Re: rt20 scheduling latency testcase and failure data

[Sébastien Dugué]

  Darren,

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.

  Sébastien.

  

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