MS-MPI V6.0 Beta announcement

We are happy to announce today the Beta release of the newest version of Microsoft MPI (MS-MPI). MS-MPI v6 Beta is the pre-release version for the successor to HPC Pack 2012 R2 MS-MPI Redistributable Package (v5.0, released IN November 2014). You can download a copy of MS-MPI v6 Beta from the download center at MS-MPI v6 Beta 1 . For regular product updates please visit our HPC TEAM BLOG.  For beta release feedback please contact us at

This Beta version of MS-MPI v6 includes the following features, improvements, and fixes:

  • Multi-job affinity support
    • -affinity_auto|-aa
    • Affinity option is added so mpiexec task can be assigned to a new/separate core that is not in use and avoid over subscribing of the cores.
    • This option works even without use of HPC PACK
    • MS-MPI v6 beta will work on HPC PACK 2012 R2 and any versions thereafter
    • To run two 4 core jobs on an 8 core machine, use as follows
      • Submit job as mpiexec –c 4 - aa –al sequential appname.exe

    • Support for MPI_THREAD_MULTIPLE mode on Windows Server 2012+ and Windows 8+ when calling the MPI_Init_thread initialization routine.
    • MPI_THREAD_MULTIPLE enables multithreaded applications to use MS-MPI from any application thread (like OpenMP threads). 
  • New features from MPI 3.0 standard published by MPI FORUM

    • Support for MPI_Mprobe, MPI_Mrecv, MPI_Improbe and MPI_Imrecv
    • Support for MPI_COUNT, to allow large datatypes to be properly represented in MPI_STATUS structures.
    • Support for MPI_Type_create_hindexed_block
    • Link to the MPI 3.0 standards documentation

Important: This software is a pre-release version for evaluation purposes only, and it should not be used in a production environment. Features and behavior can change before the final release.

Note: The SDK components for MS-MPI (headers and libraries) ship separately from the redistributable package binary files. The SDK components are also available in this Beta release. To learn more about MS-MPI, see Microsoft MPI on MSDN or for detailed questions please send us an email to

You can also find useful information, and ask your own questions, in the Windows HPC MPI Forum.