An Overview of PLATINUM A Platform for Investigating Non-Uniform Memory (Preliminary Version)
Robert J. Fowler, Anna L. Cox · UR Research (University of Rochester) · 1988
PLATINUM is an experimental operating system kernel designed to facilitate research on memory management systems for Non-Uniform Memory Access (NUMA) Multiprocessor Architectures. It exports to user programs a simple abstraction of a shared memory multiprocessor in which all memory appears to be uniformly and rapidly accessible from all processors in the machine. The perceived uniformity on top of a non-uniform physical memory architecture is supported by an abstraction called coherent memory. Implemented in software as an extension of a directory-based caching mechanism using invalidation, coherent memory attempts to transparently migrate and replicate data to locations that are physically close to the processors that use it. A fundamental property of PLATINUM coherent memory is that it automatically reverts to the use of remote memory access for data that is not amenable to caching. PLATINUM currently runs on BBN Butterfly Plus Computers. This report is an overview of PLATINUM. In addition to motivating the project and presenting our research plans, we describe the interface that the kernel provides to its users.