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Re: DBWR Tuning

From: DA Morgan <>
Date: Mon, 13 Dec 2004 17:47:42 -0800
Message-ID: <1102988750.978267@yasure>

Denis Do wrote:

> Hi Nial!
> Thanks for your comments, mate.
> First of all, you have demonstrated different approach in
> evaluation of potential bottlenecks, - I do not think it
> is wrong, it is just different.
> So, I am fine with it:-)
> Second, your comments obviously make point, but as you could
> see from my post, I was trying to look at all aspects
> together - disks, CPU, Memory and available latches number.
> In your answer, you are
> pointing to each of these alone, i.e. 8 cpus - ONLY then you
> can add one more DBWriter. I think differently, so my
> opinion still to run at least 2 DBWriters.
> If you will see some negative impact, no problem - go back
> to single writer and that is it. But I always running
> DBWriters in pairs - and I always see improvement in
> performance. At least it works for me - why not try both of
> our advices? Author of original post was seeking for them
> - we gave 2 diferent :-) - so now he can try and decide.
> Besides, if you will have a look at more old books ( Like
> Jason Couchman's Ora 8 DBa Cert. Guide - you will find there
> on pg 904 (top) explicit confirmation of my theory.
> Anyway, lets this topic to die in peace :-)
> Have a great day!

I'm fine with it dying but want to say that, from experience, there is no hard and much good that comes from experimentation. All guidelines are just that ... guidelines. 8 is not more a "fact" than is any other integer. It is always best to test modifications to configurations.

Daniel A. Morgan
University of Washington
(replace 'x' with 'u' to respond)
Received on Mon Dec 13 2004 - 19:47:42 CST

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