From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paul Clements <Paul.Clements@SteelEye.com>
Subject: Re: poor performance with raid1 / raid0
Date: Wed, 18 Jun 2003 10:39:37 -0400
Sender: linux-raid-owner@vger.kernel.org
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To: Per Andreas Buer <perbu@linpro.no>
Cc: Andrew Rechenberg <arechenberg@shermfin.com>, linux-raid@vger.kernel.org
List-Id: linux-raid.ids

Per Andreas Buer wrote:
> 
> Andrew Rechenberg <arechenberg@shermfin.com> writes:
> 
> > Check /proc/sys/dev/raid/speed_limit_[min|max].  If they are set too low
> > then your re-mirror will behave as such.  To change just echo a new
> > value:
> >
> > echo 30000 > /proc/sys/dev/raid/speed_limit_min
> > echo 50000 > /proc/sys/dev/raid/speed_limit_max
> >
> 
> I did so - and now:
> 
> md6 : active raid1 md16[2] sdd6[0]
>       117185984 blocks [2/1] [U_]
>       [>....................]  recovery =  0.1% (229120/117185984)
> finish=59.5min speed=32731K/sec

That's probably because you just lowered the values. The maximum is
normally 100000. To check what the default values are, reboot and do:

cat /proc/sys/dev/raid/speed_limit_*

Then echo a _larger_ number into those files.

There is no absolute maximum value (except maybe 2^32), so don't be
afraid to raise the values to 10 or 100 times what they were. That
should ensure that your resync speed is close to its theoretical
maximum.

--
Paul