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From: Daniel Phillips <phillips@arcor.de>
To: Linus Torvalds <torvalds@transmeta.com>,
       "Richard B. Johnson" <root@chaos.analogic.com>
Subject: Re: HZ, preferably as small as possible
Date: Wed, 17 Jul 2002 23:16:25 +0200
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On Wednesday 17 July 2002 23:02, Linus Torvalds wrote:
> On Wed, 17 Jul 2002, Richard B. Johnson wrote:
> >
> > It is hardly novel and I can't imagine how Bresenham or whomever
> > could make such a claim to the obvious. Even the DOS writer(s) used
> > this technique to get one-second time intervals from the 18.206
> > ticks/per second.
> 
> Ehh.. Look at _existing_ linux code to do exactly the same.
> 
> See update_wall_time_one_tick() and second_overflow() (which does a lot
> more besides, but it does largely boil down to this "average fractions
> using basic integer math" thing.

I see lots of stuff in there all right, but I don't see anything that
implements the numerator/denominator error analysis technique I
described above.  Maybe I just didn't look hard enough.

-- 
Daniel
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