Storage system having a thin provisioning function

• US 9,256,524 B2
• Filed: 12/21/2012
• Issued: 02/09/2016
• Est. Priority Date: 08/17/2001
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Kano, Yoshiki, Yamamoto, Akira
• Primary Examiner(s): Rones, Charles
• Assistant Examiner(s): Li, Sidney
• Application Number:
  US13/723,648
• Publication Number:
  US 20130117523A1
• Time in Patent Office: 1,145 Days
• Field of Search: 711/112, 711/162
• US Class Current: 1/1
• CPC Class Codes: G06F 11/2087 with a common controller
• CPC Class Codes: G06F 12/02 Addressing or allocation; Relocation program address sequencing G06F9/00; arrangements for selecting an address in a digital store G11C8/00
• CPC Class Codes: G06F 12/0223 User address space allocation, e.g. contiguous or non contiguous base addressing
• 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 3/0631 by allocating resources to storage systems
• 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 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

A storage system, coupled to an external storage system, manages a virtual volume, such as a thin provision volume. The storage system also manages a first logical device created by using storage area of internal storage devices and a second logical device created by using storage area of external storage devices in the external storage system. A storage area in the first logical device or the second logical device is allocated to the virtual volume after receiving a write request to the virtual volume. The storage system has advantage that a storage area in the first logical device and the second logical device can be managed uniformly in thin provisioning function of the storage system.

Claims

1. A storage system coupled to an external storage system, the external storage system including a plurality of external storage devices on which one or more external logical volumes is created, the storage system comprising:

a plurality of internal storage devices; and

a controller being configured to manage a plurality of virtual volumes, and manage one or more first logical devices, in the storage system, corresponding to the plurality of internal storage devices and one or more second logical devices, in the storage system, corresponding to the one or more external logical volumes,

the controller further being configured to;

manage a plurality of first storage segments in the first logical devices as unallocated storage segments to at least a first virtual volume of the plurality of virtual volumes and manage a plurality of second storage segments in the second logical devices as unallocated storage segments to at least a second virtual volume of the plurality of virtual volumes, where each of the plurality of first storage segments and each of the plurality of second storage segments has the same size,

allocate, after receiving a first write request to the first virtual volume of the plurality of virtual volumes, a first storage segment of the plurality of first storage segments in the first logical devices to the first virtual volume, and store data corresponding to the first write request to the allocated first storage segment, and

allocate, after receiving a second write request to the second virtual volume of the plurality of virtual volumes, a second storage segment of the plurality of second storage segments in the second logical devices to the second virtual volume, and send data corresponding to the second write request to the external storage system.

2. A storage system according to claim 1,

wherein each of the plurality of first storage segments and each of the plurality of second storage segments is a unit for allocating to the plurality of virtual volumes.

3. A storage system according to claim 1,

wherein the controller is configured to manage a storage pool including the plurality of first storage segments and the plurality of second storage segments.

4. A storage system according to claim 1,

wherein one of the second logical devices is created by using storage areas of the one or more external logical volumes.

5. A storage system coupled to an external storage system, the external storage system including a plurality of external storage devices on which one or more external logical volumes is created, the storage system comprising:

a plurality of internal storage devices; and

a controller being configured to;

manage a storage pool including one or more first logical devices, in the storage system, corresponding to the plurality of internal storage devices and one or more second logical devices, in the storage system, corresponding to the one or more external logical volumes;

manage a first storage area of the first logical devices and a second storage area of the second logical devices as unallocated storage areas to a plurality of virtual devices which include a first virtual device and a second virtual device, where each of the first storage area and the second storage area has the same size;

provide the first virtual device to which the first storage area of the first logical devices is allocated from the storage pool after receiving a first write request to the first virtual device to store data corresponding to the first write request; and

provide the second virtual device to which the second storage area of the second logical devices is allocated from the storage pool after receiving a second write request to the second virtual device to send data corresponding to the second write request to the external storage system.

6. A storage system according to claim 5,

wherein each of the first storage area and each of the second storage area is a unit for allocating to the plurality of virtual devices.

7. A storage system according to claim 5,

wherein one of the second logical devices is created by using storage areas of the one or more external logical volumes.

8. A storage system coupled to an external storage system, the external storage system including a plurality of external storage devices on which one or more external logical volumes is created, the storage system comprising:

a plurality of internal storage devices; and

a controller being configured to;

manage a storage pool including a plurality of first storage segments of one or more first logical devices, in the storage system, corresponding to the plurality of internal storage devices and a plurality of second storage segments of one or more second logical devices, in the storage system, corresponding to the external logical volumes;

manage at least one first storage segment of the first logical devices and at least one second storage segment of the second logical devices as unallocated storage segments to a plurality of virtual devices which include a first virtual device and a second virtual device, where each of the first storage segment and the second storage segment has the same size;

provide the first virtual device to which the at least one first storage segment of the first logical devices is allocated from the storage pool after receiving a first write request to the first virtual device to store data corresponding to the first write request;

and provide the second virtual device to which the at least one second storage segment of the second logical devices is allocated from the storage pool after receiving a second write request to the second virtual device to send data corresponding to the second write request to the external storage system.

9. A storage system according to claim 8,

wherein each of the plurality of the first storage segments and each of the plurality of the second storage segments is a unit for allocating to the plurality of virtual devices.

10. A storage system according to claim 8,

wherein one of the second logical devices is created by using storage areas of the one or more of external logical volumes.

11. A first storage system coupled to a second storage system, the second storage system including a plurality of second storage devices on which one or more second logical volumes is created, the first storage system comprising:

a plurality of first storage devices; and

a controller being configured to manage a plurality of virtual volumes, and manage one or more first logical devices, in the first storage system, corresponding to the plurality of first storage devices and one or more second logical devices, in the first storage system, corresponding to the one or more second logical volumes,

the controller further being configured to;

manage a plurality of first storage segments in the first logical devices and a plurality of second storage segments in the second logical devices, where each of the plurality of first storage segments and each of the plurality of second storage segments has the same size,

allocate, after receiving a first write request to a first virtual volume of the plurality of virtual volumes, a first storage segment of the plurality of first storage segments in the first logical devices to the first virtual volume, and store data corresponding to the first write request to the allocated first storage segment, and

allocate, after receiving a second write request to a second virtual volume of the plurality of virtual volumes, a second storage segment of the plurality of second storage segments in the second logical devices to the second virtual volume, and send data corresponding to the second write request to the second storage system.

12. A first storage system according to claim 11,

wherein each of the plurality of first storage segments and each of the plurality of second storage segments is a unit for allocating to the plurality of virtual volumes.

13. A first storage system according to claim 11,

wherein the controller is configured to manage a storage pool including the plurality of first storage segments and the plurality of second storage segments.

14. A first storage system according to claim 11,

wherein one of the second logical devices is created by using storage areas of the one or more second logical volumes.

15. A first storage system coupled to a second storage system, the second storage system including a plurality of second storage devices on which one or more second logical volumes is created, the storage system comprising:

a plurality of first storage devices; and

a controller being configured to;

manage a storage pool including one or more first logical devices, in the first storage system, corresponding to the plurality of first storage devices and one or more second logical devices, in the first storage system, corresponding to the one or more second logical volumes;

manage a first storage area of the first logical devices and a second storage area of the second logical devices as unallocated storage areas to a plurality of virtual devices which include a first virtual device and a second virtual device, where each of the first storage area and the second storage area has the same size;

provide the first virtual device to which the first storage area of the first logical devices is allocated from the storage pool after receiving a first write request to the first virtual device to store data corresponding to the first write request;

and provide the second virtual device to which the second storage area of the second logical devices is allocated from the storage pool after receiving a second write request to the second virtual device to send data corresponding to the second write request to the second storage system.

16. A first storage system according to claim 15,

wherein each of the first storage area and each of the second storage area is a unit for allocating to the plurality of virtual devices.

17. A first storage system according to claim 15,

wherein one of the second logical devices is created by using storage areas of the one or more second logical volumes.

18. A first storage system coupled to a second storage system, the second storage system including a plurality of second storage devices on which one or more second logical volumes is created, the first storage system comprising:

a plurality of first storage devices; and

a controller being configured to manage a first virtual volume including a plurality of first virtual storage areas and a second virtual volume including a plurality of second virtual storage areas and manage one or more first logical devices, in the first storage system, corresponding to the plurality of first storage devices and one or more second logical devices, in the first storage system, corresponding to the one or more second logical volumes,

the controller further being configured to;

manage a plurality of first storage areas in the first logical devices and a plurality of second storage areas in the second logical devices, where each of the plurality of first storage areas and each of the plurality of second storage areas has the same size,

allocate, after receiving a first write request to at least one first virtual storage area of the first virtual volume, at least one first storage area of the plurality of first storage areas in the first logical devices to the at least one first virtual storage area of the first virtual volume, and store data corresponding to the first write request to the allocated at least one first storage area, and

allocate, after receiving a second write request to at least one second virtual storage area of the second virtual volume, at least one second storage area of the plurality of second storage areas in the second logical devices to the at least one second virtual storage area of the second virtual volume, and send data corresponding to the second write request to the second storage system.

19. A first storage system according to claim 18,

wherein each of the plurality of first storage areas and each of the plurality of second storage areas is a unit for allocating to the first plurality of virtual storage areas of the first virtual volume and the second plurality of virtual storage areas of the second virtual volume.

20. A first storage system according to claim 18,

wherein the controller is configured to manage a storage pool including the plurality of first storage areas and the plurality of second storage areas.

21. A first storage system according to claim 18,

wherein one of the second logical devices is created by using storage areas of the one or more second logical volumes.

22. A method for a first storage system coupled to a second storage system, the method comprising:

managing a plurality of virtual volumes;

managing one or more first logical devices, in the first storage system, corresponding to a plurality of first storage devices in the first storage system and one or more second logical devices, in the first storage system, corresponding to a plurality of second logical volumes which are provided by the second storage system;

managing a plurality of first storage segments in the first logical devices and a plurality of second storage segments in the second logical devices, where each of the plurality of first storage segments and each of the plurality of second storage segments has the same size;

allocating, after receiving a first write request to a first virtual volume of the plurality of virtual volumes, a first storage segment of the plurality of first storage segments in the first logical devices to the first virtual volume;

storing data corresponding to the first write request to the allocated first storage segment,

allocating, after receiving a second write request to a second virtual volume of the plurality of virtual volumes, a second storage segment of the plurality of second storage segments in the second logical devices to the second virtual volume; and

sending data corresponding to the second write request to the second storage system.

23. A method according to claim 22,

wherein each of the plurality of first storage segments and each of the plurality of second storage segments is a unit for allocating to the plurality of virtual volumes.

24. A method according to claim 22 further comprising,

managing a storage pool including the plurality of first storage segments and the plurality of second storage segments.

25. A method according to claim 22,

wherein one of the second logical devices is created by using storage areas of the plurality of second logical volumes.

26. A method for a first storage system coupled to a second storage system, the method comprising:

managing a first virtual volume including a plurality of first virtual storage areas and a second virtual volume including a plurality of second virtual storage areas;

managing one or more first logical devices, in the first storage system, corresponding to a plurality of first storage devices and one or more second logical devices, in the first storage system, corresponding to a plurality of second logical volumes provided by the second storage system;

managing a plurality of first storage areas in the first logical devices and a plurality of second storage areas in the second logical devices, where each of the plurality of first storage areas and each of the plurality of second storage areas has the same size; and

allocating, after receiving a first write request to at least one first virtual storage area of the first virtual volume, at least one first storage area of the plurality of first storage areas in the first logical devices to the at least one first virtual storage area of the first virtual volume;

storing data corresponding to the first write request to the allocated at least one first storage area,

allocating, after receiving a second write request to at least one second virtual storage area of the second virtual volume, at least one second storage area of the plurality of second storage areas in the second logical devices to the at least one second virtual storage area of the second virtual volume; and

sending data corresponding to the second write request to the second storage system.

27. A method according to claim 26,

wherein each of the plurality of first storage areas and each of the plurality of second storage areas is a unit for allocating to the plurality of first virtual storage areas of the first virtual volume and the plurality of second virtual storage areas of the second virtual volume.

28. A method according to claim 26 further comprising,

managing a storage pool including the plurality of first storage areas and the plurality of second storage areas.

29. A method according to claim 26, wherein one of the second logical devices is created by using storage areas of the plurality of second logical volumes.