A Technique For Improving Lifetime of Non-volatile Caches using Write-minimization

TitleA Technique For Improving Lifetime of Non-volatile Caches using Write-minimization
Publication TypeJournal Article
Year of Publication2016
AuthorsMittal, Sparsh, and Vetter Jeffrey
JournalMDPI Journal of Low Power Electronics and Applications (Special issue on Energy-efficient and Scalable Embedded Memories for Future Technologies)
Keywordscache, device lifetime, Non volatile memory, NVM, SRAM, Temporal locality, Write endurance, Write minimization

While non-volatile memories (NVMs) provide high-density and low-leakage, they also have low write-endurance. This, along with the write-variation introduced by the cache management policies can lead to very small cache lifetime. In this paper, we propose ENLIVE, a technique for improving the lifetime of NVM caches. Our technique uses a small SRAM storage, called HotStore. ENLIVE detects frequently written blocks and transfers them to the HotStore so that they can be accessed with smaller latency and energy. This also reduces the number of writes to the NVM cache which improves its lifetime. We present microarchitectural schemes for managing the HotStore. Simulations have been performed using an x86-64 simulator and benchmarks from SPEC2006 suite. We observe that ENLIVE provides higher improvement in lifetime and better performance and energy efficiency than two state-of-the-art techniques for improving NVM cache lifetime. ENLIVE provides 8.47X, 14.67X and 15.79X improvement in lifetime or 2, 4 and 8 core systems, respectively. Also, it works well for a range of system and algorithm parameters and incurs only small overhead.