A method for enhancing the snapshot performance in SAN volume manager

Linux-based storage clustering software, SANtopia Volume Manager (SVM), has provided various online volume management features to support enterprise computing in SAN environment in which a number of storages and host computers are connected with each other through fiber channel. The online snapshot is one of the representative features provided by SVM and enables online backup of data without system downtime. In this paper, we propose an advanced online snapshot technique to enhance the overall system performance. The SVM has taken relatively long time according to the size of the logical volume in performing a snapshot creation or deletion operation. Additionally it consumed more time to perform a normal I/O operation on the original data with snapshot than without snapshot. In order to solve the problems described above, we update the metadata structure of SVM and enhance the performance by reducing the execution time of snapshot creation, snapshot deletion, and normal I/O operation with snapshot. Also, we can provide confidence of system by ensuring that all I/O operations have same performance regardless of existence of snapshot.