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, 22 insertions, 14 deletions

diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index fa9f1a20763..433a4b4538c 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.192 2005/06/06 17:01:22 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.193 2005/06/06 20:22:56 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -1107,9 +1107,9 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid)
 
 		xlrec.target.node = relation->rd_node;
 		xlrec.target.tid = tup->t_self;
-		rdata[0].buffer = InvalidBuffer;
 		rdata[0].data = (char *) &xlrec;
 		rdata[0].len = SizeOfHeapInsert;
+		rdata[0].buffer = InvalidBuffer;
 		rdata[0].next = &(rdata[1]);
 
 		xlhdr.t_natts = tup->t_data->t_natts;
@@ -1121,15 +1121,17 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid)
 		 * 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;
+		rdata[1].buffer = buffer;
+		rdata[1].buffer_std = true;
 		rdata[1].next = &(rdata[2]);
 
-		rdata[2].buffer = buffer;
 		/* PG73FORMAT: write bitmap [+ padding] [+ oid] + data */
 		rdata[2].data = (char *) tup->t_data + offsetof(HeapTupleHeaderData, t_bits);
 		rdata[2].len = tup->t_len - offsetof(HeapTupleHeaderData, t_bits);
+		rdata[2].buffer = buffer;
+		rdata[2].buffer_std = true;
 		rdata[2].next = NULL;
 
 		/*
@@ -1378,14 +1380,15 @@ l1:
 
 		xlrec.target.node = relation->rd_node;
 		xlrec.target.tid = tp.t_self;
-		rdata[0].buffer = InvalidBuffer;
 		rdata[0].data = (char *) &xlrec;
 		rdata[0].len = SizeOfHeapDelete;
+		rdata[0].buffer = InvalidBuffer;
 		rdata[0].next = &(rdata[1]);
 
-		rdata[1].buffer = buffer;
 		rdata[1].data = NULL;
 		rdata[1].len = 0;
+		rdata[1].buffer = buffer;
+		rdata[1].buffer_std = true;
 		rdata[1].next = NULL;
 
 		recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_DELETE, rdata);
@@ -2226,14 +2229,15 @@ l3:
 		xlrec.target.node = relation->rd_node;
 		xlrec.target.tid = tuple->t_self;
 		xlrec.shared_lock = (mode == LockTupleShared);
-		rdata[0].buffer = InvalidBuffer;
 		rdata[0].data = (char *) &xlrec;
 		rdata[0].len = SizeOfHeapLock;
+		rdata[0].buffer = InvalidBuffer;
 		rdata[0].next = &(rdata[1]);
 
-		rdata[1].buffer = *buffer;
 		rdata[1].data = NULL;
 		rdata[1].len = 0;
+		rdata[1].buffer = *buffer;
+		rdata[1].buffer_std = true;
 		rdata[1].next = NULL;
 
 		recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_LOCK, rdata);
@@ -2330,9 +2334,9 @@ log_heap_clean(Relation reln, Buffer buffer, OffsetNumber *unused, int uncnt)
 	xlrec.node = reln->rd_node;
 	xlrec.block = BufferGetBlockNumber(buffer);
 
-	rdata[0].buffer = InvalidBuffer;
 	rdata[0].data = (char *) &xlrec;
 	rdata[0].len = SizeOfHeapClean;
+	rdata[0].buffer = InvalidBuffer;
 	rdata[0].next = &(rdata[1]);
 
 	/*
@@ -2340,7 +2344,6 @@ log_heap_clean(Relation reln, Buffer buffer, OffsetNumber *unused, int uncnt)
 	 * that it is.	When XLogInsert stores the whole buffer, the offsets
 	 * array need not be stored too.
 	 */
-	rdata[1].buffer = buffer;
 	if (uncnt > 0)
 	{
 		rdata[1].data = (char *) unused;
@@ -2351,6 +2354,8 @@ log_heap_clean(Relation reln, Buffer buffer, OffsetNumber *unused, int uncnt)
 		rdata[1].data = NULL;
 		rdata[1].len = 0;
 	}
+	rdata[1].buffer = buffer;
+	rdata[1].buffer_std = true;
 	rdata[1].next = NULL;
 
 	recptr = XLogInsert(RM_HEAP_ID, XLOG_HEAP_CLEAN, rdata);
@@ -2388,14 +2393,15 @@ log_heap_update(Relation reln, Buffer oldbuf, ItemPointerData from,
 	xlrec.target.node = reln->rd_node;
 	xlrec.target.tid = from;
 	xlrec.newtid = newtup->t_self;
-	rdata[0].buffer = InvalidBuffer;
 	rdata[0].data = (char *) &xlrec;
 	rdata[0].len = SizeOfHeapUpdate;
+	rdata[0].buffer = InvalidBuffer;
 	rdata[0].next = &(rdata[1]);
 
-	rdata[1].buffer = oldbuf;
 	rdata[1].data = NULL;
 	rdata[1].len = 0;
+	rdata[1].buffer = oldbuf;
+	rdata[1].buffer_std = true;
 	rdata[1].next = &(rdata[2]);
 
 	xlhdr.hdr.t_natts = newtup->t_data->t_natts;
@@ -2420,15 +2426,17 @@ log_heap_update(Relation reln, Buffer oldbuf, ItemPointerData from,
 	 * 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;
+	rdata[2].buffer = newbuf;
+	rdata[2].buffer_std = true;
 	rdata[2].next = &(rdata[3]);
 
-	rdata[3].buffer = newbuf;
 	/* PG73FORMAT: write bitmap [+ padding] [+ oid] + data */
 	rdata[3].data = (char *) newtup->t_data + offsetof(HeapTupleHeaderData, t_bits);
 	rdata[3].len = newtup->t_len - offsetof(HeapTupleHeaderData, t_bits);
+	rdata[3].buffer = newbuf;
+	rdata[3].buffer_std = true;
 	rdata[3].next = NULL;
 
 	/* If new tuple is the single and first tuple on page... */