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Date: Wed, 7 Sep 2011 19:00:22 +0800
From: Wu Fengguang <fengguang.wu@intel.com>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>, Jan Kara <jack@suse.cz>,
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        Greg Thelen <gthelen@google.com>, Minchan Kim <minchan.kim@gmail.com>,
        Vivek Goyal <vgoyal@redhat.com>, Andrea Righi <arighi@develer.com>,
        linux-mm <linux-mm@kvack.org>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 05/18] writeback: per task dirty rate limit
Message-ID: <20110907110022.GA6012@localhost>
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On Wed, Sep 07, 2011 at 03:31:56PM +0800, Peter Zijlstra wrote:
> On Wed, 2011-09-07 at 09:04 +0800, Wu Fengguang wrote:
> 
> > So the sqrt naturally leads to less overheads and more N tolerance for
> > large memory servers, which have large (thresh-freerun) gaps.
> 
> Thanks, and as you say its an initial guess, later refined using patch
> 14.

Yes, exactly.