Restructure local-buffer handling per recent pghackers discussion.

The local buffer manager is no longer used for newly-created relations
(unless they are TEMP); a new non-TEMP relation goes through the shared
bufmgr and thus will participate normally in checkpoints.  But TEMP relations
use the local buffer manager throughout their lifespan.  Also, operations
in TEMP relations are not logged in WAL, thus improving performance.
Since it's no longer necessary to fsync relations as they move out of the
local buffers into shared buffers, quite a lot of smgr.c/md.c/fd.c code
is no longer needed and has been removed: there's no concept of a dirty
relation anymore in md.c/fd.c, and we never fsync anything but WAL.
Still TODO: improve local buffer management algorithms so that it would
be reasonable to increase NLocBuffer.

3 files changed, 41 insertions, 9 deletions

diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index 1abb938fdf8..e9f69476283 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 1.143 2002/07/30 16:08:33 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.144 2002/08/06 02:36:33 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -1155,6 +1155,7 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid)
 	pgstat_count_heap_insert(&relation->pgstat_info);
 
 	/* XLOG stuff */
+	if (!relation->rd_istemp)
 	{
 		xl_heap_insert xlrec;
 		xl_heap_header xlhdr;
@@ -1204,6 +1205,12 @@ heap_insert(Relation relation, HeapTuple tup, CommandId cid)
 		PageSetLSN(page, recptr);
 		PageSetSUI(page, ThisStartUpID);
 	}
+	else
+	{
+		/* No XLOG record, but still need to flag that XID exists on disk */
+		MyXactMadeTempRelUpdate = true;
+	}
+
 	END_CRIT_SECTION();
 
 	LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
@@ -1323,12 +1330,15 @@ l1:
 	}
 
 	START_CRIT_SECTION();
+
 	/* store transaction information of xact deleting the tuple */
 	tp.t_data->t_infomask &= ~(HEAP_XMAX_COMMITTED |
 							 HEAP_XMAX_INVALID | HEAP_MARKED_FOR_UPDATE);
 	HeapTupleHeaderSetXmax(tp.t_data, GetCurrentTransactionId());
 	HeapTupleHeaderSetCmax(tp.t_data, cid);
+
 	/* XLOG stuff */
+	if (!relation->rd_istemp)
 	{
 		xl_heap_delete xlrec;
 		XLogRecPtr	recptr;
@@ -1351,12 +1361,17 @@ l1:
 		PageSetLSN(dp, recptr);
 		PageSetSUI(dp, ThisStartUpID);
 	}
+	else
+	{
+		/* No XLOG record, but still need to flag that XID exists on disk */
+		MyXactMadeTempRelUpdate = true;
+	}
+
 	END_CRIT_SECTION();
 
 	LockBuffer(buffer, BUFFER_LOCK_UNLOCK);
 
 #ifdef TUPLE_TOASTER_ACTIVE
-
 	/*
 	 * If the relation has toastable attributes, we need to delete no
 	 * longer needed items there too.  We have to do this before
@@ -1659,6 +1674,7 @@ l2:
 	oldtup.t_data->t_ctid = newtup->t_self;
 
 	/* XLOG stuff */
+	if (!relation->rd_istemp)
 	{
 		XLogRecPtr	recptr = log_heap_update(relation, buffer, oldtup.t_self,
 											 newbuf, newtup, false);
@@ -1671,6 +1687,11 @@ l2:
 		PageSetLSN(BufferGetPage(buffer), recptr);
 		PageSetSUI(BufferGetPage(buffer), ThisStartUpID);
 	}
+	else
+	{
+		/* No XLOG record, but still need to flag that XID exists on disk */
+		MyXactMadeTempRelUpdate = true;
+	}
 
 	END_CRIT_SECTION();
 
@@ -1927,6 +1948,9 @@ log_heap_clean(Relation reln, Buffer buffer, char *unused, int unlen)
 	XLogRecPtr	recptr;
 	XLogRecData rdata[3];
 
+	/* Caller should not call me on a temp relation */
+	Assert(!reln->rd_istemp);
+
 	xlrec.node = reln->rd_node;
 	xlrec.block = BufferGetBlockNumber(buffer);
 	rdata[0].buffer = InvalidBuffer;
@@ -1978,6 +2002,9 @@ log_heap_update(Relation reln, Buffer oldbuf, ItemPointerData from,
 	Page		page = BufferGetPage(newbuf);
 	uint8		info = (move) ? XLOG_HEAP_MOVE : XLOG_HEAP_UPDATE;
 
+	/* Caller should not call me on a temp relation */
+	Assert(!reln->rd_istemp);
+
 	xlrec.target.node = reln->rd_node;
 	xlrec.target.tid = from;
 	xlrec.newtid = newtup->t_self;
@@ -2012,7 +2039,8 @@ log_heap_update(Relation reln, Buffer oldbuf, ItemPointerData from,
 			xid[0] = HeapTupleHeaderGetXmax(newtup->t_data);
 		xid[1] = HeapTupleHeaderGetXmin(newtup->t_data);
 		memcpy((char *) &xlhdr + hsize,
-		       (char *) xid,            2 * sizeof(TransactionId));
+		       (char *) xid,
+			   2 * sizeof(TransactionId));
 		hsize += 2 * sizeof(TransactionId);
 	}
 	rdata[2].buffer = newbuf;
diff --git a/src/backend/access/heap/hio.c b/src/backend/access/heap/hio.c
index 602ad748d9b..67eb4ad7e24 100644
--- a/src/backend/access/heap/hio.c
+++ b/src/backend/access/heap/hio.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Id: hio.c,v 1.45 2002/06/20 20:29:25 momjian Exp $
+ *	  $Id: hio.c,v 1.46 2002/08/06 02:36:33 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -102,6 +102,7 @@ RelationGetBufferForTuple(Relation relation, Size len,
 	Size		pageFreeSpace;
 	BlockNumber targetBlock,
 				otherBlock;
+	bool		needLock;
 
 	len = MAXALIGN(len);		/* be conservative */
 
@@ -231,9 +232,12 @@ RelationGetBufferForTuple(Relation relation, Size len,
 	 *
 	 * We have to use a lock to ensure no one else is extending the rel at
 	 * the same time, else we will both try to initialize the same new
-	 * page.
+	 * page.  We can skip locking for new or temp relations, however,
+	 * since no one else could be accessing them.
 	 */
-	if (!relation->rd_myxactonly)
+	needLock = !(relation->rd_isnew || relation->rd_istemp);
+
+	if (needLock)
 		LockPage(relation, 0, ExclusiveLock);
 
 	/*
@@ -249,7 +253,7 @@ RelationGetBufferForTuple(Relation relation, Size len,
 	 * Release the file-extension lock; it's now OK for someone else to
 	 * extend the relation some more.
 	 */
-	if (!relation->rd_myxactonly)
+	if (needLock)
 		UnlockPage(relation, 0, ExclusiveLock);
 
 	/*
diff --git a/src/backend/access/heap/tuptoaster.c b/src/backend/access/heap/tuptoaster.c
index 2945cf3458c..1c09af2b308 100644
--- a/src/backend/access/heap/tuptoaster.c
+++ b/src/backend/access/heap/tuptoaster.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/heap/tuptoaster.c,v 1.33 2002/07/20 05:16:56 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/heap/tuptoaster.c,v 1.34 2002/08/06 02:36:33 tgl Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -915,7 +915,7 @@ toast_save_datum(Relation rel, Datum value)
 		 */
 		idxres = index_insert(toastidx, t_values, t_nulls,
 							  &(toasttup->t_self),
-							  toastrel, toastidx->rd_uniqueindex);
+							  toastrel, toastidx->rd_index->indisunique);
 		if (idxres == NULL)
 			elog(ERROR, "Failed to insert index entry for TOAST tuple");