Dynamic rewrite of files within deduplication system

• US 8,438,139 B2
• Filed: 12/01/2010
• Issued: 05/07/2013
• Est. Priority Date: 12/01/2010
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Aronovich, Lior, Krikler, Samuel, Levy, Asaf, Schreiber, Amit
• Primary Examiner(s): Jalil, Neveen Abel
• Assistant Examiner(s): BUCKINGHAM, KELLYE DEE
• Application Number:
  US12/958,200
• Publication Number:
  US 20120143832A1
• Time in Patent Office: 888 Days
• Field of Search: None
• 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

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

a plurality of user files including original deduplication (DFS) files;

a sequential deduplication file system in communication with the plurality of user files;

a dynamic non-deduplicated file system in communication with the plurality of user files including a plurality of dynamic metadata files having entries pointing to corresponding sections of the original DFS files; and

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

creating a new deduplication file system (DFS) file to be stored as part of the plurality of user files,

directly writing rewritten sections of one of the original DFS files resulting from rewrite operations into the new DFS file,

quoting unmodified sections of the one of the original DFS files unaffected by rewrite operations into the new DFS file, and

deleting the one of the original DFS files.

2. The system of claim 1, wherein the at least one processor device is further adapted for quoting the unmodified sections of the one of the original DFS files into additional new DFS files.

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

4. The system of claim 1, 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.

9. The system of claim 1, further comprising a dynamic file system layer configured to use the sequential deduplication file system and the dynamic non-deduplicated file system to implement the user files.

10. The system of claim 2, wherein the dynamic file system layer is above the sequential deduplication file system and the dynamic non-deduplicated file system.

11. The system of claim 4, further comprising replacing entries in a dynamic metadata file associated with the deleted one of the original DFS files with new entries pointing to the new DFS.

5. 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 creating a new deduplication file system (DFS) file to be stored as part of a plurality of user files, the plurality of user files including original deduplication file system (DFS) files and being accessible by a sequential deduplication file system and a dynamic non-deduplicated file system, the dynamic non-deduplicated file system including a plurality of dynamic metadata files having entries pointing to corresponding sections of the original DFS files;

a second executable portion for directly writing rewritten sections of one of the original DFS files resulting from rewrite operations into the new DFS file;

a third executable portion for quoting unmodified sections of the one of the original DFS files unaffected by rewrite operations into the new DFS file; and

a fourth executable portion for deleting the one of the original DFS files.

6. The computer program product of claim 5, wherein quoting the unmodified sections of the one of the original DFS files may be performed into additional new DFS files.

7. The computer program product of claim 5, wherein the sequential deduplication file system is static.

8. The computer program product of claim 5, 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.

12. The computer program product of claim 5, further comprising a fifth executable portion for implementing the user files using a dynamic file system layer configured to use the sequential deduplication file system and the dynamic non-deduplicated file system to implement the user files.

13. The computer program product of claim 12, wherein the dynamic file system layer is above the sequential deduplication file system and the dynamic non-deduplicated file system.

14. The computer program product of claim 8, further comprising a fifth executable portion for replacing entries in a dynamic metadata file associated with the deleted one of the original DFS files with new entries pointing to the new DFS.