On Thu, Jul 10, 2014 at 08:14:19AM -0400, Johannes Weiner wrote: > On Wed, Jul 09, 2014 at 09:13:07AM +0100, Mel Gorman wrote: > > The purpose of numa_zonelist_order=zone is to preserve lower zones > > for use with 32-bit devices. If locality is preferred then the > > numa_zonelist_order=node policy should be used. Unfortunately, the fair > > zone allocation policy overrides this by skipping zones on remote nodes > > until the lower one is found. While this makes sense from a page aging > > and performance perspective, it breaks the expected zonelist policy. This > > patch restores the expected behaviour for zone-list ordering. > > > > Signed-off-by: Mel Gorman <mgorman@xxxxxxx> > > 32-bit NUMA? :-) I'm tempted to just say "it can go on fire" but realistically speaking they should be configured to use node ordering. I was very tempted to always force node ordering but I didn't have good data on how often lowmem allocations are required on NUMA machines. > Anyway, this change also cuts down the fair pass > overhead on bigger NUMA machines, so I'm all for it. > > Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx> Thanks for the reviews! -- Mel Gorman 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>