Oracle recommended it, but with the disclaimer that you do your own testing. The test setup is currently in progress. I would like to hear from DBA'S who actually implemented it and how did it impact performance? --------------- Thank You. -----Original Message----- From: Andrew Kerber <andrew.kerber@xxxxxxxxx> Sent: Thursday, June 18, 2009 6:04 PM To: fmhabash@xxxxxxxxx Cc: Oracle-L Group <oracle-l@xxxxxxxxxxxxx> Subject: Re: Monitoring CBO degrading Switches in xplans? Did you try turning off bind variable peeking or histograms? On Thu, Jun 18, 2009 at 4:51 PM, Fmhabash <fmhabash@xxxxxxxxx> wrote: > This is an issue that has made sleepless over and over again. Critical > application sql changes its xplans causing elapse time to go unacceptably > worst. > We eventually wanted to monitor this kind of event proactively. To this > effect, we query top n sql from awr order by elapsed time. We then compare > most recent ET value to the previous n samples. We then calculate cost of > current plan and compare it to existing awr ones cost. > With all this info, we alert if ET and plan cost exceed thresholds. > > How do you cope with this issue and what have you done to monitor it (logic > wise). > > > > --------------- > Thank You. > -- > //www.freelists.org/webpage/oracle-l > > > -- Andrew W. Kerber 'If at first you dont succeed, dont take up skydiving.' -- //www.freelists.org/webpage/oracle-l