[...] >> > >> > In the meantime, one approach is to bind all these SCHED_OTHER tasks >> > to designated housekeeping CPU(s) that don't run your main workload. >> >> One cannot bind kevent threads and other per cpu threads to another >> processor. So right now there is no way to avoid this issue. > > Yep, my approach works only for those threads that are free to migrate. > Of course, in some cases, you can avoid per-CPU threads running by pinning > interrupts, avoiding certain operations in your workload, and so on.
Speaking of threads that are not free to migrate, you might add a bit to the doc explaining that these various kernel threads that cannot migrate are also potential sources of jitter and also reasons why a CPU may exit (or not enter) full nohz mode. And thanks a ton for writing up this detailed doc. Speaking as someone trying to get full nohz working on a new arch (ARM), getting my head around all of this has been challenging, and your doc is a great help. Kevin -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
