Esempio n. 1
0
/*
 *	visibilitymap_set - set a bit on a previously pinned page
 *
 * recptr is the LSN of the XLOG record we're replaying, if we're in recovery,
 * or InvalidXLogRecPtr in normal running.  The page LSN is advanced to the
 * one provided; in normal running, we generate a new XLOG record and set the
 * page LSN to that value.  cutoff_xid is the largest xmin on the page being
 * marked all-visible; it is needed for Hot Standby, and can be
 * InvalidTransactionId if the page contains no tuples.
 *
 * You must pass a buffer containing the correct map page to this function.
 * Call visibilitymap_pin first to pin the right one. This function doesn't do
 * any I/O.
 */
void
visibilitymap_set(Relation rel, BlockNumber heapBlk, XLogRecPtr recptr,
				  Buffer buf, TransactionId cutoff_xid)
{
	BlockNumber mapBlock = HEAPBLK_TO_MAPBLOCK(heapBlk);
	uint32		mapByte = HEAPBLK_TO_MAPBYTE(heapBlk);
	uint8		mapBit = HEAPBLK_TO_MAPBIT(heapBlk);
	Page		page;
	char	   *map;

#ifdef TRACE_VISIBILITYMAP
	elog(DEBUG1, "vm_set %s %d", RelationGetRelationName(rel), heapBlk);
#endif

	Assert(InRecovery || XLogRecPtrIsInvalid(recptr));

	/* Check that we have the right page pinned */
	if (!BufferIsValid(buf) || BufferGetBlockNumber(buf) != mapBlock)
		elog(ERROR, "wrong buffer passed to visibilitymap_set");

	page = BufferGetPage(buf);
	map = PageGetContents(page);
	LockBuffer(buf, BUFFER_LOCK_EXCLUSIVE);

	if (!(map[mapByte] & (1 << mapBit)))
	{
		START_CRIT_SECTION();

		map[mapByte] |= (1 << mapBit);
		MarkBufferDirty(buf);

		if (RelationNeedsWAL(rel))
		{
			if (XLogRecPtrIsInvalid(recptr))
				recptr = log_heap_visible(rel->rd_node, heapBlk, buf,
										  cutoff_xid);
			PageSetLSN(page, recptr);
			PageSetTLI(page, ThisTimeLineID);
		}

		END_CRIT_SECTION();
	}

	LockBuffer(buf, BUFFER_LOCK_UNLOCK);
}
Esempio n. 2
0
/*
 *	visibilitymap_set - set a bit on a previously pinned page
 *
 * recptr is the LSN of the XLOG record we're replaying, if we're in recovery,
 * or InvalidXLogRecPtr in normal running.  The page LSN is advanced to the
 * one provided; in normal running, we generate a new___ XLOG record and set the
 * page LSN to that value.  cutoff_xid is the largest xmin on the page being
 * marked all-visible; it is needed for Hot Standby, and can be
 * InvalidTransactionId if the page contains no tuples.
 *
 * Caller is expected to set the heap page's PD_ALL_VISIBLE bit before calling
 * this function. Except in recovery, caller should also pass the heap
 * buffer. When checksums are enabled and we're not in recovery, we must add
 * the heap buffer to the WAL chain to protect it from being torn.
 *
 * You must pass a buffer containing the correct map page to this function.
 * Call visibilitymap_pin first to pin the right one. This function doesn't do
 * any I/O.
 */
void
visibilitymap_set(Relation rel, BlockNumber heapBlk, Buffer heapBuf,
				  XLogRecPtr recptr, Buffer vmBuf, TransactionId cutoff_xid)
{
	BlockNumber mapBlock = HEAPBLK_TO_MAPBLOCK(heapBlk);
	uint32		mapByte = HEAPBLK_TO_MAPBYTE(heapBlk);
	uint8		mapBit = HEAPBLK_TO_MAPBIT(heapBlk);
	Page		page;
	char	   *map;

#ifdef TRACE_VISIBILITYMAP
	elog(DEBUG1, "vm_set %s %d", RelationGetRelationName(rel), heapBlk);
#endif

	Assert(InRecovery || XLogRecPtrIsInvalid(recptr));
	Assert(InRecovery || BufferIsValid(heapBuf));

	/* Check that we have the right heap page pinned, if present */
	if (BufferIsValid(heapBuf) && BufferGetBlockNumber(heapBuf) != heapBlk)
		elog(ERROR, "wrong heap buffer passed to visibilitymap_set");

	/* Check that we have the right VM page pinned */
	if (!BufferIsValid(vmBuf) || BufferGetBlockNumber(vmBuf) != mapBlock)
		elog(ERROR, "wrong VM buffer passed to visibilitymap_set");

	page = BufferGetPage(vmBuf);
	map = PageGetContents(page);
	LockBuffer(vmBuf, BUFFER_LOCK_EXCLUSIVE);

	if (!(map[mapByte] & (1 << mapBit)))
	{
		START_CRIT_SECTION();

		map[mapByte] |= (1 << mapBit);
		MarkBufferDirty(vmBuf);

		if (RelationNeedsWAL(rel))
		{
			if (XLogRecPtrIsInvalid(recptr))
			{
				Assert(!InRecovery);
				recptr = log_heap_visible(rel->rd_node, heapBuf, vmBuf,
										  cutoff_xid);

				/*
				 * If data checksums are enabled (or wal_log_hints=on), we
				 * need to protect the heap page from being torn.
				 */
				if (XLogHintBitIsNeeded())
				{
					Page		heapPage = BufferGetPage(heapBuf);

					/* caller is expected to set PD_ALL_VISIBLE first */
					Assert(PageIsAllVisible(heapPage));
					PageSetLSN(heapPage, recptr);
				}
			}
			PageSetLSN(page, recptr);
		}

		END_CRIT_SECTION();
	}

	LockBuffer(vmBuf, BUFFER_LOCK_UNLOCK);
}