diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index f8b8c5b064..176bd00693 100644
--- 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 1.374 2008/05/15 00:17:39 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/vacuum.c,v 1.375 2008/06/05 15:47:32 alvherre Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -210,7 +210,7 @@ static BufferAccessStrategy vac_strategy;
 
 
 /* non-export function prototypes */
-static List *get_rel_oids(List *relids, const RangeVar *vacrel,
+static List *get_rel_oids(Oid relid, const RangeVar *vacrel,
 			 const char *stmttype);
 static void vac_truncate_clog(TransactionId frozenXID);
 static void vacuum_rel(Oid relid, VacuumStmt *vacstmt, char expected_relkind,
@@ -264,9 +264,9 @@ static Size PageGetFreeSpaceWithFillFactor(Relation relation, Page page);
 /*
  * Primary entry point for VACUUM and ANALYZE commands.
  *
- * relids is normally NIL; if it is not, then it provides the list of
- * relation OIDs to be processed, and vacstmt->relation is ignored.
- * (The non-NIL case is currently only used by autovacuum.)
+ * relid is normally InvalidOid; if it is not, then it provides the relation
+ * OID to be processed, and vacstmt->relation is ignored.  (The non-invalid
+ * case is currently only used by autovacuum.)
  *
  * for_wraparound is used by autovacuum to let us know when it's forcing
  * a vacuum for wraparound, which should not be auto-cancelled.
@@ -276,12 +276,12 @@ static Size PageGetFreeSpaceWithFillFactor(Relation relation, Page page);
  *
  * isTopLevel should be passed down from ProcessUtility.
  *
- * It is the caller's responsibility that vacstmt, relids, and bstrategy
+ * It is the caller's responsibility that vacstmt and bstrategy
  * (if given) be allocated in a memory context that won't disappear
  * at transaction commit.
  */
 void
-vacuum(VacuumStmt *vacstmt, List *relids,
+vacuum(VacuumStmt *vacstmt, Oid relid,
 	   BufferAccessStrategy bstrategy, bool for_wraparound, bool isTopLevel)
 {
 	const char *stmttype = vacstmt->vacuum ? "VACUUM" : "ANALYZE";
@@ -351,13 +351,13 @@ vacuum(VacuumStmt *vacstmt, List *relids,
 	vac_strategy = bstrategy;
 
 	/* Remember whether we are processing everything in the DB */
-	all_rels = (relids == NIL && vacstmt->relation == NULL);
+	all_rels = (!OidIsValid(relid) && vacstmt->relation == NULL);
 
 	/*
 	 * Build list of relations to process, unless caller gave us one. (If we
 	 * build one, we put it in vac_context for safekeeping.)
 	 */
-	relations = get_rel_oids(relids, vacstmt->relation, stmttype);
+	relations = get_rel_oids(relid, vacstmt->relation, stmttype);
 
 	/*
 	 * Decide whether we need to start/commit our own transactions.
@@ -531,16 +531,19 @@ vacuum(VacuumStmt *vacstmt, List *relids,
  * per-relation transactions.
  */
 static List *
-get_rel_oids(List *relids, const RangeVar *vacrel, const char *stmttype)
+get_rel_oids(Oid relid, const RangeVar *vacrel, const char *stmttype)
 {
 	List	   *oid_list = NIL;
 	MemoryContext oldcontext;
 
-	/* List supplied by VACUUM's caller? */
-	if (relids)
-		return relids;
-
-	if (vacrel)
+	/* OID supplied by VACUUM's caller? */
+	if (OidIsValid(relid))
+	{
+		oldcontext = MemoryContextSwitchTo(vac_context);
+		oid_list = lappend_oid(oid_list, relid);
+		MemoryContextSwitchTo(oldcontext);
+	}
+	else if (vacrel)
 	{
 		/* Process a specific relation */
 		Oid			relid;
diff --git a/src/backend/postmaster/autovacuum.c b/src/backend/postmaster/autovacuum.c
index 5711093d9e..7ac0bae1c5 100644
--- a/src/backend/postmaster/autovacuum.c
+++ b/src/backend/postmaster/autovacuum.c
@@ -55,7 +55,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/postmaster/autovacuum.c,v 1.78 2008/05/15 00:17:40 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/postmaster/autovacuum.c,v 1.79 2008/06/05 15:47:32 alvherre Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1244,8 +1244,7 @@ do_start_worker(void)
  * left to do_start_worker.
  *
  * This routine is also expected to insert an entry into the database list if
- * the selected database was previously absent from the list.  It returns the
- * new database list.
+ * the selected database was previously absent from the list.
  */
 static void
 launch_worker(TimestampTz now)
@@ -2601,8 +2600,6 @@ autovacuum_do_vac_analyze(Oid relid, bool dovacuum, bool doanalyze,
 						  BufferAccessStrategy bstrategy)
 {
 	VacuumStmt	vacstmt;
-	List	   *relids;
-	MemoryContext old_cxt;
 
 	/* Set up command parameters --- use a local variable instead of palloc */
 	MemSet(&vacstmt, 0, sizeof(vacstmt));
@@ -2613,21 +2610,13 @@ autovacuum_do_vac_analyze(Oid relid, bool dovacuum, bool doanalyze,
 	vacstmt.analyze = doanalyze;
 	vacstmt.freeze_min_age = freeze_min_age;
 	vacstmt.verbose = false;
-	vacstmt.relation = NULL;	/* not used since we pass a relids list */
+	vacstmt.relation = NULL;	/* not used since we pass a relid */
 	vacstmt.va_cols = NIL;
 
-	/*
-	 * The list must survive transaction boundaries, so make sure we create it
-	 * in a long-lived context
-	 */
-	old_cxt = MemoryContextSwitchTo(AutovacMemCxt);
-	relids = list_make1_oid(relid);
-	MemoryContextSwitchTo(old_cxt);
-
 	/* Let pgstat know what we're doing */
 	autovac_report_activity(&vacstmt, relid);
 
-	vacuum(&vacstmt, relids, bstrategy, for_wraparound, true);
+	vacuum(&vacstmt, relid, bstrategy, for_wraparound, true);
 }
 
 /*
diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
index df3887b1dc..1bebfec182 100644
--- a/src/backend/tcop/utility.c
+++ b/src/backend/tcop/utility.c
@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/tcop/utility.c,v 1.291 2008/03/19 18:38:30 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/tcop/utility.c,v 1.292 2008/06/05 15:47:32 alvherre Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1032,7 +1032,8 @@ ProcessUtility(Node *parsetree,
 			break;
 
 		case T_VacuumStmt:
-			vacuum((VacuumStmt *) parsetree, NIL, NULL, false, isTopLevel);
+			vacuum((VacuumStmt *) parsetree, InvalidOid, NULL, false,
+				   isTopLevel);
 			break;
 
 		case T_ExplainStmt:
diff --git a/src/include/commands/vacuum.h b/src/include/commands/vacuum.h
index d5ebec0010..6496fe7868 100644
--- a/src/include/commands/vacuum.h
+++ b/src/include/commands/vacuum.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/commands/vacuum.h,v 1.76 2008/03/14 17:25:59 alvherre Exp $
+ * $PostgreSQL: pgsql/src/include/commands/vacuum.h,v 1.77 2008/06/05 15:47:32 alvherre Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -113,7 +113,7 @@ extern int	vacuum_freeze_min_age;
 
 
 /* in commands/vacuum.c */
-extern void vacuum(VacuumStmt *vacstmt, List *relids,
+extern void vacuum(VacuumStmt *vacstmt, Oid relid,
 	   BufferAccessStrategy bstrategy, bool for_wraparound, bool isTopLevel);
 extern void vac_open_indexes(Relation relation, LOCKMODE lockmode,
 				 int *nindexes, Relation **Irel);