Re: rt20 scheduling latency testcase and failure data

From: Sébastien Dugué
Date: Thu May 18 2006 - 04:39:37 EST


On Mon, 2006-05-15 at 18:30 -0700, Darren Hart wrote:
> Following Ingo's example I have included the modified test case (please see
> the original mail for librt.h) that starts the trace before each sleep and
> disables it after we wake up. If we have missed a period, we print the
> trace.

Your test program fails (at least on my box) as the overhead of
starting and stopping the trace in the 5 ms period is just too high.

By moving the latency_trace_start() at the start of the thread
function and latency_trace_stop() at the end, everything runs fine.
I did not have any period missed even under heavy load.


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