The Harbinger PowerPC-based SCI multiprocessor: an interim status report

The Harbinger system is a PowerPC-based SCI multiprocessor system. In this multiprocessor, the non-uniform Memory Access (NUMA) paradigm results from a distributed shared memory system with several levels in the memory hierarchy. The development of the Harbinger system continues through a series of stages of both hardware and software design. The hardware development begins with a standard development system design and progresses from custom hardware with, initially, uniprocessor logic to, finally, multiprocessor shared memory logic. The software design progresses, first, from porting a commercial operating system to the standard development system to, later, our custom hardware SCI based shared-memory system.