Parallel 3-dim fast Fourier transforms with load balancing of the plane waves

TL;DR

This paper introduces a new parallel 3D FFT algorithm with load balancing for plane wave methods, significantly improving scalability in first-principles materials science computations.

Contribution

A novel partitioning algorithm for 3D FFT grids that balances load and reduces communication overhead, enhancing scalability of plane wave calculations.

Findings

Scales to more nodes in parallel computations

Reduces communication overhead

Improves load balancing in 3D FFTs

Abstract

The plane wave method is most widely used for solving the Kohn-Sham equations in first-principles materials science computations. In this procedure, the three-dimensional (3-dim) trial wave functions' fast Fourier transform (FFT) is a regular operation and one of the most demanding algorithms in terms of the scalability on a parallel machine. We propose a new partitioning algorithm for the 3-dim FFT grid to accomplish the trade-off between the communication overhead and load balancing of the plane waves. It is shown by qualitative analysis and numerical results that our approach could scale the plane wave first-principles calculations up to more nodes.