On Wed 19-02-14 00:20:21, David Rientjes wrote: > On Wed, 19 Feb 2014, Michal Hocko wrote: > > > > I strongly suspect that the patch is correct since powerpc node distances > > > are different than the architectures you're talking about and get doubled > > > for every NUMA domain that the hardware supports. > > > > Even if the units of the distance is different on PPC should every NUMA > > machine have zone_reclaim enabled? That doesn't right to me. > > > > In my experience on powerpc it's very correct, there's typically a > significant latency in remote access and we don't have the benefit of a > SLIT that actually defines the locality between proximity domains like we > do on other architectures. Interesting. So is the PPC NUMA basically about local vs. very distant? 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? [...] Thanks! -- Michal Hocko SUSE Labs -- 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>