DYNAMIC REWRITE OF FILES WITHIN DEDUPLICATION SYSTEM

• US 20120143832A1
• Filed: 12/01/2010
• Published: 06/07/2012
• Est. Priority Date: 12/01/2010
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: ARONOVICH, Lior, LEVY, Asaf, SCHREIBER, Amit, KRIKLER, Samuel
• Granted Patent: US 8,438,139 B2
• Time in Patent Office: Days
• US Class Current: 707/692
• 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

Abstract

Various embodiments for rewriting data in a deduplication storage environment by a processor device are provided. A dynamic layer above a sequential deduplication file system (denoted as DFS) implements the rewrite functionality. A user file is composed of one or more DFS files. As incoming data is written into a user file, the data is written by the dynamic layer sequentially into DFS files, created one by one. For each user file this dynamic layer creates and maintains a dynamic metadata file, in a regular, non deduplicated file system. This metadata file contains entries pointing to sections of DFS files.

Claims

1. A method for rewriting data in a deduplication storage environment by a processor device, comprising:

storing rewritten data in new deduplication file system (DFS) files;

quoting unmodified data from original DFS files affected by rewrite operations into new DFS files; and

deleting the original DFS files.

2. The method of claim 1, wherein quoting the unmodified data from the original DFS files may be performed into one of the new DFS files containing the rewritten data and additional new DFS files.

3. The method of claim 1, wherein the deduplication file system is sequential and static.

4. The method of claim 1, wherein user files are represented by dynamic metadata files residing in a regular, non-deduplicated file system.

5. The method of claim 4, wherein each of the user files is composed of a plurality of DFS files.

6. The method of claim 5, wherein the dynamic metadata files include a plurality of entries, each entry representing a reference between a section in one of the user files and a section in one of the DFS files.

7. The method of claim 6, wherein the entries of one of the dynamic metadata files may be modified to reflect a new layout of one of the user files over the DFS files.

8. A system for rewriting data in a deduplication storage environment, comprising:

at least one processor device, operable in the deduplication storage environment, wherein the at least one processor device is adapted for;

storing rewritten data in new deduplication file system (DFS) files,

quoting unmodified data from original DFS files affected by rewrite operations into new DFS files, and

deleting the original DFS files.

9. The system of claim 8, wherein the at least one processor device is further adapted for performing quoting the unmodified data from the original DFS files into one of the new DFS files containing the rewritten data and additional new DFS files.

10. The system of claim 8, wherein the deduplication file system is sequential and static.

11. The system of claim 8, wherein user files are represented by dynamic metadata files residing in a regular, non-deduplicated file system.

12. The system of claim 11, wherein each of the user files is composed of a plurality of DFS files.

13. The system of claim 12, wherein the dynamic metadata files include a plurality of entries, each entry representing a reference between a section in one of the user files and a section in one of the DFS files.

14. The system of claim 13, wherein the entries of one of the dynamic metadata files may be modified to reflect a new layout of one of the user files over the DFS files.

15. A computer program product for rewriting data in a deduplication storage environment by at least one processor device, the computer program product comprising a computer-readable storage medium having computer-readable program code portions stored therein, the computer-readable program code portions comprising:

a first executable portion for storing rewritten data in new deduplication file system (DFS) files;

a second executable portion for quoting unmodified data from original DFS files affected by rewrite operations into new DFS files; and

a third executable portion for deleting the original DFS files.

16. The computer program product of claim 15, wherein quoting the unmodified data from the original DFS files may be performed into one of the new DFS files containing the rewritten data and additional new DFS files.

17. The computer program product of claim 15, wherein the deduplication file system is sequential and static.

18. The computer program product of claim 15, wherein user files are represented by dynamic metadata files residing in a regular, non-deduplicated file system.

19. The computer program product of claim 18, wherein each of the user files is composed of a plurality of DFS files.

20. The computer program product of claim 19, wherein the dynamic metadata files include a plurality of entries, each entry representing a reference between a section in one of the user files and a section in one of the DFS files.

21. The computer program product of claim 20, wherein the entries of one of the dynamic metadata files may be modified to reflect a new layout of one of the user files over the DFS files.