VIRTUALIZATION OF METADATA FOR FILE OPTIMIZATION

• US 20090216774A1
• Filed: 02/27/2008
• Published: 08/27/2009
• Est. Priority Date: 02/27/2008
• Status: Active Grant

• Current Assignee: Quest Software, Inc.
• Original Assignee: Ocarina Networks, Inc. (Dell Technologies Inc.)
• Inventors: Brueggemann, Eric, Rao, Goutham, George, Carter, Bashyam, Murali, Taylor, Mark
• Granted Patent: US 8,224,831 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1453 using de-duplication of the data
• CPC Class Codes: G06F 16/1744 using compression, e.g. sparse files
• CPC Class Codes: G06F 16/1748 De-duplication implemented within the file system, e.g. based on file segments de-duplication techniques in storage systems for the management of data blocks G06F3/0641
• CPC Class Codes: G06F 16/2322 using timestamps

Abstract

Mechanisms are provided for optimizing files while allowing application servers access to metadata associated with preoptimized versions of the files. During file optimization involving compression and/or compaction, file metadata changes. In order to allow file optimization in a manner transparent to application servers, the metadata associated with preoptimized versions of the files is maintained in a metadata database as well as in an optimized version of the files themselves.

Claims

1. A method, comprising:

receiving a request for metadata associated with a first file, the request received from an application running on an application server connected to a file server over a network;

accessing a metadata database for the metadata associated with the first file, the metadata corresponding to a preoptimized version of the first file;

wherein an optimized version of the first file is accessed when the metadata associated with the first file is not available in the metadata database, the optimized version of the first file including compressed data from the first file and metadata corresponding to the preoptimized version of the first file.

2. The method of claim 1, wherein the metadata database includes file identifiers, access times, and metadata.

3. The method of claim 2, wherein file identifiers include user identifiers, group identifiers, and inode numbers.

4. The method of claim 2, wherein access times include times corresponding files were last accessed.

5. The method of claim 2, wherein metadata includes file names and file sizes associated with preoptimized versions of corresponding files.

6. The method of claim 1, wherein the database resides at the application server.

7. The method of claim 1, wherein the contents of the metadata database are prefetched during a directory listing request.

8. The method of claim 7, wherein prefetching allows accelerated retrieval of metadata during subsequent requests.

9. The method of claim 1, wherein the database resides at the file server.

10. The method of claim 1, wherein the database resides at a network device between the application server and the file server.

11. The method of claim 1, wherein the optimized version of the first file comprises compressed and compacted data.

18. The method of claim 1, wherein the contents of the metadata database are prefetched during a directory listing request.

19. The method of claim 18, wherein prefetching allows accelerated retrieval of metadata during subsequent requests.

12. A system, comprising:

an interface operable to receive a request for metadata associated with a first file, the request received from an application running on an application server connected to the system over a network;

a processor operable to access a metadata database for the metadata associated with the first file, the metadata corresponding to a preoptimized version of the first file;

wherein an optimized version of the first file is accessed when the metadata associated with the first file is not available in the metadata database, the optimized version of the first file including compressed data from the first file and metadata corresponding to the preoptimized version of the first file.

13. The system of claim 12, wherein the metadata database includes file identifiers, access times, and metadata.

14. The system of claim 13, wherein file identifiers include user identifiers, group identifiers, and inode numbers.

15. The system of claim 13, wherein access times include times corresponding files were last accessed.

16. The system of claim 13, wherein metadata includes file names and file sizes associated with preoptimized versions of corresponding files.

17. The system of claim 12, wherein the database resides at the application server.

20. The system of claim 12, wherein the database resides at the file server.

21. The system of claim 12, wherein the database resides at a network device between the application server and the file server.

22. The system of claim 12, wherein the optimized version of the first file comprises compressed and compacted data.

23. An apparatus, comprising:

means for receiving a request for metadata associated with a first file, the request received from an application running on an application server connected to a file server over a network;

means for accessing a metadata database for the metadata associated with the first file, the metadata corresponding to a preoptimized version of the first file;

means for wherein an optimized version of the first file is accessed when the metadata associated with the first file is not available in the metadata database, the optimized version of the first file including compressed data from the first file and metadata corresponding to the preoptimized version of the first file.

24. The apparatus of claim 23, wherein the metadata database includes file identifiers, access times, and metadata.

25. The apparatus of claim 24, wherein file identifiers include user identifiers, group identifiers, and inode numbers.

26. The apparatus of claim 24, wherein access times include times corresponding files were last accessed.

27. A computer readable medium having computer code embodied therein, the computer readable medium comprising:

computer code for receiving a request for metadata associated with a first file, the request received from an application running on an application server connected to a file server over a network;

computer code for accessing a metadata database for the metadata associated with the first file, the metadata corresponding to a preoptimized version of the first file;

wherein an optimized version of the first file is accessed when the metadata associated with the first file is not available in the metadata database, the optimized version of the first file including compressed data from the first file and metadata corresponding to the preoptimized version of the first file.