A New Family of Wide Locally Repairable Codes for Seeking the Trade-off between Fault Tolerance and Repair Degree in Distributed Storage System
Yan Wang, Junhao Shi, Hao Wang, Yanghuang Cao · 2024
Locally repairable codes (LRC) have dominated the coding design of erasure coding in wide stripes due to their excellent local property and low bandwidth requirement. In distributed storage systems, repair degree usually refers to the number of helper nodes that need to be contacted in data repair process. As the stripe becomes wider, the probability of multiple nodes failing simultaneously in the LRC increases, which leads to a significant increase in the repair degree. So how to improve the existing schemes to improve code reliability and reduce the repair degree in case of multiple failures remains to be further explored. In this paper, we present a new family of locally repairable codes, TFR-LRC (Locally Repairable Codes for seeking the Trade-off between Fault tolerance and Repair degree), which can achieve different trade-offs between fault tolerance and repair cost. TFR-LRC can sacrifice a little bit of storage cost for lower repair degree, and can sacrifice a little bit of repair cost for higher fault tolerance. In order to verify the feasibility of TFR-LRC, we conducted simulation experiments. The results show that, compared to the existing LRC schemes, TFR-LRC can greatly reduce the repair degree in case of multiple failures by sacrificing a little bit of storage cost without changing the traditional LRC structures, and meanwhile TFR-LRC can make higher fault tolerance under the same parameter settings by sacrificing a little bit of repair cost.