Abstract of GBSHYB-2 Project

We propose to complete the necessary steps to port the GBS code, used to simulate plasma turbulence in the tokamak SOL, to hybrid architecture computers. In fact, cluster systems built with general-purpose processors are superseded today by platforms built around hybrid architectures, with nodes constituted by processors based on CPU cores and many-core accelerated devices (MIC) or graphical processing units (GPU). By being able to exploit the capabilities of these computers, we expect to be able to significantly enhance the computational capabilities of GBS, which is currently being executed on standard platforms. In particular, extending the previous project GBSHYB, where a hybrid parallel programming mode (OpenMP+MPI) was implemented in a multigrid solver used by GBS and initial steps were undertaken to include OpenACC directives, we propose to include the OpenACC directives to port first the multigrid solver and then the whole GBS code to clusters based on hybrid architecture (MIC and GPU graphic accelerators). GBS will then be tested on the supercomputers based on hybrid architectures. By being able to exploit these computers, we expect GBS to perform full size simulations of SOL plasma turbulence in JET and ITER that are presently out of reach.