From owner-freebsd-current  Sun Jul 19 23:43:05 1998
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	Mon, 20 Jul 1998 16:42:39 +1000
Date: Mon, 20 Jul 1998 16:42:39 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199807200642.QAA17899@godzilla.zeta.org.au>
To: bde@zeta.org.au, brian@Awfulhak.org
Subject: Re: tickadj -t not changing tick
Cc: freebsd-current@FreeBSD.ORG, jak@cetlink.net
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>APM seems to be preventing use of the TSC timecounter.  Otherwise
>the clock would go non-backwards 233/17 faster :-).

The whole problem may be caused by APM.  APM's time handling is of low
quality.  Among other bugs, it assumes that inittodr() has a resolution
of about 1 usec.  inittodr() actually has a resolution of about 1 second,
so the time may be set wrong by up to +- 1 second after even a short
suspension.  This may cause the time to go backwards if the suspension
period is shorter than 1 second.

Bruce

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