Special Session 115: Computational Techniques Using Fast Fourier Transformation (FFT) for Partial Differential Equations

Implementation of Parallel 3-D Real FFT with 2-D Decomposition on Manycore Clusters

Daisuke Takahashi
University of Tsukuba
Japan
Co-Author(s):    Daisuke Takahashi
Abstract:
In this talk, we propose an implementation of parallel three-dimensional real fast Fourier transforms (FFTs) with two-dimensional decomposition on manycore clusters. The proposed parallel three-dimensional FFT algorithm is based on the conjugate symmetry property for the discrete Fourier transform (DFT) and the multicolumn FFT algorithm. We show that a two-dimensional decomposition effectively improves performance by reducing the communication time for larger numbers of MPI processes. We also present a computation-communication overlap method that introduces a communication thread with OpenMP. Performance results of three-dimensional real FFTs on manycore clusters are reported.