1 files changed, 1 insertions, 155 deletions

diff --git a/src/backend/access/nbtree/nbtxlog.c b/src/backend/access/nbtree/nbtxlog.c
index ff262ff5c9a..dd5f54eb2d2 100644
--- a/src/backend/access/nbtree/nbtxlog.c
+++ b/src/backend/access/nbtree/nbtxlog.c
@@ -501,159 +501,6 @@ btree_xlog_vacuum(XLogReaderState *record)
 		UnlockReleaseBuffer(buffer);
 }
 
-/*
- * Get the latestRemovedXid from the heap pages pointed at by the index
- * tuples being deleted. This puts the work for calculating latestRemovedXid
- * into the recovery path rather than the primary path.
- *
- * It's possible that this generates a fair amount of I/O, since an index
- * block may have hundreds of tuples being deleted. Repeat accesses to the
- * same heap blocks are common, though are not yet optimised.
- *
- * XXX optimise later with something like XLogPrefetchBuffer()
- */
-static TransactionId
-btree_xlog_delete_get_latestRemovedXid(XLogReaderState *record)
-{
-	xl_btree_delete *xlrec = (xl_btree_delete *) XLogRecGetData(record);
-	OffsetNumber *unused;
-	Buffer		ibuffer,
-				hbuffer;
-	Page		ipage,
-				hpage;
-	RelFileNode rnode;
-	BlockNumber blkno;
-	ItemId		iitemid,
-				hitemid;
-	IndexTuple	itup;
-	HeapTupleHeader htuphdr;
-	BlockNumber hblkno;
-	OffsetNumber hoffnum;
-	TransactionId latestRemovedXid = InvalidTransactionId;
-	int			i;
-
-	/*
-	 * If there's nothing running on the standby we don't need to derive a
-	 * full latestRemovedXid value, so use a fast path out of here.  This
-	 * returns InvalidTransactionId, and so will conflict with all HS
-	 * transactions; but since we just worked out that that's zero people,
-	 * it's OK.
-	 *
-	 * XXX There is a race condition here, which is that a new backend might
-	 * start just after we look.  If so, it cannot need to conflict, but this
-	 * coding will result in throwing a conflict anyway.
-	 */
-	if (CountDBBackends(InvalidOid) == 0)
-		return latestRemovedXid;
-
-	/*
-	 * In what follows, we have to examine the previous state of the index
-	 * page, as well as the heap page(s) it points to.  This is only valid if
-	 * WAL replay has reached a consistent database state; which means that
-	 * the preceding check is not just an optimization, but is *necessary*. We
-	 * won't have let in any user sessions before we reach consistency.
-	 */
-	if (!reachedConsistency)
-		elog(PANIC, "btree_xlog_delete_get_latestRemovedXid: cannot operate with inconsistent data");
-
-	/*
-	 * Get index page.  If the DB is consistent, this should not fail, nor
-	 * should any of the heap page fetches below.  If one does, we return
-	 * InvalidTransactionId to cancel all HS transactions.  That's probably
-	 * overkill, but it's safe, and certainly better than panicking here.
-	 */
-	XLogRecGetBlockTag(record, 0, &rnode, NULL, &blkno);
-	ibuffer = XLogReadBufferExtended(rnode, MAIN_FORKNUM, blkno, RBM_NORMAL);
-	if (!BufferIsValid(ibuffer))
-		return InvalidTransactionId;
-	LockBuffer(ibuffer, BT_READ);
-	ipage = (Page) BufferGetPage(ibuffer);
-
-	/*
-	 * Loop through the deleted index items to obtain the TransactionId from
-	 * the heap items they point to.
-	 */
-	unused = (OffsetNumber *) ((char *) xlrec + SizeOfBtreeDelete);
-
-	for (i = 0; i < xlrec->nitems; i++)
-	{
-		/*
-		 * Identify the index tuple about to be deleted
-		 */
-		iitemid = PageGetItemId(ipage, unused[i]);
-		itup = (IndexTuple) PageGetItem(ipage, iitemid);
-
-		/*
-		 * Locate the heap page that the index tuple points at
-		 */
-		hblkno = ItemPointerGetBlockNumber(&(itup->t_tid));
-		hbuffer = XLogReadBufferExtended(xlrec->hnode, MAIN_FORKNUM, hblkno, RBM_NORMAL);
-		if (!BufferIsValid(hbuffer))
-		{
-			UnlockReleaseBuffer(ibuffer);
-			return InvalidTransactionId;
-		}
-		LockBuffer(hbuffer, BT_READ);
-		hpage = (Page) BufferGetPage(hbuffer);
-
-		/*
-		 * Look up the heap tuple header that the index tuple points at by
-		 * using the heap node supplied with the xlrec. We can't use
-		 * heap_fetch, since it uses ReadBuffer rather than XLogReadBuffer.
-		 * Note that we are not looking at tuple data here, just headers.
-		 */
-		hoffnum = ItemPointerGetOffsetNumber(&(itup->t_tid));
-		hitemid = PageGetItemId(hpage, hoffnum);
-
-		/*
-		 * Follow any redirections until we find something useful.
-		 */
-		while (ItemIdIsRedirected(hitemid))
-		{
-			hoffnum = ItemIdGetRedirect(hitemid);
-			hitemid = PageGetItemId(hpage, hoffnum);
-			CHECK_FOR_INTERRUPTS();
-		}
-
-		/*
-		 * If the heap item has storage, then read the header and use that to
-		 * set latestRemovedXid.
-		 *
-		 * Some LP_DEAD items may not be accessible, so we ignore them.
-		 */
-		if (ItemIdHasStorage(hitemid))
-		{
-			htuphdr = (HeapTupleHeader) PageGetItem(hpage, hitemid);
-
-			HeapTupleHeaderAdvanceLatestRemovedXid(htuphdr, &latestRemovedXid);
-		}
-		else if (ItemIdIsDead(hitemid))
-		{
-			/*
-			 * Conjecture: if hitemid is dead then it had xids before the xids
-			 * marked on LP_NORMAL items. So we just ignore this item and move
-			 * onto the next, for the purposes of calculating
-			 * latestRemovedxids.
-			 */
-		}
-		else
-			Assert(!ItemIdIsUsed(hitemid));
-
-		UnlockReleaseBuffer(hbuffer);
-	}
-
-	UnlockReleaseBuffer(ibuffer);
-
-	/*
-	 * If all heap tuples were LP_DEAD then we will be returning
-	 * InvalidTransactionId here, which avoids conflicts. This matches
-	 * existing logic which assumes that LP_DEAD tuples must already be older
-	 * than the latestRemovedXid on the cleanup record that set them as
-	 * LP_DEAD, hence must already have generated a conflict.
-	 */
-	return latestRemovedXid;
-}
-
 static void
 btree_xlog_delete(XLogReaderState *record)
 {
@@ -676,12 +523,11 @@ btree_xlog_delete(XLogReaderState *record)
 	 */
 	if (InHotStandby)
 	{
-		TransactionId latestRemovedXid = btree_xlog_delete_get_latestRemovedXid(record);
 		RelFileNode rnode;
 
 		XLogRecGetBlockTag(record, 0, &rnode, NULL, NULL);
 
-		ResolveRecoveryConflictWithSnapshot(latestRemovedXid, rnode);
+		ResolveRecoveryConflictWithSnapshot(xlrec->latestRemovedXid, rnode);
 	}
 
 	/*