A 10053 trace won't do you any good if the plans are the same. But you don't necessarily need a 10046 trace either. Just looking at v$session_event will give you that info as well. I've taken a page out of Tom Kyte's runstats script and created bstat / estat sql scripts. bstat save the current values to a GTT. Estat does the same and the prints the deltas. Or you could use Tanel's snapper script. Although that could present a problem for the faster query. Regards Wolfgang Breitling Centrex Consulting Corporation http://www.centrexcc.com On 2012-01-16, at 3:04 PM, Taylor, Chris David wrote: > > D1: > Elapsed times include waiting on following events: > Event waited on Times Max. Wait Total Waited > ---------------------------------------- Waited ---------- ------------ > SQL*Net message to client 1 0.00 0.00 > direct path write temp 1016 0.09 0.44 > latch free 1 0.00 0.00 > direct path read temp 4572 0.03 3.79 > <------------------ LOOK > db file sequential read 238 0.01 0.55 > db file scattered read 229 0.01 0.50 > SQL*Net message from client 1 4.74 4.74 > ******************************************************************************* > > D2: > Elapsed times include waiting on following events: > Event waited on Times Max. Wait Total Waited > ---------------------------------------- Waited ---------- ------------ > SQL*Net message to client 1 0.00 0.00 > direct path write temp 1030 0.08 0.18 > db file sequential read 2 0.00 0.00 > local write wait 171 0.01 0.25 > direct path read temp 66950 0.19 39.85 > <-----------------------LOOK > SQL*Net message from client 1 32.32 32.32 > ******************************************************************************* > > I'm such a dumb*** sometimes. > > I was out of (or low in) PGA memory in D2 due to the heavy usage by the > development staff. > > Bump up PGA_AGGREGATE_TARGET and performance goes back to sub 3 secs for the > query. Now D1 and D2 perform exact. > > This is WHY a 10046 trace should be FIRST step in examining a performance > issue so you can *know* what you are waiting on before even thinking about > 10053 traces. (In my honest opinion anyway). > -- //www.freelists.org/webpage/oracle-l