research relevant to the design and application of high performance scientific computers. We test our ideas by designing, building, and using real systems. The systems we build are research prototypes; they are not intended to become products. There two other research laboratories located in Palo Alto, the Network Systems

Advances in IC processing allow for more microprocessor design options. The increasing gate density and cost of wires in advanced integrated circuit technologies require that we look for new ways to use their capabilities effectively. This paper shows that in advanced technologies it is possible to implement a single-chip multiproces-sor in the same area as a wide issue superscalar processor. We find that for applications with little parallelism the performance of the two microarchitectures is comparable. For applications with large amounts of parallelism at both the fine and coarse grained levels, the multiprocessor microarchitectnre outperforms the superscrdar architecture by a significant margin. Single-chip multiprocessor architectures have the advantage in that they offer localized imple-mentation of a high-clock rate processor for inherently sequential applications and low latency interprocessor communication for par-allel applications. 1