Raj: You are quite correct. KGLSIM is Library Cache SIMulator. It is used for Shared Pool/Library Cache advisor. I am not sure any event or underscores to turn that off. Do you have the errors quite often? I would like to see the errorstack if that is the case. Thanks --=20 Best Regards, K Gopalakrishnan=20 Co-Author: Oracle Wait Interface, Oracle Press 2004 http://www.amazon.com/exec/obidos/tg/detail/-/007222729X/ -- //www.freelists.org/webpage/oracle-l