The Improved RAID 5 with the Disk Cache Using the Load-Balanced Destage Algorithm

摘要

Write requests are written from the disk cache to the disk array by the destage algorithm and the response time of host read request dominates the performance of the RAID 5. Since RAID is composed of multiple disk, the overal performance at the disk array level is more important than the performance at a disk level. However, previous destage algorithms do not take into consideration the overall performance of the disk array but the optimal performance at an each individual disk, and it may eventually decreases the RAID 5 performance. This paper proposes the load-balanced destage algorithm adopted in the RAID 5 at the disk array level, and shows that the proposed destage algorithm has higher performance than other previous destage algorithms