RE: flush shared_pool and query performance

Thanks, Brandon. I was doing that as a test to see what is an effect of the hard parsing. I did not expect it
to be as significant

thank you

Gene Gurevich

                                                                           
             "Allen, Brandon"                                              
             <Brandon.Allen_at_On                                             
             eNeck.com>                                                 To 
                                       <genegurevich_at_discover.com>,        
             04/03/2008 05:14          <oracle-l_at_freelists.org>            
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                                                                   Subject 
                                       RE: flush shared_pool and query     
                                       performance                         
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           

Yes, I would say .3 seconds is reasonable for a hard parse - that's why we have the shared pool and bind variables to minimize hard parsing. Parse time depends on many things such as the complexity of the query, number of tables joined, optimizer_max_permutations, contention for latches, parsing and IO required for recursive queries on the DD, etc. You might want to try restricting optimizer_max_permutations, especially if you're in pre-9i where it used to default to 80,000 I believe. Maybe check if you're doing dynamic sampling also.

Regards,
Brandon

-----Original Message-----
From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org] On Behalf Of genegurevich_at_discover.com

 Is that reasonable for parsing to take 0.3s?

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