Efficient parallelization for 3D-3V sparse grid Particle-In-Cell: shared memory systems architectures

A. Particle-In-Cell (PIC) schemes are ones of the most broadly used numerical methods in kinetic simulation of plasmas. The contribution of the present paper is dedicated to the introduction of parallelization strategies specific to shared memory architectures tailored for Particle-In-Cell methods implementing sparse grid reconstructions. These strategies operate the different parallelisms genuine to Sparse-PIC methods to obtain speed-up exceeding 100 on 128 cores. On top of that substantial gains are introduced for sequential as well as parallel implementations thanks to the hierarchization procedure. It consists in decomposing the information carried by sparse grids onto hierarchical basis functions, entailing a significantly reduced number of operations