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Date: Wed, 16 Apr 1997 13:48:15 -0400 (EDT)
From: Thomas David Rivers <ponds!rivers@dg-rtp.dg.com>
Message-Id: <199704161748.NAA03099@lakes.water.net>
To: ponds!freefall.cdrom.com!freebsd-hackers, ponds!quickweb.com!mark,
        ponds!lakes.water.net!rivers
Subject: Re: "calcru: negative time" messages (FreeBSD-2.2.1)
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> On Wed, Apr 09, 1997 at 04:36:43PM -0400, Thomas David Rivers wrote:
> > 
> > I'm getting these messages after my install of 2.2.1:
> > 
> > Apr  9 16:30:25 numb /kernel: calcru: negative time: -330 usec
> > Apr  9 16:30:25 numb /kernel: calcru: negative time: -330 usec
> > 
> >  They don't seem to obviously coincide with anythine; can anyone
> > shed some light on this?
> 
> Do you have:
> options		"CLK_USE_I586_CALIBRATION"
> 
> in your kernel? On my PPro 150, without this I would randomly get these
> messages all the time. My CPU speed detection would vary greatly as well.
> Since I added the above option, my CPU speed is detected correctly on
> boot, and I don't get ANY calcru: negative time:  messsages! Happy.
> 
> Maybe this is it? I'm assuming it's only valid for Pentium and above CPUs,
> however.
> 
> -Mark
>

 No, I hadn't tried that.  At the time, I was running a GENERIC 2.2.1
kernel.

 I did rebuild a kernel with Bruce's fix to isa/clock.c; and haven't
seen the problem  since - could it have been blocked RTC interrupts?

	- Dave Rivers -