From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bill Davidsen <davidsen@tmr.com>
Subject: Re: stripe_cache_size and performance
Date: Mon, 25 Jun 2007 12:48:21 -0400
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To: Justin Piszcz <jpiszcz@lucidpixels.com>
Cc: Raz <raziebe@gmail.com>, jnelson-linux-raid@jamponi.net, linux-raid@vger.kernel.org
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Justin Piszcz wrote:
> I have found a 16MB stripe_cache_size results in optimal performance 
> after testing many many values :)

We have discussed this before, my experience has been that after 8 x 
stripe size the performance gains hit diminishing returns, particularly 
for typical write instead of big aligned blocks, possibly with O_DIRECT. 
I would suggest that as a target even on a low memory machine.

Do your tests show similar? I was only able to test three and four drive 
setups using dedicated drives.

-- 
bill davidsen <davidsen@tmr.com>
  CTO TMR Associates, Inc
  Doing interesting things with small computers since 1979