From mboxrd@z Thu Jan  1 00:00:00 1970
From: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH 2/5] writeback: dirty position control
Date: Fri, 12 Aug 2011 14:54:17 +0200
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Cc: "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,  Andrew
 Morton <akpm@linux-foundation.org>, Jan Kara <jack@suse.cz>, Christoph
 Hellwig <hch@lst.de>, Dave Chinner <david@fromorbit.com>, Greg Thelen
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To: Wu Fengguang <fengguang.wu@intel.com>
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On Fri, 2011-08-12 at 00:56 +0200, Peter Zijlstra wrote:
>=20
>                s - x 3
>  f(x) :=3D  1 + (-----)
>                  d
>=20
btw, if you want steeper slopes for rampup and brake you can add another
factor like:

                 s - x 3
  f(x) :=3D  1 + a(-----)
                   d
=20
And solve the whole f(l)=3D0 thing again to determine d in l and a.

For 0 < a < 1 the slopes increase.

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