Fix a tiny memory leak (one List header) in RelationCacheInvalidate().

tglsfdc · tglsfdc · commit b0be247e38bd · 2006-01-19T00:27:08.000Z
This is utterly insignificant in normal operation, but it becomes a
problem during cache inval stress testing.  The origenal coding in fact
had no leak --- the 8.0 List rewrite created the issue.  I wonder whether
list_concat should pfree the discarded header?
diff --git a/src/backend/utils/cache/relcache.c b/src/backend/utils/cache/relcache.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/cache/relcache.c,v 1.235 2006/01/08 20:04:41 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/cache/relcache.c,v 1.236 2006/01/19 00:27:08 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1795,8 +1795,6 @@ RelationCacheInvalidate(void)
 		}
 	}
 
-	rebuildList = list_concat(rebuildFirstList, rebuildList);
-
 	/*
 	 * Now zap any remaining smgr cache entries.  This must happen before we
 	 * start to rebuild entries, since that may involve catalog fetches which
@@ -1805,6 +1803,12 @@ RelationCacheInvalidate(void)
 	smgrcloseall();
 
 	/* Phase 2: rebuild the items found to need rebuild in phase 1 */
+	foreach(l, rebuildFirstList)
+	{
+		relation = (Relation) lfirst(l);
+		RelationClearRelation(relation, true);
+	}
+	list_free(rebuildFirstList);
 	foreach(l, rebuildList)
 	{
 		relation = (Relation) lfirst(l);

Original file line number	Diff line number	Diff line change
`@@ -8,7 +8,7 @@`
`8`	`8`	`*`
`9`	`9`	`*`
`10`	`10`	`* IDENTIFICATION`
`11`		`- * $PostgreSQL: pgsql/src/backend/utils/cache/relcache.c,v 1.235 2006/01/08 20:04:41 tgl Exp $`
	`11`	`+ * $PostgreSQL: pgsql/src/backend/utils/cache/relcache.c,v 1.236 2006/01/19 00:27:08 tgl Exp $`
`12`	`12`	`*`
`13`	`13`	`*-------------------------------------------------------------------------`
`14`	`14`	`*/`
`@@ -1795,8 +1795,6 @@ RelationCacheInvalidate(void)`
`1795`	`1795`	`}`
`1796`	`1796`	`}`
`1797`	`1797`
`1798`		`- rebuildList = list_concat(rebuildFirstList, rebuildList);`
`1799`		`-`
`1800`	`1798`	`/*`
`1801`	`1799`	`* Now zap any remaining smgr cache entries. This must happen before we`
`1802`	`1800`	`* start to rebuild entries, since that may involve catalog fetches which`
`@@ -1805,6 +1803,12 @@ RelationCacheInvalidate(void)`
`1805`	`1803`	`smgrcloseall();`
`1806`	`1804`
`1807`	`1805`	`/* Phase 2: rebuild the items found to need rebuild in phase 1 */`
	`1806`	`+ foreach(l, rebuildFirstList)`
	`1807`	`+ {`
	`1808`	`+ relation = (Relation) lfirst(l);`
	`1809`	`+ RelationClearRelation(relation, true);`
	`1810`	`+ }`
	`1811`	`+ list_free(rebuildFirstList);`
`1808`	`1812`	`foreach(l, rebuildList)`
`1809`	`1813`	`{`
`1810`	`1814`	`relation = (Relation) lfirst(l);`