Transpose-free Fast Fourier Transform for Turbulence Simulation

TL;DR

This paper introduces a transpose-free FFT algorithm that reduces communication overhead, resulting in a 15-20% speed increase over traditional FFTW in turbulence simulations.

Contribution

A novel transpose-free FFT method that enhances computational efficiency in pseudo-spectral turbulence simulations.

Findings

FFT is 15-20% faster than FFTW

Reduces interprocess communication operations

Improves efficiency of turbulence simulations

Abstract

Pseudo-spectral method is one of the most accurate techniques for simulating turbulent flows. Fast Fourier transform (FFT) is an integral part of this method. In this paper, we present a new procedure to compute FFT in which we save operations during interprocess communications by avoiding transpose of the array. As a result, our transpose-free FFT is 15\% to 20\% faster than FFTW.