STORAGE SYSTEM INCLUDING MULTIPLE STORAGE APPARATUSES AND POOL VIRTUALIZATION METHOD

摘要

There are a plurality of storage apparatuses including a first storage apparatus and a second storage apparatus. The first storage apparatus has a virtual volume composed of a plurality of virtual segments. At least the second storage apparatus has a pool composed of a plurality of real pages (real storage areas). The plurality of storage apparatuses each manage one or more pools including at least the pool in the second storage apparatus as one virtual pool. The virtual pool is composed of a plurality of virtual pages, and each virtual page corresponds to any of the real pages. The first storage apparatus receives a write command that specifies an address belonging to an unallocated virtual segment to which no virtual page is allocated, allocates a free virtual page from the virtual pool to the unallocated virtual segment, and writes data accompanying the write command to the real page corresponding to the allocated virtual page.