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From: John Hughes <john@Calva.COM>
To: Bill Davidsen <davidsen@tmr.com>
Cc: mark delfman <markdelfman@googlemail.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 15:39:18 +0100	[thread overview]
Message-ID: <4AF19216.30300@Calva.COM> (raw)
In-Reply-To: <4AF18A39.6010404@tmr.com>

Bill Davidsen wrote:
> mark delfman wrote:
>> Hi... I am wondering if anyone can offer some advice on MD performance
>> related to CPU (speed and or cores).  
>
> You didn't ask: if you use ext[34] filesystems, there is a gain to be 
> had from tuning the stripe and stride parameters, at least for large 
> sequential io. My measurements were on 2.6.26, so are out of date, but 
> less head motion is always better. 
An external journal can be a huge win for ext3 if you are doing lots of 
file creates/deletes.  (Striped raid, i.e. raid0/raid5/raid6/raid10 
doesn't help the journal much as it is used sequentially.  In my tests 
putting the journal on a raid1 and the rest of the fs on a raid10 makes 
things go much faster.  If you have enough disks of course :-))



  parent reply	other threads:[~2009-11-04 14:39 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
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   ` John Hughes [this message]
2009-11-09 17:24     ` MD performance options: More CPU’s or more Hz’s? 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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