Hierarchical collectives (cf. MPI communicators tied to topologies, and collecting over these). Part of FCA.
FCA is a MPI-integrated software package that utilizes CORE-Direct technology for implementing the MPI collective communications. FCA can be used with all major commercial and open-source MPI solutions that exist and being used for high-performance applications. FCA with CORE-Direct technology accelerates the MPI collectives runtime, increases the CPU availability to the application and allows overlap of communications and computations with collective operations. FCA allows for efficient collectives communication flow optimized to job and topology. It also contains support to build runtime configurable hierarchical collectives (HCOL) and supports multiple optimizations within a single collective algorithm.
module load cv-standard
Installed by Cluster Vision.
module load hcoll/3.5
Example Job Scripts