Toward an OpenSHMEM Teams Extension to Enable Topology-Aware Parallel Programming

The quest to reach exascale performance and beyond, requires holistic, system wide optimizations, including techniques to achieve more effective mappings of applications to the evolving system topology. Presently, the OpenSHMEM [3] standardization group is defining a new Processing Element (PE) teams API. Teams have conventionally been used in, e.g. MPI communicators [2], to define communication groups. In this work, we consider expanding upon this usage model by defining a teams interface that can be used to expose detailed system topology information to application developers. In addition to supporting conventional communication groups, the proposed teams API can be used to dynamically expose evolving network topology as well as heterogeneous node architecture and characteristics.