Performance of MPI sends of non-contiguous data

Victor Eijkhout

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arXiv · 1809.10778

Performance of MPI sends of non-contiguous data

Victor Eijkhout

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Abstract

We present an experimental investigation of the performance of MPI derived datatypes. For messages up to the megabyte range most schemes perform comparably to each other and to manual copying into a regular send buffer. However, for large messages the internal buffering of MPI causes differences in efficiency. The optimal scheme is a combination of packing and derived types.

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Victor Eijkhout. 2018-09-27. Performance of MPI sends of non-contiguous data. https://arxiv.org/abs/1809.10778

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