Optimized fast data migration for hybrid DRAM/STT-MRAM main memory

Abstract

In order to reduce the main memory energy of the IoT terminal, STT-MRAM is used to replace DRAM to save refresh energy. However, the write performance of STT-MRAM cells is worse than that of DRAM. Our previous work proposed a hybrid DRAM/STT-MRAM main memory and fast data migration to reduce the adverse effects of poor write performance of STT-MRAM cells with negligible performance overhead. This article optimizes the migration algorithm and experiment scheme: 1. Reduce the storage overhead of the algorithm. 2. Realize the continuous work of the algorithm. 3. Consider the impact of system standby time on main memory energy. The results show that compared with our previous work, the storage overhead of the algorithm is reduced 99.8%. When the system standby time is zero, the energy of the hybrid main memory (including the energy of the algorithm) is reduced by 4% on average compared to DRAM. The longer the system standby time, the more energy saving.