基于备份的RAID5在线重构框架

The on-line reconstruction framework of RAID5 based on backup

为解决国内外现有RAID5在线重构研究一直未解决的重负载持续访问下RAID5重构性能急剧恶化的问题，提出了利用外部存放的备份数据来加速RAID5在线重构的思想，构建了基于备份的RAID5在线重构框架。此框架利用备份系统所提供的恢复带宽将处于最近一次备份时间点的版本数据整合至spare盘，然后利用RAID5所提供的重构带宽将自最近一次备份时间点之后的已修改数据重构至spare盘。测试结果表明，该框架相对于现有重构方法显著改善了RAID5的重构性能和服务性能。

To solve the unsolved problem in present research on RAID5 reconstruction that the reconstruction periormance of RAID5 deteriorates rapidly under the continuous heavy workload, this thesis proposes the idea of accelerating the on-line reconstruction of RAID5 by use of the backup data in external storages, and completes the on-line reconstruction framework of RAID5 based on backup. The framework utilizes the restored bandwidth provided by the backup system for integrating the version data at the latest backup time point into the spare disk, and then utilizes the reconstruction bandwidth provided by RAID5 for reconstructing the modified data after the latest backup time point to the spare disk. The test result shows that compared with the existing reconstruction methods, the framework greatly improves the reconstruction performance and service performance of RAIDS.