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From: Brian Drummond <brian3@shapes.demon.co.uk>
Newsgroups: comp.lang.ada
Subject: Re: how to analyze clock drift
Date: Wed, 19 Nov 2014 13:08:41 +0000 (UTC)
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Date: 2014-11-19T13:08:41+00:00
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On Wed, 19 Nov 2014 01:41:19 +0000, tmoran wrote:

> Not exactly an Ada question, but...
> The differences between successive values make a sawtooth pattern. Any
> idea why?

If this is on a networked machine, perhaps an NTP daemon is periodically 
resetting one of the clocks being compared.

I've had trouble with that in the past. Experiment would be to turn that 
off (or disconnect networking for a while) and see if there's a steady 
monotonic drift instead...

- Brian