GPU Computing Gems Emerald Edition

Chapter 39. Large-Scale Fast Fourier Transform

Yifeng Chen, Xiang Cui and Hong Mei

Bandwidth-intensive tasks such as large-scale fast Fourier transfers (FFTs) without data locality are hard to accelerate on GPU clusters because the bottleneck often lies with the PCI bus or the communication network. Optimizing FFT for a single-GPU device will not improve the overall performance. This chapter shows how to achieve substantial speedups for these tasks. Three GPU-related factors contribute to better performance: first, the use of GPU devices improves the sustained memory bandwidth for processing large-size data; second, GPU device memory allows larger subtasks to be processed in whole and hence reduces repeated data transfers between memory and processors; ...