SRC Research Report 51
SRC Research Report 51
Commercial multiprocessors are used successfully for a range of applications, including intensive numeric computations, time-sharing, and shared servers. The value of multiprocessing in a single-user workstation is not so obvious, especially in an environment where numeric problems do not dominate. The Digital Equipment Corporation Systems Research Center has had several years of experience using the five-processor Firefly workstation in such an environment. This report is an initial assessment of how much is gained from multiprocessing on the Firefly.
Reported here are measurements of speedup and utilization for a variety of programs. They illustrate four sources of concurrency: between independent tasks, within a server, between client and server, and within an application. The nature of the parallelism in each example is explored, as well as the factors, if any, that constrain multiprocessing. The examples cover a wide range of multiprocessing, with speedups on a five-processor machine varying from slightly over 1 to nearly 6. Most uses derive most of their speedup from two or three processors, but there are important applications that can effectively use five or more.
Back to the SRC Research Reports main page.