On Wed, 19 Feb 2014, Michal Hocko wrote: > Interesting. So is the PPC NUMA basically about local vs. very distant? The point is that it's impossible to tell how distant they are from one NUMA domain to the next NUMA domain. > Should REMOTE_DISTANCE reflect that as well? Or can we have > distance < REMOTE_DISTANCE and it would still make sense to have > zone_reclaim enabled? > Ppc doesn't want to allocate in a different NUMA domain unless required, the latency of a remote access is too high. Everything that isn't in the same domain has a distance >10 and is setup as 2^(domain hops) * 10. We don't have the ability like with a SLIT to define remote nodes to have local latency vs remote or costly latency so the safe setting is a RECLAIM_DISTANCE of 10. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>