Kokkos implementation of an Ewald Coulomb solver and analysis of performance portability

We have implemented the computation of Coulomb interactions in particle sys-tems using the performance portable C++ framework Kokkos. For the com-putation of the electrostatic interactions in particle systems we used an Ewaldsummation. This implementation we consider as a basis for a performanceportability study. As target architectures we used Intel CPUs, including In-tel Xeon Phi, as well as Nvidia GPUs. To provide a measure for performanceportability we compute the number of needed operations and required cycles,i.e. runtime, and compare these with the measured runtime. Results indicate asimilar quality of performance portability on all investigated architectures