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10
• Improved CUDA support when using UCX.
• Enable use of CUDA allocated buffers for OMPIO.
• Improved support for two phase MPI I/O operations when using OMPIO.
• Improvements to MPI RMA performance when using RDMA capable interconnects.
• Improved multi-threaded performance of UCX OSC component.
• Updated internal HWLOC to 2.0.2
• Updated internal PMIx to 3.0.2
• Updated internal ROMIO to 3.2.1.
• Update memkind component to use the memkind 1.6 public API.
• Added support for Software-based Performance Counters, see
https://github.com/davideberius/ompi/wiki/How-to-Use-Software-Based-Performance-Counters-(SPCs)-in-Open-MPI
• OSHMEM updated to the OpenSHMEM 1.4 API.
• OpenIB BTL now only supports iWarp and RoCE by default.
• Change the priority for selecting external verses internal HWLOC and PMIx packages to build. Starting with this release,
configure by default selects available external HWLOC and PMIx packages over the internal ones.
• Removed support for the MXM MTL.
• Removed support for SCIF.
Open MPI Versions – what was new v4.0.x