private GpuType unify(GpuType other) {
            if (this.type == GpuType.NONE) return other;
            // XXX long-term we may need to track several GPU types, this is not good:
            return this.type;
        }
Compares storage type by cost: Remote is cheaper, and therefore before.
Any can be remote and therefore costs the same as remote.
config-provisioning/src/main/java/com/yahoo/config/provision/NodeResources.java