Open MPI v6.0.x series
======================

This file contains all the NEWS updates for the Open MPI v6.0.x
series, in reverse chronological order.

Open MPI version v6.0.0
--------------------------
:Date: ...fill me in...

- Added support for the MPI-4.0 embiggened APIs (i.e., functions with
  ``MPI_Count`` parameters).

- Fix build system and some internal code to support compiler
  link-time optimization (LTO).

- Open MPI now requires a C11-compliant compiler to build.

- Open MPI now requires Python >= |python_min_version| to build.

  - Open MPI has always required Perl 5 to build (and still does); our
    Perl scripts are slowly being converted to Python.

  .. note:: Open MPI only requires Python >= |python_min_version| and
            Perl 5 to build itself.  It does *not* require Python or
            Perl to build or run Open MPI or OSHMEM applications.

- Removed the ROMIO package.  All MPI-IO functionality is now
  delivered through the Open MPI internal "OMPIO" implementation
  (which has been the default for quite a while, anyway).

- Added support for MPI-4.1 functions to access and update ``MPI_Status``
  fields.

- MPI-4.1 has deprecated the use of the Fortran ``mpif.h`` include
  file.  Open MPI will now issue a warning when the file is included
  and the Fortran compiler supports the ``#warning`` directive.

- Added support for the MPI-4.1 memory allocation kind info object and
  values introduced in the MPI Memory Allocation Kinds side-document.

- Added support for Intel Ponte Vecchio GPUs.

- Extended the functionality of the accelerator framework to support
  intra-node device-to-device transfers for AMD and NVIDIA GPUs
  (independent of UCX or Libfabric).

- Added support for MPI sessions when using UCX.

- Added support for MPI-4.1 ``MPI_REQUEST_GET_STATUS_[ALL|ANY_SOME]`` functions.

- Improvements to collective operations:
  
  - Added new ``xhc`` collective component to optimize shared memory collective
    operations using XPMEM.

  - Added new ``acoll`` collective component optimizing single-node
    collective operations on AMD Zen-based processors.

  - Added new algorithms to optimize Alltoall and Alltoallv in the
    ``han`` component when XPMEM is available.

  - Introduced new algorithms and parameterizations for Reduce, Allgather,
    and Allreduce in the base collective component, and adjusted the ``tuned``
    component to better utilize these collectives.

  - Added new JSON file format to tune the ``tuned`` collective component.

  - Extended the ``accelerator`` collective component to support
    more collective operations on device buffers.