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E. Bajrovic, J. Träff:
"Using MPI Derived Datatypes in Numerical Libraries";
Talk: EuroMPI 2011, Santorini, Greece; 2011-09-18 - 2011-09-21.

By way of example this paper examines the potential of MPI
user-defined datatypes for distributed datastructure manipulation in numerical libraries. The three examples, namely gather/scatter of columnwise distributed two dimensional matrices, matrix transposition, and redistribution of doubly cyclically distributed matrices as used in the Elemental dense matrix library, show that distributed data structures can be conveniently expressed with the derived datatype mechanisms of MPI, yielding at the same time worthwhile performance advantages over straight-forward, handwritten implementations. Experiments have been performed with on different systems with mpich2 and OpenMPI library implementations. We report results for a SunFire X4100 system with the mvapich2 library. We point out cases where the current MPI collective interfaces do not provide sufficient functionality.