KSR1 multiprocessor: analysis of latency hiding techniques in a sparse solver

Abstract

This paper analyzes and evaluates some novel latency hiding features of the KSR1 multiprocessor: prefetch and poststore instructions and automatic updates. As a case study, the authors analyze the performance of an iterative sparse solver which generates irregular communications. They show that automatic updates significantly reduce the amount of communication. Although prefetch and poststore instructions reduce the coherence miss ratios, they do not significantly improve the sparse solver performance due to the overhead in executing these instructions.<>