[Xenomai] questions: real-time scheduler

[Xenomai] questions: real-time scheduler

[ali hagigat]

I have some questions as follows:

1) If i have one real time task and that task is big and does not
finish soon or it has an infinite loop at the end like:
here:  goto here;

Will other non real-time tasks be scheduled? or a real time task will
run to completion.

2) If I have an infinite loop like the above at the end of a real time task:
here:  goto here;

Does the scheduler recognizes this situation to not to schedule this
task, because it does nothing virtually or it assigns a time slot to
that task?

3) What factors effect the length of the time slot assigned to each
real time task? I mean how long CPU continues to stay inside the code
of a real time task?

4) I have a multi-core CPU, can i assign one CPU to a specific task?

5) I want a specific code to be executed (and completed) like every 1
ms (or n ms) on a x86 PC computer. Is it possible with Xenomai?

6) is there any document to explain the architecture of the Xenomai
real time scheduler?

Regards

Re: [Xenomai] questions: real-time scheduler

[Gilles Chanteperdrix]

On 07/08/2012 02:13 PM, ali hagigat wrote:
> I have some questions as follows:
> 
> 1) If i have one real time task and that task is big and does not
> finish soon or it has an infinite loop at the end like:
> here:  goto here;
> 
> Will other non real-time tasks be scheduled? or a real time task will
> run to completion.
> 
> 2) If I have an infinite loop like the above at the end of a real time task:
> here:  goto here;
> 
> Does the scheduler recognizes this situation to not to schedule this
> task, because it does nothing virtually or it assigns a time slot to
> that task?
> 
> 3) What factors effect the length of the time slot assigned to each
> real time task? I mean how long CPU continues to stay inside the code
> of a real time task?
> 
> 4) I have a multi-core CPU, can i assign one CPU to a specific task?
> 
> 5) I want a specific code to be executed (and completed) like every 1
> ms (or n ms) on a x86 PC computer. Is it possible with Xenomai?
> 
> 6) is there any document to explain the architecture of the Xenomai
> real time scheduler?

What about reading xenomai documentation, see what services are
available, and writing a few test programs to understand how thet work?

xenomai scheduler is mainly a fixed priority pre-emptive scheduling:
http://en.wikipedia.org/wiki/Fixed_priority_pre-emptive_scheduling

-- 
                                                                Gilles.