Abstract: A RAID controller accesses an access request area on logical volumes distributed and stored on a plurality of physical disks according to a disk access request from a host. The controller has a plurality of management modules which are in-charge of plurality of the redundant groups respectively and issuing a logical format request for each area of said logical volume by referring to a management table for managing progress information of the logical format processing. Each management module has a plurality of the management table for being in-charge of said plurality of redundant groups and a queue for queuing the disk access request. The management module, according to the disk access request, judges whether all the access request areas have been logically formatted referring to the management table.

Abstract: An input/output control apparatus controls input/output requests from a host unit to a plurality of subordinate unit. A priority order managing section in the input/output control apparatus controls a priority order of the input/output requests based on priority orders of the input/output requests given by the host unit, for each of the subordinate units.

Abstract: A storage controller executes logical format to enable host access to a physical disk, where the logical format of a physical disk is executed without waiting for host access. The storage controller comprises a logical format management module having bit map memory for managing progress information on format processing of a logical volume, and a lower layer module which accesses a physical disk according to the request of the management module. The management module judges whether all the access areas have been formatted referring to the bit map memory, requests the disk access to the lower layer module if judged as formatted, while, issues a logical format processing request before the disk access, queues the disk access request to the queue if not formatted, further searches the unformatted area from the bit map memory, and issues a logical format processing request if no disk access request exists in the queue.

Abstract: A RAID controller accesses an access request area on logical volumes distributed and stored on a plurality of physical disks according to a disk access request from a host. The controller has a plurality of management modules which are in-charge of plurality of the redundant groups respectively and issuing a logical format request for each area of said logical volume by referring to a management table for managing progress information of the logical format processing. Each management module has a plurality of the management table for being in-charge of said plurality of redundant groups and a queue for queuing the disk access request. The management module, according to the disk access request, judges whether all the access request areas have been logically formatted referring to the management table.

Abstract: A storage controller executes logical format to enable host access to a physical disk, where the logical format of a physical disk is executed without waiting for host access. The storage controller comprises a logical format management module having bit map memory for managing progress information on format processing of a logical volume, and a lower layer module which accesses a physical disk according to the request of the management module. The management module judges whether all the access areas have been formatted referring to the bit map memory, requests the disk access to the lower layer module if judged as formatted, while, issues a logical format processing request before the disk access, queues the disk access request to the queue if not formatted, further searches the unformatted area from the bit map memory, and issues a logical format processing request if no disk access request exists in the queue.

Abstract: An input/output control apparatus controls input/output requests from a host unit to a plurality of subordinate unit. A priority order managing section in the input/output control apparatus controls a priority order of the input/output requests based on priority orders of the input/output requests given by the host unit, for each of the subordinate units.