Volume management apparatus, volume management method, and volume management program

A volume management method of a volume management apparatus which stores a plurality of volumes and performs an input/output (I/O) process on the volumes, wherein the volumes include a first volume and a second volume which is a volume copied from the first volume by a snapshot,

• the method, comprising:
• determining whether, in a case where a write request is received, a target volume of the write request is a volume of which a storage region is a valid region to which a data amount reduction process is applied;
• and
• depending on a case where a target volume of the write request is a volume of which the storage region is the valid region or a case where the target volume of the write request is a volume of which the storage region is not the valid region, from a plurality of processes of creating the second volume related to the snapshot, selecting a method of creating a process and performing the selected method.

A non-transitory computer readable storage medium storing thereon a volume management program which is executed by a computer which forms a volume management apparatus which stores a plurality of volumes and performs an input/output (I/O) process on the volumes,

• wherein the volumes include a first volume and a second volume which is a volume copied from the first volume by a snapshot,
• the program, when executed by the computer, causes the computer to perform:
• determining whether, in a case where a write request is received, a target volume of the write request is a volume of which a storage region is a valid region for which a data amount reduction process is applied;
• and
• depending on a case where a target volume of the write request is a volume of which the storage region is the valid region or a case where the target volume of the write request is a volume of which the storage region is not the valid region, from a plurality of processes of creating the second volume related to the snapshot, selecting a method of creating a process and performing the selected method.