Introduce wal_level GUC to explicitly control if information needed for

archival or hot standby should be WAL-logged, instead of deducing that from
other options like archive_mode. This replaces recovery_connections GUC in
the primary, where it now has no effect, but it's still used in the standby
to enable/disable hot standby.

Remove the WAL-logging of "unlogged operations", like creating an index
without WAL-logging and fsyncing it at the end. Instead, we keep a copy of
the wal_mode setting and the settings that affect how much shared memory a
hot standby server needs to track master transactions (max_connections,
max_prepared_xacts, max_locks_per_xact) in pg_control. Whenever the settings
change, at server restart, write a WAL record noting the new settings and
update pg_control. This allows us to notice the change in those settings in
the standby at the right moment, they used to be included in checkpoint
records, but that meant that a changed value was not reflected in the
standby until the first checkpoint after the change.

Bump PG_CONTROL_VERSION and XLOG_PAGE_MAGIC. Whack XLOG_PAGE_MAGIC back to
the sequence it used to follow, before hot standby and subsequent patches
changed it to 0x9003.

1 files changed, 1 insertions, 18 deletions

diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c
index 78df9a8da85..7a1b8e885be 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 1.202 2010/02/26 02:00:37 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/cluster.c,v 1.203 2010/04/28 16:10:41 heikki Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -787,23 +787,6 @@ copy_heap_data(Oid OIDNewHeap, Oid OIDOldHeap, Oid OIDOldIndex,
 	 */
 	use_wal = XLogIsNeeded() && !NewHeap->rd_istemp;
 
-	/*
-	 * Write an XLOG UNLOGGED record if WAL-logging was skipped because WAL
-	 * archiving is not enabled.
-	 */
-	if (!use_wal && !NewHeap->rd_istemp)
-	{
-		char		reason[NAMEDATALEN + 32];
-
-		if (OldIndex != NULL)
-			snprintf(reason, sizeof(reason), "CLUSTER on \"%s\"",
-					 RelationGetRelationName(NewHeap));
-		else
-			snprintf(reason, sizeof(reason), "VACUUM FULL on \"%s\"",
-					 RelationGetRelationName(NewHeap));
-		XLogReportUnloggedStatement(reason);
-	}
-
 	/* use_wal off requires smgr_targblock be initially invalid */
 	Assert(RelationGetTargetBlock(NewHeap) == InvalidBlockNumber);