A repair-efficient coding for distributed storage systems under piggybacking framework

Piggybacking is an efficient framework to reduce the repair bandwidth of distributed storage systems, especially, when the systems meet the settings-maximum distance separable (MDS), high code rate, and a small number of substripes. Through an analysis on the repair ratio of a piggybacking construction, this paper reveals that the proportion p-{p} of piggybacking protected stripes is the key to significantly decrease the repair bandwidth. Based on this analysis, this paper proposes a repair efficient coding under piggybacking framework (REPB) by considering various piggybacking protected stripes and MDS only protected stripes. The repair ratio of REPB tends to 0 and is close to theoretical cut-set bound, as the proportion p-{p} is no longer fixed at 1/2. Furthermore, the proposed REPB codes enjoy low computational complexity in repair operation.