Abstract

Today 80 years old, the CEA (Commissariat à l’Énergie Atomique et aux Énergies Alternatives) is France’s public research organisation specialising in nuclear energy and renewable energies, nuclear dissuasion, fundamental research and technological research. These activities hinge on numerical simulation, namely with production codes in fluid dynamics, structural mechanics, atomistics and molecular dynamics just to mention a few. With the advent of exascale computing era, mostly achieved with heterogeneous systems (CPU and GPU), software developpers have to adapt to this new paradigm shift to obtain good performance when required. CEA is a major player in the High-Performance Computing (HPC) ecosystem in France, Europe and international level and will host the second European exascale system, Alice Recoque. In this talk, we will highlight some of our applicative uses of HPC for energy and why we chose Kokkos, a performance portability layer to tackle such exascale systems. We will first introduce Kokkos through an overview of the CEA project and then, give some examples in our applications.