Modify XLogInsert API to make callers specify whether pages to be backed

up have the standard layout with unused space between pd_lower and pd_upper.
When this is set, XLogInsert will omit the unused space without bothering
to scan it to see if it's zero.  That saves time in XLogInsert, and also
allows reversion of my earlier patch to make PageRepairFragmentation et al
explicitly re-zero freed space.  Per suggestion by Heikki Linnakangas.

1 files changed, 11 insertions, 9 deletions

diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c
index 868a91ab3a5..9b9fa44e6ed 100644
--- a/src/backend/access/nbtree/nbtinsert.c
+++ b/src/backend/access/nbtree/nbtinsert.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.120 2005/03/21 01:23:59 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.121 2005/06/06 20:22:57 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -564,9 +564,9 @@ _bt_insertonpg(Relation rel,
 			xlrec.target.node = rel->rd_node;
 			ItemPointerSet(&(xlrec.target.tid), itup_blkno, itup_off);
 
-			rdata[0].buffer = InvalidBuffer;
 			rdata[0].data = (char *) &xlrec;
 			rdata[0].len = SizeOfBtreeInsert;
+			rdata[0].buffer = InvalidBuffer;
 			rdata[0].next = nextrdata = &(rdata[1]);
 
 			if (BufferIsValid(metabuf))
@@ -576,9 +576,9 @@ _bt_insertonpg(Relation rel,
 				xlmeta.fastroot = metad->btm_fastroot;
 				xlmeta.fastlevel = metad->btm_fastlevel;
 
-				nextrdata->buffer = InvalidBuffer;
 				nextrdata->data = (char *) &xlmeta;
 				nextrdata->len = sizeof(xl_btree_metadata);
+				nextrdata->buffer = InvalidBuffer;
 				nextrdata->next = nextrdata + 1;
 				nextrdata++;
 				xlinfo = XLOG_BTREE_INSERT_META;
@@ -603,6 +603,7 @@ _bt_insertonpg(Relation rel,
 					(sizeof(BTItemData) - sizeof(IndexTupleData));
 			}
 			nextrdata->buffer = buf;
+			nextrdata->buffer_std = true;
 			nextrdata->next = NULL;
 
 			recptr = XLogInsert(RM_BTREE_ID, xlinfo, rdata);
@@ -853,28 +854,29 @@ _bt_split(Relation rel, Buffer buf, OffsetNumber firstright,
 		xlrec.leftlen = ((PageHeader) leftpage)->pd_special -
 			((PageHeader) leftpage)->pd_upper;
 
-		rdata[0].buffer = InvalidBuffer;
 		rdata[0].data = (char *) &xlrec;
 		rdata[0].len = SizeOfBtreeSplit;
+		rdata[0].buffer = InvalidBuffer;
 		rdata[0].next = &(rdata[1]);
 
-		rdata[1].buffer = InvalidBuffer;
 		rdata[1].data = (char *) leftpage + ((PageHeader) leftpage)->pd_upper;
 		rdata[1].len = xlrec.leftlen;
+		rdata[1].buffer = InvalidBuffer;
 		rdata[1].next = &(rdata[2]);
 
-		rdata[2].buffer = InvalidBuffer;
 		rdata[2].data = (char *) rightpage + ((PageHeader) rightpage)->pd_upper;
 		rdata[2].len = ((PageHeader) rightpage)->pd_special -
 			((PageHeader) rightpage)->pd_upper;
+		rdata[2].buffer = InvalidBuffer;
 		rdata[2].next = NULL;
 
 		if (!P_RIGHTMOST(ropaque))
 		{
 			rdata[2].next = &(rdata[3]);
-			rdata[3].buffer = sbuf;
 			rdata[3].data = NULL;
 			rdata[3].len = 0;
+			rdata[3].buffer = sbuf;
+			rdata[3].buffer_std = true;
 			rdata[3].next = NULL;
 		}
 
@@ -1464,19 +1466,19 @@ _bt_newroot(Relation rel, Buffer lbuf, Buffer rbuf)
 		xlrec.rootblk = rootblknum;
 		xlrec.level = metad->btm_level;
 
-		rdata[0].buffer = InvalidBuffer;
 		rdata[0].data = (char *) &xlrec;
 		rdata[0].len = SizeOfBtreeNewroot;
+		rdata[0].buffer = InvalidBuffer;
 		rdata[0].next = &(rdata[1]);
 
 		/*
 		 * Direct access to page is not good but faster - we should
 		 * implement some new func in page API.
 		 */
-		rdata[1].buffer = InvalidBuffer;
 		rdata[1].data = (char *) rootpage + ((PageHeader) rootpage)->pd_upper;
 		rdata[1].len = ((PageHeader) rootpage)->pd_special -
 			((PageHeader) rootpage)->pd_upper;
+		rdata[1].buffer = InvalidBuffer;
 		rdata[1].next = NULL;
 
 		recptr = XLogInsert(RM_BTREE_ID, XLOG_BTREE_NEWROOT, rdata);