF_STANDARD for the deleted page, because we
		 * didn't set pd_lower on pre-9.4 versions. The page might've been
		 * binary-upgraded from an older version, and hence not have pd_lower
		 * set correctly. Ditto for the left page, but removing the item from
		 * the parent updated its pd_lower, so we know that's OK at this
		 * point.
		 */
		XLogBeginInsert();
		XLogRegisterBuffer(0, dBuffer, 0);
		XLogRegisterBuffer(1, pBuffer, REGBUF_STANDARD);
		XLogRegisterBuffer(2, lBuffer, 0);

		data.parentOffset = myoff;
		data.rightLink = GinPageGetOpaque(page)->rightlink;

		XLogRegisterData((char *) &data, sizeof(ginxlogDeletePage));

		recptr = XLogInsert(RM_GIN_ID, XLOG_GIN_DELETE_PAGE);
		PageSetLSN(page, recptr);
		PageSetLSN(parentPage, recptr);
		PageSetLSN(BufferGetPage(lBuffer), recptr);
	}

	if (!isParentRoot)
		LockBuffer(pBuffer, GIN_UNLOCK);
	ReleaseBuffer(pBuffer);
	UnlockReleaseBuffer(lBuffer);
	UnlockReleaseBuffer(dBuffer);

	END_CRIT_SECTION();

	gvs->result->pages_deleted++;
}
コード例 #17
0
FarString& FarString::Unquote()
{
  FarSF::Unquote( GetBuffer() );
  ReleaseBuffer();
  return * this;
}
コード例 #18
0
ファイル: ginvacuum.c プロジェクト: Gordiychuk/postgres
/*
 * scans posting tree and deletes empty pages
 */
static bool
ginScanToDelete(GinVacuumState *gvs, BlockNumber blkno, bool isRoot,
				DataPageDeleteStack *parent, OffsetNumber myoff)
{
	DataPageDeleteStack *me;
	Buffer		buffer;
	Page		page;
	bool		meDelete = FALSE;
	bool		isempty;

	if (isRoot)
	{
		me = parent;
	}
	else
	{
		if (!parent->child)
		{
			me = (DataPageDeleteStack *) palloc0(sizeof(DataPageDeleteStack));
			me->parent = parent;
			parent->child = me;
			me->leftBlkno = InvalidBlockNumber;
		}
		else
			me = parent->child;
	}

	buffer = ReadBufferExtended(gvs->index, MAIN_FORKNUM, blkno,
								RBM_NORMAL, gvs->strategy);
	page = BufferGetPage(buffer);

	Assert(GinPageIsData(page));

	if (!GinPageIsLeaf(page))
	{
		OffsetNumber i;

		me->blkno = blkno;
		for (i = FirstOffsetNumber; i <= GinPageGetOpaque(page)->maxoff; i++)
		{
			PostingItem *pitem = GinDataPageGetPostingItem(page, i);

			if (ginScanToDelete(gvs, PostingItemGetBlockNumber(pitem), FALSE, me, i))
				i--;
		}
	}

	if (GinPageIsLeaf(page))
		isempty = GinDataLeafPageIsEmpty(page);
	else
		isempty = GinPageGetOpaque(page)->maxoff < FirstOffsetNumber;

	if (isempty)
	{
		/* we never delete the left- or rightmost branch */
		if (me->leftBlkno != InvalidBlockNumber && !GinPageRightMost(page))
		{
			Assert(!isRoot);
			ginDeletePage(gvs, blkno, me->leftBlkno, me->parent->blkno, myoff, me->parent->isRoot);
			meDelete = TRUE;
		}
	}

	ReleaseBuffer(buffer);

	if (!meDelete)
		me->leftBlkno = blkno;

	return meDelete;
}
コード例 #19
0
ファイル: ginbtree.c プロジェクト: amulsul/postgres
/*
 * Try to find parent for current stack position, returns correct
 * parent and child's offset in  stack->parent.
 * Function should never release root page to prevent conflicts
 * with vacuum process
 */
void
ginFindParents(GinBtree btree, GinBtreeStack *stack,
			   BlockNumber rootBlkno)
{

	Page		page;
	Buffer		buffer;
	BlockNumber blkno,
				leftmostBlkno;
	OffsetNumber offset;
	GinBtreeStack *root = stack->parent;
	GinBtreeStack *ptr;

	if (!root)
	{
		/* XLog mode... */
		root = (GinBtreeStack *) palloc(sizeof(GinBtreeStack));
		root->blkno = rootBlkno;
		root->buffer = ReadBuffer(btree->index, rootBlkno);
		LockBuffer(root->buffer, GIN_EXCLUSIVE);
		root->parent = NULL;
	}
	else
	{
		/*
		 * find root, we should not release root page until update is
		 * finished!!
		 */
		while (root->parent)
		{
			ReleaseBuffer(root->buffer);
			root = root->parent;
		}

		Assert(root->blkno == rootBlkno);
		Assert(BufferGetBlockNumber(root->buffer) == rootBlkno);
		LockBuffer(root->buffer, GIN_EXCLUSIVE);
	}
	root->off = InvalidOffsetNumber;

	page = BufferGetPage(root->buffer);
	Assert(!GinPageIsLeaf(page));

	/* check trivial case */
	if ((root->off = btree->findChildPtr(btree, page, stack->blkno, InvalidOffsetNumber)) != InvalidOffsetNumber)
	{
		stack->parent = root;
		return;
	}

	leftmostBlkno = blkno = btree->getLeftMostPage(btree, page);
	LockBuffer(root->buffer, GIN_UNLOCK);
	Assert(blkno != InvalidBlockNumber);

	for (;;)
	{
		buffer = ReadBuffer(btree->index, blkno);
		LockBuffer(buffer, GIN_EXCLUSIVE);
		page = BufferGetPage(buffer);
		if (GinPageIsLeaf(page))
			elog(ERROR, "Lost path");

		leftmostBlkno = btree->getLeftMostPage(btree, page);

		while ((offset = btree->findChildPtr(btree, page, stack->blkno, InvalidOffsetNumber)) == InvalidOffsetNumber)
		{
			blkno = GinPageGetOpaque(page)->rightlink;
			LockBuffer(buffer, GIN_UNLOCK);
			ReleaseBuffer(buffer);
			if (blkno == InvalidBlockNumber)
				break;
			buffer = ReadBuffer(btree->index, blkno);
			LockBuffer(buffer, GIN_EXCLUSIVE);
			page = BufferGetPage(buffer);
		}

		if (blkno != InvalidBlockNumber)
		{
			ptr = (GinBtreeStack *) palloc(sizeof(GinBtreeStack));
			ptr->blkno = blkno;
			ptr->buffer = buffer;
			ptr->parent = root; /* it's may be wrong, but in next call we will
								 * correct */
			ptr->off = offset;
			stack->parent = ptr;
			return;
		}

		blkno = leftmostBlkno;
	}
}
コード例 #20
0
ファイル: wmv9mft.cpp プロジェクト: aracnoz/LAVFilters
STDMETHODIMP CDecWMV9MFT::ProcessOutput()
{
  HRESULT hr = S_OK;
  DWORD dwStatus = 0;

  MFT_OUTPUT_STREAM_INFO outputInfo = {0};
  m_pMFT->GetOutputStreamInfo(0, &outputInfo);

  IMFMediaBuffer *pMFBuffer = nullptr;
  ASSERT(!(outputInfo.dwFlags & MFT_OUTPUT_STREAM_PROVIDES_SAMPLES));

  MFT_OUTPUT_DATA_BUFFER OutputBuffer = {0};
  if (!(outputInfo.dwFlags & MFT_OUTPUT_STREAM_PROVIDES_SAMPLES)) {
    pMFBuffer = GetBuffer(outputInfo.cbSize);
    if (!pMFBuffer) { DbgLog((LOG_TRACE, 10, L"Unable to allocate media buffere")); return E_FAIL; }
  
    IMFSample *pSampleOut = nullptr;
    hr = MF.CreateSample(&pSampleOut);
    if (FAILED(hr)) { DbgLog((LOG_TRACE, 10, L"Unable to allocate MF sample, hr: 0x%x", hr)); ReleaseBuffer(pMFBuffer); return E_FAIL; }
    
    pSampleOut->AddBuffer(pMFBuffer);
    OutputBuffer.pSample = pSampleOut;
  }
  hr = m_pMFT->ProcessOutput(0, 1, &OutputBuffer, &dwStatus);

  // We don't process events, just release them
  SafeRelease(&OutputBuffer.pEvents);

  // handle stream format changes
  if (hr == MF_E_TRANSFORM_STREAM_CHANGE || OutputBuffer.dwStatus == MFT_OUTPUT_DATA_BUFFER_FORMAT_CHANGE ) {
    SafeRelease(&OutputBuffer.pSample);
    ReleaseBuffer(pMFBuffer);
    hr = SelectOutputType();
    if (FAILED(hr)) {
      DbgLog((LOG_TRACE, 10, L"-> Failed to handle stream change, hr: %x", hr));
      return E_FAIL;
    }
    // try again with the new type, it should work now!
    return ProcessOutput();
  }
  
  // the MFT generated no output, discard the sample and return
  if (hr == MF_E_TRANSFORM_NEED_MORE_INPUT || OutputBuffer.dwStatus == MFT_OUTPUT_DATA_BUFFER_NO_SAMPLE) {
    SafeRelease(&OutputBuffer.pSample);
    ReleaseBuffer(pMFBuffer);
    return S_FALSE;
  }
  
  // unknown error condition
  if (FAILED(hr)) {
    DbgLog((LOG_TRACE, 10, L"-> ProcessOutput failed with hr: %x", hr));
    SafeRelease(&OutputBuffer.pSample);
    ReleaseBuffer(pMFBuffer);
    return E_FAIL;
  }

  LAVFrame *pFrame = nullptr;
  AllocateFrame(&pFrame);

  IMFMediaType *pMTOut = nullptr;
  m_pMFT->GetOutputCurrentType(0, &pMTOut);

  MFGetAttributeSize(pMTOut, MF_MT_FRAME_SIZE, (UINT32 *)&pFrame->width, (UINT32 *)&pFrame->height);
  pFrame->format = m_OutPixFmt;

  AVRational pixel_aspect_ratio = {1, 1};
  MFGetAttributeRatio(pMTOut, MF_MT_PIXEL_ASPECT_RATIO, (UINT32*)&pixel_aspect_ratio.num, (UINT32*)&pixel_aspect_ratio.den);

  AVRational display_aspect_ratio = {0, 0};
  av_reduce(&display_aspect_ratio.num, &display_aspect_ratio.den, (int64_t)pixel_aspect_ratio.num * pFrame->width, (int64_t)pixel_aspect_ratio.den * pFrame->height, INT_MAX);

  pFrame->interlaced = MFGetAttributeUINT32(OutputBuffer.pSample, MFSampleExtension_Interlaced,       FALSE);
  pFrame->repeat     = MFGetAttributeUINT32(OutputBuffer.pSample, MFSampleExtension_RepeatFirstField, FALSE);

  LAVDeintFieldOrder fo = m_pSettings->GetDeintFieldOrder();
  pFrame->tff = (fo == DeintFieldOrder_Auto) ? !MFGetAttributeUINT32(OutputBuffer.pSample, MFSampleExtension_BottomFieldFirst, FALSE) : (fo == DeintFieldOrder_TopFieldFirst);

  if (pFrame->interlaced && !m_bInterlaced)
    m_bInterlaced = TRUE;

  pFrame->interlaced = (pFrame->interlaced || (m_bInterlaced && m_pSettings->GetDeinterlacingMode() == DeintMode_Aggressive) || m_pSettings->GetDeinterlacingMode() == DeintMode_Force) && !(m_pSettings->GetDeinterlacingMode() == DeintMode_Disable);

  pFrame->ext_format.VideoPrimaries         = MFGetAttributeUINT32(pMTOut, MF_MT_VIDEO_PRIMARIES,     MFVideoPrimaries_Unknown);
  pFrame->ext_format.VideoTransferFunction  = MFGetAttributeUINT32(pMTOut, MF_MT_TRANSFER_FUNCTION,   MFVideoTransFunc_Unknown);
  pFrame->ext_format.VideoTransferMatrix    = MFGetAttributeUINT32(pMTOut, MF_MT_YUV_MATRIX,          MFVideoTransferMatrix_Unknown);
  pFrame->ext_format.VideoChromaSubsampling = MFGetAttributeUINT32(pMTOut, MF_MT_VIDEO_CHROMA_SITING, MFVideoChromaSubsampling_Unknown);
  pFrame->ext_format.NominalRange           = MFGetAttributeUINT32(pMTOut, MF_MT_VIDEO_NOMINAL_RANGE, MFNominalRange_Unknown);

  // HACK: don't flag range=limited if its the only value set, since its also the implied default, this helps to avoid a reconnect
  // The MFT always sets this value, even if the bitstream says nothing about it, causing a reconnect on every vc1/wmv3 file
  if (pFrame->ext_format.value == 0x2000)
    pFrame->ext_format.value = 0;

  // Timestamps
  if (m_bManualReorder) {
    if (!m_timestampQueue.empty()) {
      pFrame->rtStart = m_timestampQueue.front();
      m_timestampQueue.pop();
      
      LONGLONG llDuration = 0;
      hr = OutputBuffer.pSample->GetSampleDuration(&llDuration);
      if (SUCCEEDED(hr) && llDuration > 0) {
        pFrame->rtStop = pFrame->rtStart + llDuration;
      }
    }
  } else {
    LONGLONG llTimestamp = 0;
    hr = OutputBuffer.pSample->GetSampleTime(&llTimestamp);
    if (SUCCEEDED(hr)) {
      pFrame->rtStart = llTimestamp;
      
      LONGLONG llDuration = 0;
      hr = OutputBuffer.pSample->GetSampleDuration(&llDuration);
      if (SUCCEEDED(hr) && llDuration > 0) {
        pFrame->rtStop = pFrame->rtStart + llDuration;
      }
    }
  }

  SafeRelease(&pMTOut);

  // Lock memory in the buffer
  BYTE *pBuffer = nullptr;
  pMFBuffer->Lock(&pBuffer, NULL, NULL);

  // Check alignment
  // If not properly aligned, we need to make the data aligned.
  int alignment = (m_OutPixFmt == LAVPixFmt_NV12) ? 16 : 32;
  if ((pFrame->width % alignment) != 0) {
    hr = AllocLAVFrameBuffers(pFrame);
    if (FAILED(hr)) {
      pMFBuffer->Unlock();
      ReleaseBuffer(pMFBuffer);
      SafeRelease(&OutputBuffer.pSample);
      return hr;
    }
    size_t ySize = pFrame->width * pFrame->height;
    
    memcpy_plane(pFrame->data[0], pBuffer, pFrame->width, pFrame->stride[0], pFrame->height);
    if (m_OutPixFmt == LAVPixFmt_NV12) {
      memcpy_plane(pFrame->data[1], pBuffer + ySize, pFrame->width, pFrame->stride[1], pFrame->height / 2);
    } else if (m_OutPixFmt == LAVPixFmt_YUV420) {
      size_t uvSize = ySize / 4;
      memcpy_plane(pFrame->data[2], pBuffer + ySize, pFrame->width / 2, pFrame->stride[2], pFrame->height / 2);
      memcpy_plane(pFrame->data[1], pBuffer + ySize + uvSize, pFrame->width / 2, pFrame->stride[1], pFrame->height / 2);
    }
    pMFBuffer->Unlock();
    ReleaseBuffer(pMFBuffer);
  } else {
    if (m_OutPixFmt == LAVPixFmt_NV12) {
      pFrame->data[0] = pBuffer;
      pFrame->data[1] = pBuffer + pFrame->width * pFrame->height;
      pFrame->stride[0] = pFrame->stride[1] = pFrame->width;
    } else if (m_OutPixFmt == LAVPixFmt_YUV420) {
      pFrame->data[0] = pBuffer;
      pFrame->data[2] = pBuffer + pFrame->width * pFrame->height;
      pFrame->data[1] = pFrame->data[2] + (pFrame->width / 2) * (pFrame->height / 2);
      pFrame->stride[0] = pFrame->width;
      pFrame->stride[1] = pFrame->stride[2] = pFrame->width / 2;
    }
    pFrame->data[3] = (BYTE *)pMFBuffer;
    pFrame->destruct = wmv9_buffer_destruct;
    pFrame->priv_data = this;
  }
  pFrame->flags |= LAV_FRAME_FLAG_BUFFER_MODIFY;
  Deliver(pFrame);

  SafeRelease(&OutputBuffer.pSample);

  if (OutputBuffer.dwStatus == MFT_OUTPUT_DATA_BUFFER_INCOMPLETE)
    return ProcessOutput();
  return hr;
}
コード例 #21
0
ファイル: cdbpersistentstore.c プロジェクト: LJoNe/gpdb
void PersistentStore_ReadTuple(
	PersistentStoreData 		*storeData,
	PersistentStoreSharedData 	*storeSharedData,
	ItemPointer					readTid,
	Datum						*values,
	HeapTuple					*tupleCopy)
{
	Relation	persistentRel;

	HeapTupleData 	tuple;
	Buffer			buffer;

	bool *nulls;
	
#ifdef USE_ASSERT_CHECKING
	if (storeSharedData == NULL ||
		!PersistentStoreSharedData_EyecatcherIsValid(storeSharedData))
		elog(ERROR, "Persistent store shared-memory not valid");
#endif
	
	if (Debug_persistent_store_print)
		elog(PersistentStore_DebugPrintLevel(), 
			 "PersistentStore_ReadTuple: Going to read tuple at TID %s ('%s', shared data %p)",
			 ItemPointerToString(readTid),
			 storeData->tableName,
			 storeSharedData);

	if (PersistentStore_IsZeroTid(readTid))
		elog(ERROR, "TID for fetch persistent tuple is invalid (0,0) ('%s')",
			 storeData->tableName);

	// UNDONE: I think the InRecovery test only applies to physical Master Mirroring on Standby.
	/* Only test this outside of recovery scenarios */
	if (!InRecovery 
		&& 
		(PersistentStore_IsZeroTid(&storeSharedData->maxTid)
		 ||
		 ItemPointerCompare(
						readTid,
						&storeSharedData->maxTid) == 1 // Greater-than.
		))
	{
		elog(ERROR, "TID %s for fetch persistent tuple is greater than the last known TID %s ('%s')",
			 ItemPointerToString(readTid),
			 ItemPointerToString2(&storeSharedData->maxTid),
			 storeData->tableName);
	}
	
	persistentRel = (*storeData->openRel)();

	tuple.t_self = *readTid;

	if (!heap_fetch(persistentRel, SnapshotAny,
					&tuple, &buffer, false, NULL))
	{
		elog(ERROR, "Failed to fetch persistent tuple at %s (maximum known TID %s, '%s')",
			 ItemPointerToString(&tuple.t_self),
			 ItemPointerToString2(&storeSharedData->maxTid),
			 storeData->tableName);
	}

	
	*tupleCopy = heaptuple_copy_to(&tuple, NULL, NULL);

	ReleaseBuffer(buffer);
	
	/*
	 * In order to keep the tuples the exact same size to enable direct reuse of
	 * free tuples, we do not use NULLs.
	 */
	nulls = (bool*)palloc(storeData->numAttributes * sizeof(bool));

	heap_deform_tuple(*tupleCopy, persistentRel->rd_att, values, nulls);

	(*storeData->closeRel)(persistentRel);
	
	if (Debug_persistent_store_print)
	{
		elog(PersistentStore_DebugPrintLevel(), 
			 "PersistentStore_ReadTuple: Successfully read tuple at TID %s ('%s')",
			 ItemPointerToString(readTid),
			 storeData->tableName);

		(*storeData->printTupleCallback)(
									PersistentStore_DebugPrintLevel(),
									"STORE READ TUPLE",
									readTid,
									values);
	}

	pfree(nulls);
}
コード例 #22
0
ファイル: iotjs_util.cpp プロジェクト: chunseoklee/iotjs_old
LocalString::~LocalString() {
  IOTJS_ASSERT(_strp != NULL);
  ReleaseBuffer(const_cast<char*>(_strp));
}
コード例 #23
0
/* ------------------------------------------------------
 * pgstatindex()
 *
 * Usage: SELECT * FROM pgstatindex('t1_pkey');
 * ------------------------------------------------------
 */
Datum
pgstatindex(PG_FUNCTION_ARGS)
{
	text	   *relname = PG_GETARG_TEXT_P(0);
	Relation	rel;
	RangeVar   *relrv;
	Datum		result;
	uint32		nblocks;
	uint32		blkno;
	BTIndexStat indexStat;

	if (!superuser())
		ereport(ERROR,
				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
				 (errmsg("must be superuser to use pgstattuple functions"))));

	relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
	rel = relation_openrv(relrv, AccessShareLock);

	if (!IS_INDEX(rel) || !IS_BTREE(rel))
		elog(ERROR, "pgstatindex() can be used only on b-tree index.");

	/*
	 * Reject attempts to read non-local temporary relations; we would
	 * be likely to get wrong data since we have no visibility into the
	 * owning session's local buffers.
	 */
	if (isOtherTempNamespace(RelationGetNamespace(rel)))
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("cannot access temporary tables of other sessions")));

	/*-------------------
	 * Read a metapage
	 *-------------------
	 */
	{
		Buffer		buffer = ReadBuffer(rel, 0);
		Page		page = BufferGetPage(buffer);
		BTMetaPageData *metad = BTPageGetMeta(page);

		indexStat.magic = metad->btm_magic;
		indexStat.version = metad->btm_version;
		indexStat.root_blkno = metad->btm_root;
		indexStat.level = metad->btm_level;
		indexStat.fastroot = metad->btm_fastroot;
		indexStat.fastlevel = metad->btm_fastlevel;

		ReleaseBuffer(buffer);
	}

	nblocks = RelationGetNumberOfBlocks(rel);

	/* -- init stat -- */
	indexStat.fragments = 0;

	indexStat.root_pages = 0;
	indexStat.leaf_pages = 0;
	indexStat.internal_pages = 0;
	indexStat.empty_pages = 0;
	indexStat.deleted_pages = 0;

	indexStat.max_avail = 0;
	indexStat.free_space = 0;

	/*-----------------------
	 * Scan all blocks
	 *-----------------------
	 */
	for (blkno = 1; blkno < nblocks; blkno++)
	{
		Buffer		buffer = ReadBuffer(rel, blkno);
		BTPageStat	stat;

		CHECK_FOR_INTERRUPTS();

		/* scan one page */
		stat.blkno = blkno;
		GetBTPageStatistics(blkno, buffer, &stat);

		/*---------------------
		 * page status (type)
		 *---------------------
		 */
		switch (stat.type)
		{
			case 'd':
				indexStat.deleted_pages++;
				break;
			case 'l':
				indexStat.leaf_pages++;
				break;
			case 'i':
				indexStat.internal_pages++;
				break;
			case 'e':
				indexStat.empty_pages++;
				break;
			case 'r':
				indexStat.root_pages++;
				break;
			default:
				elog(ERROR, "unknown page status.");
		}

		/* -- leaf fragmentation -- */
		indexStat.fragments += stat.fragments;

		if (stat.type == 'l')
		{
			indexStat.max_avail += stat.max_avail;
			indexStat.free_space += stat.free_size;
		}

		ReleaseBuffer(buffer);
	}

	relation_close(rel, AccessShareLock);

	/*----------------------------
	 * Build a result tuple
	 *----------------------------
	 */
	{
		TupleDesc	tupleDesc;
		int			j;
		char	   *values[PGSTATINDEX_NCOLUMNS];

		HeapTuple	tuple;

		tupleDesc = RelationNameGetTupleDesc(PGSTATINDEX_TYPE);

		j = 0;
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", indexStat.version);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", indexStat.level);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", (indexStat.root_pages +
										 indexStat.leaf_pages +
										 indexStat.internal_pages +
										 indexStat.deleted_pages +
										 indexStat.empty_pages) * BLCKSZ);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", indexStat.root_blkno);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", indexStat.internal_pages);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", indexStat.leaf_pages);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", indexStat.empty_pages);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", indexStat.deleted_pages);
		values[j] = palloc(32);
		if (indexStat.max_avail > 0)
			snprintf(values[j++], 32, "%.2f",
					 100.0 - (double) indexStat.free_space / (double) indexStat.max_avail * 100.0);
		else
			snprintf(values[j++], 32, "NaN");
		values[j] = palloc(32);
		if (indexStat.leaf_pages > 0)
			snprintf(values[j++], 32, "%.2f",
					 (double) indexStat.fragments / (double) indexStat.leaf_pages * 100.0);
		else
			snprintf(values[j++], 32, "NaN");

		tuple = BuildTupleFromCStrings(TupleDescGetAttInMetadata(tupleDesc),
									   values);

		result = TupleGetDatum(TupleDescGetSlot(tupleDesc), tuple);
	}

	PG_RETURN_DATUM(result);
}
コード例 #24
0
ファイル: indexscan.c プロジェクト: BenjaminYu/gpdb
Datum
readindex(PG_FUNCTION_ARGS)
{
	FuncCallContext	   *funcctx;
	readindexinfo	   *info;

	MIRROREDLOCK_BUFMGR_DECLARE;

	if (SRF_IS_FIRSTCALL())
	{
		Oid		irelid = PG_GETARG_OID(0);
		TupleDesc	tupdesc;
		MemoryContext oldcontext;
		AttrNumber		outattnum;
		Relation	irel;
		TupleDesc	itupdesc;
		int			i;
		AttrNumber	attno;

		irel = index_open(irelid, AccessShareLock);
		itupdesc = RelationGetDescr(irel);
		outattnum = FIXED_COLUMN + itupdesc->natts;

		funcctx = SRF_FIRSTCALL_INIT();
		oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
		tupdesc = CreateTemplateTupleDesc(outattnum, false);
		attno = 1;
		TupleDescInitEntry(tupdesc, attno++, "ictid", TIDOID, -1, 0);
		TupleDescInitEntry(tupdesc, attno++, "hctid", TIDOID, -1, 0);
		TupleDescInitEntry(tupdesc, attno++, "aotid", TEXTOID, -1, 0);
		TupleDescInitEntry(tupdesc, attno++, "istatus", TEXTOID, -1, 0);
		TupleDescInitEntry(tupdesc, attno++, "hstatus", TEXTOID, -1, 0);

		for (i = 0; i < itupdesc->natts; i++)
		{
			Form_pg_attribute attr = itupdesc->attrs[i];
			TupleDescInitEntry(tupdesc, attno++, NameStr(attr->attname), attr->atttypid, attr->atttypmod, 0);
		}

		funcctx->tuple_desc = BlessTupleDesc(tupdesc);
		info = (readindexinfo *) palloc(sizeof(readindexinfo));
		funcctx->user_fctx = (void *) info;

		info->outattnum = outattnum;
		info->irel = irel;
		info->hrel = relation_open(irel->rd_index->indrelid, AccessShareLock);
		if (info->hrel->rd_rel != NULL &&
				(info->hrel->rd_rel->relstorage == 'a' ||
				 info->hrel->rd_rel->relstorage == 'c'))
		{
			relation_close(info->hrel, AccessShareLock);
			info->hrel = NULL;
		}
		info->num_pages = RelationGetNumberOfBlocks(irel);
		info->blkno = BTREE_METAPAGE + 1;
		info->page = NULL;

		MemoryContextSwitchTo(oldcontext);
	}

	funcctx = SRF_PERCALL_SETUP();
	info = (readindexinfo *) funcctx->user_fctx;

	while (info->blkno < info->num_pages)
	{
		Datum		values[255];
		bool		nulls[255];
		ItemPointerData		itid;
		HeapTuple	tuple;
		Datum		result;

		if (info->page == NULL)
		{
			MIRROREDLOCK_BUFMGR_LOCK;
			info->buf = ReadBuffer(info->irel, info->blkno);
			info->page = BufferGetPage(info->buf);
			info->opaque = (BTPageOpaque) PageGetSpecialPointer(info->page);
			info->minoff = P_FIRSTDATAKEY(info->opaque);
			info->maxoff = PageGetMaxOffsetNumber(info->page);
			info->offnum = info->minoff;
			MIRROREDLOCK_BUFMGR_UNLOCK;
		}
		if (!P_ISLEAF(info->opaque) || info->offnum > info->maxoff)
		{
			ReleaseBuffer(info->buf);
			info->page = NULL;
			info->blkno++;
			continue;
		}

		MemSet(nulls, false, info->outattnum * sizeof(bool));

		ItemPointerSet(&itid, info->blkno, info->offnum);
		values[0] = ItemPointerGetDatum(&itid);
		readindextuple(info, values, nulls);

		info->offnum = OffsetNumberNext(info->offnum);

		tuple = heap_form_tuple(funcctx->tuple_desc, values, nulls);
		result = HeapTupleGetDatum(tuple);
		SRF_RETURN_NEXT(funcctx, result);
	}

	if (info->hrel != NULL)
		relation_close(info->hrel, AccessShareLock);
	index_close(info->irel, AccessShareLock);
	SRF_RETURN_DONE(funcctx);
}
コード例 #25
0
Datum
bt_page_items(PG_FUNCTION_ARGS)
{
	text	   *relname = PG_GETARG_TEXT_P(0);
	uint32		blkno = PG_GETARG_UINT32(1);

	RangeVar   *relrv;
	Datum		result;
	char	   *values[BTPAGEITEMS_NCOLUMNS];
	BTPageOpaque opaque;
	HeapTuple	tuple;
	ItemId		id;

	FuncCallContext *fctx;
	MemoryContext mctx;
	struct user_args *uargs = NULL;

	if (!superuser())
		ereport(ERROR,
				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
				 (errmsg("must be superuser to use pgstattuple functions"))));

	if (SRF_IS_FIRSTCALL())
	{
		fctx = SRF_FIRSTCALL_INIT();
		mctx = MemoryContextSwitchTo(fctx->multi_call_memory_ctx);

		uargs = palloc(sizeof(struct user_args));

		uargs->tupd = RelationNameGetTupleDesc(BTPAGEITEMS_TYPE);
		uargs->offset = FirstOffsetNumber;

		relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
		uargs->rel = relation_openrv(relrv, AccessShareLock);

		if (!IS_INDEX(uargs->rel) || !IS_BTREE(uargs->rel))
			elog(ERROR, "bt_page_items() can be used only on b-tree index.");

		/*
		 * Reject attempts to read non-local temporary relations; we would
		 * be likely to get wrong data since we have no visibility into the
		 * owning session's local buffers.
		 */
		if (isOtherTempNamespace(RelationGetNamespace(uargs->rel)))
			ereport(ERROR,
					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
					 errmsg("cannot access temporary tables of other sessions")));

		if (blkno == 0)
			elog(ERROR, "Block 0 is a meta page.");

		CHECK_RELATION_BLOCK_RANGE(uargs->rel, blkno);

		uargs->buffer = ReadBuffer(uargs->rel, blkno);

		uargs->page = BufferGetPage(uargs->buffer);

		opaque = (BTPageOpaque) PageGetSpecialPointer(uargs->page);

		if (P_ISDELETED(opaque))
			elog(NOTICE, "bt_page_items(): this page is deleted.");

		fctx->max_calls = PageGetMaxOffsetNumber(uargs->page);
		fctx->user_fctx = uargs;

		MemoryContextSwitchTo(mctx);
	}

	fctx = SRF_PERCALL_SETUP();
	uargs = fctx->user_fctx;

	if (fctx->call_cntr < fctx->max_calls)
	{
		IndexTuple	itup;

		id = PageGetItemId(uargs->page, uargs->offset);

		if (!ItemIdIsValid(id))
			elog(ERROR, "Invalid ItemId.");

		itup = (IndexTuple) PageGetItem(uargs->page, id);

		{
			int			j = 0;

			BlockNumber blkno = BlockIdGetBlockNumber(&(itup->t_tid.ip_blkid));

			values[j] = palloc(32);
			snprintf(values[j++], 32, "%d", uargs->offset);
			values[j] = palloc(32);
			snprintf(values[j++], 32, "(%u,%u)", blkno, itup->t_tid.ip_posid);
			values[j] = palloc(32);
			snprintf(values[j++], 32, "%d", (int) IndexTupleSize(itup));
			values[j] = palloc(32);
			snprintf(values[j++], 32, "%c", IndexTupleHasNulls(itup) ? 't' : 'f');
			values[j] = palloc(32);
			snprintf(values[j++], 32, "%c", IndexTupleHasVarwidths(itup) ? 't' : 'f');

			{
				int			off;
				char	   *dump;
				char	   *ptr = (char *) itup + IndexInfoFindDataOffset(itup->t_info);

				dump = palloc(IndexTupleSize(itup) * 3);
				memset(dump, 0, IndexTupleSize(itup) * 3);

				for (off = 0;
					 off < IndexTupleSize(itup) - IndexInfoFindDataOffset(itup->t_info);
					 off++)
				{
					if (dump[0] == '\0')
						sprintf(dump, "%02x", *(ptr + off) & 0xff);
					else
					{
						char		buf[4];

						sprintf(buf, " %02x", *(ptr + off) & 0xff);
						strcat(dump, buf);
					}
				}
				values[j] = dump;
			}

			tuple = BuildTupleFromCStrings(TupleDescGetAttInMetadata(uargs->tupd), values);
			result = TupleGetDatum(TupleDescGetSlot(uargs->tupd), tuple);
		}

		uargs->offset = uargs->offset + 1;

		SRF_RETURN_NEXT(fctx, result);
	}
	else
	{
		ReleaseBuffer(uargs->buffer);
		relation_close(uargs->rel, AccessShareLock);

		SRF_RETURN_DONE(fctx);
	}
}
コード例 #26
0
ファイル: ginfast.c プロジェクト: dividedmind/postgres
/*
 * Move tuples from pending pages into regular GIN structure.
 *
 * This can be called concurrently by multiple backends, so it must cope.
 * On first glance it looks completely not concurrent-safe and not crash-safe
 * either.  The reason it's okay is that multiple insertion of the same entry
 * is detected and treated as a no-op by gininsert.c.  If we crash after
 * posting entries to the main index and before removing them from the
 * pending list, it's okay because when we redo the posting later on, nothing
 * bad will happen.  Likewise, if two backends simultaneously try to post
 * a pending entry into the main index, one will succeed and one will do
 * nothing.  We try to notice when someone else is a little bit ahead of
 * us in the process, but that's just to avoid wasting cycles.  Only the
 * action of removing a page from the pending list really needs exclusive
 * lock.
 *
 * fill_fsm indicates that ginInsertCleanup should add deleted pages
 * to FSM otherwise caller is responsible to put deleted pages into
 * FSM.
 *
 * If stats isn't null, we count deleted pending pages into the counts.
 */
void
ginInsertCleanup(GinState *ginstate,
				 bool fill_fsm, IndexBulkDeleteResult *stats)
{
	Relation	index = ginstate->index;
	Buffer		metabuffer,
				buffer;
	Page		metapage,
				page;
	GinMetaPageData *metadata;
	MemoryContext opCtx,
				oldCtx;
	BuildAccumulator accum;
	KeyArray	datums;
	BlockNumber blkno;
	bool		fsm_vac = false;

	metabuffer = ReadBuffer(index, GIN_METAPAGE_BLKNO);
	LockBuffer(metabuffer, GIN_SHARE);
	metapage = BufferGetPage(metabuffer);
	metadata = GinPageGetMeta(metapage);

	if (metadata->head == InvalidBlockNumber)
	{
		/* Nothing to do */
		UnlockReleaseBuffer(metabuffer);
		return;
	}

	/*
	 * Read and lock head of pending list
	 */
	blkno = metadata->head;
	buffer = ReadBuffer(index, blkno);
	LockBuffer(buffer, GIN_SHARE);
	page = BufferGetPage(buffer);

	LockBuffer(metabuffer, GIN_UNLOCK);

	/*
	 * Initialize.  All temporary space will be in opCtx
	 */
	opCtx = AllocSetContextCreate(CurrentMemoryContext,
								  "GIN insert cleanup temporary context",
								  ALLOCSET_DEFAULT_MINSIZE,
								  ALLOCSET_DEFAULT_INITSIZE,
								  ALLOCSET_DEFAULT_MAXSIZE);

	oldCtx = MemoryContextSwitchTo(opCtx);

	initKeyArray(&datums, 128);
	ginInitBA(&accum);
	accum.ginstate = ginstate;

	/*
	 * At the top of this loop, we have pin and lock on the current page of
	 * the pending list.  However, we'll release that before exiting the loop.
	 * Note we also have pin but not lock on the metapage.
	 */
	for (;;)
	{
		if (GinPageIsDeleted(page))
		{
			/* another cleanup process is running concurrently */
			UnlockReleaseBuffer(buffer);
			fsm_vac = false;
			break;
		}

		/*
		 * read page's datums into accum
		 */
		processPendingPage(&accum, &datums, page, FirstOffsetNumber);

		vacuum_delay_point();

		/*
		 * Is it time to flush memory to disk?	Flush if we are at the end of
		 * the pending list, or if we have a full row and memory is getting
		 * full.
		 *
		 * XXX using up maintenance_work_mem here is probably unreasonably
		 * much, since vacuum might already be using that much.
		 */
		if (GinPageGetOpaque(page)->rightlink == InvalidBlockNumber ||
			(GinPageHasFullRow(page) &&
			 (accum.allocatedMemory >= (Size)maintenance_work_mem * 1024L)))
		{
			ItemPointerData *list;
			uint32		nlist;
			Datum		key;
			GinNullCategory category;
			OffsetNumber maxoff,
						attnum;

			/*
			 * Unlock current page to increase performance. Changes of page
			 * will be checked later by comparing maxoff after completion of
			 * memory flush.
			 */
			maxoff = PageGetMaxOffsetNumber(page);
			LockBuffer(buffer, GIN_UNLOCK);

			/*
			 * Moving collected data into regular structure can take
			 * significant amount of time - so, run it without locking pending
			 * list.
			 */
			ginBeginBAScan(&accum);
			while ((list = ginGetBAEntry(&accum,
								  &attnum, &key, &category, &nlist)) != NULL)
			{
				ginEntryInsert(ginstate, attnum, key, category,
							   list, nlist, NULL);
				vacuum_delay_point();
			}

			/*
			 * Lock the whole list to remove pages
			 */
			LockBuffer(metabuffer, GIN_EXCLUSIVE);
			LockBuffer(buffer, GIN_SHARE);

			if (GinPageIsDeleted(page))
			{
				/* another cleanup process is running concurrently */
				UnlockReleaseBuffer(buffer);
				LockBuffer(metabuffer, GIN_UNLOCK);
				fsm_vac = false;
				break;
			}

			/*
			 * While we left the page unlocked, more stuff might have gotten
			 * added to it.  If so, process those entries immediately.  There
			 * shouldn't be very many, so we don't worry about the fact that
			 * we're doing this with exclusive lock. Insertion algorithm
			 * guarantees that inserted row(s) will not continue on next page.
			 * NOTE: intentionally no vacuum_delay_point in this loop.
			 */
			if (PageGetMaxOffsetNumber(page) != maxoff)
			{
				ginInitBA(&accum);
				processPendingPage(&accum, &datums, page, maxoff + 1);

				ginBeginBAScan(&accum);
				while ((list = ginGetBAEntry(&accum,
								  &attnum, &key, &category, &nlist)) != NULL)
					ginEntryInsert(ginstate, attnum, key, category,
								   list, nlist, NULL);
			}

			/*
			 * Remember next page - it will become the new list head
			 */
			blkno = GinPageGetOpaque(page)->rightlink;
			UnlockReleaseBuffer(buffer);		/* shiftList will do exclusive
												 * locking */

			/*
			 * remove read pages from pending list, at this point all
			 * content of read pages is in regular structure
			 */
			if (shiftList(index, metabuffer, blkno, fill_fsm, stats))
			{
				/* another cleanup process is running concurrently */
				LockBuffer(metabuffer, GIN_UNLOCK);
				fsm_vac = false;
				break;
			}

			/* At this point, some pending pages have been freed up */
			fsm_vac = true;

			Assert(blkno == metadata->head);
			LockBuffer(metabuffer, GIN_UNLOCK);

			/*
			 * if we removed the whole pending list just exit
			 */
			if (blkno == InvalidBlockNumber)
				break;

			/*
			 * release memory used so far and reinit state
			 */
			MemoryContextReset(opCtx);
			initKeyArray(&datums, datums.maxvalues);
			ginInitBA(&accum);
		}
		else
		{
			blkno = GinPageGetOpaque(page)->rightlink;
			UnlockReleaseBuffer(buffer);
		}

		/*
		 * Read next page in pending list
		 */
		vacuum_delay_point();
		buffer = ReadBuffer(index, blkno);
		LockBuffer(buffer, GIN_SHARE);
		page = BufferGetPage(buffer);
	}

	ReleaseBuffer(metabuffer);

	/*
	 * As pending list pages can have a high churn rate, it is
	 * desirable to recycle them immediately to the FreeSpace Map when
	 * ordinary backends clean the list.
	 */
	if (fsm_vac && fill_fsm)
		IndexFreeSpaceMapVacuum(index);


	/* Clean up temporary space */
	MemoryContextSwitchTo(oldCtx);
	MemoryContextDelete(opCtx);
}
コード例 #27
0
ファイル: freespace.c プロジェクト: Gordiychuk/postgres
/*
 * Recursive guts of FreeSpaceMapVacuum
 */
static uint8
fsm_vacuum_page(Relation rel, FSMAddress addr, bool *eof_p)
{
	Buffer		buf;
	Page		page;
	uint8		max_avail;

	/* Read the page if it exists, or return EOF */
	buf = fsm_readbuf(rel, addr, false);
	if (!BufferIsValid(buf))
	{
		*eof_p = true;
		return 0;
	}
	else
		*eof_p = false;

	page = BufferGetPage(buf);

	/*
	 * Recurse into children, and fix the information stored about them at
	 * this level.
	 */
	if (addr.level > FSM_BOTTOM_LEVEL)
	{
		int			slot;
		bool		eof = false;

		for (slot = 0; slot < SlotsPerFSMPage; slot++)
		{
			int			child_avail;

			CHECK_FOR_INTERRUPTS();

			/* After we hit end-of-file, just clear the rest of the slots */
			if (!eof)
				child_avail = fsm_vacuum_page(rel, fsm_get_child(addr, slot), &eof);
			else
				child_avail = 0;

			/* Update information about the child */
			if (fsm_get_avail(page, slot) != child_avail)
			{
				LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);
				fsm_set_avail(BufferGetPage(buf), slot, child_avail);
				MarkBufferDirtyHint(buf, false);
				LockBuffer(buf, BUFFER_LOCK_UNLOCK);
			}
		}
	}

	max_avail = fsm_get_max_avail(BufferGetPage(buf));

	/*
	 * Reset the next slot pointer. This encourages the use of low-numbered
	 * pages, increasing the chances that a later vacuum can truncate the
	 * relation.
	 */
	((FSMPage) PageGetContents(page))->fp_next_slot = 0;

	ReleaseBuffer(buf);

	return max_avail;
}
コード例 #28
0
FarString& FarString::TrimLeft()
{
  FarSF::LTrim (GetBuffer());
  ReleaseBuffer();
  return * this;
}
コード例 #29
0
ファイル: execTuples.c プロジェクト: qiuyesuifeng/gpdb
/* --------------------------------
 *		ExecStoreTuple
 *
 *		This function is used to store a physical tuple into a specified
 *		slot in the tuple table.
 *
 *		tuple:	tuple to store
 *		slot:	slot to store it in
 *		buffer: disk buffer if tuple is in a disk page, else InvalidBuffer
 *		shouldFree: true if ExecClearTuple should pfree() the tuple
 *					when done with it
 *
 * If 'buffer' is not InvalidBuffer, the tuple table code acquires a pin
 * on the buffer which is held until the slot is cleared, so that the tuple
 * won't go away on us.
 *
 * shouldFree is normally set 'true' for tuples constructed on-the-fly.
 * It must always be 'false' for tuples that are stored in disk pages,
 * since we don't want to try to pfree those.
 *
 * Another case where it is 'false' is when the referenced tuple is held
 * in a tuple table slot belonging to a lower-level executor Proc node.
 * In this case the lower-level slot retains ownership and responsibility
 * for eventually releasing the tuple.	When this method is used, we must
 * be certain that the upper-level Proc node will lose interest in the tuple
 * sooner than the lower-level one does!  If you're not certain, copy the
 * lower-level tuple with heap_copytuple and let the upper-level table
 * slot assume ownership of the copy!
 *
 * Return value is just the passed-in slot pointer.
 *
 * NOTE: before PostgreSQL 8.1, this function would accept a NULL tuple
 * pointer and effectively behave like ExecClearTuple (though you could
 * still specify a buffer to pin, which would be an odd combination).
 * This saved a couple lines of code in a few places, but seemed more likely
 * to mask logic errors than to be really useful, so it's now disallowed.
 * --------------------------------
 */
TupleTableSlot *
ExecStoreHeapTuple(HeapTuple tuple,
			   TupleTableSlot *slot,
			   Buffer buffer,
			   bool shouldFree)
{
	/*
	 * sanity checks
	 */
	Assert(tuple != NULL);
	Assert(slot != NULL);
	Assert(slot->tts_tupleDescriptor != NULL);
	/* passing shouldFree=true for a tuple on a disk page is not sane */
	Assert(BufferIsValid(buffer) ? (!shouldFree) : true);

	/*
	 * Actually we are storing a memtuple!
	 */
	if(is_heaptuple_memtuple(tuple))
	{
		Assert(buffer == InvalidBuffer);
		return ExecStoreMemTuple((MemTuple) tuple, slot, shouldFree);
	}

	/*
	 * Free any old physical tuple belonging to the slot.
	 */
	free_heaptuple_memtuple(slot);

	/*
	 * Store the new tuple into the specified slot.
	 */

	/* Clear tts_flags, here isempty set to false */
	slot->PRIVATE_tts_flags = shouldFree ? TTS_SHOULDFREE : 0;

	/* store the tuple */
	slot->PRIVATE_tts_heaptuple = (void *) tuple;

	/* Mark extracted state invalid */
	slot->PRIVATE_tts_nvalid = 0;

	/*
	 * If tuple is on a disk page, keep the page pinned as long as we hold a
	 * pointer into it.  We assume the caller already has such a pin.
	 *
	 * This is coded to optimize the case where the slot previously held a
	 * tuple on the same disk page: in that case releasing and re-acquiring
	 * the pin is a waste of cycles.  This is a common situation during
	 * seqscans, so it's worth troubling over.
	 */
	if (slot->tts_buffer != buffer)
	{
		if (BufferIsValid(slot->tts_buffer))
			ReleaseBuffer(slot->tts_buffer);
		slot->tts_buffer = buffer;
		if (BufferIsValid(buffer))
			IncrBufferRefCount(buffer);
	}

	return slot;
}
コード例 #30
0
/* ------------------------------------------------------
 * pgstatindex()
 *
 * Usage: SELECT * FROM pgstatindex('t1_pkey');
 * ------------------------------------------------------
 */
Datum
pgstatindex(PG_FUNCTION_ARGS)
{
	text	   *relname = PG_GETARG_TEXT_P(0);
	Relation	rel;
	RangeVar   *relrv;
	Datum		result;
	BlockNumber nblocks;
	BlockNumber blkno;
	BTIndexStat indexStat;

	if (!superuser())
		ereport(ERROR,
				(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
				 (errmsg("must be superuser to use pgstattuple functions"))));

	relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
	rel = relation_openrv(relrv, AccessShareLock);

	if (!IS_INDEX(rel) || !IS_BTREE(rel))
		elog(ERROR, "relation \"%s\" is not a btree index",
			 RelationGetRelationName(rel));

	/*
	 * Reject attempts to read non-local temporary relations; we would be
	 * likely to get wrong data since we have no visibility into the owning
	 * session's local buffers.
	 */
	if (RELATION_IS_OTHER_TEMP(rel))
		ereport(ERROR,
				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
				 errmsg("cannot access temporary tables of other sessions")));

	/*
	 * Read metapage
	 */
	{
		Buffer		buffer = ReadBuffer(rel, 0);
		Page		page = BufferGetPage(buffer);
		BTMetaPageData *metad = BTPageGetMeta(page);

		indexStat.version = metad->btm_version;
		indexStat.level = metad->btm_level;
		indexStat.root_blkno = metad->btm_root;

		ReleaseBuffer(buffer);
	}

	/* -- init counters -- */
	indexStat.root_pages = 0;
	indexStat.internal_pages = 0;
	indexStat.leaf_pages = 0;
	indexStat.empty_pages = 0;
	indexStat.deleted_pages = 0;

	indexStat.max_avail = 0;
	indexStat.free_space = 0;

	indexStat.fragments = 0;

	/*
	 * Scan all blocks except the metapage
	 */
	nblocks = RelationGetNumberOfBlocks(rel);

	for (blkno = 1; blkno < nblocks; blkno++)
	{
		Buffer		buffer;
		Page		page;
		BTPageOpaque opaque;

		/* Read and lock buffer */
		buffer = ReadBuffer(rel, blkno);
		LockBuffer(buffer, BUFFER_LOCK_SHARE);

		page = BufferGetPage(buffer);
		opaque = (BTPageOpaque) PageGetSpecialPointer(page);

		/* Determine page type, and update totals */

		if (P_ISLEAF(opaque))
		{
			int			max_avail;

			max_avail = BLCKSZ - (BLCKSZ - ((PageHeader) page)->pd_special + SizeOfPageHeaderData);
			indexStat.max_avail += max_avail;
			indexStat.free_space += PageGetFreeSpace(page);

			indexStat.leaf_pages++;

			/*
			 * If the next leaf is on an earlier block, it means a
			 * fragmentation.
			 */
			if (opaque->btpo_next != P_NONE && opaque->btpo_next < blkno)
				indexStat.fragments++;
		}
		else if (P_ISDELETED(opaque))
			indexStat.deleted_pages++;
		else if (P_IGNORE(opaque))
			indexStat.empty_pages++;
		else if (P_ISROOT(opaque))
			indexStat.root_pages++;
		else
			indexStat.internal_pages++;

		/* Unlock and release buffer */
		LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
		ReleaseBuffer(buffer);
	}

	relation_close(rel, AccessShareLock);

	/*----------------------------
	 * Build a result tuple
	 *----------------------------
	 */
	{
		TupleDesc	tupleDesc;
		int			j;
		char	   *values[10];
		HeapTuple	tuple;

		/* Build a tuple descriptor for our result type */
		if (get_call_result_type(fcinfo, NULL, &tupleDesc) != TYPEFUNC_COMPOSITE)
			elog(ERROR, "return type must be a row type");

		j = 0;
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", indexStat.version);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%d", indexStat.level);
		values[j] = palloc(32);
		snprintf(values[j++], 32, INT64_FORMAT,
				 (indexStat.root_pages +
				  indexStat.leaf_pages +
				  indexStat.internal_pages +
				  indexStat.deleted_pages +
				  indexStat.empty_pages) * BLCKSZ);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%u", indexStat.root_blkno);
		values[j] = palloc(32);
		snprintf(values[j++], 32, INT64_FORMAT, indexStat.internal_pages);
		values[j] = palloc(32);
		snprintf(values[j++], 32, INT64_FORMAT, indexStat.leaf_pages);
		values[j] = palloc(32);
		snprintf(values[j++], 32, INT64_FORMAT, indexStat.empty_pages);
		values[j] = palloc(32);
		snprintf(values[j++], 32, INT64_FORMAT, indexStat.deleted_pages);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%.2f", 100.0 - (double) indexStat.free_space / (double) indexStat.max_avail * 100.0);
		values[j] = palloc(32);
		snprintf(values[j++], 32, "%.2f", (double) indexStat.fragments / (double) indexStat.leaf_pages * 100.0);

		tuple = BuildTupleFromCStrings(TupleDescGetAttInMetadata(tupleDesc),
									   values);

		result = HeapTupleGetDatum(tuple);
	}

	PG_RETURN_DATUM(result);
}