Hierarchical Communication Optimization for FFT
DescriptionFast Fourier Transforms (FFT) are used to solve various scientific and engineering problems. For example, computational fluid dynamics (CFD) simulations employ a pseudo-spectral method to solve flow simulations using Fast Fourier transforms (FFT). FFT requires global communications among all parallel processes; this often increases communication times. We present FFTOpt, a communication optimization library that leverages hierarchical communications within a compute node and across nodes of a large-scale system. This is a generic library that may optimize any code or application that uses MPI_Alltoall and MPI_Sendrecv without any dependency on the system or application. FFTOpt also uses topology information and runtime details about node allocation to aggregate at node and switch levels to reduce communication times. We tested FFTOpt in our department cluster and PARAM Sanganak supercomputer of IIT Kanpur using the FFTW, FFTK and P3DFFT libraries. FFTOpt reduces communication time by up to 63%.
TimeFriday, 18 November 202210:30am - 10:50am CST
Parallel Programming Languages and Models
Parallel Programming Systems
Resource Management and Scheduling