뉴메모리와 SSD를 결합하여 구성한 하이브리드 캐시의 실험적 평가

Abstract

HDD(Hard Disk Drive), a secondary storage in general use, has been a bottleneck to the whole system. To solve this matter, a following technic is now favored: next-generation storage device named SSD(Solid State Drive) and next-generation memory technology so-called New memory are applied to implement cache assisting HDD. Using a single SSD to implement a cache, there will be a frequent writing problem in the cache that will likely shorten the life of SSD. This durability problem in SSD can be solved by hybrid cache: RAM saves frequently used data, while SSD takes care of the rest. However, it cannot guarantee credibility on system fault because RAM is volatile. To manage the credibility problem, this paper suggests a method using New memory instead of DRAM in hybrid cache. New memory has a similar property to DRAM in access speed, as a non-volatile device. Hybrid cache with New memory solves the durability problem in SSD, and guarantees reliability on system fault. Also in performance aspect, it doesn’t deteriorate in performance due to its access speed similar to DRAM. Through the experiment in this paper, the performance of hybrid cache is attested, and based on this result, we proved the efficiency of hybrid cache using New memory.