On expected and observed communication performance with MPI derived datatypes

摘要

We are interested in the cost of communicating simple, common, non-contiguous data layouts in various scenarios using the MPI derived datatype mechanism. Our aim is twofold. First, we provide a framework for studying communication performance for non-contiguous data layouts described with MPI derived datatypes in comparison to baseline performance with the same amount of contiguously stored data. Second, we explicate natural expectations on derived datatype communication performance that any MPI library implementation should arguably fulfill. These expectations are stated semi-formally as MPI datatype performance guidelines.