Patent ID: 8375167
Filing Date: 2013-02-12
Classification: G06F

Abstract:
1. A storage system comprising: a storage pool for at least a logical volume having a plurality of slices to store data; a memory to store a slice table indicating whether each slices of the logical volume is assigned from the storage pool or not; and a controller to execute a procedure, the procedure including: receiving a write request from a host, generating a slice in the logical volume by assigning a part of the storage pool according to the received write request, updating the slice table in the memory when the slice corresponding to the received write request is not assigned from the storage pool in reference to the slice table, writing data into at least one of the slices according to the received write request, receiving a release command for releasing one of the slices, sending out a response indicating releasing of one of the slices corresponding to the release command has completed regardless of an execution of processing corresponding to the release command, duplicating a part of the slice corresponding to the release command into a copy target volume, and releasing the one of the slices corresponding to the release command upon completely duplicating the part of the slice corresponding to the release command into the copy target volume.