Comment 5 for bug 1566358

According to HugePage spec http://specs.openstack.org/openstack/nova-specs/specs/juno/approved/virt-driver-large-pages.html,

"The scheduler will be enhanced to take account of the page size setting on the flavor and pick hosts which have sufficient large pages available when scheduling the instance. Conversely if large pages are not requested, then the scheduler needs to avoid placing the instance on a host which has pre-reserved large pages. The enhancements for the scheduler will be done as part of the new filter that is implemented as part of the NUMA topology blueprint. This involves altering the logic done in that blueprint, so that instead of just looking at free memory in each NUMA node, it instead looks at the free page count for the desired page size."

So mechanism of #2 should be implemented with new filters (AggregateInstanceExtraSpecsFilter,NUMATopologyFilter). This filters are added to nova.conf when we enable HP