Re: [PATCH 2/5] writeback: dirty position control

From: Wu Fengguang
Date: Fri Aug 12 2011 - 09:00:07 EST


On Fri, Aug 12, 2011 at 08:54:17PM +0800, Peter Zijlstra wrote:
> 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.

Yes, we can leave it as a future tuning option. For now I'm pretty
satisfied with the current function's shape :)

Thanks,
Fengguang
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