Improve cache invalidation handling. Eespecially
this would fix TODO
* elog() flushes cache, try invalidating just entries from
  current xact, perhaps using invalidation cache

Author: Hiroshi Inoue

src/backend/access/heap/heapam.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.62 1999/12/21 00:06:40 wieck Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.63 2000/01/10 06:30:50 inoue Exp $
  *
  *
  * INTERFACE ROUTINES
@@ -1262,7 +1262,7 @@ heap_insert(Relation relation, HeapTuple tup)
 	RelationPutHeapTupleAtEnd(relation, tup);
 
 	if (IsSystemRelationName(RelationGetRelationName(relation)))
-		RelationInvalidateHeapTuple(relation, tup);
+		RelationMark4RollbackHeapTuple(relation, tup);
 
 	return tup->t_data->t_oid;
 }
@@ -1473,6 +1473,8 @@ heap_update(Relation relation, ItemPointer otid, HeapTuple newtup,
 		RelationPutHeapTupleAtEnd(relation, newtup);
 		LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE);
 	}
+	/* mark for rollback caches */
+	RelationMark4RollbackHeapTuple(relation, newtup);
 
 	/*
 	 * New item in place, now record address of new tuple in t_ctid of old

src/backend/access/transam/xact.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/access/transam/xact.c,v 1.57 2000/01/05 18:23:44 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/access/transam/xact.c,v 1.58 2000/01/10 06:30:50 inoue Exp $
  *
  * NOTES
  *		Transaction aborts can now occur two ways:
@@ -165,6 +165,7 @@ static void AtAbort_Cache(void);
 static void AtAbort_Locks(void);
 static void AtAbort_Memory(void);
 static void AtCommit_Cache(void);
+static void AtCommit_LocalCache(void);
 static void AtCommit_Locks(void);
 static void AtCommit_Memory(void);
 static void AtStart_Cache(void);
@@ -512,8 +513,11 @@ CommandCounterIncrement()
 
 	CurrentTransactionStateData.scanCommandId = CurrentTransactionStateData.commandId;
 
-	/* make cache changes visible to me */
-	AtCommit_Cache();
+	/*
+	 * make cache changes visible to me.  AtCommit_LocalCache()
+	 * instead of AtCommit_Cache() is called here.
+	 */
+	AtCommit_LocalCache();
 	AtStart_Cache();
 
 }
@@ -663,15 +667,26 @@ static void
 AtCommit_Cache()
 {
 	/* ----------------
-	 * Make catalog changes visible to me for the next command.
-	 * Other backends will not process my invalidation messages until
-	 * after I commit and free my locks--though they will do
-	 * unnecessary work if I abort.
+	 * Make catalog changes visible to all backend.
 	 * ----------------
 	 */
 	RegisterInvalid(true);
 }
 
+/* --------------------------------
+ *		AtCommit_LocalCache
+ * --------------------------------
+ */
+static void
+AtCommit_LocalCache()
+{
+	/* ----------------
+	 * Make catalog changes visible to me for the next command.
+	 * ----------------
+	 */
+	ImmediateLocalInvalidation(true);
+}
+
 /* --------------------------------
  *		AtCommit_Locks
  * --------------------------------

src/backend/storage/smgr/md.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/storage/smgr/md.c,v 1.60 1999/11/16 04:13:56 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/storage/smgr/md.c,v 1.61 2000/01/10 06:30:51 inoue Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -20,6 +20,7 @@
 #include "catalog/catalog.h"
 #include "miscadmin.h"
 #include "storage/smgr.h"
+#include "utils/inval.h"	/* ImmediateSharedRelationCacheInvalidate() */
 
 #undef DIAGNOSTIC
 
@@ -203,6 +204,15 @@ mdunlink(Relation reln)
 	 */
 	if (reln->rd_unlinked && reln->rd_fd < 0)
 		return SM_SUCCESS;
+	/*
+	 * This call isn't good for independency of md stuff,but 
+	 * mdunlink() unlinks the base file immediately and couldn't
+	 * be rollbacked in case of abort. We must guarantee all
+	 * backends' relation cache invalidation here.
+	 * This would be unnecessary if unlinking is postponed
+	 * till end of transaction.
+	 */
+	ImmediateSharedRelationCacheInvalidate(reln);
 	/*
 	 * Force all segments of the relation to be opened, so that we
 	 * won't miss deleting any of them.
@@ -779,6 +789,7 @@ mdtruncate(Relation reln, int nblocks)
 #ifndef LET_OS_MANAGE_FILESIZE
 	MemoryContext oldcxt;
 	int			priorblocks;
+	bool	invalregistered = false;
 #endif
 
 	/* NOTE: mdnblocks makes sure we have opened all existing segments,
@@ -810,6 +821,20 @@ mdtruncate(Relation reln, int nblocks)
 			 * a big file...
 			 */
 			FileTruncate(v->mdfd_vfd, 0);
+			/*
+	 		 * To call ImmediateSharedRelationCacheInvalidate() here
+			 * isn't good for independency of md stuff,but smgrunlink()
+			 * removes the base file immediately and couldn't be
+			 * rollbacked in case of abort. We must guarantee
+	 		 * all backends' relation cache invalidation here.
+	 		 * This would be unnecessary if the truncation is postponed
+	 		 * till end of transaction.
+	 		 */
+			if (!invalregistered)
+			{
+				ImmediateSharedRelationCacheInvalidate(reln);
+				invalregistered = true;
+			}
 			FileUnlink(v->mdfd_vfd);
 			v = v->mdfd_chain;
 			Assert(ov != &Md_fdvec[fd]); /* we never drop the 1st segment */