Timed_statistics

From: Norman Dunbar <Norman.Dunbar_at_lfs.co.uk>
Date: Thu, 17 Oct 2002 16:33:40 +0100
Message-ID: <E2F6A70FE45242488C865C3BC1245DA702CCBF83@lnewton.leeds.lfs.co.uk>

Evening all,

I've got a 'friend' who has a database at 8172 on a SUN box. This database is having some preformance problems. Running Statspack snapshots every half hour is fine. Doing it with timed_statitics = true is absolutely screweing (technical term) the database.
Response times plummet, users complain etc etc.

I've never had any problems with T_S before myself, and I'm a bit stumped as to why the severe effect with this database. We know that there is a (serios) disc I/O problem (top wait is for 90 mins out of an 8 hour uptime on 'db file sequential read') but CPU is mainly idle (8 processors, 2GB RAM).
Discs are RAW and I've got him checking if it is software mirroring or not, and if so is DIRTY REGION LOGGING on, and if so, where are the logging files (Thanks for that one Jonathan - last year at the Belfry !)

Any pointers please - the info from T_S is much better than without it, but it is almost impossible to turn it on for long.

Cheers,
Norman.

Norman Dunbar
Database/Unix administrator
Lynx Financial Systems Ltd.
mailto:Norman.Dunbar_at_LFS.co.uk

Tel: 0113 289 6265
Fax: 0113 289 3146
URL: http://www.Lynx-FS.com


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Received on Thu Oct 17 2002 - 10:33:40 CDT