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Date: Wed, 16 Jan 2002 15:02:37 -0800 (PST)
From: Alexei Podtelezhnikov <apodtele@mccammon.ucsd.edu>
X-X-Sender: apodtele@chemcca18.ucsd.edu
To: Davide Libenzi <davidel@xmailserver.org>
cc: linux-kernel@vger.kernel.org
Subject: Re: [o(1) sched J0] higher priority smaller timeslices, in fact
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Message-ID: <Pine.LNX.4.44.0201161501430.3828-100000@chemcca18.ucsd.edu>
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man nice helped. Thanks!

On Wed, 16 Jan 2002, Davide Libenzi wrote:

> On Wed, 16 Jan 2002, Alexei Podtelezhnikov wrote:
> 
> >
> > The comment and the actual macros are inconsistent.
> > positive number * (19-n) is a decreasing function of n!
> 
> # man nice
> 
> 
> > + * The higher a process's priority, the bigger timeslices
> > + * it gets during one round of execution. But even the lowest
> > + * priority process gets MIN_TIMESLICE worth of execution time.
> > + */
> >
> > -#define NICE_TO_TIMESLICE(n)   (MIN_TIMESLICE + \
> > -	((MAX_TIMESLICE - MIN_TIMESLICE) * (19 - (n))) / 39)
> > +#define NICE_TO_TIMESLICE(n) (MIN_TIMESLICE + \
> > +	((MAX_TIMESLICE - MIN_TIMESLICE) * (19-(n))) / 39)
> >
> > I still suggest a different set as faster and more readable at least to
> > me. Just two operations instead of 4!
> 
> this seems quite readable to me, it's the equation at page 1 of any know
> linear geometry book.
> 
> 
> 
> 
> - Davide
> 
> 
> 

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