[ECOS] Clock/interrupt latency

[Daniel Lidsten]

Hi,

I have a question regarding the clock/interrupt latency (on a MPC823e).
When i run the tm_basic test then i get a very high variation in the
measured times as you can see below.

If i look in the realtime characterization section in the user manual
then i find a variation of 3 to 5 times between maximun and average to
be normal, not as much as my measure.

---- tm_basic diag------
    4.75    3.84  158.72    0.00            Clock/interrupt latency
    5.32    3.84   12.16    0.00            Clock DSR latency
---- tm_basic ------

I tried to define diag_printf as printf and then i got the below
measurements. How come that diag_printf has that effect on my measure?

---- tm_basic printf ------
   4.75    3.84    8.96    0.00            Clock/interrupt latency
   5.20    3.52   11.84    0.00            Clock DSR latency
---- tm_basic ------

Regards, Daniel

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