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Date: Mon, 23 Apr 2007 08:42:33 +0000 (UTC)
From: "Bjoern A. Zeeb" <bzeeb-lists@lists.zabbadoz.net>
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Subject: Re: Dell SAS5 Performance Issue
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On Tue, 17 Apr 2007, Matthew Jacob wrote:

Hi,

>> Is there any news on the performance of this card?
>> 
>
> I personally have not been able to reproduce the problem. It seems to
> occur whether in Integrated Raid or not. It seems to be related to
> specific backplanes and drives. It's an important problem to solve I
> agree.

I had done some research a few weeks back and just found the
reference again.

There is a fujitsu-siemens manual[1], and 2.4.8 Disk write caching gives
some hitns on why things are the way they are.

I had also found references, that Windows people have effectively seen
the same problem.

My conclusion is - that's nothing that can be changes with software
easily for the Dell PE 860 with that special chip.

another 0.002ct


References:
[1] http://manuals.fujitsu-siemens.com/serverbooks/content/manuals/english/ir-sas-ug-en.pdf

-- 
Bjoern A. Zeeb				bzeeb at Zabbadoz dot NeT