Fix small query-lifespan memory leak in bulk updates.

tglsfdc · tglsfdc · commit ae4760d667c7 · 2016-08-24T22:20:25.000-04:00
When there is an identifiable REPLICA IDENTITY index on the target table, heap_update leaks the id_attrs bitmapset. That's not many bytes, but it adds up over enough rows, since the code typically runs in a query-lifespan context. Bug introduced in commit e55704d, which did a rather poor job of cloning the existing use-pattern for RelationGetIndexAttrBitmap(). Per bug #14293 from Zhou Digoal. Back-patch to 9.4 where the bug was introduced. Report: <20160824114320.15676.45171@wrigleys.postgresql.org>
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
@@ -3802,6 +3802,7 @@ heap_update(Relation relation, ItemPointer otid, HeapTuple newtup,
 			ReleaseBuffer(vmbuffer);
 		bms_free(hot_attrs);
 		bms_free(key_attrs);
+		bms_free(id_attrs);
 		return result;
 	}
 
@@ -4268,6 +4269,7 @@ heap_update(Relation relation, ItemPointer otid, HeapTuple newtup,
 
 	bms_free(hot_attrs);
 	bms_free(key_attrs);
+	bms_free(id_attrs);
 
 	return HeapTupleMayBeUpdated;
 }

Original file line number	Diff line number	Diff line change
`@@ -3802,6 +3802,7 @@ heap_update(Relation relation, ItemPointer otid, HeapTuple newtup,`
`3802`	`3802`	`ReleaseBuffer(vmbuffer);`
`3803`	`3803`	`bms_free(hot_attrs);`
`3804`	`3804`	`bms_free(key_attrs);`
	`3805`	`+ bms_free(id_attrs);`
`3805`	`3806`	`return result;`
`3806`	`3807`	`}`
`3807`	`3808`
`@@ -4268,6 +4269,7 @@ heap_update(Relation relation, ItemPointer otid, HeapTuple newtup,`
`4268`	`4269`
`4269`	`4270`	`bms_free(hot_attrs);`
`4270`	`4271`	`bms_free(key_attrs);`
	`4272`	`+ bms_free(id_attrs);`
`4271`	`4273`
`4272`	`4274`	`return HeapTupleMayBeUpdated;`
`4273`	`4275`	`}`