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, 11 deletions

diff --git a/src/backend/access/heap/rewriteheap.c b/src/backend/access/heap/rewriteheap.c
index 5c60c1f130d..e35fbeb9b1a 100644
--- a/src/backend/access/heap/rewriteheap.c
+++ b/src/backend/access/heap/rewriteheap.c
@@ -96,7 +96,7 @@
  * Portions Copyright (c) 1994-5, Regents of the University of California
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/access/heap/rewriteheap.c,v 1.21 2010/02/26 02:00:33 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/access/heap/rewriteheap.c,v 1.22 2010/04/28 16:10:40 heikki Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -278,16 +278,6 @@ end_heap_rewrite(RewriteState state)
 				   (char *) state->rs_buffer, true);
 	}
 
-	/* Write an XLOG UNLOGGED record if WAL-logging was skipped */
-	if (!state->rs_use_wal && !state->rs_new_rel->rd_istemp)
-	{
-		char		reason[NAMEDATALEN + 30];
-
-		snprintf(reason, sizeof(reason), "heap rewrite on \"%s\"",
-				 RelationGetRelationName(state->rs_new_rel));
-		XLogReportUnloggedStatement(reason);
-	}
-
 	/*
 	 * If the rel isn't temp, must fsync before commit.  We use heap_sync to
 	 * ensure that the toast table gets fsync'd too.