Soft realtime with PREEMPT-RT for NIOS II

HI Michael,

-- BTW.: what are the cons to _always_ using the realtime extensions ?

With realtime, if you have realtimer threads running always, other standard threads will never run and you will have the impress that your system is frozen if you interact with him with normal program. In fact not.

-- I understand that while the max latency is improved, the overall performance of the Kernel will be somewhat lower. Do you have numbers for that ?

One I have loaded my system with "stress -i 20 -c 20" (40 process), the max latency is about 800 µs.

-- BTW / 2.: did the lack of atomic instructions impose any problems to your work ?

For atomic operations, interrupts are disabled (it is done in the same manner with processor without atomic instructions). Just a cost in terms of latency.

Patrice.