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The > low priority threads are interact with the time critical ones, using > semaphores for data synchronization. The scheduling policy of these > time critical threads are SCHED_RR to be Xenomai threads. The others > are SCHED_OTHER so (in my understanding) handled by the Linux > scheduler. > > Is this the right solution, or should I make all threads to be Xenomai threads? > > What is the best practice to get the lowest latency for the time > critical threads? To get some load off of the Xenomai scheduler (by > removing the not time critical threads to Linux scheduler) or keep all > threads as Xenomai threads? The best latency you generally get via - having RT threads on isolated cores, doing as little other stuff as possible there - using wait-free algorithms for the RT side to exchange data with the non-RT side Jan -- Siemens AG, Technology Competence Center Embedded Linux