From: jim owens <jowens@hp.com>
To: mark delfman <markdelfman@googlemail.com>
Cc: Bill Davidsen <davidsen@tmr.com>,
Linux RAID Mailing List <linux-raid@vger.kernel.org>
Subject: Re: MD performance options: More CPU’s or more Hz’s?
Date: Wed, 04 Nov 2009 10:56:54 -0500 [thread overview]
Message-ID: <4AF1A446.700@hp.com> (raw)
In-Reply-To: <4AF1A1B4.2030405@hp.com>
jim owens wrote:
>> So the proper comparison of raid6 software overhead is to
>> run the same application writing a fixed large amount of data
>> to 4 drives at raid0 and the same 4 drives at raid6.
Actually, it is probably better to run the application with
2 X data to raid0 and 1 X data to raid6
so the amount of written disk data is the same.
That way the comparison will remove the bus/disk difference
caused by sending different amounts of data and:
overhead = raid6_time - raid0_time;
jim
next prev parent reply other threads:[~2009-11-04 15:56 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-11-04 9:49 MD performance options: More CPU’s or more Hz’s? mark delfman
2009-11-04 12:08 ` Sujit K M
2009-11-04 12:19 ` mark delfman
2009-11-04 14:05 ` Bill Davidsen
2009-11-04 14:34 ` mark delfman
2009-11-04 15:41 ` jim owens
2009-11-04 15:45 ` jim owens
2009-11-04 15:56 ` jim owens [this message]
2009-11-04 17:26 ` mark delfman
2009-11-04 19:09 ` jim owens
2009-11-05 12:34 ` MD performance options: More CPUs or more Hzs? Goswin von Brederlow
2009-11-04 14:39 ` MD performance options: More CPU’s or more Hz’s? John Hughes
2009-11-09 17:24 ` Bill Davidsen
2009-11-09 17:37 ` John Hughes
2009-11-04 15:01 ` MD performance options: More CPU’s or more Hz’s? Goswin von Brederlow
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