32-bit Python is not supported. Please install 64-bit version. If you have a strong need to install with 32-bit Python, refer to `Build 32-bit Version with 32-bit Python section <#build-32-bit-version-with-32-bit-python>`__.
Compiled library that is included in the wheel file supports both **GPU** and **CPU** versions out of the box. This feature is experimental and available only for **Windows** and **Linux** currently. To use **GPU** version you only need to install OpenCL Runtime libraries. For NVIDIA and AMD GPU they are included in the ordinary drivers for your graphics card, so no action is required. If you would like your AMD or Intel CPU to act like a GPU (for testing and debugging) you can install `AMD APP SDK <https://github.com/microsoft/LightGBM/releases/download/v2.0.12/AMD-APP-SDKInstaller-v3.0.130.135-GA-windows-F-x64.exe>`_ on **Windows** and `PoCL <http://portablecl.org>`_ on **Linux**. Many modern Linux distributions provide packages for PoCL, look for ``pocl-opencl-icd`` on Debian-based distributions and ``pocl`` on RedHat-based distributions.
For **Windows** users, `VC runtime <https://support.microsoft.com/en-us/help/2977003/the-latest-supported-visual-c-downloads>`_ is needed if **Visual Studio** (2015 or newer) is not installed.
In some rare cases, when you hit ``OSError: libgomp.so.1: cannot open shared object file: No such file or directory`` error during importing LightGBM, you need to install OpenMP runtime library separately (use your package manager and search for ``lib[g|i]omp`` for doing this).
- Starting from version 2.2.1, the library file in distribution wheels is built by the **Apple Clang** (Xcode_8.3.3 for versions 2.2.1 - 2.3.1, Xcode_9.4.1 for versions 2.3.2 - 3.3.2 and Xcode_11.7 from version 4.0.0) compiler. This means that you don't need to install the **gcc** compiler anymore. Instead of that you need to install the **OpenMP** library, which is required for running LightGBM on the system with the **Apple Clang** compiler. You can install the **OpenMP** library by the following command: ``brew install libomp``.
- For version smaller than 2.2.1 and not smaller than 2.1.2, **gcc-8** with **OpenMP** support must be installed first. Refer to `Installation Guide <https://github.com/microsoft/LightGBM/blob/master/docs/Installation-Guide.rst#gcc>`__ for installation of **gcc-8** with **OpenMP** support.
Also, in some rare cases you may need to install OpenMP runtime library separately (use your package manager and search for ``lib[g|i]omp`` for doing this).
- In case you prefer **Apple Clang**, you should install **OpenMP** (details for installation can be found in `Installation Guide <https://github.com/microsoft/LightGBM/blob/master/docs/Installation-Guide.rst#apple-clang>`__) first.
- In case you prefer **gcc**, you need to install it (details for installation can be found in `Installation Guide <https://github.com/microsoft/LightGBM/blob/master/docs/Installation-Guide.rst#gcc>`__) and specify compilers by running ``export CXX=g++-7 CC=gcc-7`` (replace "7" with version of **gcc** installed on your machine) first.
All requirements, except the **OpenMP** requirement, from `Build from Sources section <#build-from-sources>`__ apply for this installation option as well.
**MPI** libraries are needed: details for installation can be found in `Installation Guide <https://github.com/microsoft/LightGBM/blob/master/docs/Installation-Guide.rst#build-mpi-version>`__.
**Boost** and **OpenCL** are needed: details for installation can be found in `Installation Guide <https://github.com/microsoft/LightGBM/blob/master/docs/Installation-Guide.rst#build-gpu-version>`__. Almost always you also need to pass ``OpenCL_INCLUDE_DIR``, ``OpenCL_LIBRARY`` options for **Linux** and ``BOOST_ROOT``, ``BOOST_LIBRARYDIR`` options for **Windows** to **CMake** via ``pip`` options, like
For more details see `FindBoost <https://cmake.org/cmake/help/latest/module/FindBoost.html>`__ and `FindOpenCL <https://cmake.org/cmake/help/latest/module/FindOpenCL.html>`__.
**CUDA** library is needed: details for installation can be found in `Installation Guide <https://github.com/microsoft/LightGBM/blob/master/docs/Installation-Guide.rst#build-cuda-version>`__.
It is recommended to use **Visual Studio** for its better multithreading efficiency in **Windows** for many-core systems
(see `Question 4 <https://github.com/microsoft/LightGBM/blob/master/docs/FAQ.rst#4-i-am-using-windows-should-i-use-visual-studio-or-mingw-for-compiling-lightgbm>`__ and `Question 8 <https://github.com/microsoft/LightGBM/blob/master/docs/FAQ.rst#8-cpu-usage-is-low-like-10-in-windows-when-using-lightgbm-on-very-large-datasets-with-many-core-systems>`__).
By default, installation in environment with 32-bit Python is prohibited. However, you can remove this prohibition on your own risk by passing ``bit32`` option.
It is **strongly not recommended** to use this version of LightGBM!
For **Windows** users, if you get any errors during installation and there is the warning ``WARNING:LightGBM:Compilation with MSBuild from existing solution file failed.`` in the log.
Run ``sh ./build-python.sh install --nomp`` to disable **OpenMP** support. All requirements from `Build Threadless Version section <#build-threadless-version>`__ apply for this installation option as well.
Run ``sh ./build-python.sh install --mpi`` to enable **MPI** support. All requirements from `Build MPI Version section <#build-mpi-version>`__ apply for this installation option as well.
Run ``sh ./build-python.sh install --mingw``, if you want to use **MinGW-w64** on **Windows** instead of **Visual Studio**. All requirements from `Build with MinGW-w64 on Windows section <#build-with-mingw-w64-on-windows>`__ apply for this installation option as well.
Run ``sh ./build-python.sh install --gpu`` to enable GPU support. All requirements from `Build GPU Version section <#build-gpu-version>`__ apply for this installation option as well. To pass additional options to **CMake** use the following syntax: ``sh ./build-python.sh install --gpu --opencl-include-dir="/usr/local/cuda/include/"``, see `Build GPU Version section <#build-gpu-version>`__ for the complete list of them.
Run ``sh ./build-python.sh install --cuda`` to enable CUDA support. All requirements from `Build CUDA Version section <#build-cuda-version>`__ apply for this installation option as well.
Run ``sh ./build-python.sh install --bit32``, if you want to use 32-bit version. All requirements from `Build 32-bit Version with 32-bit Python section <#build-32-bit-version-with-32-bit-python>`__ apply for this installation option as well.
Run ``sh ./build-python.sh install --time-costs``, if you want to output time costs for different internal routines. All requirements from `Build with Time Costs Output section <#build-with-time-costs-output>`__ apply for this installation option as well.
If you get any errors during installation or due to any other reasons, you may want to build dynamic library from sources by any method you prefer (see `Installation Guide <https://github.com/microsoft/LightGBM/blob/master/docs/Installation-Guide.rst>`__) and then just run ``sh ./build-python.sh install --precompile``.