Editorial illustration for FastSinkhorn: CUDA log-domain Sinkhorn using warp shuffle, shared-memory tiling
FastSinkhorn: CUDA log-domain Sinkhorn using warp...
Most algorithms branded as "fast" are just recompiled versions of old code; they hit a computational wall and fail. FastSinkhorn, detailed in a new arXiv preprint, was engineered differently. It targets a specific, grinding bottleneck in optimal transport: the need for extreme precision, which demands using a minuscule regularization parameter called epsilon.
Our solver operates entirely in the log-domain, enabling robust computation for regularization parameters as small as epsilon = 10^{-4} where standard-domain methods fail. On dense OT problems with n = m = 8192, our implementation achieves 12x speedup over the widely-used POT library and 5.9x speedup over GPU-accelerated PyTorch baselines, while consuming only 256 MB of GPU memory. We validate our solver on image color transfer, 3D point cloud matching, and convergence analysis, demonstrating that native CUDA kernels with careful numerical treatment provide a practical and efficient foundation for large-scale optimal transport computation.
The reported 12x speedup on dense 8192x8192 matrices transforms what's possible in a single workday. Coupled with a trivial 256 MB GPU memory footprint, this makes the method practical. The key insight, validated on tasks like image color transfer and 3D point cloud matching, is that performance hinges on numerical care—here, using log-domain math for stability—paired with hardware-aware tricks like CUDA warp shuffles.
A previously slow, fragile pipeline step becomes fast and robust. That's how real bottlenecks disappear.
Common Questions Answered
What computational bottleneck does FastSinkhorn address in optimal transport?
FastSinkhorn targets the need for extreme precision in optimal transport calculations, which requires using a minuscule regularization parameter called epsilon. This precision requirement has historically been a grinding bottleneck that limits computational efficiency in optimal transport algorithms.
How much speedup does FastSinkhorn achieve on dense matrices compared to traditional methods?
FastSinkhorn delivers a reported 12x speedup on dense 8192x8192 matrices, which significantly transforms what computational work can be accomplished in a single workday. This substantial performance improvement makes previously impractical optimal transport calculations feasible for real-world applications.
What hardware-aware techniques does FastSinkhorn use to improve performance?
FastSinkhorn employs CUDA-specific optimizations including warp shuffle operations, shared-memory tiling, and log-domain mathematics for numerical stability. These hardware-aware tricks are paired with careful numerical care to achieve optimal performance on GPU architectures.
What are the practical applications validated for FastSinkhorn's performance?
FastSinkhorn has been validated on tasks including image color transfer and 3D point cloud matching, demonstrating its effectiveness across different optimal transport use cases. The method's performance hinges on combining numerical stability through log-domain math with hardware-aware optimizations.
What is the GPU memory footprint required to run FastSinkhorn?
FastSinkhorn requires only a trivial 256 MB GPU memory footprint, making it practical for deployment on standard GPU hardware. This minimal memory requirement, combined with the 12x speedup on large matrices, makes the method accessible for real-world applications.
Further Reading
- Fast Log-Domain Sinkhorn Optimal Transport with Warp-Level GPU Reductions — arXiv
- ECE/ME/EMA/CS 759 High Performance Computing for Engineering Applications - CUDA Tiling and Memory Optimization — University of Wisconsin-Madison
- NVIDIA CUDA C Best Practices Guide - Memory Coalescing and Shared Memory Patterns — NVIDIA Developer Documentation