一种可行的优化降级读性能RAID-6 编码算法

中国民航大学学报

一种可行的优化降级读性能RAID-6 编码算法

来燃¹，冯兴杰¹，王晴²，李杰¹，焦文欢¹

（1. 中国民航大学信息网络中心，天津300300；2. 天津市大学软件学院信息化部，天津300387）

收稿日期:2018-02-15 修回日期:2018-05-08 出版日期:2018-08-25 发布日期:2018-10-25
作者简介:来燃（1990—），男，湖北随州人，助理工程师，硕士，研究方向为分布式存储、云存储安全等.
基金资助:
中国民航大学教育教学改革与研究重点项目（CAUC-2016-C1-02）；赛尔网络下一代互联网技术创新项目（2016-114）

Efficient RAID-6 MDS code for degraded reads optimization

LAI Ran¹, FENG Xingjie¹, WANG Qing², LI Jie¹, JIAO Wenhuan¹

(1. Information and Network Center, CAUC, Tianjin 300300, China; 2. Information Department, TJISE, Tianjin 300387, China)

Received:2018-02-15 Revised:2018-05-08 Online:2018-08-25 Published:2018-10-25

摘要/Abstract

摘要： 随着大数据时代的来临以及存储规模的不断扩大，现代数据中心对存储系统的可靠性要求越来越高。针对传统RAID-6 纠删码存储系统在降级模式下读操作性能不足的问题，提出一种优化降级读性能的RAID-6编码算法。利用水平码中连续数据元素更有可能共享相同水平校验链的特点，将X-码中对角校验链上数据元素的布局方式调整为水平方向，保持校验元素的位置及其计算方法不变，有效减小了降级读操作的额外I/O 开销。仿真结果表明，优化X-码在磁盘数量相同的情况下降级读性能优于RDP 码和X-码。

关键词: RAID-6, MDS 纠删码, 降级读

Abstract: With the coming of Big Data Era and the development of modern storage systems, there is a big challenge in the reliability of storage systems in modern data center. Due to the fact that most classic RAID-6 MDS codes have limitations on degraded reads, a new RAID-6 MDS erasure code for optimizing the degraded reads is proposed,which adjusts the diagonal layout of X-code to horizontal direction by taking advantage of horizontal codes while the continuous data elements are more likely to share the same horizontal parity chain for optimizing degraded reads. Experimental results show that the optimized X-code can efficiently reduce the additional I/O requests for degraded read operations. Especially, compared with RDP code and X-code, the optimized X-code can obtain an improved performance with the same number of disks.

Key words: RAID-6, MDS erasure codes, degraded reads

中图分类号:

V219
TP302.8

来燃，冯兴杰，王晴，李杰，焦文欢. 一种可行的优化降级读性能RAID-6 编码算法[J]. 中国民航大学学报.

LAI Ran, FENG Xingjie, WANG Qing, LI Jie, JIAO Wenhuan. Efficient RAID-6 MDS code for degraded reads optimization[J]. .

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