Dynamic Adjustment of Storage Class Memory Capacity in Memory-Resource Disaggregated Hybrid Storage With SCM and NAND Flash Memory

摘要

Using storage class memories (SCMs) as nonvolatile cache of NAND flash memory is a promising solution for the high-performance storage. However, the problem is the high SCM cost per bit which is about ten times higher than NAND flash and the optimal SCM capacity is application dependent. The optimum SCM capacity is conventionally determined manually for every application operating on the data centers' storages. To achieve high performance while reducing the overall storage cost, application-aware autonomous SCM capacity adjustment (3ASCA) method is utilized to observe the warm data in NAND flash by the ghost least recently used list. SCM capacity in the memory-resource disaggregated storage with hybrid use of SCM and NAND flash is autonomously adjusted and effectively utilized for different applications. By saving the SCM capacity with 3ASCA, multiple applications in the disaggregated storage can efficiently utilize the limited SCM capacity at the same time.