Unprecedented Scalability and Performance of the New NNSA Tri-Lab Linux Capacity Cluster 2

As one of the largest users of supercomputing resources in the world, capacity computing is a critical component in the NNSA's (National Nuclear Security Administration) Advanced Simulation and Computing (ASC) program. The latest acquisitions in this program - named the Tri-Lab Linux Capacity Cluster 2 (TLCC2) machines - have recently been installed at the three NNSA laboratories: Sandia National Laboratories, Los Alamos National Laboratories and Lawrence Livermore National Laboratories. In this paper we investigate performance on Chama, Sandia's 1232 node cluster, with dual socket Intel Xeon Sandy Bridge processors connected using Qlogic QDR InfiniBand. Production applications benchmarked on Chama reveal significant improvements in the time to solution and scalability when compared against our earlier generation capacity clusters and a PetaFlops class capability machine.