On Thu, Jun 25, 2015 at 09:48:55PM +0100, Mel Gorman wrote: > On Wed, Jun 24, 2015 at 05:50:28PM -0500, Nathan Zimmer wrote: > > My apologies for taking so long to get back to this. > > > > I think I did locate two potential sources of slowdown. > > One is the set_cpus_allowed_ptr as I have noted previously. > > However I only notice that on the very largest boxes. > > I did cobble together a patch that seems to help. > > > > If you are using kthread_create_on_node(), is it even necessary to call > set_cpus_allowed_ptr() at all? >
Yup kthread_create_on_node unconditionanly calls set_cpus_allowed_ptr(task, cpu_all_mask); It does it to avoid inherting kthreadd's properties. Not being familiar with scheduling code I assumed I missed something. However it sounds like it should respect the choice. -- 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/
