From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thiemo Nagel <thiemo.nagel@ph.tum.de>
Subject: Re: Raid over 48 disks
Date: Thu, 20 Dec 2007 17:48:36 +0100
Message-ID: <476A9CE4.4010107@ph.tum.de>
References: <00EF99B2-3BCC-4D75-BC75-8F256B0A2476@gmail.com> <Pine.LNX.4.64.0712181325480.13538@p34.internal.lan> <476820B0.9010200@ph.tum.de> <Pine.LNX.4.64.0712181523250.7823@p34.internal.lan> <476837F6.7050404@ph.tum.de> <476936DD.40301@tmr.com>
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Sender: linux-raid-owner@vger.kernel.org
To: Bill Davidsen <davidsen@tmr.com>
Cc: Justin Piszcz <jpiszcz@lucidpixels.com>, Norman Elton <normelton@gmail.com>, linux-raid@vger.kernel.org
List-Id: linux-raid.ids

Bill Davidsen wrote:
>>     16k read    64k write
>>   chunk
>>   size    RAID 5    RAID 6    RAID 5    RAID 6
>>   128k    492    497    268    270
>>   256k    615    530    288    270
>>   512k    625    607    230    174
>>   1024k   650    620    170    75
>>   
> 
> What is your stripe cache size?

I didn't fiddle with the default when I did these tests.

Now (with 256k chunk size) I had

# cat stripe_cache_size
256

but increasing that to 1024 didn't show a noticeable improvement for 
reading.  Still around 550MB/s.

Kind regards,

Thiemo