GPU-enabled package builds

[jack-pappas]

Comment:

I'm interested in comparing CPU vs. GPU performance across some of the popular ML libraries. I went to set up a conda environment to do this and realized that although lightgbm implements GPU support, this feedstock isn't building the package with it enabled.

conda-forge has other feedstocks that're building both _cpu and _cuda versions of packages. For example:

• conda-forge/arrow-cpp-feedstock
• conda-forge/xgboost-feedstock

It'd be great to have this feedstock building for both CPU and GPU in the same way.

Thanks!

N.B. This is a duplicate of #29, which was inexplicably closed.

[jameslamb]

👋🏻 Hi, I'm from LightGBM. I didn't know there were separate py-xgboost-cpu and py-xgboost-gpu packages available via conda-forge! Supporting an option like that for lightgbm would definitely be valuable.

I'm not that experience with repacking anything other than pure Python stuff for conda-forge, but if maintainers of this feedstock want to pursue this idea I'd be happy to be help out with LightGBM build toolchain questions.

Also just want to note that there are technically 2 totally different GPU implementations of lightgbm:

• "GPU" = based on OpenCL (targeting a wide range of hardware vendors), tested on every commit but not actively maintained
• "CUDA" = from-scratch CUDA kernel reimplementation of LightGBM (NVIDIA GPUs only), actively maintained

I think the most effective use of the limited time of anyone reading this is to focus on packaging the LightGBM CUDA implementation as py-lightgbm-cuda.

[isuruf]

@jameslamb, would it make sense to enable "GPU" (OpenCL) builds by default since OpenCL is a light dependency? Then we would need only two variants (CPU + GPU-OpenCL, CUDA) vs three (CPU, GPU-OpenCL, CUDA)

[jameslamb]

I think that's a great idea! That's similar to how LightGBM is packaged for PyPI... Linux and Windows wheels there come with OpenCL-based GPU support already compiled in.

I'd be happy to give a more thoughtful review on #55, but it'll be a day or 2 until I have the time.

[isuruf]

Fixed in #55