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RE: Slow Database Aft Upgrade from 8i to 9.2

From: Powell, Mark D <>
Date: Thu, 21 Jul 2005 16:07:29 -0400
Message-ID: <>

In my experience not only does 9i normally require a larger shared pool to run the same applications as 8i, if you move from 32 bit to 64 bit this will likely require additional memory be allocated to the shared pool also.

If you do both at once then doubling is not out of the question. It depends on your application, concurrent user load, and how much slack you had in your 8i system, but normally more memory is required by 9i over 8i.

After a major upgrade changes in optimizer behavior could require tuning or retuning SQL. There are over a dozen optimizer related underbar
(hidden) parameters that defaulted off in 8i and which default to on in
9i. Some sites were bitten by bugs related to some of these. However if you went from 8i to 9.2 you should have gone all the way to
(or at least .5) and most of these bugs are fixed by then.

HTH -- Mark D Powell --

-----Original Message-----
[] On Behalf Of Burton, Laura Sent: Thursday, July 21, 2005 2:54 PM
Subject: Slow Database Aft Upgrade from 8i to 9.2

Can someone direct me to a place to troubleshoot your database? Is there a way to check for 'Memory Leaks'? I have a tuning book and have been running scripts to find how much is being used, what statements are the worst, etc., but is there a 'common' size for the Shared Pool, Large Pool, Sort, etc? I know it depends on the size of the database. I guess I am just looking for a starting point, i.e. if small blah, blah; if large blah blah, or large pool is ??% the size of the Shared Pool and total db memory should not be more than ??% of physical memory.

Thanks, Laura

Received on Thu Jul 21 2005 - 15:10:04 CDT

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