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Date: Tue, 22 Jan 2013 08:53:28 -0500
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Subject: Re: time issues and ZFS
From: Ryan Stone <rysto32@gmail.com>
To: Julian Stecklina <jsteckli@os.inf.tu-dresden.de>
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On Tue, Jan 22, 2013 at 7:27 AM, Julian Stecklina <
jsteckli@os.inf.tu-dresden.de> wrote:

> Does anyone know why the LAPIC is given a lower priority than HPET in
> this case? If you have an LAPIC, it should always be prefered to HPET,
> unless something is seriously wrong with it...
>

On many processors the lapic timer does not work correctly in states lower
than C1.  There are many processors that will automatically enter a "C1E"
mode when the processor is idle, and in that state I have seen the lapic
timer run slower than the programmed frequency, causing time to move to
slowly on idle FreeBSD systems.