PRODUCING ALTERNATIVE SEGMENTATIONS OF DATA INTO BLOCKS IN A DATA DEDUPLICATION SYSTEM

• US 20150019508A1
• Filed: 07/15/2013
• Published: 01/15/2015
• Est. Priority Date: 07/15/2013
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: ARONOVICH, Lior
• Granted Patent: US 9,922,042 B2
• Time in Patent Office: Days
• US Class Current: 707/692
• CPC Class Codes: G06F 16/1752 based on file chunks

Abstract

For producing secondary segmentations of data into blocks and corresponding digests for input data in a data deduplication system using a processor device in a computing environment, digests are calculated for an input data chunk using a primary segmentation into blocks. Secondary segmentations are produced for each of the data mismatches based on reference data, and used to calculate further data matches. The primary segmentation and the corresponding primary digests are stored for the input data chunk.

Claims

9. A system for producing a plurality of segmentations of input data into blocks in a data deduplication system of a computing environment, the system comprising:

the data deduplication system;

a repository operating in the data deduplication system;

a memory in the data deduplication system;

a search structure in association with the memory in the data deduplication system; and

at least one processor device operable in the computing storage environment for controlling the data deduplication system, wherein the at least one processor device;

calculates digests for an input data chunk using a primary segmentation,

obtains and applies secondary segmentations for each one of a plurality of data mismatches based on reference data, and

stores the primary segmentation and corresponding primary digests for the input data chunk.

10. The system of claim 9, wherein the at least one processor device produces data matches and the data mismatches by searching input digests in a search structure of reference digests.

11. The system of claim 9, wherein the at least one processor device obtains the segmentations for each one of the data mismatches by considering input digests included in data matches preceding and following each one of the data mismatches.

12. The system of claim 11, wherein the at least one processor device matches the considered input digests with reference digests to produce alternative digest matches.

13. The system of claim 12, wherein the at least one processor device defines the alternative digests matches to serve as starting positions for the secondary segmentations which are projected onto the input data.

14. The system of claim 13, wherein the at least one processor device performs one of:

calculating new digest values for the input data based on the secondary segmentations, and

searching new digest values in a search structure of reference digest values to produce new digests matches.

15. The system of claim 14, wherein the at least one processor device generates new data matches corresponding to the produced new digests matches.

16. The system of claim 15, wherein the at least one processor device avoids storing the secondary segmentations and corresponding secondary digests for the input data chunk.

17. A computer program product for producing a plurality of segmentations of input data into blocks in a data deduplication system using a processor device in a computing environment, 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 that calculates digests for an input data chunk using a primary segmentation;

a second executable portion that obtains and applies secondary segmentations for each one of a plurality of data mismatches based on reference data; and

a third executable portion that stores the primary segmentation and corresponding primary digests for the input data chunk.

1. A method for producing a plurality of segmentations of input data into blocks in a data deduplication system using a processor device in a computing environment, comprising:

calculating digests for an input data chunk using a primary segmentation;

obtaining and applying secondary segmentations for each one of a plurality of data mismatches based on reference data; and

storing the primary segmentation and corresponding primary digests for the input data chunk.

2. The method of claim 1, further including producing data matches and the data mismatches by searching input digests in a search structure of reference digests.

3. The method of claim 1, further including obtaining the segmentations for each one of the data mismatches by considering input digests included in data matches preceding and following each one of the data mismatches.

4. The method of claim 3, further including matching the considered input digests with reference digests to produce alternative digest matches.

5. The method of claim 4, further including defining the alternative digests matches to serve as starting positions for the secondary segmentations which are projected onto the input data.

6. The method of claim 5, further including one of:

calculating new digest values for the input data based on the secondary segmentations; and

searching new digest values in a search structure of reference digest values to produce new digests matches.

7. The method of claim 6, further including generating new data matches corresponding to the produced new digests matches

8. The method of claim 1, further including avoiding storing the secondary segmentations and corresponding secondary digests for the input data chunk.

18. The computer program product of claim 17, further including a fourth executable portion that produces data matches and the data mismatches by searching input digests in a search structure of reference digests.

19. The computer program product of claim 18, further including a fifth executable portion that matches the considered input digests with reference digests to produce alternative digest matches.

20. The computer program product of claim 19, further including a sixth executable portion that defines the alternative digests matches to serve as starting positions for the secondary segmentations which are projected onto the input data.

21. The computer program product of claim 20, further including a seventh executable portion that performs one of:

calculating new digest values for the input data based on the secondary segmentations, and

searching new digest values in a search structure of reference digest values to produce new digests matches.

22. The computer program product of claim 21, further including an eighth executable portion that generates new data matches corresponding to the produced new digests matches.

18-1. The computer program product of claim 17, further including a fourth executable portion that obtains the segmentations for each one of the data mismatches by considering input digests included in data matches preceding and following each one of the data mismatches.

24. The computer program product of claim 23, further including a ninth executable portion that avoids storing the secondary segmentations and corresponding secondary digests for the input data chunk.