Re: Rescheduling interrupts

From: Ingo Molnar
Date: Tue Jan 22 2008 - 11:06:29 EST



* S.ÃaÄlar Onur <caglar@xxxxxxxxxxxxx> wrote:

> > My theory is that for whatever reason we get "repeat" IPIs: multiple
> > reschedule IPIs although the other CPU only initiated one.
>
> Ok, please see http://cekirdek.pardus.org.tr/~caglar/dmesg.3rd :)

hm, the IPI sending and receiving is nicely paired up:

[ 625.795008] IPI (@smp_reschedule_interrupt) from task swapper:0 on CPU#1:
[ 625.795223] IPI (@native_smp_send_reschedule) from task amarokapp:2882 on CPU#1:

amarokapp does wake up threads every 20 microseconds - that could
explain it. It's probably Xorg running on one core, amarokapp on the
other core. That's already 100 reschedules/sec.

Ingo
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