Data reallocation among storage systems

• US 7,953,949 B2
• Filed: 07/17/2007
• Issued: 05/31/2011
• Est. Priority Date: 07/06/2000
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Mogi, Kazuhiko, Arakawa, Hiroshi, Eguchi, Yoshiaki, Arai, Kouji
• Primary Examiner(s): Ellis; Kevin L
• Assistant Examiner(s): Namazi; Mehdi
• Application Number:
  US11/879,548
• Publication Number:
  US 20070266216A1
• Time in Patent Office: 1,414 Days
• Field of Search: 711/114, 711/154, 711/161, 711/165, 707/10, 707/204, 707/999.01, 707/999.204
• US Class Current: 711/165
• CPC Class Codes: G06F 11/1096 Parity calculation or recalculation after configuration or reconfiguration of the system
• CPC Class Codes: G06F 11/2087 with a common controller
• CPC Class Codes: G06F 12/0866 for peripheral storage systems, e.g. disk cache
• CPC Class Codes: G06F 3/0605 by facilitating the interaction with a user or administrator
• CPC Class Codes: G06F 3/0608 Saving storage space on storage systems
• CPC Class Codes: G06F 3/0613 in relation to throughput
• CPC Class Codes: G06F 3/0631 by allocating resources to storage systems
• CPC Class Codes: G06F 3/0635 by changing the path, e.g. traffic rerouting, path reconfiguration
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/0659 Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: H04L 61/457 containing identifiers of data entities on a computer, e.g. file names
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

The present invention provides techniques, including a method and system, for relocating data between storage systems. In one embodiment of the present invention a host collects usage information from a plurality of storage systems, and determines the relocation destination LU for data stored in the LU to be relocated. The host alters an LU logical position name table that determines matching between the logical position names of data and LUs. It also carries out data relocation between storage subsystems by shifting data stored in an origin LU to be relocated to a destination LU. In another embodiment relocation of files is provided.

Claims

1. A computer system comprising:

a first storage system providing a first logical unit;

a second storage system coupled to the first storage system, providing a second logical unit; and

a computer coupled to the first and the second storage systems, including an application and I/O management module, in which the I/O management module is configured to manage mapping relation between a logical position recognized by the application and identifiers of the first logical unit in the first storage system and the second logical unit in the second storage system;

wherein at least one of the first and the second storage systems migrates data stored in the first logical unit of the first storage system to the second logical unit of the second storage system as to be consistent with the first logical unit in the first storage system, wherein the I/O management module changes the mapping relation as to correlate the logical position recognized by the application with the second logical unit in the second storage system from the first logical unit in the first storage system, based on notification from at least one of the first and the second storage systems, and controls access to the logical position from the application by issuing I/O request to the second logical unit in the second storage system instead of the first logical unit in the first storage system.

2. A computer system according to claim 1:

wherein the computer sends a migration instruction to the second storage system to migrate data stored in the first logical unit from the first storage system;

wherein the second storage system starts migration processing and notifies the computer of the receipt of the migration instruction.

3. A computer system according to claim 1, wherein the computer calculates usage information for each of the first and the second logical units, and determines the first logical unit to be migrated based on the usage information.

4. A computer system according to claim 3, wherein the usage information includes at least one of duration of random read processing, duration of random write processing, duration of sequential read processing, and duration of sequential write processing.

5. A computer system according to claim 3, the computer specifies the second logical unit as a destination logical unit in order to satisfy a request condition regarding at least one of performance and reliability of the destination logical unit.

6. A computer system according to claim 2, wherein the migration processing is executed on a basis of file stored in the first logical unit.

7. A computer system according to claim 1, wherein the computer manages the first and the second logical units as integrated logical area.