On Wed, Jun 04, 2014 at 04:09:42PM -0400, Rik van Riel wrote: > The first thing task_numa_migrate does is check to see if there is > CPU capacity available on the preferred node, in order to move the > task there. > > However, if the preferred node is all busy, we would skip considering > that node for tasks swaps in the subsequent loop. This prevents NUMA > convergence of tasks on busy systems. > > However, swapping locations with a task on our preferred nid, when > the preferred nid is busy, is perfectly fine. > > The fix is to also look for a CPU on our preferred nid when it is > totally busy. > > This changes "perf bench numa mem -p 4 -t 20 -m -0 -P 1000" from > not converging in 15 minutes on my 4 node system, to converging in > 10-20 seconds. > > Signed-off-by: Rik van Riel <[email protected]>
Indeed so. Thanks Rik! -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
