[LAD] cpu spikes

Tim Goetze tim at quitte.de
Mon Jan 25 14:30:52 UTC 2016

[Fokke de Jong]
>I’m processing 32 sample-blocks at 48KHz but roughly every 0,6
>seconds I get a large spike in cpu usage. This cannot possibly be
>explained by my algorithm, because the load should be pretty stable. 
>I am measuring cpu load by getting the time with
>clock_gettime(CLOCK_MONOTONIC_RAW, timespec*) at the beginning and
>end of each callback. When converted to a percentage my cpu load
>hovers somewhere between 40 an 50% most of the time, but more or less
>every 900 callbacks (0.8 seconds there is a spike of more than 100%.

Have you checked if your per-callback CPU time measurement and that
reported by getrusage(2) are in agreement?

Cheers, Tim

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