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Subject: Re: [PATCH 2/5] writeback: dirty position control
From: Peter Zijlstra <peterz@infradead.org>
To: Wu Fengguang <fengguang.wu@intel.com>
Cc: "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
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Date: Fri, 12 Aug 2011 14:54:17 +0200
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On Fri, 2011-08-12 at 00:56 +0200, Peter Zijlstra wrote:
> 
>                s - x 3
>  f(x) :=  1 + (-----)
>                  d
> 
btw, if you want steeper slopes for rampup and brake you can add another
factor like:

                 s - x 3
  f(x) :=  1 + a(-----)
                   d
 
And solve the whole f(l)=0 thing again to determine d in l and a.

For 0 < a < 1 the slopes increase.