Re: Performance problem

From: Robert Klemme <bob.news_at_gmx.net>
Date: Tue, 6 Dec 2005 18:35:12 +0100
Message-ID: <3vm0elF16h9paU1@individual.net>

Jim Kennedy wrote:

> "Tony" <trindata_at_bellsouth.net> wrote in message
> news:Ildlf.19132$wi2.16460_at_bignews1.bellsouth.net...

>> After devoting a great deal of effort to tune a particular batch
>> process some physical changes were made to our environment. The
>> result is that our batch job now takes twice the amount of time to
>> execute (7 hours instead of
>> 3.5!)..
>>
>>
>>
>> The changes made were as follows:
>>
>> 1.. 1 GB Nics were replaced by 100 MB cards
>> 2.. 15k rpm smaller drives were replaced by larger 10k rpm drives
>> 3.. Disk layouts were changed to make use of the larger drives
>> Other than that, the application has not been changed. The
>> operating system and Oracle release have not been upgraded either.
>> I am trying to make a case for returning the environment to its
>> previous state (Nics and drive speed) while collecting information
>> using in-house tools such as Statspack, TKPROF etc. In the absence
>> of detailed analysis of the previous runs (3.5 hours) what can I use
>> to highlight the negative impact of the changes made to our
>> environment?
>>
>>

> You need a benchmark that was on the old system and on the new
> system.  I would think the batch process you cite is that benchmark.
> Why do people think replacing drives with slower ones will speed
> things up?  The NIC cards may not make any different.  You could
> measure the IO and max IO rate on the drives in stats pack but what
> do you have it to compare it to?

Also, Tony, why did you downgrade network connectivity from 1GB cards to 100MB cards? Items 1 and 2 on your list were all about replacing hardware with slower hardware. No surprize that you experience a slowdown...

Kind regards

    robert Received on Tue Dec 06 2005 - 11:35:12 CST