COMPUTER SYSTEM AND STORAGE CONTROL METHOD OF THE SAME

• US 20120023305A1
• Filed: 04/30/2010
• Published: 01/26/2012
• Est. Priority Date: 04/30/2010
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Satoyama, Ai, Eguchi, Yoshiaki
• Granted Patent: US 8,843,724 B2
• Time in Patent Office: Days
• US Class Current: 711/170
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• 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 3/0631 by allocating resources to storage systems
• CPC Class Codes: G06F 3/0638 Organizing or formatting or addressing of data
• CPC Class Codes: G06F 3/0644 Management of space entities, e.g. partitions, extents, pools
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• CPC Class Codes: G06F 3/0683 Plurality of storage devices
• CPC Class Codes: G06F 3/0685 Hybrid storage combining heterogeneous device types, e.g. hierarchical storage, hybrid arrays

Abstract

A computer system dynamically assigns the storage capacity from pool volumes to the access target in the higher-level system, and can immediately respond to the change of the status of the pool comprising the pool volumes. A control device sets the access target for the host computer to access, each time a write to the access target occurs from the host computer, from the pool assigned to the access target to the write area of the access target. The control device performs the processing of assigning the storage capacity from the logical volume in the pool. The control device defines the logical volumes in advance, compiles the same into a management group as a preliminary for the pool and, in accordance with the change of the pool status, adds the logical volumes from the management group to the pool.

Claims

1. A computer system comprising a control device for processing a write access from a host computer,

wherein the control device includes:

a first module for setting an access target to be accessed by the host computer,

a second module for setting a first pool having one or more logical volumes,

a third module for assigning a storage capacity from the logical volume of the first pool to a write destination area of the access target upon receiving a write request from the host computer [for writing into] the access target,

a fourth module for setting a second pool,

a fifth module for creating a logical volume from a storage resource and setting this as the second pool, and

a sixth module for determining a status of the first pool and, in accordance with the determination result, adding the logical volume from the second pool to the first pool.

2. The computer system according to claim 1,

wherein the access target is configured of a virtual volume in which a capacity provided by the host computer is virtualized, and

wherein the control device virtualizes a capacity of the first pool to the third module.

3. The computer system according to claim 2,

wherein the sixth module adds the logical volume from the second pool to the first pool upon determining that there is deficiency in the actual capacity that can be assigned to the access target of the first pool.

4. The computer system according to claim 2,

wherein the sixth module deletes the logical volume from the first pool and recovers the logical volume in the second pool upon determining that there is excess in the actual capacity that can be assigned to the access target of the first pool.

5. The computer system according to claim 3,

wherein the control device comprises a seventh module for setting a first threshold to the actual capacity of the first pool, and

wherein the sixth module determines deficiency in the actual capacity of the first pool based on the first threshold.

6. The computer system according to claim 2,

wherein the control device sets the first pool and the second pool so that they respectively comprise a plurality of hierarchies, and

wherein the sixth module migrates the logical volume between the first pool and the second pool between the same hierarchy upon adding the logical volume from the first pool to the second pool.

7. The computer system according to claim 1,

wherein the control device comprises an eighth module for setting a second threshold to the capacity of the second pool, and

wherein the sixth module determines excess or deficiency in the capacity of the second pool based on the second threshold, and adds the logical volume from the storage resource to the second pool upon determining deficiency in the capacity of the second pool.

8. The computer system according to claim 4,

wherein the second module sets a plurality of the first pools, and

wherein, upon determining that there is deficiency in the actual capacity of one first pool among the plurality of first pools and that there is excess in the actual capacity of the other first pools, the sixth module deletes the logical volume from the other first pools, recovers the logical volume in the second pool, and additionally adds the logical volume from the second pool to the one first pool.

9. The computer system according to claim 2,

wherein the control device sets a plurality of the virtual volumes, and

wherein the sixth module compares a third threshold based on a virtual capacity of the first pool and a total virtual capacity of the plurality of virtual volumes, and, if it is determined that the total virtual capacity exceeds the third threshold, determines whether to add a logical volume from the second pool to the first pool based on priority related to the third threshold.

10. The computer system according to claim 1,

wherein the access target is configured of a virtual volume in which a capacity provided by the host computer is virtualized,

wherein the control device:

virtualizes a capacity of the first pool to the third module, and comprises

a seventh module for setting a first threshold to the actual capacity of the first pool, and

an eighth module for setting a second threshold to a capacity of the second pool,

wherein the sixth module;

adds the logical volume from the second pool to the first pool upon determining deficiency in the actual capacity that can be assigned to the access target of the first pool based on the first threshold,

deletes the logical volume from the first pool and recovers the logical volume in the second pool upon determining excess in the actual capacity that can be assigned to the access target of the first pool, and

adds the logical volume from the storage resource to the second pool upon determining deficiency in the capacity of the second pool based on the second threshold and determining deficiency in the capacity of the second pool, and

wherein the control device sets the first pool and the second pool so that they respectively comprise a plurality of hierarchies, and

wherein the sixth module migrates the logical volume between the first pool and the second pool between the same hierarchy upon adding the logical volume from the first pool to the second pool.

11. The computer system according to claim 10,

wherein the second module sets a plurality of the first pools, and

wherein, upon determining that there is deficiency in the actual capacity of one first pool among the plurality of first pools and that there is excess in the actual capacity of the other first pools, the sixth module deletes the logical volume from the other first pools, recovers the logical volume in the second pool, and additionally adds the logical volume from the second pool to the one first pool.

12. The computer system according to claim 1,

wherein the third module determines whether the storage area of the write request has been assigned to the access target when there is a write request to the access target,

assigns a new storage area to the access target upon negating the determination, and

writing write data in the assigned storage area upon affirming [the determination].

13. The computer system according to claim 10,

wherein the fifth module creates the logical volume from a storage resource of an externally connected storage, and

wherein the sixth module examines the capacity of the first pool, and, if there is deficiency in the capacity, adds the storage capacity of the externally connected storage to the first pool.

14. The computer system according to claim 10,

wherein the second module sets a plurality of the first pools, and

wherein, upon determining that there is deficiency in the actual capacity of one first pool among the plurality of first pools and that there is excess in the actual capacity of the other first pools, the sixth module deletes the logical volume from the other first pools, and additionally adds the logical volume from the second pool to the one first pool without recovering the logical volume in the second pool.

15. A storage control method of a computer system comprising a control device that controls access from a host computer and thereby controls read/write processing to a storage resource,

wherein the control device:

sets an access target to be accessed by the host computer,

executes processing of assigning, from a pool assigned to the access target to a write area of the access target, a storage capacity from a logical volume in the pool upon receiving a write [request] from the host computer [for writing into] the access target,

defines other logical volumes in advance and summarizes them in a management group as backup for the pool, and

adds the other logical volumes from the management group to the pool based on changes in a status of the pool.