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From: Emanuel Berg <embe8573@student.uu.se>
Newsgroups: comp.lang.ada
Subject: Re: how to analyze clock drift
Date: Fri, 21 Nov 2014 22:15:15 +0100
Organization: Aioe.org NNTP Server
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Xref: news.eternal-september.org comp.lang.ada:23616
Date: 2014-11-21T22:15:15+01:00
List-Id: <comp.lang.ada>

Dennis Lee Bieber <wlfraed@ix.netcom.com> writes:

> To measure actual clock variation you MUST have an
> independent time-base for comparison.

I'm starting to think this is a good idea. I thought
the problem was sleep_until specifically, not all the
C++ <chrono> stuff, in what case using that to
diagnose itself of course can't be done.

So then, where do I get a better clock?

My Linux gets it time from this command, I think (it
was a while since a mucked around that stuff)

    ntpdate pool.ntp.org

Is that considered reliable to the point it makes
sense diagnosing sleep_until with that instead of the
C++'s now()?

-- 
underground experts united