The nonuniform distribution of instruction-level and machine parallelism and its effect on performance

摘要

A methodology for quickly estimating machine performance is developed. A first-order estimate is based on the average degree of machine parallelism. A second-order model corrects for the effects of nonuniformities in instruction-level and machine parallelism and is shown to be accurate to within 15% for three widely different machine pipelines: the CRAY-1, the MultiTitan, and a dual-issue superscalar machine.