FreeBSD 7.0 interrupt storm with irq0: clk

[Erik Trulsson]

On Sun, Oct 14, 2007 at 01:03:44PM -0700, Abdullah Ibn Hamad Al-Marri wrote:
> On 2007-Oct-14 15:36:39 +0300, Abdullah Ibn Hamad Al-Marri
>  <almarrie at gmail.com> wrote:
> >On 10/13/07, Nate Lawson <nate at root.org> wrote:
> >> Rolf Witt wrote:
> >> > Abdullah Ibn Hamad Al-Marri schrieb:
> >> >> Hello,
> >> >>
> >> >> I'm getting interrupt storm lately.
> ...
> >But still same issue with irq0: clk but less now.
> >
> >IM# vmstat -i
> >interrupt                          total       rate
> >irq0: clk                       37009569       1000
> 
> >So far, you haven't provided any evidence of any "interrupt storm" or
> >how it might be related to acpi.  And 7.0 isn't stable yet.
> 
> >The default HZ is 1000 so unless you explicitly change it in your
> >kernel config, you should have 1000 clock interrupts/sec.
> 
> >-- 
> >Peter Jeremy
> 
> 
> 
> 
> Actually no more interrupt after I added these options back to my kernel while it's UP not SMP, and vmstat output has changed totally.
> 
> # To make an SMP kernel, the next two lines are needed
> options         SMP                     # Symmetric MultiProcessor Kernel
> device          apic                    # I/O APIC
> 
> IM# vmstat -i
> interrupt                          total       rate
> irq14: ata0                         4837          0
> irq23: fxp0                      2203298         86
> cpu0: timer                     50755929       1999
> Total                           52964064       2086
> 
> I even don't see irq0 in vmstat at all.
> 
> Any hints?

It looks like different timecounters are used depending on your kernel
options.  In the first case you probably used TSC or i8254 as timecounter
while in the second (where you get timer interrupts on cpu0 instead of on
irq0) you use ACPI as timecounter. 

The output of 'sysctl kern.timecounter.choice' for both cases might be
illuminating.


In any case there is still no indication of any interrupt storm.



-- 
<Insert your favourite quote here.>
Erik Trulsson
ertr1013 at student.uu.se