linux-kernel - Re: AMD Quad Core clock problem?

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Message-ID: <735874.9676.qm@web52502.mail.re2.yahoo.com>
Date:	Fri, 11 Apr 2008 15:09:35 -0700 (PDT)
From:	Marc Perkel <mperkel@...oo.com>
To:	Chris Snook <csnook@...hat.com>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: AMD Quad Core clock problem?


--- Chris Snook <csnook@...hat.com> wrote:

> If it's steadily losing a few seconds every hour,
> it's probably just 
> slightly mis-calibrated hardware.  ntp should fix
> this right up.  If the 
> drift is more extreme than ntp can correct for, or
> the drift keeps 
> changing, or time is jumping around, that is
> definitely something that 
> could be a bug.
> 
> > hpet clockevent registered
> > TSC calibrated against HPET
> > Marking TSC unstable due to TSCs unsynchronized
> 
> It's possible that in future kernels we'll be a few
> clock cycles more 
> accurate in calibrating this on Barcelona chips, but
> calibration is only 
> as good as the standard of comparison.  There will
> always be hardware 
> that's slightly off, so run ntp, or use a nightly
> ntpdate cronjob.  If 
> your time starts drifting drastically or jumping
> around, please yell 
> really loud.
> 
> -- Chris
> 

Is it possible due to calibration that ntpd isn't able
to correct the problem? Is there a setting to make ntp
more agressive?


Marc Perkel
Junk Email Filter dot com
http://www.junkemailfilter.com

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