Back-patch fix to ensure that VACUUM always calls FlushRelationBuffers.

diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 0c0c5f4785d9aff6df0d3ccc3935a55386bf2089..c57cbb9c2fb70b99d374fbc9b42566a181f7651f 100644 (file)
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.148 2000/05/19 03:22:29 tgl Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/commands/vacuum.c,v 1.148.2.1 2000/09/19 21:01:04 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -645,6 +645,19 @@ vc_vacone(Oid relid, bool analyze, List *va_cols)
                if (vacuum_pages.vpl_num_pages > 0)             /* Clean pages from
                                                                                                 * vacuum_pages list */
                        vc_vacheap(vacrelstats, onerel, &vacuum_pages);
+               else
+               {
+                       /*
+                        * Flush dirty pages out to disk.  We must do this even if we
+                        * didn't do anything else, because we want to ensure that all
+                        * tuples have correct on-row commit status on disk (see
+                        * bufmgr.c's comments for FlushRelationBuffers()).
+                        */
+                       i = FlushRelationBuffers(onerel, vacrelstats->num_pages);
+                       if (i < 0)
+                               elog(ERROR, "VACUUM (vc_vacone): FlushRelationBuffers returned %d",
+                                        i);
+               }
        }
        if (reindex)
                activate_indexes_of_a_table(relid, true);
@@ -1968,12 +1981,19 @@ failed to add item with len = %u to page %u (free space %u, nusd %u, noff %u)",
                pfree(Nvpl.vpl_pagedesc);
        }
 
+       /*
+        * Flush dirty pages out to disk.  We do this unconditionally, even if
+        * we don't need to truncate, because we want to ensure that all tuples
+        * have correct on-row commit status on disk (see bufmgr.c's comments
+        * for FlushRelationBuffers()).
+        */
+       i = FlushRelationBuffers(onerel, blkno);
+       if (i < 0)
+               elog(ERROR, "VACUUM (vc_repair_frag): FlushRelationBuffers returned %d", i);
+
        /* truncate relation, after flushing any dirty pages out to disk */
        if (blkno < nblocks)
        {
-               i = FlushRelationBuffers(onerel, blkno);
-               if (i < 0)
-                       elog(FATAL, "VACUUM (vc_repair_frag): FlushRelationBuffers returned %d", i);
                blkno = smgrtruncate(DEFAULT_SMGR, onerel, blkno);
                Assert(blkno >= 0);
                vacrelstats->num_pages = blkno; /* set new number of blocks */
@@ -2023,27 +2043,25 @@ vc_vacheap(VRelStats *vacrelstats, Relation onerel, VPageList vacuum_pages)
                }
        }
 
+       /*
+        * Flush dirty pages out to disk.  We do this unconditionally, even if
+        * we don't need to truncate, because we want to ensure that all tuples
+        * have correct on-row commit status on disk (see bufmgr.c's comments
+        * for FlushRelationBuffers()).
+        */
+       Assert(vacrelstats->num_pages >= vacuum_pages->vpl_empty_end_pages);
+       nblocks = vacrelstats->num_pages - vacuum_pages->vpl_empty_end_pages;
+
+       i = FlushRelationBuffers(onerel, nblocks);
+       if (i < 0)
+               elog(ERROR, "VACUUM (vc_vacheap): FlushRelationBuffers returned %d", i);
+
        /* truncate relation if there are some empty end-pages */
        if (vacuum_pages->vpl_empty_end_pages > 0)
        {
-               Assert(vacrelstats->num_pages >= vacuum_pages->vpl_empty_end_pages);
-               nblocks = vacrelstats->num_pages - vacuum_pages->vpl_empty_end_pages;
                elog(MESSAGE_LEVEL, "Rel %s: Pages: %u --> %u.",
                         RelationGetRelationName(onerel),
                         vacrelstats->num_pages, nblocks);
-
-               /*
-                * We have to flush "empty" end-pages (if changed, but who knows
-                * it) before truncation
-                *
-                * XXX is FlushBufferPool() still needed here?
-                */
-               FlushBufferPool();
-
-               i = FlushRelationBuffers(onerel, nblocks);
-               if (i < 0)
-                       elog(FATAL, "VACUUM (vc_vacheap): FlushRelationBuffers returned %d", i);
-
                nblocks = smgrtruncate(DEFAULT_SMGR, onerel, nblocks);
                Assert(nblocks >= 0);
                vacrelstats->num_pages = nblocks;               /* set new number of