Re: Re: 10046 event is useless in 9.2.0.4 version for response time measuring !!!

From: Niall Litchfield <niall.litchfield_at_gmail.com>
Date: Tue, 3 Aug 2004 10:04:29 +0100
Message-ID: <7765c8970408030204388d396b@mail.gmail.com>

On Mon, 02 Aug 2004 14:27:21 -0600, Daniel Fink <daniel.fink_at_sun.com> wrote:
> If you can extract the performance problem from production and replicate it on a non-production system, is the 6x timing issue
> really an issue? If the 6x stays constant, then you can still compare apples to apples.

Unfortunately the factor by which times are increased is not constant. The overhead comes from the row-source execution statistics which means (in general) that operations that change between row sources frequently will suffer to a greater extent than operations that don't.

So hash joins for example will look more desirable (to the analyst - not the CBO) than NL.

-- 
Niall Litchfield
Oracle DBA
http://www.niall.litchfield.dial.pipex.com
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Received on Tue Aug 03 2004 - 04:00:27 CDT