Impact of Technology Scaling on Energy Aware Execution Cache-Based Microarchitectures

Reducing total power consumption in high performance microprocessors can be achieved by limiting the amount of logic involved in decoding, scheduling and executing each instruction. One of the solutions to this problem involves the use of a microarchitecture based on an Execution Cache (EC) whose role is to cache already done work for later reuse. In this paper, we explore the design space for such a microarchitecture, looking at how the cache size, associativity and replacement algorithm affect the overall performance and power efficiency. We also look at the scalability of this solution across next process generations, evaluating the energy efficiency of such caching mechanisms in the presence of increasing leakage power. Over a spectrum of SPEC2000 benchmarks, an average of 35% energy reduction is achieved for technologies ranging from 130nm to 90nm and 65nm, at the expense of a negligible performance hit.