diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index d7df449a637b8d4a370dfafdee4b4a26d563965b..e5e509f92ca8d6adb4d7d53829603dfdc7f02ba0 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.148 2002/09/04 20:31:09 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.149 2002/09/26 22:46:29 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -1185,10 +1185,14 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid)
 		rdata[0].len = SizeOfHeapInsert;
 		rdata[0].next = &(rdata[1]);
 
-		xlhdr.t_oid = HeapTupleGetOid(tup);
 		xlhdr.t_natts = tup->t_data->t_natts;
+		xlhdr.t_infomask = tup->t_data->t_infomask;
 		xlhdr.t_hoff = tup->t_data->t_hoff;
-		xlhdr.mask = tup->t_data->t_infomask;
+		/*
+		 * note we mark rdata[1] as belonging to buffer; if XLogInsert
+		 * decides to write the whole page to the xlog, we don't need to
+		 * store xl_heap_header in the xlog.
+		 */
 		rdata[1].buffer = buffer;
 		rdata[1].data = (char *) &xlhdr;
 		rdata[1].len = SizeOfHeapHeader;
@@ -1200,7 +1204,11 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid)
 		rdata[2].len = tup->t_len - offsetof(HeapTupleHeaderData, t_bits);
 		rdata[2].next = NULL;
 
-		/* If this is the single and first tuple on page... */
+		/*
+		 * If this is the single and first tuple on page, we can reinit the
+		 * page instead of restoring the whole thing.  Set flag, and hide
+		 * buffer references from XLogInsert.
+		 */
 		if (ItemPointerGetOffsetNumber(&(tup->t_self)) == FirstOffsetNumber &&
 			PageGetMaxOffsetNumber(page) == FirstOffsetNumber)
 		{
@@ -2041,11 +2049,10 @@ log_heap_update(Relation reln, Buffer oldbuf, ItemPointerData from,
 	rdata[1].len = 0;
 	rdata[1].next = &(rdata[2]);
 
-	xlhdr.hdr.t_oid = HeapTupleGetOid(newtup);
 	xlhdr.hdr.t_natts = newtup->t_data->t_natts;
+	xlhdr.hdr.t_infomask = newtup->t_data->t_infomask;
 	xlhdr.hdr.t_hoff = newtup->t_data->t_hoff;
-	xlhdr.hdr.mask = newtup->t_data->t_infomask;
-	if (move)					/* remember xmin & xmax */
+	if (move)					/* remember xmax & xmin */
 	{
 		TransactionId xid[2];	/* xmax, xmin */
 
@@ -2060,6 +2067,10 @@ log_heap_update(Relation reln, Buffer oldbuf, ItemPointerData from,
 			   2 * sizeof(TransactionId));
 		hsize += 2 * sizeof(TransactionId);
 	}
+	/*
+	 * As with insert records, we need not store the rdata[2] segment
+	 * if we decide to store the whole buffer instead.
+	 */
 	rdata[2].buffer = newbuf;
 	rdata[2].data = (char *) &xlhdr;
 	rdata[2].len = hsize;
@@ -2276,18 +2287,16 @@ heap_xlog_insert(bool redo, XLogRecPtr lsn, XLogRecord *record)
 		htup = &tbuf.hdr;
 		MemSet((char *) htup, 0, sizeof(HeapTupleHeaderData));
 		/* PG73FORMAT: get bitmap [+ padding] [+ oid] + data */
-		memcpy((char *) &tbuf + offsetof(HeapTupleHeaderData, t_bits),
+		memcpy((char *) htup + offsetof(HeapTupleHeaderData, t_bits),
 			   (char *) xlrec + SizeOfHeapInsert + SizeOfHeapHeader,
 			   newlen);
 		newlen += offsetof(HeapTupleHeaderData, t_bits);
 		htup->t_natts = xlhdr.t_natts;
+		htup->t_infomask = xlhdr.t_infomask;
 		htup->t_hoff = xlhdr.t_hoff;
-		htup->t_infomask = HEAP_XMAX_INVALID | xlhdr.mask;
 		HeapTupleHeaderSetXmin(htup, record->xl_xid);
 		HeapTupleHeaderSetCmin(htup, FirstCommandId);
 		htup->t_ctid = xlrec->target.tid;
-		if (reln->rd_rel->relhasoids)
-			HeapTupleHeaderSetOid(htup, xlhdr.t_oid);
 
 		offnum = PageAddItem(page, (Item) htup, newlen, offnum,
 							 LP_USED | OverwritePageMode);
@@ -2454,34 +2463,27 @@ newsame:;
 		htup = &tbuf.hdr;
 		MemSet((char *) htup, 0, sizeof(HeapTupleHeaderData));
 		/* PG73FORMAT: get bitmap [+ padding] [+ oid] + data */
-		memcpy((char *) &tbuf + offsetof(HeapTupleHeaderData, t_bits),
+		memcpy((char *) htup + offsetof(HeapTupleHeaderData, t_bits),
 			   (char *) xlrec + hsize,
 			   newlen);
 		newlen += offsetof(HeapTupleHeaderData, t_bits);
 		htup->t_natts = xlhdr.t_natts;
+		htup->t_infomask = xlhdr.t_infomask;
 		htup->t_hoff = xlhdr.t_hoff;
-		if (reln->rd_rel->relhasoids)
-			HeapTupleHeaderSetOid(htup, xlhdr.t_oid);
 
 		if (move)
 		{
 			TransactionId xid[2];		/* xmax, xmin */
 
-			hsize = SizeOfHeapUpdate + SizeOfHeapHeader;
 			memcpy((char *) xid,
-				   (char *) xlrec + hsize, 2 * sizeof(TransactionId));
-			htup->t_infomask = xlhdr.mask;
-			htup->t_infomask &= ~(HEAP_XMIN_COMMITTED |
-								  HEAP_XMIN_INVALID |
-								  HEAP_MOVED_OFF);
-			htup->t_infomask |= HEAP_MOVED_IN;
+				   (char *) xlrec + SizeOfHeapUpdate + SizeOfHeapHeader,
+				   2 * sizeof(TransactionId));
 			HeapTupleHeaderSetXmin(htup, xid[1]);
 			HeapTupleHeaderSetXmax(htup, xid[0]);
 			HeapTupleHeaderSetXvac(htup, record->xl_xid);
 		}
 		else
 		{
-			htup->t_infomask = HEAP_XMAX_INVALID | xlhdr.mask;
 			HeapTupleHeaderSetXmin(htup, record->xl_xid);
 			HeapTupleHeaderSetCmin(htup, FirstCommandId);
 		}
diff --git a/src/include/access/htup.h b/src/include/access/htup.h
index 6da127e4d4b028de2d3d8eadf8f66e756d88d348..f340c8143ac73e7944cd6f8123216d11fa782515 100644
--- a/src/include/access/htup.h
+++ b/src/include/access/htup.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: htup.h,v 1.60 2002/09/04 20:31:37 momjian Exp $
+ * $Id: htup.h,v 1.61 2002/09/26 22:46:29 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -261,6 +261,8 @@ do { \
 
 
 /*
+ * WAL record definitions for heapam.c's WAL operations
+ *
  * XLOG allows to store some information in high 4 bits of log
  * record xl_info field
  */
@@ -300,15 +302,22 @@ typedef struct xl_heap_delete
 
 #define SizeOfHeapDelete	(offsetof(xl_heap_delete, target) + SizeOfHeapTid)
 
+/*
+ * We don't store the whole fixed part (HeapTupleHeaderData) of an inserted
+ * or updated tuple in WAL; we can save a few bytes by reconstructing the
+ * fields that are available elsewhere in the WAL record, or perhaps just
+ * plain needn't be reconstructed.  These are the fields we must store.
+ * NOTE: t_hoff could be recomputed, but we may as well store it because
+ * it will come for free due to alignment considerations.
+ */
 typedef struct xl_heap_header
 {
-	Oid			t_oid;
 	int16		t_natts;
+	uint16		t_infomask;
 	uint8		t_hoff;
-	uint8		mask;			/* low 8 bits of t_infomask */
 } xl_heap_header;
 
-#define SizeOfHeapHeader	(offsetof(xl_heap_header, mask) + sizeof(uint8))
+#define SizeOfHeapHeader	(offsetof(xl_heap_header, t_hoff) + sizeof(uint8))
 
 /* This is what we need to know about insert */
 typedef struct xl_heap_insert
@@ -340,6 +349,8 @@ typedef struct xl_heap_clean
 
 #define SizeOfHeapClean (offsetof(xl_heap_clean, block) + sizeof(BlockNumber))
 
+
+
 /*
  * MaxTupleSize is the maximum allowed size of a tuple, including header and
  * MAXALIGN alignment padding.	Basically it's BLCKSZ minus the other stuff
diff --git a/src/include/access/xlog.h b/src/include/access/xlog.h
index bf2ce611f7f4fd18f2a9ceeadc44431acad3645f..c8c49936803e1fc1318fc1991a587703d333ed22 100644
--- a/src/include/access/xlog.h
+++ b/src/include/access/xlog.h
@@ -6,7 +6,7 @@
  * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: xlog.h,v 1.37 2002/09/04 20:31:37 momjian Exp $
+ * $Id: xlog.h,v 1.38 2002/09/26 22:46:29 tgl Exp $
  */
 #ifndef XLOG_H
 #define XLOG_H
@@ -110,7 +110,7 @@ typedef struct XLogContRecord
 /*
  * Each page of XLOG file has a header like this:
  */
-#define XLOG_PAGE_MAGIC 0xD059	/* can be used as WAL version indicator */
+#define XLOG_PAGE_MAGIC 0xD05A	/* can be used as WAL version indicator */
 
 typedef struct XLogPageHeaderData
 {