Pytorch 1.2.0, pytorch 1.7.0, dilated conv

I used PyTorch 1.2.0 to train a semantic segmentation model, which used dilated Conv. Using pytorch1.2.0 to load the model for reasoning, the speed and effects are normal. But now using pytorch1.7.0 to load the model for reasoning, speed will be more than a hundred times slower than the former. What is the problem?