Efficient Strict-Binning Particle-in-Cell Algorithm for Multi-Core SIMD Processors

Yann A Barsamian (1, 2) , Arthur Charguéraud (1, 2) , Sever Adrian Hirstoaga (3, 4) , Michel Mehrenberger (3, 4)

1 CAMUS - Compilation pour les Architectures MUlti-coeurS
2 ICube - Laboratoire des sciences de l'ingénieur, de l'informatique et de l'imagerie
3 TONUS - TOkamaks and NUmerical Simulations
4 IRMA - Institut de Recherche Mathématique Avancée

Particle-in-Cell (PIC) codes are widely used for plasma simulations. On recent multi-core hardware, performance of these codes is often limited by memory bandwidth. We describe a multi-core PIC algorithm that achieves close-to-minimal number of memory transfers with the main memory, while at the same time exploiting SIMD instructions for numerical computations and exhibiting a high degree of OpenMP-level parallelism. Our algorithm keeps particles sorted by cell at every time step, and represents particles from a same cell using a linked list of fixed-capacity arrays, called chunks. Chunks support either sequential or atomic insertions, the latter being used to handle fast-moving particles. To validate our code, called Pic-Vert, we consider a 3d electrostatic Landau-damping simulation as well as a 2d3v transverse instability of magnetized electron holes. Performance results on a 24-core Intel Sky-lake hardware confirm the effectiveness of our algorithm, in particular its high throughput and its ability to cope with fast moving particles.

Domaines: Calcul parallèle, distribué et partagé [cs.DC]; Physique Numérique [physics.comp-ph]; Plasmas

Yann A Barsamian, Arthur Charguéraud, Sever Adrian Hirstoaga, Michel Mehrenberger. Efficient Strict-Binning Particle-in-Cell Algorithm for Multi-Core SIMD Processors. Euro-Par 2018 - 24th International European Conference on Parallel and Distributed Computing, Aug 2018, Turin, Italy. ⟨10.1007/978-3-319-96983-1_53⟩. ⟨hal-01890318⟩