Messages in this thread | | | Subject | Re: 2.6.25.9: system clocks works normally then speeds up 4x... | From | Philippe Troin <> | Date | 09 Jul 2008 15:50:18 -0700 |
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john stultz <johnstul@us.ibm.com> writes:
> On Wed, 2008-07-09 at 13:53 -0700, Philippe Troin wrote: > > john stultz <johnstul@us.ibm.com> writes: > > > > > When you're seeing the issue, can you do the following: > > > cat /proc/interrupts > interrupts > > > > > > <wait 10 seconds by your wristwatch> > > > > > > cat /proc/interrupts >> interrupts > > > > > > And send the results? > > > > There you are: > > > > CPU0 CPU1 > > 0: 353 0 IO-APIC-edge timer > > LOC: 546305845 33155722 Local timer interrupts > > Roughly 10 seconds later: > > 0: 353 0 IO-APIC-edge timer > > LOC: 546361653 33156517 Local timer interrupts > > Huh. So that's a diff of: > LOCdiff 55808 795 > > So that's 55 seconds worth of ticks on cpu0 and not one on cpu1. So yea, > something seems off with your timer interrupts.
On the still-wedged system, if I use 'tsc' as my clocksource (and the time flows "normally", I still see the same kind of diff (same order of magnitude).
> > > Could you also try booting with noapic to see if that changes anything? > > > > Sure. This will mean I will lose the "wedged" system. Is there > > anything else that needs to be checked on it before I lose the broken > > state? > > Also keep in mind that the symptoms take a while to manifest > > themselves (a few days typically).
> I can't think of anything right off. But maybe we should give some > others a chance to look. > > I would like to see the same /proc/interrupt data when the system is > properly functioning as well. So whenever you do reboot, that would be > interesting to me.
So I just rebooted.
Now I see:
Wed Jul 9 15:47:59 PDT 2008: LOC: 2050354 2050438 Local timer interrupts Wed Jul 9 15:48:09 PDT 2008: LOC: 2060368 2060452 Local timer interrupts
So about 10000 timer interrupts for 10 seconds, which sounds good with HZ=1000.
I've rebooted without noapic, and I will monitor and log these numbers and see how it goes.
I'm not sure noapic could help here as obviously the interrupts are routed correctly, at least initially.
Phil.
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