Yes, you can use nvprof to find out which convolution algorithm was used.
On your gpu machine: nvprof -o prof.nvvp python train_mnist.py
Then copy the prof.nvvp to your local machine and run: nvvp prof.nvvp
More details can be found here: https://gist.github.com/sonots/5abc0bccec2010ac69ff74788b265086 2
Indeed, it seem like a change in the convolution algorithm. By the way, you cannot select/check which convolution is used in PyTorch, as far as I know. Could anybody confirm that or give some more details how to do it? Moreover, there is an optimizer run by NVidia to select the most optimal convolution algorithm, and sometimes the optimizer tests a few convolutions before making the final choice, see: https://arxiv.org/pdf/1602.08124.pdf You can also control which convolution algorithm is used on the CUDA level: http://www.goldsborough.me/cuda/ml/cudnn/c++/2017/10/01/14-37-23-convolutions_with_cudnn/ 1