A New Computer Architecture Strategy: The “Blue Planet” Proposal

In recent years scientific computing in America has been handicapped by its dependence on hardware that is designed and optimized for commercial applications. The performance of the recently completed Earth Simulator in Japan, which is five times faster than the fastest American supercomputer, dramatically exposed the seriousness of this problem. Typical scientific applications are now able to extract only 5 to 10 percent of the power of American supercomputers built from commercial Web and data servers. By contrast, the design of the Earth Simulator makes 30 to 50 percent of its power accessible to the majority of types of scientific calculations.

It is becoming increasingly clear that the requirements of high performance computing (HPC) for science and engineering, and the requirements of the commercial market are diverging. This divergence can be seen in some computer vendors’ reduced interest in the HPC market as well as in the performance limitations of clusters of symmetric multiprocessors (SMPs) used for scientific applications. Communications and memory bandwidth in SMPs are not scaling with processor power, which constrains the performance of scientific codes. The cost of scientific supercomputing, with nearly football-field size computers that consume megawatts of electricity, is also an issue of national strategic importance.

Lawrence Berkeley and Argonne national laboratories, in close collaboration with IBM, have responded to this challenge with a proposal for a new program to bring into existence a new class of computational capability in the United States that is optimal for science. Our strategic white paper, “Creating Science-Driven Computer Architecture: A New Path to Scientific Leadership”, envisions a new type of development partnership with computer vendors that goes beyond the mere evaluation of the offerings that those vendors are currently planning for the next decade. This strategy includes development partnerships with multiple vendors, in which teams of scientific applications specialists and computer scientists will work with computer architects from major U.S. vendors to create hardware and software environments that will allow scientists to extract the maximum performance and capability from the hardware.

	Figure 2   Blue Planet was born here: At a two-day workshop in September 2002, a team of Argonne, Berkeley Lab, and IBM scientists developed the fundamental concepts of Virtual Vector Architecture (ViVA), potentially redefining supercomputing in America.

One the key partnerships, involving IBM, Lawrence Berkeley National Laboratory, and the NERSC Center, will deploy a new architecture called ViVA or Virtual Vector Architecture. This architecture will use commercial microprocessors but will run programs optimized for vector processors, providing both high sustained levels of performance and cost-effectiveness. Blue Planet, a 160 teraflop/s mature implementation of ViVA, has been proposed for installation at NERSC in the second half of 2005. Blue Planet is expected to provide twice the sustained capability of the Earth Simulator at half the cost. Computer scientists from Berkeley Lab/NERSC, Argonne, and IBM held two workshops in September and November 2002 (Figure 2), the first to define the Blue Planet architecture, and the second for IBM to receive scientists’ suggestions on the design of the Power 6 processor.