Rotary-code: Efficient MDS Array Codes for RAID-6 Disk Arrays
نویسندگان
چکیده
Low encoding/decoding complexity is essential for practical RAID-6 storage systems. In this paper, we describe a new coding scheme, which we call Rotary-code, for RAID-6 disk arrays. We construct Rotarycode based on a bit matrix-vector product similar to the Reed-Solomon coding, and provide the geometry encoding method and detailed non-recursive decoding algorithms. The capability of two-disk fault-tolerance and the property of Maximum Distance Separable (MDS) are proved in Rotary-code. The key novelty in Rotary-code is that the Rotary-code has optimal encoding complexity and optimal decoding complexity comparing with existing RAID-6 codes. Key-Words: Array code; MDS; RAID; Two-disk fault-tolerance; Efficient decoding; Decoding complexity
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