Virtual disk snapshot is a prevailing technology to support virtual machine failover. It's usually organized into linked structure, which may cause virtual machine performance degradation because this method would introduce additional disk I/O overhead. In this paper, we analyze the efficiency of disk snapshot technology with non-linked structure. By integrating ZFS and OCFS2 file system based on non-linked structure, we implement an efficient management system for virtual machine snapshots. In order to improve the efficiency of snapshot retrieval, we also propose a virtual machine snapshot storage organization model and optimize a snapshot search algorithm. The result of comparative experiment indicates our system's effectiveness.