Fix condition for whether end_heap_rewrite must fsync, per Heikki.

diff --git a/src/backend/access/heap/rewriteheap.c b/src/backend/access/heap/rewriteheap.c
index 0783f7353dc67f1bce418eeebb283b5a6226ecf8..96d6d6f2c02d011303d7340a3bf36955c3d49013 100644 (file)
--- 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 1.2 2007/04/17 20:49:39 tgl Exp $
+ *   $PostgreSQL: pgsql/src/backend/access/heap/rewriteheap.c,v 1.3 2007/04/17 21:29:31 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -272,10 +272,17 @@ end_heap_rewrite(RewriteState state)
    }
 
    /*
-    * If not WAL-logging, must fsync before commit.  We use heap_sync
+    * If the rel isn't temp, must fsync before commit.  We use heap_sync
     * to ensure that the toast table gets fsync'd too.
+    *
+    * It's obvious that we must do this when not WAL-logging. It's less
+    * obvious that we have to do it even if we did WAL-log the pages.
+    * The reason is the same as in tablecmds.c's copy_relation_data():
+    * we're writing data that's not in shared buffers, and so a CHECKPOINT
+    * occurring during the rewriteheap operation won't have fsync'd data
+    * we wrote before the checkpoint.
     */
-   if (!state->rs_use_wal)
+   if (!state->rs_new_rel->rd_istemp)
        heap_sync(state->rs_new_rel);
 
    /* Deleting the context frees everything */
@@ -584,7 +591,7 @@ raw_heap_insert(RewriteState state, HeapTuple tup)
            /*
             * Now write the page. We say isTemp = true even if it's not a
             * temp table, because there's no need for smgr to schedule an
-            * fsync for this write; we'll do it ourselves before committing.
+            * fsync for this write; we'll do it ourselves in end_heap_rewrite.
             */
            RelationOpenSmgr(state->rs_new_rel);
            smgrextend(state->rs_new_rel->rd_smgr, state->rs_blockno,