RAID-RMS: A fault tolerant stripped mirroring RAID architecture for distributed systems

Disk arrays, or RAIDs, have become the solution to increase the capacity, bandwidth and reliability of most storage systems. In spite of its high redundancy level, disk mirroring is a popular RAID paradigm, because replicating data also doubles the bandwidth available for processing read requests, improves the reliability and achieves fault tolerance. In this paper, we present a new RAID architecture called RAID-RMS in which a special hybrid mechanism is used to map the data blocks to the cluster. The main idea behind the proposed algorithm is to combine the data block striping and disk mirroring technique with a data block rotation. The resulting architecture improves the parallelism reliability and efficiency of the RAID array. We show that the proposed architecture is able to serve many more disk requests compared to the other mirroring-based architectures. We also argue that a more balanced disk load is attained by the given architecture, especially when there are some disk failures.