Category II: Ookami: A High-Productivity Path to Frontiers of Scientific Discovery Enabled by Exascale Systems Technologies

The State University of New York proposes to procure and operate for at least four years the first computer outside of Japan with the A64fx processor developed by Fujitsu for the Japanese path to exascale computing (i.e., computers capable of 10^18 operations per second). The ARM-based, multi-core, 512-bit SIMD-vector processor with ultrahigh-bandwidth memory promises to retain familiar and successful programming models while achieving very high performance for a wide range of applications including simulation and big data. The testbed significantly extends current NSF-sponsored HPC technologies and will enable the community to evaluate and demonstrate the potential of this technology for deployment in multiple settings. Through integration with NSF's Extreme Science and Engineering Discovery Environment (XSEDE), the system will be widely accessible and fully leverages existing cyber infrastructure including the XDMoD monitoring system. What does this mean for science? Compared with the best CPUs anticipated during the deployment period, A64fx offers 2-4x better performance on memory-intensive applications such as sparse-matrix solvers found in many engineering and physics codes. For nearly all other applications, performance is also better or competitive. This transformational performance should be available nearly out of the box, with additional performance possible from tuning. To the scientist or engineer this means faster time to solution with significantly less programmer effort. The target class of applications to be enabled are memory-bandwidth intensive with 32GB/node memory, with significant gains anticipated for many other applications. Analysis of XSEDE workload shows 86% of all jobs (85% cycles) will fit within the available memory per node and that the majority of jobs are memory-bandwidth intensive. Finally, we have concrete plans to substantially broaden participation in science and engineering research by partnering with external organizations at the institutional, regional, and national levels. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.