"Unaccounted for time" in 10046 is also equal to "Unaccounted for DB time" which is the "CPU Wait" as I investigated here http://goo.gl/5WaAg and you can easily see this on the OEM perf page which is shown as another kind of CPU metric.. also you may want to run this during the execution of your SQL http://www.kylehailey.com/oracle-cpu-time/ and paste the output here I agree with Frits on the perf tool, and Hans on the VM -- Karl Arao Blog: karlarao.wordpress.com Wiki: karlarao.tiddlyspot.com Twitter: @karlarao <http://twitter.com/karlarao> -- //www.freelists.org/webpage/oracle-l