Frequent Access Pattern-based Prefetching Inside of Solid-State Drives
Xiaofei Xu1, Zhigang Cai1, Jianwei Liao1,2,a and Yutaka Ishiakwa3
1College of Computer and Information Science, Southwest University, Chongqing, China
2The State Key Laboratory for Novel Software Technology Nanjing University, Jiangsu
3RIKEN Center for Computational Science, Kobe, Japan
aliaotoad@gmail.com
ABSTRACT
This paper proposes an SSD-inside data prefetching scheme, which has features of OS-dependence and use transparency. To be specific, it first mines frequent block access patterns that reflect the correlation among the occurred requests. Then it compares the requests in the current time window with the identified patterns, to direct fetching data in advance. Furthermore, to maximize the cache use efficiency, we construct a method to adaptively determine the cache partition on the basis of I/O workload characteristics, for separately buffering the prefetched data and the write data. Experimental results demonstrate that our proposal can yield improvements on average read latency by 6.3% to 9.3% without noticeably increasing write latency, in contrast to conventional SSD-inside prefetching schemes.
Keywords: SSD Cache, Frequent Access Pattern, Prefetching, Adaptive Cache Replacement, I/O Time
