Clock stalls on Sabertooth 990FX

[Joe Schaefer]

On Mon, Aug 15, 2011 at 9:31 AM, Joe Schaefer <joesuf4 at gmail.com> wrote:
> On Mon, Aug 15, 2011 at 8:32 AM, Andriy Gapon <avg at freebsd.org> wrote:
>> on 13/08/2011 20:16 Joe Schaefer said the following:
>>> Brand new machine with a Phenom II X6 1100T and under chronic load
>>> the clock will stop running periodically until the machine eventually completely
>>> freezes.  Note: during these stalls the kernel is still running, the
>>> machine is still
>>> mostly responsive, it's just that the clock is frozen in time.
>>>
>>> I've disabled Turbo mode in the bios and toyed with just about every
>>> other setting but nothing seems to resolve this problem.  Based on the behavior
>>> of the machine (just making buildworld will eventually kill it, upping
>>> the -j flag
>>> just kills it faster), I'm guessing it has something to do with the
>>> Digi+ VRM features
>>> but again nothing I've tried modifying in the bios seems to help.
>>>
>>> I've tried both 8.2-RELEASE and FreeBSD 9 (head).  Running head now with
>>> a dtrace enabled kernel.
>>>
>>> Suggestions?
>>
>> On head, start with checking what source is used for driving clocks:
>> sysctl kern.eventtimer
>
> % sysctl kern.eventtimer                                  [master]
> kern.eventtimer.choice: HPET(450) HPET1(450) HPET2(450) LAPIC(400)
> i8254(100) RTC(0)
> kern.eventtimer.et.LAPIC.flags: 15
> kern.eventtimer.et.LAPIC.frequency: 0
> kern.eventtimer.et.LAPIC.quality: 400
> kern.eventtimer.et.HPET.flags: 3
> kern.eventtimer.et.HPET.frequency: 14318180
> kern.eventtimer.et.HPET.quality: 450
> kern.eventtimer.et.HPET1.flags: 3
> kern.eventtimer.et.HPET1.frequency: 14318180
> kern.eventtimer.et.HPET1.quality: 450
> kern.eventtimer.et.HPET2.flags: 3
> kern.eventtimer.et.HPET2.frequency: 14318180
> kern.eventtimer.et.HPET2.quality: 450
> kern.eventtimer.et.i8254.flags: 1
> kern.eventtimer.et.i8254.frequency: 1193182
> kern.eventtimer.et.i8254.quality: 100
> kern.eventtimer.et.RTC.flags: 17
> kern.eventtimer.et.RTC.frequency: 32768
> kern.eventtimer.et.RTC.quality: 0
> kern.eventtimer.periodic: 0
> kern.eventtimer.timer: HPET
   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Changing this to "i8254" seems to have resolved the stalls.
I'm running buildworld -j12 without issue.  More than willing
to test out a patch or two against head if anyone's still
interested, otherwise I've thrown the change into loader.conf
and will move along quietly.