Always call ExecShutdownNode() if appropriate.

Call ExecShutdownNode() after ExecutePlan()'s loop, rather than at each
break.  We had forgotten to do that in one case.  The omission caused
intermittent "temporary file leak" warnings from multi-batch parallel
hash joins with a LIMIT clause.

Back-patch to 11.  Though the problem exists in theory in earlier
parallel query releases, nothing really depended on it.

Author: Kyotaro Horiguchi
Reviewed-by: Thomas Munro, Amit Kapila
Discussion: https://postgr.es/m/20191111.212418.2222262873417235945.horikyota.ntt%40gmail.com

diff --git a/src/backend/executor/execMain.c b/src/backend/executor/execMain.c
index 0abb620050bd0480f7918c37ec4e52546e75d5fe..de9aaf3f766e89210556c55b864a5bda9264303a 100644 (file)
--- a/src/backend/executor/execMain.c
+++ b/src/backend/executor/execMain.c
@@ -1727,15 +1727,7 @@ ExecutePlan(EState *estate,
         * process so we just end the loop...
         */
        if (TupIsNull(slot))
-       {
-           /*
-            * If we know we won't need to back up, we can release resources
-            * at this point.
-            */
-           if (!(estate->es_top_eflags & EXEC_FLAG_BACKWARD))
-               (void) ExecShutdownNode(planstate);
            break;
-       }
 
        /*
         * If we have a junk filter, then project a new tuple with the junk
@@ -1778,17 +1770,16 @@ ExecutePlan(EState *estate,
         */
        current_tuple_count++;
        if (numberTuples && numberTuples == current_tuple_count)
-       {
-           /*
-            * If we know we won't need to back up, we can release resources
-            * at this point.
-            */
-           if (!(estate->es_top_eflags & EXEC_FLAG_BACKWARD))
-               (void) ExecShutdownNode(planstate);
            break;
-       }
    }
 
+   /*
+    * If we know we won't need to back up, we can release resources at this
+    * point.
+    */
+   if (!(estate->es_top_eflags & EXEC_FLAG_BACKWARD))
+       (void) ExecShutdownNode(planstate);
+
    if (use_parallel_mode)
        ExitParallelMode();
 }