An Aging-Aware Early Cache Eviction Strategy to Enhance Static Random-Access Memory Cells’ Lifetime

This paper presents a comprehensive analysis of the impact of early cache eviction on the aging of cache cells. It highlights that, in addition to the previously identified factors contributing to static noise margin (SNM) degradation in cache cells, the state of cached data plays a critical role in this process. The analysis reveals that the uneven distribution of clean and dirty data blocks across the lines of a cache set can also be a significant factor in SNM degradation. To address this issue, this study proposes an early cache eviction strategy aimed at balancing the distribution of dirty and clean data blocks over cache lines, thereby mitigating SNM degradation. To achieve this, the decision tree of the Pseudo-LRU replacement policy is redesigned to incorporate cache line states and address conflict miss types. Experimental results demonstrate that the enhanced cache improves the hold and read SNM by approximately 10% and 12%, respectively, while incurring negligible cache hit reduction and minimal area and energy overheads.