Re: Average physical read times

I have seen as small as 2 ms, rarely about 10 ms. Did you check and see if the DBFMBRC might be set too high?

On Wed, Sep 24, 2008 at 11:17 AM, Daniel Fink <daniel.fink_at_optimaldba.com>wrote:

> In a recent optimization effort, I found what I think are high physical
> read times. For example, a single block read was averaging 11 milliseconds
> with a max of over 1 second (tkprof output). For this session, single block
> reads consumed over 80% of the response time, so this is of concern.
>
> We are running Oracle 10gr1 on AIX with an IBM storage array (shared
> amongst many servers). I suspect there is some optimization that can be done
> at the storage array level. If 11 milliseconds is well above average, this
> will help in engaging that team in the process.
>
> For those of you running statspack. AWR or other monitoring tools, what are
> the average single block read times you are encountering on a good system?
> If you are running on an IBM storage array, have you found any specific
> issues/fixes?
>
> Regards,
> Daniel Fink
>
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> Daniel Fink
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>

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