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Date: Wed, 3 Dec 2014 21:55:57 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Linus Torvalds <torvalds@linux-foundation.org>
cc: Dave Jones <davej@redhat.com>, Chris Mason <clm@fb.com>,
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Subject: Re: frequent lockups in 3.18rc4
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On Wed, 3 Dec 2014, Linus Torvalds wrote:
> On Wed, Dec 3, 2014 at 12:09 PM, Dave Jones <davej@redhat.com> wrote:
> >
> > fwiw, there's quite a bit of variance in the delta that seems to show up.
> 
> Yeah, anything from 1 to 251 seconds. That's definitely "quite a bit
> of variance"

But it's always negative, which means HPET is always ahead of
TSC. That excludes pretty much the clocksource watchdog starvation
issue which results in TSC being ahead of HPET due to a HPET
wraparound (which takes ~300s).

Thanks,

	tglx