[time-nuts] Cheap jitter measurements

Achim Gratz Stromeko at nexgo.de
Wed Apr 11 13:32:44 EDT 2018

Gary E. Miller writes:
> It tests the time to do two back to back clock_gettime().  Output
> looks like this:
> # ./clock_test 
> samples 101, delay 10000000 ns
> min 67 ns, max 302 ns, mean 176 ns, median 197 ns, StdDev 52 ns
> You run it a few times and you will see the granularity in the
> measurements is 10's of ns, or more, depending on your CPU.

…and it has to be 52ns since the timer that's used by the kernel on the
newer rasPi runs off the 19.2MHz clock.

+<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+

SD adaptations for Waldorf Q V3.00R3 and Q+ V3.54R2:

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