Thanks, Jared. Yes, running select vs select+rollback in a loop of 1000 iterations I got similar results (average over 3 runs):
STAT...user rollbacks 0 1,000 1,000 LATCH...enqueues 570 1,574 1,004 LATCH...shared pool 7,434 9,063 1,629 STAT...recursive 7,754 10,264 2,510 LATCH...library cache 13,401 17,429 4,028 So, every select w/ a rollback is at least 1 enqueue and 4 latches (1 shared pool + 3 library cache) more expensive than select wo/ a rollback. Since latches are scalability inhibitors - would it be far away from the truth to say that an application that uses OCI session pooling (as opposed to connection pooling I suppose? - just reading chapter 9 of the OCI manual) doesn't scale well with respect to the number of concurrent users? Thanks, Boris Dali. --- Jared Still <[EMAIL PROTECTED]> wrote: > Using a slightly modified version of run_stats to > return > timings in 1/10000 of a second, the timing of 1000 > iterations > of a loop executing noop vs. 1000 doing rollback: > > .0005 secs > .0354 secs > > Here are the stats that were different between the > two, > kind of what you would expect: > > LATCH.cache buffers chains 113 > 133 20 > STAT...redo size 27160 > 27648 488 > STAT...user rollbacks 0 > 1000 1000 > LATCH.enqueues 0 > 1001 1001 > LATCH.shared pool 3 > 1004 1001 > LATCH.session idle bit 0 > 1001 1001 > STAT...execute count 3 > 1004 1001 > LATCH.library cache pin 13 > 2014 2001 > LATCH.session allocation 0 > 2002 2002 > STAT...recursive calls 4 > 2008 2004 > LATCH.library cache 14 > 3018 3004 ______________________________________________________________________ Post your free ad now! http://personals.yahoo.ca -- Please see the official ORACLE-L FAQ: http://www.orafaq.net -- Author: Boris Dali INET: [EMAIL PROTECTED] Fat City Network Services -- 858-538-5051 http://www.fatcity.com San Diego, California -- Mailing list and web hosting services --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
