Fedora style version of RedHat RHEL MRG? 
jacquesm: I haven't but I really wished that the realtime patches would be made a standard part of the kernel. Lots of code could take advantage of that.MRG supports MPI, the de-facto message passing interface for clusters, that alone makes it worth looking at.One step closer to QnX...To have the CONFIG_PREEMPT_RT patch in stock kernel would be very nice. A real-time kernel is not just for people controlling machinery.If you are going to spend time on this will you please do a write-up of your experiences ?