Avoid having autovacuum run multiple ANALYZE commands in a single transaction,

to prevent possible deadlock problems.  Per request from Tom Lane.

diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index abb0eda4f7f948a8ffe4aa9a639edee47802b4b5..80c1e31121bc2b5a73ef9b98c68326481db4c6b1 100644 (file)
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -13,7 +13,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/backend/commands/vacuum.c,v 1.317.2.4 2007/03/14 18:49:12 tgl Exp $
+ *       $PostgreSQL: pgsql/src/backend/commands/vacuum.c,v 1.317.2.5 2007/06/14 13:54:40 alvherre Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -389,14 +389,17 @@ vacuum(VacuumStmt *vacstmt, List *relids)
         * For ANALYZE (no VACUUM): if inside a transaction block, we cannot
         * start/commit our own transactions.  Also, there's no need to do so if
         * only processing one relation.  For multiple relations when not within a
-        * transaction block, use own transactions so we can release locks sooner.
+        * transaction block, and also in an autovacuum worker, use own
+        * transactions so we can release locks sooner.
         */
        if (vacstmt->vacuum)
                use_own_xacts = true;
        else
        {
                Assert(vacstmt->analyze);
-               if (in_outer_xact)
+               if (IsAutoVacuumProcess())
+                       use_own_xacts = true;
+               else if (in_outer_xact)
                        use_own_xacts = false;
                else if (list_length(relations) > 1)
                        use_own_xacts = true;