A Cost-Based Heterogeneous Recovery Scheme for Distributed Storage Systems With RAID-6 Codes

Modern distributed storage systems provide large-scale, fault-tolerant data storage. To reduce the probability of data unavailability, it is important to recover the lost data of any failed storage node efficiently. In practice, storage nodes are of heterogeneous types and have different transmission bandwidths. Thus, traditional recovery solutions that simply minimize the number of data blocks being read may no longer be optimal in a heterogeneous environment. The authors propose a Cost-based Heterogeneous Recovery (CHR) algorithm for RAID- 6-coded storage systems. They formulate the recovery problem as an optimization model in which storage nodes are associated with generic costs.