Building and Optimizing MRAM-Based Commodity Memories
Jue Wang, Xiangyu Dong, Yuan Xie · ACM Transactions on Architecture and Code Optimization · 2014
Emerging non-volatile memory technologies such as MRAM are promising design solutions for energy-efficient memory architecture, especially for mobile systems. However, building commodity MRAM by reusing DRAM designs is not straightforward. The existing memory interfaces are incompatible with MRAM small page size, and they fail to leverage MRAM unique properties, causing unnecessary performance and energy overhead. In this article, we propose four techniques to enable and optimize an LPDDRx-compatible MRAM solution: ComboAS to solve the pin incompatibility; DynLat to avoid unnecessary access latencies; and EarlyPA and BufW to further improve performance by exploiting the MRAM unique features of non-destructive read and independent write path. Combining all these techniques together, we boost the MRAM performance by 17% and provide a DRAM-compatible MRAM solution consuming 21% less energy.