Well the difference between MPOL_DEFAULT and MPOL_LOCAL may be confusing. Mention somewhere in the MPOL_LOCAL description that the policy with MPOL_DEFAULT reverts to the policy of the process and MPOL_LOCAL to try to allocate local? Note that MPOL_LOCAL also will not be local if it just happens that the local node is overallocated. This is usually confusing for newcomers. The node/zone reclaim must be activated in order to allow node local reclaim that results in a node local allocation.
