Messages in this thread | | | Date | Thu, 31 Mar 2005 13:35:27 +0200 | From | Ingo Molnar <> | Subject | Re: 2.6.11, IDE: Strange scheduling behaviour: high-pri RT process not scheduled? |
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* kus Kusche Klaus <kus@keba.com> wrote:
> I've written a small test program which enables periodic RTC > interrupts at 8192 Hz and then goes into a loop reading /dev/rtc and > collecting timing statistics (using the rdtscl macro).
getting /dev/rtc handling right for latency measurement is ... tricky. The method i'm using under PREEMPT_RT is:
chrt -f 84 -p `pidof 'IRQ 0'` chrt -f 95 -p `pidof 'IRQ 8'` ./rtc_wakeup -f 1024 -t 100000
you can get rtc_wakeup from:
http://www.affenbande.org/~tapas/wiki/index.php?rtc_wakeup
written by Florian Schmidt.
do you see high latencies even with rtc_wakeup?
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