Various approaches are described for allocating memory objects in a non-uniform memory access (NUMA) system. In one embodiment, at least one instance of a data structure of a first type is established to include a plurality of locality definitions. Each instance of the first type data structure has an associated set of program-configurable attributes that are used in controlling allocation of memory objects via the instance. Each locality definition is selectable via a locality identifier and designates a memory subsystem in the NUMA system. In response to a request from a processor in the NUMA system for allocation of memory objects via an instance of the first type data structure and specifying a locality identifier, memory objects are allocated to the requesting processor from the memory subsystem designated by the locality definition as referenced by the locality identifier.