Re: [Xenomai-help] RT OS Selection advice for parallel processing

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

Rudolf Meijering wrote:
> Thanks a lot for everyone's input! It seems like for our application, GPU
> off-loading is not the way to go. We have redesigned our system for all
> processing to take place on the Intel i7. Total maximum processing latency
> stays 100ms, and interrupt frequency goes up to 1.5 KHz.
> 
> I have done some research on the pro's and con's of PREEMPT_RT vs Xenomai.
> As far as I can determine some of the benefits include:
> 1. Programming with Xenomai native API's are more elegant than POSIX
> real-time API’s.
> 2. Xenomai has possibly less overhead than a full preemptive kernel. The
> user interface does not require RT capabilities.
> 
> Are there any other substantial benefits worth considering? Which would you
> use?

Another factor, is that with Xenomai, the application needs a clear
separation between real-time and non real-time tasks. They do not use
the same services, they need to interact through special means. This is
a double edged sword:
- on one edge, with this clear separation, you have no doubt about which
code will be deterministic and which will not be;
- on the other edge, you end up using two APIS for interacting with two
different schedulers, which complicates things a bit.

-- 
                                                                Gilles.