摘要 |
<p>An exemplary storage susytem of the invention processes requests to access a primary volume and a plurality of secondary volumes forming pairs with the primary volume. In each of the plurality of secondary volumes, address areas are defined which are respectively associated with address areas of the primary volume. Each of the plurality of secondary volumes stores differential data with respect to data in the primary volume. A controller monitors write accesses to the primary volume and the plurality of secondary volumes, and retains a monitoring result. The controller controls, based on, in the monitoring result, presence/absence of past write accesses to a plurality of areas in the primary volume and areas respectively corresponding to the plurality of areas in the plurality of secondary volumes, accesses to the primary volume.</p> |