Characterizations and Architectural Implications of NVM's External DRAM Cache
Haiyang Pan, Yuhang Liu, Tianyue Lu, Mingyu Chen · 2019
To meet the memory capacity requirement of big-data applications, a promising architecture is that NVM (Non-Volatile Memory) is used as main memory and external DRAM (off-chip) is used as cache. Compared to LLC versus DRAM (referred to as L-DRAM), external DRAM cache versus NVM main memory (referred to as E-NVM) are significantly different in terms of capacity and latency, thus traditional design cannot be directly borrowed without reconsideration. In this paper, we explore the characteristics and architectural implications of E-NVM in diverse dimensions including cache line granularity, associativity, replacement policy and prefetching methods. Lots of hints have been found for the optimal design of this emerging architecture.