Run-Time Reconfiguration of Expandable Cache for Embedded Systems

Expandable cache proposed by Bournoutian and Orailoglu is very efficient in reducing miss rate and energy consumption with small area overhead. However, the original expandable cache with only one expansion scheme may lead to thrashing problems. In this work, based on the structure of expandable cache, we will introduce a new cache design which has many expansion schemes to fit different run-time program behaviors. The expansion scheme of our proposed cache is dynamically changed by executing configuration instructions which are inserted at compile time. The experimental results of SPEC CPU2000 have shown that our proposed cache design effectively improves the miss rate by 14.74% as compared with the original expandable cache. In terms of energy improvement ratio, our method is 5.62% higher than that of expandable cache when the baseline is set as the energy consumption of 2-way set-associative cache.