pytorch-cpp-example

Sample scripts for testing PyTorch models in C++. Both CPU & GPU implementations are provided.

Author: Muralikrishnan Gopalakrishnan Meena (Oak Ridge National Laboratory), https://sites.google.com/view/muraligm/

Contributors:

• Murali Gopalakrishnan Meena
• Matt Norman (Oak Ridge National Laboratory), https://mrnorman.github.io/

Description

These are sample scripts to load a PyTorch model and run a forward step. These are adapted from PyTorch's docs for loading a Torch Script model in C++. They also have instructions in the doc to convert a PyTorch model to torch script in Python.

There are 2 examples:

1. CPU implementation example_pytorchNN_cpu.cpp
2. GPU implementation example_pytorchNN_gpu.cpp

For more details on the PyTorch C++ frontend API used in these scripts, refer to torch_interface.h.

The sample model used here, PyTorch_model_Cpp.pt, is for a fluid flow emulator which takes 36 inputs and gives 4 outputs.

Usage

1. Go to the build folder

   cd build
   

2. Activate binaries using environment file corresponding to your machine

   source <machineName>_<cpu/gpu>.env
   

   Example: For running on GPU on Summit

   source summit_gpu.env
   

3. Compile:

   ./cmakescript
   make -j
   

4. Run:

   ./example
   

• Sample output for the GPU usage (example_pytorchNN_gpu.cpp)

  Model loaded succefully!
  Number of CUDA devices: 1
  Sample output (scaled flow properties): -0.95627  4.08107  -2.88555  -0.970117