Incorporate Proactive Data Protection In Zfs Towards Reliable Storage Systems

Disk drive failure related data lost remains a major threat to storage system reliability. Current counter-measurement all focused on reactive data protection, such as using RAID or erasure coding to reconstruct data after failure occurs. However, we argue that post-failure recovery will not scalable when the storage demand keep increase. In this paper, we present a proactive data protection (PDP) framework within the ZFS file system to rescue data from disks before actual failure onset. By reducing the risk of data loss and mitigating the prolonged disk rebuilds caused by disk failures, PDP is designed to enhance the overall storage reliability. We extensively evaluate the recovery performance of ZFS with diverse configurations, and further explore disk failure prediction techniques to develop a proactive data protection mechanism in ZFS. We further compare the performance of different data protection strategies, including post-failure disk recovery, proactive disk cloning, and proactive data recovery. We propose an analytic model that uses storage utilization and contextual system information to select the best data protection strategy that can save up to 70% of data rescue time..