From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joe Thornber <thornber@redhat.com>
Subject: Re: [PATCH 1/2] dm-kcopyd: introduce per-module throttle
 structure
Date: Fri, 10 Jun 2011 11:14:46 +0100
Message-ID: <20110610101446.GB10144@ubuntu>
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Cc: Mikulas Patocka <mpatocka@redhat.com>, "Alasdair G. Kergon" <agk@redhat.com>
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On Fri, Jun 10, 2011 at 11:28:34AM +0200, Lars Ellenberg wrote:
> On Fri, Jun 10, 2011 at 09:44:25AM +0100, Joe Thornber wrote:
> > On Thu, Jun 09, 2011 at 12:08:08PM -0400, Mikulas Patocka wrote:
> > > 
> > > 
> > > On Thu, 9 Jun 2011, Joe Thornber wrote:
> > > > What we're trying to do is avoid kcopyd issuing so much io that it
> > > > interferes with userland io.
> > > 
> > > But you don't know if there is some userland IO or not to the same disk.
> > 
> > None the less, this was the motivation Alasdair gave for wanting this
> > throttling.
> 
> Not sure if it helps,
> but are you familiar with the MD raid rebuild throttling?

Lars,

This is very helpful, thankyou.  Any thoughts on this Mikulas?

- Joe