STORAGE DEVICE AND STORAGE CONTROL METHOD

摘要

This storage device includes a pool containing multiple pool pages, and a controller. The controller: includes virtual page management information in which multiple virtual pages and the multiple pool pages are associated with each other; retains the virtual page management information based on a first moment when a snapshot of a virtual volume at the first moment is created; and, in response to a write request received after the first moment, associates a virtual page specified by the received write request with a new available pool page and writes the received write request data in the new available pool page when the virtual page is already associated with a pool page in the virtual page management information based on the first moment.