30% Faster Bitonic Sort on CUDA: Leveraging Warp Shuffle
2025-05-06
This blog post details a CUDA implementation of the Bitonic sorting algorithm, achieving a 30% performance boost by cleverly using the `__shfl_sync` instruction. The author explains the principles of Bitonic sort, SIMD programming, and CUDA implementation specifics. The key optimization lies in replacing traditional shared memory communication with `__shfl_sync`, eliminating synchronization overhead and significantly improving efficiency. The post also hints at the potential for using this accelerated 32-element sort to speed up sorting of larger sequences, promising a follow-up on optimizing 32-way merging.