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Subject: Re: time jumps forward/backwards
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Benjamin Gamsa <ben@somanetworks.com>
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Date: Tue, 01 Sep 2009 20:49:14 +1000
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Cc: Paul Mackerras <paulus@samba.org>, linuxppc-dev@lists.ozlabs.org,
	Sean MacLennan <smaclennan@pikatech.com>
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On Mon, 2009-08-31 at 23:57 -0400, Benjamin Gamsa wrote:
> Sean MacLennan wrote:
> > On Mon, 31 Aug 2009 22:20:00 -0400
> > Benjamin Gamsa <ben@somanetworks.com> wrote:
> > 
> >> For what it's worth, the problem occurs even when ntp is not even
> >> started.
> > 
> > This is grasping, but could it have anything to do with the jiffies
> > wrapping near startup?
> > 
> 
> I don't know how to test it, but I don't think so, since there are 
> multiple of these glitches over an extended period of time.

I'm not familiar with all the FSL processor variants, but is this
an UP or an SMP platform ? In the later case, are all the core timebases
properly synchronized ?

Cheers,
Ben.