#3 is a good guess... but i ran this on a larger dataset over the weekend when production is not that busy. It ran for 18 hours and I had to kill it. The waits were pretty much all on the straight inserts without any wait events associated with it. I ran it with a smaller data set since I wanted it to complete so I can get the plans. The plans are the same in dev and test. The difference in time is almost all associate with inserts, but I do not have any coresponding wait events. The inserts are a row by row insert that runs in a loop. Outer cursor query query query insert end loop; Yes i know this is not good code. I am not allowed to change the code in the short term. There is a long change process this would have to go through. 2009/8/10 Ric Van Dyke <ric.van.dyke@xxxxxxxxxx> > Generally the unaccounted for time breaks out into these five buckets: > > > > 1 Measurement intrusion effect (> 0, is negligibly small) > > 2 Quantization Error (→ 0, is negligibly small) > > 3 Time spent Not executing (unconstrained) > > 4 Un-instrumented time (→ 0, if your kernel is patched) > > 5 CPU double-counting during OS calls (≤ 0, is negligibly small) > > > > Most likely it’s #3 and it would make some since that you are on the CPU > but not executing as much on Production as you do in Test since I will make > the grand assumption that there are a lot more folks doing things on > production then there are on test. Oracle doesn’t know how long you spend on > the CPU but in the ready to run queue and not actually on the CPU doing > work. The more folks on the system, the more time you will likely spend in > the queue while on the CPU. > > > > If you want to know more about this, get the book “Optimizing Oracle > Performance” and/or come to a Hotsos training class (Oracle Performance > Management > > Using Response Time Profiling) where we cover this in great detail. > > > > ----------------------- > > Ric Van Dyke > > Hotsos Enterprises > > ----------------------- > > > > *Hotsos Symposium * > > *March 7 ?C 11, 2010 * > > *Be there.* > > > > > ------------------------------ > > *From:* oracle-l-bounce@xxxxxxxxxxxxx [mailto: > oracle-l-bounce@xxxxxxxxxxxxx] *On Behalf Of *Dba DBA > *Sent:* Monday, August 10, 2009 4:23 PM > *To:* oracle-l@xxxxxxxxxxxxx > *Subject:* unaccounted for time in a tkprof output > > > > I have this on otn. I didn't want to copy it to email since I can't > properly format the tkprof outputs. > > > > How do I have extra elapsed time with out wait events to account for it? I > am trying to figure out why inserts take longer in production and I don't > have a wait to go on. > > > > http://forums.oracle.com/forums/thread.jspa?messageID=3683942#3683942 > > > > >