Invent an assign-hook mechanism for psql variables similar to the one

existing for backend GUC variables, and use this to eliminate repeated
fetching/parsing of psql variables in psql's inner loops.  In a trivial
test with lots of 'select 1;' commands, psql's CPU time went down almost
10%, although of course the effect on total elapsed time was much less.
Per discussion about how to ensure the upcoming FETCH_COUNT patch doesn't
cost any performance when not being used.

1 files changed, 3 insertions, 5 deletions

diff --git a/src/bin/psql/large_obj.c b/src/bin/psql/large_obj.c
index 778606c5f0e..48d8931e9fc 100644
--- a/src/bin/psql/large_obj.c
+++ b/src/bin/psql/large_obj.c
@@ -3,7 +3,7 @@
  *
  * Copyright (c) 2000-2006, PostgreSQL Global Development Group
  *
- * $PostgreSQL: pgsql/src/bin/psql/large_obj.c,v 1.45 2006/07/14 14:52:26 momjian Exp $
+ * $PostgreSQL: pgsql/src/bin/psql/large_obj.c,v 1.46 2006/08/29 15:19:51 tgl Exp $
  */
 #include "postgres_fe.h"
 #include "large_obj.h"
@@ -67,8 +67,7 @@ finish_lo_xact(const char *operation, bool own_transaction)
 {
 	PGresult   *res;
 
-	if (own_transaction &&
-		GetVariableBool(pset.vars, "AUTOCOMMIT"))
+	if (own_transaction && pset.autocommit)
 	{
 		/* close out our own xact */
 		if (!(res = PSQLexec("COMMIT", false)))
@@ -91,8 +90,7 @@ fail_lo_xact(const char *operation, bool own_transaction)
 {
 	PGresult   *res;
 
-	if (own_transaction &&
-		GetVariableBool(pset.vars, "AUTOCOMMIT"))
+	if (own_transaction && pset.autocommit)
 	{
 		/* close out our own xact */
 		res = PSQLexec("ROLLBACK", false);