THE COMPONENT ARCHITECTURE OF OPEN MPI: ENABLING THIRD-PARTY COLLECTIVE ALGORITHMS∗ Jeffrey M. Squyres and Andrew Lumsdaine Open Systems Laboratory, Indiana University Bloomington, Indiana, USA
[email protected] [email protected] Abstract As large-scale clusters become more distributed and heterogeneous, significant research interest has emerged in optimizing MPI collective operations because of the performance gains that can be realized. However, researchers wishing to develop new algorithms for MPI collective operations are typically faced with sig- nificant design, implementation, and logistical challenges. To address a number of needs in the MPI research community, Open MPI has been developed, a new MPI-2 implementation centered around a lightweight component architecture that provides a set of component frameworks for realizing collective algorithms, point-to-point communication, and other aspects of MPI implementations. In this paper, we focus on the collective algorithm component framework. The “coll” framework provides tools for researchers to easily design, implement, and exper- iment with new collective algorithms in the context of a production-quality MPI. Performance results with basic collective operations demonstrate that the com- ponent architecture of Open MPI does not introduce any performance penalty. Keywords: MPI implementation, Parallel computing, Component architecture, Collective algorithms, High performance 1. Introduction Although the performance of the MPI collective operations [6, 17] can be a large factor in the overall run-time of a parallel application, their optimiza- tion has not necessarily been a focus in some MPI implementations until re- ∗This work was supported by a grant from the Lilly Endowment and by National Science Foundation grant 0116050.