Patent ID: 8725971
Filing Date: 2014-05-13
Classification: G06F

Abstract:
1. A storage apparatus, comprising: one or more storage devices configured to provide storage areas; and a controller configured to create a logical volume in the storage area provided by the one or more storage devices and to read and write data from/to the logical volume according to a request from a host, wherein the controller is configured to acquire one or more snapshots which are data images at certain time points of the logical volume, wherein the controller is configured to determine whether one of the following conditions is met: a performance value of the one or more snapshots exceeds a performance value of the logical volume; or the performance value of the logical volume is below a predetermined threshold, wherein, when one of the conditions is met, the controller is configured to execute predetermined control processing according to usage cases of the snapshots; wherein the controller is configured to determine whether the usage case is a usage case in which an access range of the one or more snapshots is localized data or a usage case in which the access range is all data; wherein the controller is configured to determine whether the logical volume is a usage case of a volume with a higher priority ranking than the one or more snapshots; wherein the controller is configured to execute capacity limits for a cache memory when the usage case is a usage case where the access range of the one or more snapshots is all data and there is parity between the logical volume and the one or more snapshots.