OpenFFT - An Open Source Parallel Package for 3-D FFTs

Introduction Download Features Manual Publications Acknowledgements Feedback

Introduction

OpenFFT is an open source parallel package for computing multi-dimensional Fast Fourier Transforms (3-D and 4-D FFTs) of both real and complex numbers of arbitrary input size. It originates from OpenMX (Open source package for Material eXplorer). OpenFFT adopts a communication-optimal domain decomposition method that is adaptive and capable of localizing data when transposing from one dimension to another for reducing the total volume of communication. It is written in C and MPI, with support for Fortran through the Fortran interface, and employs FFTW3 for computing 1-D FFTs.

OpenFFT is developed by Truong Vinh Truong Duy and Taisuke Ozaki at the University of Tokyo.

Download

OpenFFT version 1.2 is the latest vesion of OpenFFT, and is downloadable from here.

RELEASE NOTES:

OpenFFT version 1.2 (March 31, 2015)

Download: openfft1.2.tar.gz. Manual: manual1.2.html (HTML), OpenFFT1.2_Guide.pdf (PDF).
Addition of parallel 4-D FFTs with openfft_init_c2c_4d() and openfft_exec_c2c_4d() for initialization and execution, respectively.
Addition of hybrid MPI/OpenMP execution.

OpenFFT version 1.1 (November 11, 2014)

Download: openfft1.1.tar.gz. Manual: manual1.1.html (HTML), OpenFFT1.1_Guide.pdf (PDF).
The c2c interface is changed from openfft_initialize() and openfft_execute() to openfft_init_c2c_3d() and openfft_exec_c2c_3d() for initialization and execution, respectively.
Addition of the r2c interface comprised of openfft_init_r2c_3d() and openfft_exec_r2c_3d().
Addition of the tuning of communication to the c2c and r2c interfaces.

OpenFFT version 1.0 (August 23, 2013)

Download: openfft1.0.tar.gz. Manual: manual1.0.html.

Features

Domain decomposition method: OpenFFT adopts a decomposition method that is capable of localizing data when transposing from one dimension to another for reducing the total volume of communication. Also, the decomposition is adaptive, and can automatically switch between 1-D, 2-D, and 3-D (for 4-D FFTs) depending on the number of processes and data size. Please refer to the publications for detail.
Support for fast parallel complex-to-complex and real-to-complex transforms of 3-D FFTs and 4-D FFTs with arbitrary input size.
Tuning of communication with an auto-tuning feature.
Support for hybrid MPI/OpenMP execution.
Portable, tested on various general-purpose Linux clusters and popular supercomputers, including Cray XC30, SGI Altix UV1000, SGI InfiniBand cluster, FX10, and the K computer.
Written in C and MPI, with support for Fortran through the Fortran interface.
Open source package, released under the GNU General Public License (GPL).

Manual

The manual of the latest version: manual1.2.html (HTML), OpenFFT1.2_Guide.pdf (PDF).

Publications

[1] T.V.T. Duy and T. Ozaki, "A decomposition method with minimum communication amount for parallelization of multi-dimensional FFTs", Computer Physics Communications, Vol. 185, Issue 1, pp. 153-164, 2014. DOI: 10.1016/j.cpc.2013.08.028

[2] T.V.T. Duy and T. Ozaki, "A three-dimensional domain decomposition method for large-scale DFT electronic structure calculations", Computer Physics Communications, Vol. 185, Issue 3, pp. 777-789, 2014. DOI: 10.1016/j.cpc.2013.11.008

[3] Best Research Poster Award for "OpenFFT: An Open-Source Package for 3-D FFTs with Minimal Volume of Communication", the 29th International Supercomputing Conference (ISC'14), 2014.

Acknowledgements

This package has its origins in OpenMX (Open source package for Material eXplorer), and has been funded by CMSI (Computational Materials Science Initiative) of the HPCI Strategic Program (SPIRE) of the Ministry of Education, Culture, Sports, Science and Technology of Japan. We are thankful to Japan Advanced Institute of Science and Technology (JAIST) for the computational resources. We also thank Prof. Katsumi Hagita of National Defense Academy of Japan for helpful discussions and contribution to the r2c 3-D interface.

Feedback

Please feel free to drop us a line at duytvt@issp.u-tokyo.ac.jp (Truong Vinh Truong Duy) or t-ozaki@issp.u-tokyo.ac.jp (Taisuke Ozaki) for questions, comments, suggestions, and bug reports.

Last updated: March 31, 2015.