Re: how to measure scheduler latency on powerpc? realfeel doesn't work due to /dev/rtc issues

Chris Friesen (cfriesen@nortelnetworks.com)
Fri, 09 May 2003 02:53:00 -0400

William Lee Irwin III wrote:

> I don't understand why you're obsessed with interrupts. Just run your
> load and spray the scheduler latency stats out /proc/

I'm obsessed with interrupts because it gives me a higher sampling rate.

I could set up and itimer for a recurring 10ms timeout and see how much extra I
waited, but then I can only get 100 samples/sec.

With /dev/rtc (on intel) you can get 20x more samples in the same amount of time.

Chris

-- 
Chris Friesen                    | MailStop: 043/33/F10
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