The International Conference for High Performance Computing, Networking, Storage, and Analysis
The International Conference for High Performance Computing, Networking, Storage, and Analysis
Workshop:P3HPC: 2021 International Workshop on Performance, Portability, and Productivity in HPC
Authors: Yuuichi Asahi (Japan Atomic Energy Agency) and Guillaume Latu, Julien Bigot, and Virginie Grandgirard (French Alternative Energies and Atomic Energy Commission (CEA))
Abstract: This paper presents optimization strategies applied on a kinetic plasma simulation code that makes use of OpenACC/OpenMP directives and Kokkos performance portable framework to run across multiple CPUs and GPUs. We evaluate the impacts of optimizations on multiple hardware platforms: Intel Xeon Skylake, Fujitsu Arm A64FX, and Nvidia Tesla P100 and V100. After the optimizations, the OpenACC/OpenMP version achieved speedups of 1.07 to 1.39. The Kokkos version in turn achieved speedups of 1.00 to 1.33. Since the impact of optimizations under multiple combinations of kernels, devices and parallel implementations is demonstrated, this paper provides a widely available approach to accelerate codes keeping the performance portability. To achieve a good performance on both CPUs and GPUs, Kokkos could be a reasonable choice which offers more flexibility to manage multiple data and loop structures with a single codebase.