Performance Expectations and Guidelines for MPI Derived Datatypes [chapter]

William Gropp, Torsten Hoefler, Rajeev Thakur, Jesper Larsson Träff
2011 Lecture Notes in Computer Science  
MPI's derived datatypes provide a powerful mechanism for concisely describing arbitrary, noncontiguous layouts of user data for use in MPI communication. This paper formulates self-consistent performance guidelines for derived datatypes. Such guidelines make performance expectations for derived datatypes explicit and suggest relevant optimizations to MPI implementers. We also identify self-consistent guidelines that are too strict to enforce, because they entail NP-hard optimization problems.
more » ... forced self-consistent guidelines assure the user that certain manual datatype optimizations cannot lead to performance improvements, which in turn contributes to performance portability between MPI implementations that behave in accordance with the guidelines. We present results of tests with several MPI implementations, which indicate that many of them violate the guidelines.
doi:10.1007/978-3-642-24449-0_18 fatcat:ei33led43fgsroc3xicsgbhbfi