Re: [patch] voluntary-preempt-2.6.8-rc2-L2, preemptable hardirqs

Thomas Charbonnel
2004-07-28T15:11:01Z

> * Thomas Charbonnel <thomas@undata.org> wrote:
>
> > The other source of xrun was seen during the disk write tests, once
> > the memory runs out (spikes up to 14 ms, but more generally 6 ms)
>
> which particular filesystem and disk driver are you using? (ext3/IDE?)
> The 'disk write tests' are those of latencytest-0.5.4?
>
> Ingo

It's an IDE reiserfs disk.
Those are indeed the disk write tests from latencytest-0.5.4
My mistake about the spikes, they are more 3 ms than 6.
You can see the results here :
http://www.undata.org/~thomas/latencytest-0.5.4/rtc_freq_2048/
http://www.undata.org/~thomas/latencytest-0.5.4/rtc_freq_4096/
http://www.undata.org/~thomas/latencytest-0.5.4/rtc_freq_8192/

The traces always look the same :

T=29.6014 diff=14.4758
rtc_interrupt (+bd)
handle_IRQ_event (+50)
do_hardirq (+bc)
irqd (+ac)
kthread (+aa)
irqd (+0)
kthread (+0)
kernel_thread_helper (+5)

Thomas