Hierarchical storage system, storage controller, and hierarchical control method

摘要

An object of the present invention is to enable efficient data movement between hierarchies. According to an embodiment, a storage controller of a hierarchical storage system specifies an access request from a host to access one or more logical blocks including a first logical block, and the first storage system includes: A logical block is included in a first logical extent, and the first logical extent belongs to an extent group including q logical extents to which q physical extents in the second storage device are allocated. If so, the data of the q physical extents are moved to free q physical extents in the storage apparatus positioned in the upper tier. [Selection] Figure 2