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From: Simon Wright <simon.j.wright@mac.com>
Newsgroups: comp.lang.ada
Subject: Re: real_time.clock is not monotonic
Date: Mon, 26 Feb 2007 20:59:56 +0000
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Date: 2007-02-26T20:59:56+00:00
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Florian Weimer <fw@deneb.enyo.de> writes:

> * Simon Wright:
>
>>         ("rdtsc" & ASCII.LF & ASCII.HT &
>
> This is not monotonic, either, because on some (most?)
> architectures, the cycle counters of the different CPUs are not
> synchronized.

As I said, it was for hi-res timing, and if you get swapped in the
timed code the result is an outlier even if there's onlu one CPU.