Patent ID: 8745354

Claim:
A computer system, comprising: one or ore storage apparatuses; and one or more host computers coupled to the one or more storage apparatuses, each of the one or more host computers comprising: a first interface coupled to the one or more storage apparatuses; a first processor coupled to the first interface; and a first storage device coupled to the first processor, the first processor being configured to control one or more virtual machines each configured to execute one or more application programs, wherein each of the one or more storage apparatuses comprises: a controller coupled to the one or more host computers; and one or more physical storage devices coupled to the controller, the each of the one or more storage apparatuses being configured to hold information associating a plurality of virtual volumes and a plurality of pools each including real storage areas of the one or more physical storage devices, wherein when a request to write data designating one of the plurality of virtual volumes as a volume of a write destination is received from the one or more host computers, the each of the one or more storage apparatuses is configured to allocate, to the virtual volume of the write destination, the real storage areas included in each of the plurality of pools corresponding to the virtual volume of the write destination, and to store the data in the allocated real storage areas, wherein the computer system is configured to: determine, based on the information held by the each of the one or more storage apparatuses, orders of priority of the volumes of the write destination by the one or more host computers; and hold the determined orders of priority, wherein the each of the one or more storage apparatuses is configured to hold information indicating amounts of the real storage areas not yet allocated to the plurality of virtual volumes of the real storage areas included in the each of the plurality of pools, and wherein the computer system is configured to determine the orders of priority based on the amounts of the real storage areas not yet allocated to the plurality of virtual volumes.