This page provides the current Release Notes for Intel® MPI Library. The notes are categorized by year, from newest to oldest, with individual releases listed within each year.
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Intel® MPI Library 2021 Update 19.0 - oneAPI 2026.2
What's New
- Linux: The closed source MLX libfabric provider is deprecated, starting with Intel® MPI 2021.19 the libfabric open source UCX provider will be used to support the UCX library
- Libfabric is no longer packaged within the Intel® MPI installation tree and is instead shipped as a separate oneAPI component. In standalone Intel® MPI installations, libfabric is still installed alongside Intel® MPI for convenience, but it is not part of the Intel® MPI directory layout in the same way as before.
- Removed PSM2/PSM3 support - still available in open source libfabric repository
- Added rxm/verbs support
- Added OPX provider support in IMPI
- I_MPI_OFI_INTERNAL is deprecated
- Added support for I_MPI_THREAD_SPLIT in the UCX provider
- Linux: Added XPMEM technical preview for point-to-point operations. Set I_MPI_SHM_XPMEM=1 to enable XPMEM support. Added three additional XPMEM control variables:
- I_MPI_SHM_XPMEM_LMT_THRESHOLD
- I_MPI_SHM_XPMEM_COOP_COPY_THRESHOLD
- I_MPI_SHM_XPMEM_COOP_COPY_CHUNK_SIZE
- Tuning for single-node and multi-node all-to-all algorithms
- Linux: Ubuntu 24.04 single node and multi-node support
- Platform recognition and shm transport support for upcoming Intel® CPU platforms
- Technical preview of a new CBWR mode, I_MPI_CBWR=3. Currently the implementation only supports MPI_ALLREDUCE together with MPI_SUM and MPI_DOUBLE or MPI_DOUBLE_PRECISION
- Windows: On Windows the variable I_MPI_PIN_RESPECT_INHERITANCE=0/1 is introduced to control the process prinning inheritance of child processes
- Bug fixes
Known Issues
Additional steps for pip installation
To install Intel® MPI Library 2021.19.0 (or any package that depends on it) from PyPi using pip, please install libfabric first from Intel repository:
pip install libfabric --index-url https://software.repos.intel.com/python/pypi
Then install the component you need, e.g.:
pip install impi_devel==2021.19.0
Not installing libfabric first will lead to an unresolved dependency error.
Installation without a version specifier (==) will install the highest available version for which all dependencies are resolved.
System Requirements
Hardware Requirements
Systems based on the Intel® 64 architecture, in particular:
- Intel® Core™ processor family or higher
- Intel® Xeon® Scalable processor family
- Intel® Xeon® 6 processor family
- 1 GB of RAM per rank (2 GB recommended)
- 1 GB of free hard disk space
Supported Accelerators (Linux only)
- Intel® Data Center GPU Max SeriesIntel® Arc™ Pro B-Series GPU. Nvidia* GPUs (minimal tested version is NVIDIA* Tesla P100).
Drivers and Libraries
- oneAPI Level Zero API 1.0.
- CUDA* Version 11.3 or higher.
Software Requirements
Linux* OS
- Red Hat* Enterprise Linux* 9.6, 9.7, 9.8, 10.x
- SUSE* Linux Enterprise Server* 15 SP5, 15 SP6, 15 SP7, 16.0
- Fedora* 43, 44
- Rocky Linux* 10
- Amazon* Linux 2026, 2025, 2023
- Ubuntu 24.04
Compilers
- GNU*: C, C++, Fortran 77 3.3 or newer, Fortran 95 4.8.0 or newer
- Intel® C++/Fortran Compiler 17.0 or newer
Debuggers
- Rogue Wave* Software
- TotalView* 6.8 or newerAllinea*
- DDT* 1.9.2 or newer
- GNU* Debuggers 7.4 or newer
Batch Systems
- Platform* LSF* 6.1 or newer
- Altair* PBS Pro* 7.1 or newer
- Torque* 1.2.0 or newer
- Parallelnavi* NQS* V2.0L10 or newer
- NetBatch* v6.x or newer
- SLURM* 1.2.21 or newer
- Univa* Grid Engine* 6.1 or newer
- IBM* LoadLeveler* 4.1.1.5 or newer
- Platform* Lava* 1.0
Fabric Software
- Open Fabric Interface (OFI): https://github.com/ofiwg/libfabric
- Minimum: OFI 2.6.0
- Recommend to use OFI provided with IMPI
Supported Languages
- For GNU* compilers: C, C++, Fortran
- For Intel® compilers: C, C++, Fortran
Clustered File Systems
- IBM Spectrum Scale* (GPFS*)
- LustreFS*PanFS*NFS* v3 or newer
Linux General Purpose Intel® GPUs (GPGPU) Driver:
For all Intel® GPUs, see this article, https://dgpu-docs.intel.com/, and follow the directions for your device.
Windows* OS
- Microsoft* Windows* Server 2019, 2022, 2025
- Microsoft* Windows* 10, 11
(SDK only) Compilers
- Intel® C++/Fortran Compiler 17.0 or newer
- Microsoft* Visual Studio* Compilers 2020
Batch systems
- Microsoft* Job Scheduler
- Altair* PBS Pro* 9.2 or newer
Fabric software
- Open Fabric Interface (OFI): https://github.com/ofiwg/libfabric
- Minimum: OFI 2.6.0
- Recommend to use OFI provided with Intel® MPI
Supported languages
- For GNU* compilers: C, C++, Fortran
- For Intel® compilers: C, C++, Fortran
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