Hi >Specifically, why is the Elapsed at 2.62 minutes and DB Time at 74.32 >minutes. Notice that I didn't read the paper you referenced and I'm replying to this specific point only. Since waits are part of it, DB Time can be much larger that the elapsed time. And since a system is theoretically able to wait for an infinite time for a given time, DB Time can be much bigger than elapsed time. Here a simple example generated on my laptop: SQL> select systimestamp, value from v$sys_time_model where stat_name = 'DB time'; SYSTIMESTAMP VALUE ---------------------------------------- ---------- 11-APR-06 12.02.01.578054 AM +02:00 919620484 SQL> select systimestamp, value from v$sys_time_model where stat_name = 'DB time'; SYSTIMESTAMP VALUE ---------------------------------------- ---------- 11-APR-06 12.02.29.655284 AM +02:00 1095367910 As you can see while between the two queries the elapsed time is about 28 seconds, the DB Time is about 176 seconds. Notice that between the two queries I started a parallel operation with 10 slaves to produce some load... HTH Chris -- //www.freelists.org/webpage/oracle-l