Re: Can anyone explain this huge increase in logical I./O....?

From: Mark D Powell <Mark.Powell_at_eds.com>
Date: 23 Oct 2006 13:34:27 -0700
Message-ID: <1161635667.422823.301270@f16g2000cwb.googlegroups.com>

mccmx_at_hotmail.com wrote:
> > I would also look at why the results in the *query* columns are so
> > different:
> > 1,613,065 for the fast running
> > and
> > 40,083,925 for the slow running
> > query. There is one order of magnitude difference there.
>
> Thats exactly why I posted the question. The whole point of this
> thread is to determine why the query count was over 20 times more.
>
> Matt

Grabbing the statistics before and after the query as suggested would indeed help to see what is going on in the database while the query is running.

I suspect that either there is an update process you are unaware of or else the blocks are dirty and delayed block cleanout is taking place.

A trace with wait events enabled might also allow you to more positively identify the true cause of the problem.

HTH -- Mark D Powell -- Received on Mon Oct 23 2006 - 15:34:27 CDT