PITR: An Efficient Single-Failure Recovery Scheme for PIT-Coded Cloud Storage Systems

In cloud storage systems, the use of erasure coding results in high read latency and long recovery time when drive or node failure happens. In this paper, we design a parity independent array codes (PIT), a variation of STAR code, which is triple fault tolerant and nearly space-optimal, and also propose an efficient single-failure recovery scheme (PITR) for them to mitigate the problem. In addition, we present a "shortened" version of PIT (SPIT) to further reduce the recovery cost. In this way, less disk I/O and network resources are used, thereby reducing the recovery time and achieving a high system reliability and availability.