Research On The Snapshot Technology Of The RAID System

Snapshot technology is an effective solution to improve the system availability. Based on the analysis of the factors that influence the availability of RAID system, of which a number of implementation methods, system architecture are lucubrated as well as the snapshot technology. A prototype of RAID based snapshot backup system, which can significantly improve the system availability at the cost of acceptable performance, is designed and implemented.The first issue of designing the RAID snapshot system is the architecture of the RAID system. It is decided to implement the RAID snapshot system based on the RAID5 system. The most important part of the RAID snapshot system is the snapshot algorithm. Besides improving the system availability by the real-time snapshot backup, the Full Increment Snapshot algorithm includes a checkpoint snapshot backup and achieves the function of 2 backup in one snapshot disk by using the increment algorithm which can decreases the need of backup space.RAID snapshot system focuses on the system availability. System is ensured to run continuously by the rollback and recovery of data. The strategy of data recovery from single disk to multi disks introduced in this paper achieves the high efficiency of the system restoration.Finally the system architecture of RAID snapshot system is advanced by uniting the RAID technology and snapshot technology. Setting up a Markov model, we have compared the availability in theory and performance of test of RAID snapshot system with that of common RAID system. Taking into account of the factors above, we may reach the conclusion that RAID snapshot system has significant advantage against common RAID system in the applications which require high availability.