A new preview release of MPICH, 3.3a2, is now available for download. This preview release is for the 3.3 major release series. Of major focus in this alpha is an new (non-default) device layer implementation - CH4. CH4 is designed for low software overheads to better exploit next-generation hardware. An OFI (http://libfabric.org) or UCX (http://openucx.org) library is required to build CH4. Example configure lines: ./configure --with-device=ch4:ofi --with-libfabric=<path/to/ofi/install> ./configure --with-device=ch4:ucx --with-ucx=<path/to/ucx/install> CH4 is still in alpha stages, meaning there are known build issues and bugs, but most tests and common benchmarks will complete on 64-bit Linux systems. Since 3.3a1, there have been major stability improvements, bug fixes, and code cleanup in CH4. CH4 support for Blue Gene/Q is added in this release (via the OFI/BGQ provider), as well as Mac OS builds. Also in this release are several bug fixes and improvements to CH3, Hydra, and common MPICH code. You can find the release on our downloads page (http://www.mpich.org/downloads). Regards, The MPICH team =============================================================================== Changes in 3.3 =============================================================================== # CH4 Device: A new device layer implementation designed for low software overheads. CH4 has experimental support for OFI and UCX network libraries, and POSIX shared memory. Thanks to Intel, Mellanox, and RIKEN AICS for participating in the CH4 coding effort. # Removed the PAMI device and poe PMI client. # Several other minor bug fixes, memory leak fixes, and code cleanup. A full list of changes is available at the following link: http://git.mpich.org/mpich.git/shortlog/v3.2..v3.3a2 A full list of bugs that have been fixed is available at the following link: https://github.com/pmodels/mpich/milestone/25