VPIC 2.0: Next Generation Particle-in-Cell Simulations

TL;DR

VPIC 2.0 advances particle-in-cell plasma simulations by optimizing for exascale platforms, leveraging Kokkos for portability, and demonstrating high performance across diverse supercomputers.

Contribution

This work introduces VPIC 2.0 with exascale optimizations and portability enhancements, enabling efficient plasma simulations on modern heterogeneous hardware.

Findings

Achieved high performance on nine pre-exascale hardware platforms.

Demonstrated weak scaling on three top supercomputers.

Compared low-level system performance across four hardware vendors.

Abstract

VPIC is a general purpose Particle-in-Cell simulation code for modeling plasma phenomena such as magnetic reconnection, fusion, solar weather, and laser-plasma interaction in three dimensions using large numbers of particles. VPIC's capacity in both fidelity and scale makes it particularly well-suited for plasma research on pre-exascale and exascale platforms. In this paper we demonstrate the unique challenges involved in preparing the VPIC code for operation at exascale, outlining important optimizations to make VPIC efficient on accelerators. Specifically, we show the work undertaken in adapting VPIC to exploit the portability-enabling framework Kokkos and highlight the enhancements to VPIC's modeling capabilities to achieve performance at exascale. We assess the achieved performance-portability trade-off through a suite of studies on nine different varieties of modern pre-exascale hardware. Our performance-portability study includes weak-scaling runs on three of the top ten TOP500 supercomputers, as well as a comparison of low-level system performance of hardware from four different vendors.