Storage apparatus and its control method

摘要

Proposed are a storage apparatus and its control method capable of restoring data of a virtual page to an appropriate device hierarchy according to its data value. This storage apparatus stores, in a backup-destination storage medium, data stored in the respective physical pages allocated with the virtual volume and management information of the virtual volume including information concerning the device hierarchy to which the respective physical pages belong according to a backup command of the virtual volume, and allocates a physical page of the same device hierarchy as the device hierarchy of the physical page that was allocated before the backup to each of the restoration-target virtual pages of the virtual volume, respectively, and writes corresponding data, which was read from the storage medium, into each of the allocated physical pages according to a restoration command of the virtual volume and based on the management information of the virtual volume stored in the storage medium.

主权项

1. A storage apparatus configured to
provide a virtual volume to a host; allocate a storage area comprising a plurality of device hierarchies to the virtual volume in prescribed physical page units according to a data write request from the host for writing data into the virtual volume; and write write-target data into a first physical page of a first device hierarchy in the storage area, the storage apparatus comprising: an access pattern management unit configured to manage an access pattern from the host to the virtual volume for each virtual page of the virtual volume corresponding to the first physical page, wherein the access pattern of a virtual page comprises information concerning an average access count per second, a maximum value of the average access count, and a non-access period for the virtual page; a hierarchy control processing unit configured to change the first physical page to a second physical page belonging to another device hierarchy in the storage area for each of the virtual pages of the virtual volume based on the access pattern and as necessary, and migrate data stored in a pre-change physical page to a post-change physical page; a backup processing unit configured to store, in a backup-destination storage medium, data stored in the respective physical pages allocated with the virtual volume and management information of the virtual volume including information concerning the device hierarchy to which the respective physical pages belong according to a backup command of the virtual volume; and a restoration processing unit configured to allocate another physical page of the first device hierarchy to each restoration-target virtual pages of the virtual volume, respectively, and write corresponding data, which was read from the storage medium, into each of the allocated another physical pages according to a restoration command of the virtual volume and based on the management information of the virtual volume stored in the storage medium.