SYSTEM AND METHOD FOR OPTIMIZING MIRROR CREATION

• US 20120109897A1
• Filed: 10/27/2010
• Published: 05/03/2012
• Est. Priority Date: 10/27/2010
• Status: Active Grant

• Current Assignee: Veritas Technologies, LLC (Whitehouse Group Ltd.)
• Original Assignee: Symantec Corporation (NortonLifeLock Inc.)
• Inventors: Janakiraman, Viswesvaran, Lin, Chris Chih-Chen, Tiruvayapadi, Mohankumar R.
• Granted Patent: US 9,934,108 B2
• Time in Patent Office: Days
• US Class Current: 707/660
• CPC Class Codes: G06F 11/1466 to make the backup process non-disruptive
• CPC Class Codes: G06F 2201/815 Virtual middleware or OS functionality using virtual machines to implement generic software techniques for error detection or fault masking G06F11/1484

Abstract

Embodiments of the present invention are directed to a method and system for optimizing mirror creation. The method includes receiving, within an electronic system, a request for creating a mirror of a portion of a volume and accessing a data structure comprising information about a plurality of regions of the volume. The method further includes determining a plurality of regions comprising non-zeros of the volume based on the data structure and copying only the plurality of regions comprising non-zeros to create the mirror.

Claims

1. A method for optimizing mirror creation comprising:

receiving, within an electronic system, a request for creating a mirror of a volume associated with a virtual machine;

accessing a data structure comprising information about a plurality of regions of said volume;

determining a plurality of regions comprising non-zeros of said volume based on said data structure; and

copying only said plurality of regions comprising non-zeros to a destination volume to create said mirror.

2. The method of claim 1 further comprising:

updating said data structure based on each write request received.

3. The method of claim 2 wherein said updating further comprises:

receiving a write request wherein a portion of said write request corresponds to a region of said volume;

determining whether performance of said write request comprises writing a non-zero value to said region;

performing said write request for said region provided said write request comprises writing said non-zero value to said region; and

updating said data structure based on writing said non-zero value to said region.

4. The method of claim 3 further comprising:

determining whether performance of said write request comprises writing zeros to said region;

determining whether a value of said data structure corresponding to said region indicates said region comprises only zeros; and

emulating said write request when said value of said data structure corresponding to said region indicates said region comprises zeros and said write request involves writing zeros to said region.

5. The method of claim 4 further comprising:

performing said write request when said indicator of said data structure corresponding to said region indicates said region comprises zeros and said write request comprises writing said non-zero value to said region.

6. The method of claim 2 further comprising:

receiving a read request for a region; and

determining whether said region comprises zeros based on said data structure.

7. The method of claim 6 further comprising:

emulating said read request when said region comprises zeros based on said data structure.

8. The method of claim 1 further comprising:

determining deallocated space corresponding to a deleted file; and

writing zeros to a region corresponding to said deleted file.

9. The method of claim 1 further comprising:

;

detecting a format command; and

updating said data structure based on said format command.

10. A computer readable storage medium having stored thereon, computer executable instructions that, if executed by a computer system cause the computer system to perform a method for optimizing mirror creation comprising:

receiving, within an electronic system, a request for creating a mirror of a portion of a volume;

accessing a data structure comprising information about a plurality of regions of said volume;

determining a plurality of regions comprising non-zeros of said volume based on said data structure; and

copying said plurality of regions comprising non-zeros to a destination volume.

11. The computer readable storage medium of claim 10, wherein said method further comprises:

maintaining said data structure based on each read request and each write request received.

12. The computer readable storage medium of claim 11, wherein said maintaining further comprises:

receiving a write request wherein a portion of said write request corresponds to a region of said volume;

determining whether performance of said write request comprises writing a non-zero value to said region;

performing said write request for said region when said write request comprises writing said non-zero value to said region; and

updating said data structure based on writing said non-zero value to said region.

13. The computer readable storage medium of claim 12, wherein said maintaining further comprises:

determining whether performance of said write request comprises writing zeros to said region; and

determining whether a value of said data structure corresponding to said region indicates said region comprises zeros; and

emulating said write request when said value of said data structure corresponding to said region indicates said region comprises zeros and said write request involves writing zeros to said region.

14. The computer readable storage medium of claim 13, wherein said maintaining further comprise:

performing said write request when said indicator of said data structure corresponding to said region indicates said region comprises zeros and said write request comprises writing said non-zero value to said region.

15. The computer readable storage medium of claim 11, wherein said maintaining further comprises:

receiving a read request for said region; and

determining whether said region comprises zeros based on said data structure.

16. The computer readable storage medium of claim 15, said maintaining further comprises:

emulating said read request when said region comprises zeros based on said data structure.

17. The computer readable storage medium of claim 15, said method further comprises:

determining deallocated space corresponding to a deleted file; and

writing zeros to a region corresponding to said deleted file.

19. The storage access system of claim 17, wherein said method further comprises:

determining deallocated space corresponding to a deleted file; and

writing zeros to a region corresponding to said deleted file.

20. The storage access system of claim 17 wherein said method further comprises:

detecting a format command; and

updating said data structure based on said format command.

18. A storage access system, comprising:

a computer system comprising one or more processors coupled to a computer readable storage media and configurable to execute computer readable code stored on the computer readable storage media which causes the computer system to implement a method comprising;

receiving, within an electronic system, a request for creating a mirror of a portion of a volume;

accessing a data structure comprising information about a plurality of regions of said volume;

determining a plurality of regions comprising non-zeros of said volume based on said data structure; and

copying said plurality of regions comprising non-zeros to a destination volume.