Optimized Shrinking of Virtual Disks

• US 20120239896A1
• Filed: 03/15/2011
• Published: 09/20/2012
• Est. Priority Date: 03/15/2011
• Status: Active Grant

• Current Assignee: CA, Inc. (d/b/a CA Technologies) (Broadcom, Inc.)
• Original Assignee: Symantec Corporation (NortonLifeLock Inc.)
• Inventors: Sobel, William E.
• Granted Patent: US 8,904,136 B2
• Time in Patent Office: Days
• US Class Current: 711/165
• CPC Class Codes: G06F 3/0608 Saving storage space on storage systems
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0644 Management of space entities, e.g. partitions, extents, pools
• CPC Class Codes: G06F 3/0664 at device level, e.g. emulation of a storage device or system

Abstract

Various systems and methods shrinking a storage object. For example, one method can involve receiving a request to shrink the storage object. The storage object can comprise multiple storage locations. The method can also involve receiving a list that identifies a set of the storage locations. The list can be generated in response to the request to shrink the storage object. The method can also involve reading data from a set of storage locations in the storage object that are not identified in the received list and copying the read data from the first storage object to a second storage object.

Claims

1. A method comprising:

receiving a request to perform a shrink operation on a first storage object, wherein the first storage object comprises a plurality of storage locations;

receiving a first list that identifies a first set of storage locations, wherein

the first set of storage locations is a first subset of the plurality of storage locations, and

the list is received in response to the request to perform a shrink operation;

reading data from a second set of storage locations, wherein

the second set of storage locations is a second subset of the plurality of storage locations, and

the first set of storage locations and second set of storage locations are mutually exclusive; and

copying the data to a second storage object.

2. The method of claim 1, wherein

the first storage object and second storage object comprise dynamic virtual disks.

3. The method of claim 1, wherein

the first set of storage locations identifies portions of a first file, and

the first file is created by a virtual machine in response to the request.

4. The method of claim 3, further comprising:

detecting completion of the shrink operation; and

deleting the file in response to the detecting.

5. The method of claim 1, wherein

the first set of storage locations corresponds to unused portions of the first storage object.

6. The method of claim 1, further comprising:

receiving a second list, wherein the first list corresponds to unused portions of a first partition of the first storage object and the second list corresponds to unused portions of a second partition of the first storage object; and

merging the second list with the first list.

7. The method of claim 1, further comprising:

detecting an attribute of the file, wherein the attribute indicates that creating the file does not require any input/output (I/O) operations.

8. The method of claim 1, further comprising:

allocating an amount of storage space for the second storage object in response to receiving the request, wherein

the amount of storage space equals a first amount of storage space allocated to the first storage object.

9. A computer readable storage medium storing program instructions executable to:

receive a request to perform a shrink operation on a first storage object, wherein the first storage object comprises a plurality of storage locations;

receive a first list that identifies a first set of storage locations, wherein

the first set of storage locations is a first subset of the plurality of storage locations, and

the list is received in response to the request to perform a shrink operation;

read data from a second set of storage locations, wherein

the second set of storage locations is a second subset of the plurality of storage locations, and

the first set of storage locations and second set of storage locations are mutually exclusive; and

copy the data to a second storage object.

10. The computer readable storage medium of claim 9, wherein

the first storage object and second storage object comprise dynamic virtual disks.

11. The computer readable storage medium of claim 9, wherein

the first set of storage locations identifies portions of a first file, and

the first file is created by a virtual machine in response to the request.

12. The computer readable storage medium of claim 11, wherein the program instructions are further executable to:

detect completion of the shrink operation; and

delete the file in response to the detecting.

13. The computer readable storage medium of claim 9, wherein

the first set of storage locations corresponds to unused portions of the first storage object.

14. The computer readable storage medium of claim 9, wherein the program instructions are further executable to:

receive a second list, wherein the first list corresponds to unused portions of a first partition of the first storage object and the second list corresponds to unused portions of a second partition of the first storage object; and

merge the second list with the first list.

15. The computer readable storage medium of claim 9, wherein the program instructions are further executable to:

detect an attribute of the file, wherein the attribute indicates that creating the file does not require any input/output (I/O) operations.

16. The computer readable storage medium of claim 9, wherein the program instructions are further executable to:

allocate an amount of storage space for the second storage object in response to receiving the request, wherein

the amount of storage space equals a first amount of storage space allocated to the first storage object.

17. A system comprising:

one or more processors; and

a memory coupled to the one or more processors, wherein the memory stores program instructions executable by the one or more processors to;

receive a request to perform a shrink operation on a first storage object, wherein the first storage object comprises a plurality of storage locations;

receive a first list that identifies a first set of storage locations, wherein

the first set of storage locations is a first subset of the plurality of storage locations, and

the list is received in response to the request to perform a shrink operation;

read data from a second set of storage locations, wherein

the second set of storage locations is a second subset of the plurality of storage locations, and

the first set of storage locations and second set of storage locations are mutually exclusive; and

copy the data to a second storage object.

18. The system of claim 17, wherein

the first set of storage locations identifies portions of a first file,

the first file is created by a virtual machine in response to the request, and

the program instructions are further executable to

detect completion of the shrink operation, and

delete the file in response to the detecting.

19. The system of claim 17, wherein

the first set of storage locations corresponds to unused portions of the first storage object.

20. The system of claim 17, wherein the program instructions are further executable to:

receive a second list, wherein the first list corresponds to unused portions of a first partition of the first storage object and the second list corresponds to unused portions of a second partition of the first storage object; and

merge the second list with the first list.