A novel cache-utilization based dynamic voltage frequency scaling (DVFS) mechanism for reliability enhancements

We propose a cache architecture using a 7T/14T SRAM [1] and a control mechanism for reliability enhancements. Our control mechanism differs from the conventional DVFS methods, which considers not only the CPI behaviors but also the cache utilizations. To measure cache utilization, a novel metric is proposed. The experimental results show that our proposed method achieves thousand times less bit-error occurrences compared to the conventional DVFS methods under the ultra-low voltage operation. Moreover, the results show that our proposed method surprisingly not only incurs no performance and energy overheads but also achieves on an average 5.1% performance improvement and 5% energy reduction compared to the conventional DVFS methods.