Teach CLUSTER to skip writing WAL if not needed (ie, not using archiving)

--- Simon.
Also, code review and cleanup for the previous COPY-no-WAL patches --- Tom.

1 files changed, 18 insertions, 2 deletions

diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c
index aa911369409..ac771b77a60 100644
--- a/src/backend/commands/cluster.c
+++ b/src/backend/commands/cluster.c
@@ -11,7 +11,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/cluster.c,v 1.157 2007/03/13 00:33:39 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/cluster.c,v 1.158 2007/03/29 00:15:37 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -653,6 +653,8 @@ copy_heap_data(Oid OIDNewHeap, Oid OIDOldHeap, Oid OIDOldIndex)
 	char	   *nulls;
 	IndexScanDesc scan;
 	HeapTuple	tuple;
+	CommandId	mycid = GetCurrentCommandId();
+	bool		use_wal;
 
 	/*
 	 * Open the relations we need.
@@ -676,6 +678,17 @@ copy_heap_data(Oid OIDNewHeap, Oid OIDOldHeap, Oid OIDOldIndex)
 	memset(nulls, 'n', natts * sizeof(char));
 
 	/*
+	 * We need to log the copied data in WAL iff WAL archiving is enabled AND
+	 * it's not a temp rel.  (Since we know the target relation is new and
+	 * can't have any FSM data, we can always tell heap_insert to ignore FSM,
+	 * even when using WAL.)
+	 */
+	use_wal = XLogArchivingActive() && !NewHeap->rd_istemp;
+
+	/* use_wal off requires rd_targblock be initially invalid */
+	Assert(NewHeap->rd_targblock == InvalidBlockNumber);
+
+	/*
 	 * Scan through the OldHeap on the OldIndex and copy each tuple into the
 	 * NewHeap.
 	 */
@@ -722,7 +735,7 @@ copy_heap_data(Oid OIDNewHeap, Oid OIDOldHeap, Oid OIDOldIndex)
 		if (NewHeap->rd_rel->relhasoids)
 			HeapTupleSetOid(copiedTuple, HeapTupleGetOid(tuple));
 
-		simple_heap_insert(NewHeap, copiedTuple);
+		heap_insert(NewHeap, copiedTuple, mycid, use_wal, false);
 
 		heap_freetuple(copiedTuple);
 
@@ -734,6 +747,9 @@ copy_heap_data(Oid OIDNewHeap, Oid OIDOldHeap, Oid OIDOldIndex)
 	pfree(values);
 	pfree(nulls);
 
+	if (!use_wal)
+		heap_sync(NewHeap);
+
 	index_close(OldIndex, NoLock);
 	heap_close(OldHeap, NoLock);
 	heap_close(NewHeap, NoLock);