Seek-Efficient I/O Optimization in Single Failure Recovery for XOR-Coded Storage Systems

• Published in: IEEE transactions on parallel and distributed systems Vol. 28; no. 3; pp. 877 - 890
• Main Authors: Shen, Zhirong, Shu, Jiwu, Lee, Patrick P. C., Fu, Yingxun
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.03.2017; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Data recovery; Disk drives; disk seeks; Distributed databases; Encoding; Enumeration; Failure; Generators; greedy algorithm; Layout; Maintenance engineering; Optimization; Redundancy; repair traffic; single failure fecovery; State of the art; Storage systems; Strips; System effectiveness; Tabu search; XOR-Coded storage systems
• ISSN: 1045-9219; 1558-2183
• DOI: 10.1109/TPDS.2016.2591040

Erasure coding provides an effective means for storage systems to protect against disk failures with low redundancy. One important objective for erasure-coded storage systems is to speed up single disk failure recovery. Previous approaches reduce the amount of read data for recovery by reading only a small subset of data. However, they often incur high disk seeks, which may negate the resulting recovery performance. We propose SIOR , a seek-efficient I/O recovery algorithm for improving the performance of single disk failure recovery. SIOR carefully balances the trade-off between the amount of read data and the number of disk seeks by considering the data layout at the multi-stripe level. It then greedily determines the data to read for recovery using Tabu search. Experiments show that SIOR achieves similar performance to the brute-force enumeration method while keeping high search efficiency. Also, SIOR reduces <inline-formula><tex-math notation="LaTeX">31.8\sim 65.1</tex-math> <inline-graphic xlink:href="shen-ieq1-2591040.gif"/> </inline-formula> percent of disk seeks during recovery and provides up to 150.0 percent recovery speed improvement, when compared to a state-of-the-art greedy recovery approach.