production booking take more time

 Hi

we are using ebs11i with database 8i.some time user are facing  problem that production booking take more time but booking is not completed status is showing hang.

when we are execute the following query than we found some seesion has waiter and holder.we find the holder sid and kill the session.After kill the session system is working fine.

SELECT DECODE(request,0,'Holder: ',' Waiter: ')||sid sess,id1,id2, lmode,inst_id, request, type
FROM GV$LOCK WHERE (id1, id2, type)
IN
(SELECT id1, id2, type FROM GV$LOCK WHERE request>0) ORDER BY id1, request