From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH] improve the performance of large sequential write NFS
 workloads
Date: Tue, 22 Dec 2009 13:38:35 +0100
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Cc: Steve Rago <sar-a+KepyhlMvJWk0Htik3J/w@public.gmane.org>,
	Wu Fengguang <fengguang.wu@intel.com>,
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	"jens.axboe" <jens.axboe@oracle.com>,
	Peter Staubach <staubach@redhat.com>
To: Jan Kara <jack@suse.cz>
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On Tue, 2009-12-22 at 13:25 +0100, Jan Kara wrote:
>   I believe that if we had per-bdi dirty_background_ratio and set it low
> for NFS's bdi, 

There's two things there I think:
 1) bdi_background
 2) different background ratios per bdi

1) could be 'trivially' done much like we do bdi_dirty in
get_dirty_limits().

2) I'm not at all convinced we want to go there.