The Open MPI Project has spawned multiple sub-projects that are not directly part of MPI, but are related to HPC issues and are therefore of interested to the general HPC / open-source community.

Current projects

Portable Hardware Locality (hwloc)
Portable Network Locality (netloc)
The MPI Testing Tool (MTT)
Open Tool for Parameter Optimization (OTPO)

Deprecated / inactive sub-projects

Portable Linux Processor Affinity (PLPA) (now deprecated by hwloc)

Open MPI is an Associated Project
of the Software in the Public Interest non-profit organization