Re: Poor performance after oracle 8i upgrade

rreeve_at_goldcoast.qld.gov.au (Ruth) wrote in 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

You need more than the current wait events to diagnose the problem accurately. Do you have the same report from prior to the upgrade? If you are taking snapshots regularly you should. You need to see what changed

Other than that, the other suggestions are probably valid. Regather statistics and see if that helps.

-- 
Chuck
Remove "_nospam" to reply by email