RTAI, Xenomai....

Hello...

I read somewhere that linuxcnc with Xenomai (instead RTAI) should work better. Is that true? Is there some benchmarks?!?

Thanks.

In general RTAI has the best latency figures, followed by Xenomai and then Preemt-RT

If you are generating step pulses in software on a X86 processor
( a parallel port system for example), RTAI is probably still the best choice.
Some disadvantages of RTAI are that its support of newer Linux kernels lags and
there is no support for modern ARM systems.

Xenomai is used by Machinekit running on the BBB, but since the BBB has an attached
real time processor for actual step pulse generation, Xenomai's poorer latency is not significant

Preemt-RT has the worst latency figures of the three, but is fine for servo thread only systems
(systems with external step generation and perhaps encoder counting, PWM generation etc).
and like Xenomai, Preemt-RT is available for X86 and ARM and supports up-to date linux kernels.

Thanks for answers...

So on PC side RTAI seems best candidate (I need CNC not latest OS).
Now I just need to decide to use BBB or PC to control minilathe. Perheaps the BBB can drive lathe (2 steppers) and axis interface...