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Re: Thread activation disturbed by lower priority threads]
Hi,
thanks you definitely pointed me into the right direction. The problem
is located with the mutexes. I removed all mutexes in questions and set
my timing measurement points directly after the semaphore that is in
charge of activating my threads.After making more measurements and
playing a little bit around I found it that when I set the priority
inversion protocol to none (using cyg_mutex_set_protocol). The timing is
as expected. So I thought it could be that before I was using priority
ceiling which would be an explanation for the delay as every time a
mutex is gathered the thread will get priorty 0. So I changed to
priority inheritance. This from my point of view should do the job as I
like to have it done.
But when using priority inheritance I get the same bad timing as in the
beginning.
And as longer I think I don't know why the tread activation of the
highest priority thread is prolonged by threads holding a mutex with
priority inheritance where each of the treads that my also get this
mutex has a lower priority. So I'm completly confuesed. Any Ideas what
could be the problem or what I could do?
For my current tests no priority inversion protocol is just fine, but
for further more complected tests I think i will need something like
priority inheritance so it would be nice to have it.
Thanks,
Alois
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