Evaluation of the Communication Motif for a Distributed Eigensolver using the SST Network Simulation Tool

A new motif that corresponds to the communication operations of the distributed LOBPCG eigensolver used in the Many-Fermion Dynamics-nuclear, or MFDn, code is constructed. The impact of communication strategy and process placement are evaluated on current and future architectures using the SST network simulation tool. Simulation of the communication motif is validated against production runs on the Cori system at NERSC. We identify the strengths and shortcomings of SST in doing so.