Michael Ost wrote: > Have you ever seen "migration" or "watchdog" hold the CPU for any length of > time?
This shouldn't happen. > I was curious about "migration" since > > /proc/sys/kernel/sched_migration_cost = 500000 When migrating threads to another CPU (core), there is no big delay because real-time threads have well-defined scheduling behaviour and either interrupt the running thread immediately or go into the runnable queue like other threads that already are on that CPU. The reason that the cost is set so high is that the new thread will run slower because it has to pull over its data from the other cache. I guess I can rule out SMIs because those should happen even when there is one thread per core. How big are the latencies you're seeing? They are not from being interrupted by another RR thread at the same priority (see "man sched_rr_get_interval")? Regards, Clemens _______________________________________________ Linux-audio-dev mailing list [email protected] http://lists.linuxaudio.org/listinfo/linux-audio-dev
