Re: lost ticks and Hangcheck

[Kurt Wall <kwall@kurtwerks.com>]

On Fri, Aug 19, 2005 at 12:41:07AM -0700, Nathan Becker took 37 lines to write:
> Hi,
> 
> I'm running kernel 2.6.12.5 with x86_64 target on an AMD X2 4800+ and 
> Gigabyte GA-K8NXP-SLI motherboard (bios version F8).  I'm having a problem 
> with lost clock ticks.  The dmesg says
> 
> warning: many lost ticks.
> Your time source seems to be instable or some driver is hogging interupts
> 
> Also if I enable hangcheck, then I get a huge number of Hangcheck messages 
> in dmesg.
> 
> The main other symptom is that the system clock runs fast and 
> inaccurately.  It seems to run more inaccurately when I'm using the CPU, 
> and be basically OK when idling.
> 
> I've tried various workarounds that I found suggested on this list and 
> others but the problem is still there.  I tried using noapic, turning on 
> RTC interrupt, also no_timer_check.  I also tried patching the CPU 
> frequency scaling code with the latest version from the AMD website 
> (1.50.03), and then finally turning that option off. Nothing helped.

I use the no_timer_check kernel parm and that keeps the clock from
running at double speed. I still see some other annoying boot-time
messages related to timers, but at least my time source is sane:

..MP-BIOS bug: 8254 timer not connected to IO-APIC
 failed.
timer doesn't work through the IO-APIC - disabling NMI Watchdog!
Uhhuh. NMI received for unknown reason 3d.
Dazed and confused, but trying to continue
Do you have a strange power saving mode enabled?
 works.
Using local APIC timer interrupts.
Detected 12.436 MHz APIC timer.
testing NMI watchdog ... CPU#0: NMI appears to be stuck (1->1)!

Kurt
-- 
"I think it is true for all _\bn. I was just playing it safe with _\bn >= 3
because I couldn't remember the proof."
		-- Baker, Pure Math 351a