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Re: Hard-Realtime behaviour
Disable the caches. How long something takes to execute will depend on
what is in the cache. If the code to be executed is still in the cache
from the last time it was executied, it will execute a lot quicker
than if it has to be fetches from RAM/ROM. The same applies to the
data to be processed. So to be deterministic, you need to disable
caches.
In order to guarantee deadlines, the worst case has to be
deterministic, not the average case! In event-driven systems
everything should be fine as long as your worst case response time is
beneath your deadline, things get problematic when you use
time-discrete algorithms, of course, but in this case you are better
of using a time-driven approach, anyway.
Ciao, Fabian
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