On Tue, Apr 08, 2014 at 03:56:49PM -0400, Josh Berkus wrote: > On 04/08/2014 03:53 PM, Robert Haas wrote: > > In an ideal world, the kernel would put the hottest pages on the local > > node and the less-hot pages on remote nodes, moving pages around as > > the workload shifts. In practice, that's probably pretty hard. > > Fortunately, it's not nearly as important as making sure we don't > > unnecessarily hit the disk, which is infinitely slower than any memory > > bank. > > Even if the kernel could do this, we would *still* have to disable it > for PostgreSQL, since our double-buffering makes our pages look "cold" > to the kernel ... as discussed. > If it's the shared mapping that is being used then automatic NUMA balancing should migrate those pages to a node local to the CPU accessing it but how well it works will partially depend on how much those accesses move around. It's independent of the zone_reclaim_mode issue. -- 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>