OPTIMIZED COPY OF VIRTUAL MACHINE STORAGE FILES

• US 20110035358A1
• Filed: 08/07/2009
• Published: 02/10/2011
• Est. Priority Date: 08/07/2009
• Status: Active Grant

• Current Assignee: Quest Software, Inc.
• Original Assignee: Quest Software, Inc.
• Inventors: Naik, Dilip
• Granted Patent: US 9,778,946 B2
• Time in Patent Office: Days
• US Class Current: 707/640
• CPC Class Codes: G06F 16/10 File systems; File servers
• CPC Class Codes: G06F 16/113 Details of archiving lifecycle management in storage systems G06F3/0649; backup systems G06F11/1446
• CPC Class Codes: G06F 16/128 Details of file system snapshots on the file-level, e.g. snapshot creation, administration, deletion use of snapshots for error detection or correction G06F11/14, G06F11/16
• CPC Class Codes: G06F 16/27 Replication, distribution or synchronisation of data between databases or within a distributed database system; Distributed database system architectures therefor
• CPC Class Codes: G06F 2009/45562 Creating, deleting, cloning virtual machine instances
• CPC Class Codes: G06F 9/45558 Hypervisor-specific management and integration aspects

Abstract

A facility is described for optimizing the copying of virtual machine storage files. In various embodiments, the facility refrains from copying portions of the virtual machine storage file that do not contain any meaningful data for the purposes of the guest file system within the virtual machine storage file. In some embodiments, the facility refrains from copying portions of the file that are in use by the guest file system, but are of no practical value.

Claims

1. A method performed by a computer system for performing an optimized copy of virtual machine storage files, comprising:

identifying a file system;

obtaining a file system cluster size and a number of clusters for the identified file system;

identifying a location within a virtual machine storage file of a first cluster; and

copying the virtual machine storage file from a beginning of the virtual machine storage file to the identified location to a destination file.

2. The method of claim 1 further comprising:

receiving a cluster bitmap;

determining whether additional clusters remain to be processed; and

if additional clusters remain to be processed, processing the cluster bitmap.

3. The method of claim 2 wherein the processing includes determining if a cluster bitmap indicates that data is in use.

4. The method of claim 3 wherein if the data is in use, copying the corresponding data to the destination file.

5. The method of claim 3 wherein if the data is not in use, advancing a file pointer by the cluster size.

6. The method of claim 2 wherein if no additional clusters remain to be processed, copying the virtual machine storage file from a previous cluster location to an end of the virtual machine storage file.

7. The method of claim 6 further comprising setting file metadata.

8. The method of claim 1 further comprising only copying occupied data blocks.

9. The method of claim 1 further comprising avoiding copying blocks occupied by files deemed to be uninteresting.

10. The method of claim 9 wherein uninteresting files are files within a guest filesystem within the virtual machine storage file.

11. The method of claim 1 wherein the virtual machine storage file being copied comprises an operating system image with its appropriate file system.

12. The method of claim 1 wherein the virtual machine storage file being copied comprises just a guest file system, but no operating system image.

13. The method of claim 1 wherein the virtual machine storage file being copied comprises of a single volume embedded within it

14. The method of claim 1 wherein the virtual machine storage file being copied comprises multiple volumes embedded within it.

15. The method of claim 1 wherein the optimization consists of avoiding copying the portions of the virtual machine storage file that do not contain any meaningful data for the purposes of the guest file system.

16. The method of claim 1 wherein the optimization consists of avoiding copying the portions of the virtual machine storage file that contain data as determined from the point of view of the guest file system within the file being copied, but said data would be irrelevant.

17. The method of claim 1 wherein the facility system executes on a computer system with any version of the Microsoft Windows operating system.

18. The method of claim 1 wherein the facility system executes on a computer system with an operating system for APPLE MACINTOSH computers.

19. The method of claim 1 wherein the facility system executes on a computer system with any of the Unix and Linux operating systems

20. The method of claim 1 wherein the facility is copying a virtual machine storage file containing the Windows NTFS file system

21. The method of claim 1 wherein the facility is copying a virtual machine storage file containing the FAT, FAT32 or exFAT file system

22. The method of claim 1 wherein the facility is copying a virtual machine storage file containing a file system used with the UNIX operating system such as EXT3, EXT4, RaiserFS, XFS, JFS, or ZFS

23. The method of claim 1 wherein the facility is copying a virtual machine storage file containing the Apple file system

24. The method of claim 1 wherein the facility is copying a virtual machine storage file consisting of the Microsoft specified VHD file format.

25. The method of claim 1 wherein the facility is copying a virtual machine storage file consisting of the VMware specified VMDK file format.

26. The method of claim 1 wherein the facility is copying a virtual machine storage file to multiple destination files