[ECOS] Need help for tm_basic tests result interpretation

[Guilly A]

Hi,
I ran the tm_basic test on my ARM9 Excalibur dev board (20 Mhz) to evaluate 
task switching latency.
I got those results :
                                 Confidence
     Ave     Min     Max     Var  Ave  Min  Function
  ======  ======  ======  ====== ========== ========
7666.09    0.00 9739.60 2525.44   75%    8%  Create thread
3120.45 1566.91 6529.98 2069.60   66%   66%  Yield thread [all suspended]
2378.00 1213.21 6114.28 1743.56   75%   75%  Suspend [suspended] thread
2541.47 1299.91 6409.08 1859.62   75%   75%  Resume thread
3267.81 1642.51 6784.58 2162.32   66%   66%  Set priority
  115.81  114.80  117.40    0.56   66%   33%  Get priority
8492.99 4557.72 9684.50 1311.31   83%   16%  Kill [suspended] thread
3123.24 1568.71 6527.68 2071.16   66%   66%  Yield [no other] thread
3492.77 1871.41 7374.19 2158.86   66%   66%  Resume [suspended low prio] 
thread
2524.19 1286.81 6737.48 1854.38   75%   75%  Resume [runnable low prio] 
thread
3143.01 1585.51 6678.78 2070.60   66%   66%  Suspend [runnable] thread
3124.06 1569.71 6543.18 2070.63   66%   66%  Yield [only low prio] thread
2383.53 1217.31 6110.78 1747.52   75%   75%  Suspend [runnable->not 
runnable]
7733.68 4604.72 9704.50 2020.48   66%   33%  Kill [runnable] thread
5535.64 3034.92 8483.69 2494.61   41%   50%  Destroy [dead] thread
3379.34 1591.41 7137.59 2225.98   66%   66%  Destroy [runnable] thread
1324.72  464.40 5441.68  873.83   83%   83%  Resume [high priority] thread
  348.40 2848.41 7894.09    0.00    0%    0%  Thread switch

This last line gives me troubles. It seems that I can't rely on this 
numbers, I don't understand how
we can have such average value below the minimum value. And I found it very 
slow to take more t han a millisecond to switch from a task to another. I'm 
I wrong ?

How mutch time should it take on such a target ?

Regards...

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