From owner-freebsd-bugs  Mon Aug 27 12:23:32 2001
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Date: Mon, 27 Aug 2001 20:23:26 +0100
From: David Malone <dwmalone@maths.tcd.ie>
To: Martin Blapp <mb@imp.ch>
Cc: freebsd-bugs@FreeBSD.org
Subject: Re: kern/30135: Time drifting on STABLE SMP when calling gettimeofday
Message-ID: <20010827202326.A99505@walton.maths.tcd.ie>
References: <200108271750.f7RHo2j29464@freefall.freebsd.org>
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In-Reply-To: <200108271750.f7RHo2j29464@freefall.freebsd.org>; from mb@imp.ch on Mon, Aug 27, 2001 at 10:50:02AM -0700
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On Mon, Aug 27, 2001 at 10:50:02AM -0700, Martin Blapp wrote:
>  But why does gettimeofday() modify the system counter
>  only on SMP systems ?

Can you see what "sysctl kern.timecounter.hardware" outputs under
SMP and UP on that machine? I'd expect the SMP one to say "i8254"
and the UP one to say "TSC". When running UP you could try changing
the timecounter to whatever is in use under SMP and see if the problem
can then be reproduced under UP.

	David.

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