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DateWed, 23 Sep 1998 15:42:40 -0500 (CDT)
FromOliver Xymoron <>
SubjectRe: Interesting scheduling times - NOT
On Tue, 22 Sep 1998, Larry McVoy wrote:

> How many times before it sinks in: 77% variance is not cache induced.  If
> that were true, then nothing would be deterministic.  You wouldn't be able
> to say "time make" and expect to get anything like the same number two times
> in a row, yet people do that all the time.

This is not really true, especially for something like make. If you
combine n events of average length t and std dev u, you get an event of
average length n*t, but a smaller std dev - if you multiply a bunch of
bell curves together, you get a tighter curve.  The possible range becomes
larger, sure. 

Not that you would really expect most of events you'd benchmark on a
computer to have a very bell-shaped distribution.

--
 "Love the dolphins," she advised him. "Write by W.A.S.T.E.." 

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