Fast Collective Communication Libraries, Please

Prasenjit Mitra
Department of Computer Sciences
University of Texas
Austin, TX 78712
prasen@cs.utexas.edu
David Payne
Scalable Systems Division
Intel Corporation
15201 N.W. Greenbrier Pkwy
Beaverton, OR 97006
payne@ccsf.caltech.edu
Lance Shuler
Parallel Computing Sciences Department, 1424
Sandia National Laboratory
Albuquerque, New Mexico 87185-1109
shuler@cs.sandia.gov
Robert A. van de Geijn
Department of Computer Sciences
University of Texas
Austin, TX 78712
rvdg@cs.utexas.edu
Jerrell Watts
Scalable Concurrent Programming Laboratory
California Institute of Technology
Pasadena, California 91125
jwatts@scp.caltech.edu

Abstract

It has been recognized that many parallel numerical algorithms can be effectively implemented by formulating the required communication as collective communications. Nonetheless, the efficiency of such communications has been suboptimal in many communication library implementations. In this paper, we give a brief overview of techniques that can be used to implement a high performance collective communication library, the iCC library, developed for the Intel family of parallel supercomputers as part of the InterCom project at the University of Texas at Austin. We compare the achieved performance on the Intel Paragon to those of three widely available libraries: Intel's NX collective communication library, the MPICH Message Passing Interface (MPI) implementation developed at Argonne and Mississippi State University and a Basic Linear Algebra Communication Subprograms (BLACS) implementation, developed at the University of Tennessee.

Prasenjit Mitra, David Payne, Lance Shuler, Robert van de Geijn, and Jerrell Watts, `Fast Collective Communication Libraries, Please," to appear in the Proceedings of the Intel Supercomputing Users' Group Meeting 1995.

Prasenjit Mitra, David Payne, Lance Shuler, Robert van de Geijn, and Jerrell Watts, "Fast Collective Communication Libraries, Please," Department of Computer Sciences, The Unversity of Texas, TR-95-22, June 1995.

For further information, see also the InterCom web page