RE: flush shared_pool and query performance

From: Bobak, Mark <Mark.Bobak_at_proquest.com>
Date: Thu, 3 Apr 2008 17:59:31 -0400
Message-ID: <667C10D184B2674A82068E06A78382B51DD2534A@AAPQMAILBX01V.proque.st>


Sure, I don't think that's unreasonable at all. As an added confirmation, if you have 0.01 secs, and then you flush and first execution is 0.3 secs, does the second execution after the flush go back to 0.01 secs? If so, then the difference is the hard parse.

-Mark

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Mark J. Bobak
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-----Original Message-----

From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of genegurevich_at_discover.com Sent: Thursday, April 03, 2008 5:40 PM
To: oracle-l_at_freelists.org
Subject: flush shared_pool and query performance

Hi all:

I am noticing that the same SQL executed before and after 'alter system flush shared_pool' completes in VASTLY
different time - 0.01s before the command and 0.3s after the command. I wonder why is that. When I flush the
shared_pool, the library cache is flushed and so my SQL needs to be reparsed. Is that reasonable for parsing to take 0.3s?

thank you

Gene Gurevich

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http://www.freelists.org/webpage/oracle-l Received on Thu Apr 03 2008 - 16:59:31 CDT

Original text of this message