The UNIX system: Multiprocessor UNIX operating systems

This paper describes the problems posed by running the UNIX™ operating system on multiprocessors, as well as some solutions. The resulting systems function like their single-processor counterparts but yield 70 percent better throughput for two-processor configurations. Closely coupled multiprocessor UNIX systems currently run on IBM and AT&T Technologies hardware, but the implementation described in this paper ports to other architectures as well, and the design is not limited to two-processor configurations.