You can use my script that is mentioned here http://karlarao.wordpress.com/2010/01/31/workload-characterization-using-dba_hist-tables-and-ksar/ , that's on the instance level so if you are running RAC you should also run it on the other nodes. If you want to have just the certain period you can edit the script to filter on particular workload periods .. example.. every Mon-Fri, 9am-6pm Take note that this uses AWR, but you can also do the same on Statspack. Also to be statistical about the data points you could check my example here http://karlarao.tiddlyspot.com/#dbms_stat_funcs which you could make use of the Oracle statistical functions <http://karlarao.wordpress.com/2010/01/31/workload-characterization-using-dba_hist-tables-and-ksar/> -- Karl Arao karlarao.wordpress.com karlarao.tiddlyspot.com