STORAGE APPARATUS COMPRISING SNAPSHOT FUNCTION, AND STORAGE CONTROL METHOD

摘要

Storage apparatus, in response to write command specifying write destination with regards to multiple virtual areas, allocates a free real area of multiple real areas based on storage devices to a write-destination virtual area, of the multiple virtual areas, to which the write destination belongs, and writes write-target data conforming to the write command to the allocated real area. The storage apparatus, where a first write command has been received subsequent to a snapshot acquisition time point, erases an allocation of a first real area to a first virtual area to which the write destination specified in the first write command belongs, allocates the first real area to a free second virtual area to which a real area has not been allocated, allocates a free second real area to the first virtual area, writes write-target data conforming to the first write command to the second real area.