That part of perf optimization refers to quantization step. If you want to quantize your model, you may want to follow this Quantization — PyTorch 1.9.0 documentation 3, (beta) Static Quantization with Eager Mode in PyTorch — PyTorch Tutorials 1.9.0+cu102 documentation, Quantization Recipe — PyTorch Tutorials 1.9.0+cu102 documentation. You can google “pytorch quantization” and get some more links.
If you are not trying to quantize the model then you can ignore that step.