Performance evaluation of a multiprocessor under interactive workloads
Patrick F. McGehearty · 1980
In this work, I study the performance of a symmetrical multiprocessor in a conventional interactive environment. Measurements are made of the multiprocessor, C.mmp, running under the operating system Hydra over a variety of workloads. The workloads are synthetic, but based on typical workloads found on existing interactive systems. A detailed simulation model of C.mmp/Hydra is developed and validated for the above measurements. The model is used to study a wider range of possible systems than can be examined directly with the available hardware/software configurations. I present results based on both measurements and models that apply to the class of symmetrical multiprocessors on the following issues: (1) The relationship between the number of processors and the level of hardware and software contention. (2) The effect of system paging bandwidth on system performance. (3) The amount of primary memory needed to achieve given levels of performance. Particular emphasis is given to examining the effect of varying the number of processors in the system on these results. I also discuss performance results specific to C.mmp/Hydra including specific overheads and anomalies.