Description

An initiative data prefetching scheme is proposes on the storage servers in distributed file systems for cloud computing in this project. The client machines are not substantially involved in the process of data prefetching In this prefetching technique. but after analyzing the history of disk I/O access events the storage servers can directly prefetch the data, and then send the prefetched data to the relevant client machines proactively. To put this technique to work, the information about client nodes is piggybacked onto the real client I/O requests, and then forwarded to the relevant storage server. Then two prediction algorithm have been proposed in this project. This is to forecast future block access operations for directing what data should be fetched on storage servers in advance. Finally from the storage server, the prefetched data can be pushed to the relevant client machine from the storage server. Through this process the system can present the prefetching technique perfectly. It can benefit distributed file systems for cloud environments to achieve better I/O performance.