LAUSR

This letter studies the performance of ensemble of Regenerating codes and Replication (RR). It theoretically analyzes the storage-bandwidth tradeoff curve of RR, and attains two extremal cases, corresponding to minimum storage cost RR (MSRR) and minimum repair bandwidth RR (MBRR), respectively. Compared with the case of independently applying regenerating codes, the evaluation results indicate, with extra storage cost, MSRR has better average repair bandwidth and average disk I/O, and MBRR has less average disk I/O cost and almost the same level of average repair bandwidth, i.e., when satisfying the data available probability $P=0.9999$ , MSRR achieves at least 5.6% and 50%, and MBRR achieves at least 23.7% and 1.3% less disk I/O and repair bandwidth consumption in evaluation data sets, respectively.