Here's a link to a thread on askTom which contains some views on disk usage for Oracle, the thread goes back to 2000 but has more recent posts. But it does have things to say what oracle files should be separated to different disks if you want to go down that route instead of using the SAME methodology. http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:359617936136 Our current production server (that I inherited) has a complex arrangement of disks with oracle files separated out to different disk arrays. And what we've ended up with is half the disks red hot and the other half under used. -- //www.freelists.org/webpage/oracle-l