Re: Poor performance after oracle 8i upgrade

rreeve_at_goldcoast.qld.gov.au (Ruth) wrote in message news:<7d088242.0409062036.c87f0e1_at_posting.google.com>...
> Hi All
>
> I am not a DBA, but a unix administrator.
>
> After our DBA's upgraded from oracle 8.0.5 to oracle 8.1.7.4 on our
> test server, we have noticed a big slow down in our application
> (acocobol). From ~10mins to ~45mins.
>
>
> Server info:
> HP Proliant ML350G3
> 1024MB Ram
> 1 x Intel Xeon 2.8GHz processor
> Unixware 7.1.1
>
>
> The DBA's have run a report which indicates an I/O problem.
>
> Total Wait
> wait Waits
> Event Waits Timeouts Time (cs)
> (ms) /txn
> ---------------------------- ------------ ---------- -----------
> ------ ------
> log file sync 90,709 0 123,003
> 14 1.0
> log file parallel write 90,719 0 121,555
> 13 1.0
>
>
>
> Our redo logs are on a mirror.
>
>
> We also have tried setting OPTIMIZER_FEATURES_ENABLE=8.0.0
> but no luck .....
>
>
> The DBA's tried the upgrade 2 different ways
> 1. upgrade original database from 8.0.5 to 8.1.7.4
> 2. built brand new database from scratch then importing the data.
>
> Both ways have the same performance problem.
>
>
> Does anyone have any idea why this is occurring on 8.1.7.4 and not on
> 8.0.5, and how we can fix it.
>
> thankyou
>
> regards
> Ruth

Ruth, based on experience I know that anytime you perform a major Oracle RDBMS upgrade that a query or two may go to lunch. Find the SQL that is not performing well and tune it.

The first step is updating the statistics and then compare job run times to their pre-update job run times. Tune those that differ to the worse.

HTH -- Mark D Powell -- Received on Tue Sep 07 2004 - 08:35:04 CDT