Disk array controller, its disk array control unit, and increase method of the unit

• US 6,519,680 B2
• Filed: 09/05/2002
• Issued: 02/11/2003
• Est. Priority Date: 03/10/2000
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Fujibayashi, Akira, Fujimoto, Kazuhisa, Sakurai, Wataru, Kanai, Hiroki
• Primary Examiner(s): Nguyen, Hiep T.
• Application Number:
  US10/234,471
• Publication Number:
  US 20030005221A1
• Time in Patent Office: 159 Days
• Field of Search: 711/114, 711/113, 711/148, 710/313, 710/316
• US Class Current: 711/114
• CPC Class Codes: G06F 12/0866 for peripheral storage systems, e.g. disk cache
• CPC Class Codes: G06F 3/0607 by facilitating the process of upgrading existing storage systems, e.g. for improving compatibility between host and storage device
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0613 in relation to throughput
• CPC Class Codes: G06F 3/0635 by changing the path, e.g. traffic rerouting, path reconfiguration
• CPC Class Codes: G06F 3/0658 Controller construction arrangements
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 3/0683 Plurality of storage devices
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

A disk array controller is made up of multiple disk array control units for implementing the data read/write operation and each having channel IF units, disk IF units, cache memory units and shared memory units. The disk array controller further includes inter connections for interconnecting the shared memory units and interconnecting the cache memory units across the border of disk array control units. Thereby alleviating the deterioration of performance due to the data transfer between the disk array control units, when the multiple disk array control units are to be operated as a single disk array controller.

Claims

1. A disk array controller comprising:

a plurality of disk array control units, each having one or more channel interface units for interfacing with a host computer;

one or more disk interface units for interfacing with disk drives;

a cache memory unit for temporarily storing data which is written to or read out of said disk drives; and

a shared memory unit for storing control information of data transfer between said channel interface unit and disk interface unit and said cache memory unit and control information for said disk drives,

said disk array control unit implementing the data read/write operation in response to a data read/write request from said host computer by operating on said channel interface unit to transfer data between said interface with said host computer and said cache memory unit and operating on said disk interface unit to transfer data between said disk drive and said cache memory unit,

said channel interface units and disk interface units and said cache memory units in said disk array control units having their connection nodes interconnected through a first interconnection across the border of disk array control units,

said channel interface units and disk interface units and said shared memory units in said disk array control units having their connection nodes interconnected through a second interconnection across the border of disk array control units.