The BY91-1 Machine: A CC-NUMA Multiprocessor Architecture

BY91-1 machine is a prototype implementation of the CC-NUMA ( Cache Coherent Nonuniform Memory Access) multiprocessor architectures. Several mechanisms are combined to achieve its high performanc e: coherent shared memory provides a global, linear address space; versatile directory scheme ( Dir nNB+L) maintains both cache coherence and synchronization between processors in a uniform fashion; customized crossbar is optimized for high performance data transfers and signaling. This paper describes the experience gained by designing, fabricating, and running a complete parallel system. Specifically, it shows the effectiveness of the BY91-1 architecture and how the mechanisms are integrated to produce a coherent system