==============
This package provides Python bindings for the Message Passing Interface (MPI_) standard. It is implemented on top of the MPI specification and exposes an API which grounds on the standard MPI-2 C++ bindings.
.. _MPI: https://www.mpi-forum.org
This package supports:
Convenient communication of any picklable Python object
Fast communication of Python object exposing the Python buffer interface (NumPy arrays, builtin bytes/string/array objects)
Process groups and communication domains
Parallel input/output:
Dynamic process management
One-sided operations
You can install the latest mpi4py release from its source distribution
at PyPI <https://pypi.org/project/mpi4py/>_ using pip::
$ python -m pip install mpi4py
You can also install the in-development version with::
$ python -m pip install git+https://github.com/mpi4py/mpi4py
or::
$ python -m pip install https://github.com/mpi4py/mpi4py/tarball/master
.. note::
Installing mpi4py from its source distribution (available at PyPI) or Git source code repository (available at GitHub) requires a C compiler and a working MPI implementation with development headers and libraries.
.. warning::
pip keeps previously built wheel files on its cache for future
reuse. If you want to reinstall the mpi4py package using a
different or updated MPI implementation, you have to either first
remove the cached wheel file with::
$ python -m pip cache remove mpi4py
or ask pip to disable the cache::
$ python -m pip install --no-cache-dir mpi4py
The conda-forge_ community provides ready-to-use binary packages
from an ever growing collection of software libraries built around the
multi-platform conda package manager. Four MPI implementations are
available on conda-forge: Open MPI (Linux and macOS), MPICH (Linux and
macOS), Intel MPI (Linux and Windows) and Microsoft MPI (Windows).
You can install mpi4py and your preferred MPI implementation using the
conda package manager:
to use MPICH do::
$ conda install -c conda-forge mpi4py mpich
to use Open MPI do::
$ conda install -c conda-forge mpi4py openmpi
to use Intel MPI do::
$ conda install -c conda-forge mpi4py impi_rt
to use Microsoft MPI do::
$ conda install -c conda-forge mpi4py msmpi
MPICH and many of its derivatives are ABI-compatible. You can provide
the package specification mpich=X.Y.*=external_* (where X and
Y are the major and minor version numbers) to request the conda
package manager to use system-provided MPICH (or derivative)
libraries. Similarly, you can provide the package specification
openmpi=X.Y.*=external_* to use system-provided Open MPI
libraries.
The openmpi package on conda-forge has built-in CUDA support, but
it is disabled by default. To enable it, follow the instruction
outlined during conda install. Additionally, UCX support is also
available once the ucx package is installed.
.. warning::
Binary conda-forge packages are built with a focus on
compatibility. The MPICH and Open MPI packages are build in a
constrained environment with relatively dated OS images. Therefore,
they may lack support for high-performance features like
cross-memory attach (XPMEM/CMA). In production scenarios, it is
recommended to use external (either custom-built or system-provided)
MPI installations. See the relevant conda-forge documentation about
using external MPI libraries <cf-mpi-docs_>_ .
.. _conda-forge: https://conda-forge.org/ .. _cf-mpi-docs: https://conda-forge.org/docs/user/tipsandtricks/#using-external-message-passing-interface-mpi-libraries
On Fedora Linux systems (as well as RHEL and their derivatives using the EPEL software repository), you can install binary packages with the system package manager:
using dnf and the mpich package::
$ sudo dnf install python3-mpi4py-mpich
using dnf and the openmpi package::
$ sudo dnf install python3-mpi4py-openmpi
Please remember to load the correct MPI module for your chosen MPI implementation:
for the mpich package do::
$ module load mpi/mpich-$(arch) $ python -c "from mpi4py import MPI"
for the openmpi package do::
$ module load mpi/openmpi-$(arch) $ python -c "from mpi4py import MPI"
On Ubuntu Linux and Debian Linux systems, binary packages are available for installation using the system package manager::
$ sudo apt install python3-mpi4py
Note that on Ubuntu/Debian systems, the mpi4py package uses Open
MPI. To use MPICH, install the libmpich-dev and python3-dev
packages (and any other required development tools). Afterwards,
install mpi4py from sources using pip.
macOS users can install mpi4py using the Homebrew_ package
manager::
$ brew install mpi4py
Note that the Homebrew mpi4py package uses Open MPI. Alternatively,
install the mpich package and next install mpi4py from sources
using pip.
.. _Homebrew: https://brew.sh/
Windows users can install mpi4py from binary wheels hosted on the
Python Package Index (PyPI) using pip::
$ python -m pip install mpi4py
The Windows wheels available on PyPI are specially crafted to work
with either the Intel MPI <I_MPI_>_ or the Microsoft MPI <MSMPI_>_
runtime, therefore requiring a separate installation of any one of
these packages.
.. IMPI: https://software.intel.com/intel-mpi-library .. _MSMPI: https://learn.microsoft.com/message-passing-interface/microsoft-mpi
Intel MPI is under active development and supports recent version of
the MPI standard. Intel MPI can be installed with pip (see the
impi-rt_ package on PyPI), being therefore straightforward to get it
up and running within a Python environment. Intel MPI can also be
installed system-wide as part of the Intel HPC Toolkit for Windows or
via standalone online/offline installers.
.. _impi-rt: https://pypi.org/project/impi-rt/
If MPI for Python been significant to a project that leads to an academic publication, please acknowledge that fact by citing the project.
M. Rogowski, S. Aseeri, D. Keyes, and L. Dalcin, mpi4py.futures: MPI-Based Asynchronous Task Execution for Python, IEEE Transactions on Parallel and Distributed Systems, 34(2):611-622, 2023. https://doi.org/10.1109/TPDS.2022.3225481
L. Dalcin and Y.-L. L. Fang, mpi4py: Status Update After 12 Years of Development, Computing in Science & Engineering, 23(4):47-54, 2021. https://doi.org/10.1109/MCSE.2021.3083216
L. Dalcin, P. Kler, R. Paz, and A. Cosimo, Parallel Distributed Computing using Python, Advances in Water Resources, 34(9):1124-1139, 2011. https://doi.org/10.1016/j.advwatres.2011.04.013
L. Dalcin, R. Paz, M. Storti, and J. D'Elia, MPI for Python: performance improvements and MPI-2 extensions, Journal of Parallel and Distributed Computing, 68(5):655-662, 2008. https://doi.org/10.1016/j.jpdc.2007.09.005
L. Dalcin, R. Paz, and M. Storti, MPI for Python, Journal of Parallel and Distributed Computing, 65(9):1108-1115, 2005. https://doi.org/10.1016/j.jpdc.2005.03.010