Blue Gene
Blue Gene/L (BG/L) is a 64K (65,536) node scientific and engineering supercomputer that IBM is developing with partial funding from the United States Department of Energy. This paper describes one of the primary BG/L interconnection networks, a three dimensional torus. We describe a parallel performance simulator that was used extensively to help architect and design the torus network and present sample simulator performance studies that contributed to design decisions. In addition to such studies, the simulator was also used during the logic verification phase of BG/L for performance verification, and its use there uncovered a bug in the VHDL implementation of one
of the arbiters. Blue Gene/L (BG/L) is a scientific and engineering, message-passing, supercomputer that IBM is developing with partial funding from the U.S. Department of Energy Lawrence Livermore National Laboratory. A 64K node system is scheduled to be delivered to Livermore, while a 20K node system will be installed at the IBM T.J. Watson Research Center for use in life sciences computing, primarily protein folding. A more complete overview of BG/L may be found in [1], but we briefly describe the primary features of the machine.