Hi, 

as I got no response to me questions (see below) I may have to add a few things 
for clarification.

First of all I'm running an an AT91M5580A processor (thy phytec board). I 
changed the ecos settings so that the timer tick is now 1ms. The reason for 
this is that I need such a small tick for my application. Does this anyhow 
influence the scheduling algorithm. Are there settings that need to be adjusted 
appart from denominator, nominator and timesclice value?

I did more measurements and found out that the timer DSR is really stable. even 
more stable than on some other systems (non ecos) I'm using. The problem is 
that the time between posting on the semaphore (the thread is waiting on) until 
the thread starts executing  is varying largly. It seems that it is prolonged 
by other execution elements. And this even when the thread under question is 
the thread with the highest priority.

would be great if this clearifies my problem a little bit more.

Thanks,
Alois

Hi,

In a larger project I have a problem when doing a timed activation of threads.

In the timer alarm handler I check if any thread is ready for activation and 
post on a semaphore the thread is waiting for.

This works fine when I have only one or two such timed threads the activation 
jitter of the thread (i.e. the jitter when the threads starts its execution) is 
ok. But when I add more threads this jitter grows tremendously. Each thread has 
an own priority. And event the thread with with the highest priority (in my 
case 2) has this large jitter (more than half of the cycle time).

Is there a way to improve the behavior of the activation. Do I the timed 
activation the wrong way. Can I improve the timing behavior of the scheduler 
through the real-time clock settings.

By the way I use the multilevel scheduler.

Thanks,
Alois



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