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Date: Fri, 29 Apr 2005 07:09:28 +0300
From: Petri Helenius <pete@he.iki.fi>
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To: Eric Anderson <anderson@centtech.com>
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cc: Steven Hartland <killing@multiplay.co.uk>
cc: Peter Losher <Peter_Losher@isc.org>
Subject: Re: Very low disk performance Highpoint 1820a
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Eric Anderson wrote:

>
> I'm using fiber channel SATA, and I get 2x write as I do read, which 
> doesn't make sense to me.  What kind of write speeds do you get?  My 
> tiny brain tells me that reads should be faster than writes with a RAID5.
>
I'm seeing similar sequential performance on RELENG_5_3 and RELENG_5_4 
on dual-Xeons using 3ware controllers so it does not seem to be a driver 
issue but somewhere else in the architechture. Depending on the array 
configuration, 40-60MB/s reads and 100-160MB/s writes. The write 
performance is as expected but the read performance should be above the 
write performance.

Pete