I've been experimenting with the high-resolution timer subsystem on the
x86 platform (specifically, P4 2.8 GHz) running Linux 2.6.16.28. (LAPIC
and IOAPIC turned on, pre-emptible kernel, HZ=250)
I wrote a small app to create a POSIX timer (timer_create(),
timer_settime(), etc) that fires with a given period. The scheduling
policy is set to SCHED_RR. After some time, the process writes the
distribution of "elapsed time between signals" to a file, and exits. I
then post-process this file to output average time between signals,
standard deviation, occurences +/- 5 µs and occurences +/- 10 µs.
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