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To: Andriy Gapon <avg@FreeBSD.org>
cc: freebsd-hackers <freebsd-hackers@FreeBSD.org>
Subject: Re: instability of timekeeping
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From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
References: <56261398.60102@FreeBSD.org> <56261FE6.90302@FreeBSD.org>
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--------
In message <56261FE6.90302@FreeBSD.org>, Andriy Gapon writes:

>I performed a small observation.  With ntpd disabled I ran `ntpdate -d` at 10
>second intervals in a loop (done via `sleep 10`).  It looks like for about 25
>minutes the time offset between a reference server and my machine was quite
>stable. But then it sort of jumped about 2.5 seconds between two consecutive
>ntpdate invocations.

Pure guesswork:  Somebody may have börked the code to wind up timecounters.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.