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Date: Fri, 2 Jul 2004 11:21:59 +0200
From: Markus Schaber <schabios@logi-track.com>
To: Markus Schaber <schabios@logi-track.com>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: CCISS driver and Caching (was: Block Device Caching)
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Hello,

We did some additional tests, and just learned that the underlying raid
itsself is not cached by the linux kernel:


bear:~/readcachetest# ./readcache /dev/cciss/c0d0p2 1000
frist run needed 16.006950 seconds, this is 62.472863 MBytes/Sec
second run needed 15.919336 seconds, this is 62.816690 MBytes/Sec
third run needed 15.830325 seconds, this is 63.169897 MBytes/Sec

So we now think it's some problem of the cciss driver, and not of lvm.

weird...

Markus


-- 
markus schaber | dipl. informatiker
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