Gaussian processes (GPs) are flexible models with state-of-the-art performance on many impactful applications. However, computational constraints with standard inference procedures have limited exact GPs to problems with fewer than about ten thousand training points, necessitating approximations for larger datasets. In this paper, we develop a scalable approach for exact GPs that leverages multi-GPU parallelization and methods like linear conjugate gradients, accessing the kernel matrix only through matrix multiplication. By partitioning and distributing kernel matrix multiplies, we demonstrate that an exact GP can be trained on over a million points in 3 days using 8 GPUs and can compute predictive means and variances in under a second using 1 GPU at test time. Moreover, we perform the first-ever comparison of exact GPs against state-of-the-art scalable approximations on large-scale regression datasets with $10^4-10^6$ data points, showing dramatic performance improvements.

本文提出了一种可扩展的方法，利用多GPU并行化和线性共轭梯度等方法，仅通过矩阵乘法就可以访问核矩阵，将核矩阵乘法进行分区和分配，演示了可以在不到2小时内对超过一百万个点进行精确的高斯过程训练，并在规模上进行了比较，表现出显著的性能提升。

百万数据点上的精确高斯过程