BN, Keep in mind that STATSPACK has a deficiency in the way Top SQL is collected. The package scans V$SQL using a query that has a fixed number of Buffer gets, Disk-reads, etc. that is previously configured. If you have pinned packages/cursors and have not restarted the Db in a while, you will collect SQL that is executed a large number of times for functional 9and valid reasons) that are really NOT the issue. (I deal with this topic in detail in my papers and in my book) > 2. Pick the top few sqls and their hash value from statspack based on "Gets > per Exec" ( you can also compare statspack for a previous day/similar time > when the system was healthy ) As for your disk issue, I wouldn't really depend on 'sar -d'. On modern systems, there are just too many layers inbetween Oracle and the final disk (see previous post). If you want to, I would rather look at the Tablespace/File level I/O as recorded in STATSPACK and look for oddities therein. Finally, of course, you will need to look at Business critical SQL and trace them with 10046 to really determine the issue. -- John Kanagaraj <>< DB Soft Inc http://www.linkedin.com/in/johnkanagaraj http://jkanagaraj.wordpress.com (Sorry - not an Oracle blog!) ** The opinions and facts contained in this message are entirely mine and do not reflect those of my employer or customers ** -- //www.freelists.org/webpage/oracle-l