Design guidelines of storage class memory based solid-state drives to balance performance, power, endurance, and cost

摘要

The all storage-type storage-class memory (S-SCM) solid-state drive (SSD) and hybrid memory-type SCM (M-SCM)/NAND flash SSD (hybrid SSD) are two promising solutions for high performance storage. In this paper, the effect of wear leveling on the all S-SCM SSD performance, energy consumption, and endurance is evaluated. Furthermore, the all S-SCM SSD's performance dependency on S-SCM input/output (I/O) frequency and latency are discussed. From the experimental results, for the financial server application, the all S-SCM SSD has a higher performance than that of the hybrid SSD when S-SCM I/O frequency >200MHz and latency <5 mu s/sector. Last, the costs of the all S-SCM SSD and hybrid SSD are compared according to the cost of each memory device. Assuming the cost ratio of M-SCM and S-SCM to NAND flash is 10 and <3.25, respectively, the all S-SCM SSD is more cost-efficient than hybrid SSD with a 25% M-SCM/NAND capacity ratio. (C) 2015 The Japan Society of Applied Physics