GPU-MPI parallelisation for QuickPIC, a three-dimensional quasi-static particle-in-cell algorithm

QuickPIC is a quasi-static PIC program for simulating plasma wakefield acceleration. It supports a hybrid parallel simulation on multiple central processing units via OpenMP and message passing interface (MPI). We now present a version of QuickPIC that runs on graphics processing units (GPU), with MPI for communication between different GPUs, based on the UCLA Parallel Partice-In-Cell framework. By rewriting relevant Fortran77 functions with CUDA C, we port the two-dimensional particle and field computations onto GPU platforms. QuickPIC-GPU supports simulation with a single GPU for up to a resolution of 1024 cubed 1024 3 1024³ and 25 particles per cell to avoid time spent on cross-processor communications, and simulation with multiple GPUs for larger problem sizes.