Strip-oriented asynchronous prefetching for parallel disk systems

作     者：Yang LIU Jian-zhong HUANG Xiao-dong SHI Qiang CAO Chang-sheng XIE 

作者机构：Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Wuhan 430074 China School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China 

出 版 物：《Journal of Zhejiang University-Science C(Computers and Electronics)》 (浙江大学学报C辑（计算机与电子（英文版）)

年 卷 期：2012年第13卷第11期

页      面：799-815页

核心收录：

学科分类：0810[工学-信息与通信工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 081201[工学-计算机系统结构] 0812[工学-计算机科学与技术（可授工学、理学学位）] 

基　　金：supported by the National Basic Research Program(973) of China (No. 2011CB302303) the National Natural Science Foundation of China (No. 60933002) the Fundamental Research Funds for the Central Universities,China (Nos.2012QN100 and 2011TUS-136) 

主　　题：Parallel disk system Strip Sequential prefetching Asynchronous scheduling 

摘      要：Sequential prefetching schemes are widely employed in storage servers to mask disk latency and improve system throughput. However, existing schemes cannot benefit parallel disk systems as expected due to the fact that they ignore the distinct internal characteristics of the parallel disk system, in particular, data striping. Moreover, their aggressive prefetching pattern suffers from premature evictions and prolonged request latencies. In this paper, we propose a strip-oriented asynchronous prefetching (SoAP) technique, which is dedicated to the parallel disk system. It settles the above-mentioned problems by providing multiple novel features, e.g., enhanced prediction accuracy, adaptive prefetching strength, physical data layout awareness, and timely prefetching. To validate SoAP, we implement a prototype by modifying the software redundant arrays of inexpensive disks (RAID) under Linux. Experimental results demonstrate that SoAP can consistently offer improved average response time and throughput to the parallel disk system under non-random workloads compared with STEP, SP, ASP, and Linux-like SEQPs.