BACKUP OF DEDUPLICATED DATA

• US 20100205389A1
• Filed: 02/06/2009
• Published: 08/12/2010
• Est. Priority Date: 02/06/2009
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: KISHI, GREGORY TAD
• Granted Patent: US 8,108,638 B2
• Time in Patent Office: Days
• US Class Current: 711/162
• CPC Class Codes: G06F 11/1453 using de-duplication of the data

Abstract

Methods and systems back up deduplicated data to data storage media, the deduplicated data comprising a plurality of data blocks referenced for deduplication. In one embodiment, the existence of multiple references to each of the data blocks is determined; and at least two copies of at least each data block having multiple references thereto is stored, each to a separate data storage media. In another embodiment, the references to each of the data blocks is determined; the total of multiple references is compared to a percentage threshold; and multiple copies are stored for all the data blocks where the percentage threshold is exceeded.

Claims

1. A method for backing up deduplicated data from a deduplicated data source, said deduplicated data comprising a plurality of data blocks referenced for deduplication, comprising:

a step performed by a processing system comprising determining the existence of multiple references to each of said data blocks; and

a step performed by a processing system comprising storing at least two copies of at least each said data block having multiple references thereto, each copy of said data block stored to separate data storage media.

2. A method for backing up deduplicated data from a deduplication source, said deduplicated data comprising a plurality of data blocks referenced for deduplication, comprising:

a step performed by a processing system comprising determining the references to each of said data blocks;

a step performed by a processing system comprising comparing said references to a reference threshold;

a step performed by a processing system comprising storing a single copy of each said data block where said reference threshold is not exceeded; and

a step performed by a processing system comprising storing multiple copies of each said data block where said reference threshold is exceeded.

3. The method of claim 2, wherein said multiple copy storing step performed by a processing system comprises storing each copy of said multiple copies of a data block to each of separate data storage media.

4. The method of claim 3, wherein said reference threshold comprises a number of references to a data block.

5. The method of claim 4, wherein said deduplicated data is arranged in data volumes, at least one of said data volumes comprising a plurality of said data blocks, and wherein said determined references to a data block of said determination step excludes multiple references to a data block in the same said data volume.

6. The method of claim 4, wherein said deduplicated data is arranged in data volumes, at least one of said data volumes comprising a plurality of said data blocks, and wherein said determined references to a data block of said determination step includes multiple references to a data block in the same said data volume.

7. The method of claim 4, wherein said reference threshold number is one reference to a data block.

8. The method of claim 3, wherein said reference threshold comprises a risk based threshold greater than one.

9. A method for backing up deduplicated data from a deduplication source, said deduplicated data comprising a plurality of data blocks referenced for deduplication, comprising:

a step performed by a processing system comprising determining the references to each of said data blocks in a context;

a step performed by a processing system comprising comparing the total of multiple said references in said context to a percentage threshold; and

a step performed by a processing system comprising storing all of said data blocks of said context, where said percentage threshold is exceeded.

10. The method of claim 9, wherein said deduplicated data is arranged in data volumes, at least one of said data volumes comprising a plurality of said data blocks;

wherein said percentage threshold comprises a percentage of data of a volume having multiple references to data blocks; and

wherein said storing step performed by a processing system comprises storing all said data blocks of said volume.

11. The method of claim 10, wherein said percentage threshold comprises a percentage of the number of said data blocks of said volume.

12. The method of claim 9, wherein said deduplicated data comprises a defined data stream comprising a plurality of data volumes;

wherein said percentage threshold comprises a percentage of data of said data stream having multiple references to data blocks; and

wherein said storing step performed by a processing system comprises storing all of said data of said data stream.

13. A method for backing up deduplicated data from a deduplication source, said deduplicated data comprising a plurality of data blocks referenced for deduplication, comprising:

a step performed by a processing system comprising determining the quantity of data of references to each of said data blocks in a context;

a step performed by a processing system comprising comparing the quantity of the data of said context to a percentage threshold; and

a step performed by a processing system comprising storing all of said data blocks of said context, where said percentage threshold is exceeded.

14. The method of claim 13, wherein said deduplicated data is arranged in data volumes;

wherein said percentage threshold comprises a percentage of quantity of data of a volume; and

wherein said storing step performed by a processing system comprises storing all said data blocks of said volume.

15. The method of claim 13, wherein said deduplicated data comprises a defined data stream comprising a plurality of data volumes;

wherein said percentage threshold comprises a percentage of the quantity of deduplicated data of said data stream; and

wherein said storing step performed by a processing system comprises storing all of said data of said data stream.

16. A method for backing up deduplicated data from a deduplication source, said deduplicated data comprising a plurality of data blocks referenced for deduplication, comprising:

a step performed by a processing system comprising determining the references to each of said data blocks;

a step performed by a processing system comprising comparing said references to a first threshold;

a step performed by a processing system comprising comparing said references to a second threshold;

a step performed by a processing system comprising storing a second copy of at least each said data block where said first threshold is exceeded; and

a step performed by a processing system comprising storing a copy in addition to said second copy of at least each said data block where said second threshold is exceeded.

17. The method of claim 16, wherein said multiple copy storing step performed by a processing system comprises storing each copy of said second copy of a data block and each copy of said additional copy of a data block to each of separate data storage media.

18. A system comprising:

at least one data storage drive configured to store data to at least one data storage medium; and

a processor system configured to back up deduplicated data to a plurality of separate data storage media via said at least one data storage drive, said deduplicated data comprising a plurality of data blocks referenced for deduplication, said processor system configured to;

determine for each of said data blocks whether multiple said references exist with respect to said data block; and

store at least two copies of at least each said data block having multiple references thereto, each copy of said data block stored to separate data storage media.

19. A system comprising:

at least one data storage drive configured to store data to at least one data storage medium; and

a processor system configured to back up deduplicated data to a plurality of separate data storage media via said at least one data storage drive, said deduplicated data comprising a plurality of data blocks referenced for deduplication, said processor system configured to;

determine the references to each of said data blocks;

compare said references to a reference threshold;

store a single copy to a data storage media of each said data block where said reference threshold is not exceeded; and

store a separate copy to each of separate data storage media of each said data block where said reference threshold is exceeded.

20. The system of claim 19, wherein said reference threshold comprises a number of references to a data block;

wherein said deduplicated data is arranged in data volumes, at least one of said data volumes comprising a plurality of said data blocks, and wherein said processor system is configured to determine references to a data block excluding multiple references to a data block in the same said data volume.

21. The system of claim 19, wherein said reference threshold comprises a number of references to a data block;

wherein said deduplicated data is arranged in data volumes, at least one of said data volumes comprising a plurality of said data blocks, and wherein said processor system is configured to determine references to a data block including multiple references to a data block in the same said data volume.

22. A system comprising:

at least one data storage drive configured to store data to at least one data storage medium; and

a processor system configured to back up deduplicated data to a plurality of separate data storage media via said at least one data storage drive, said deduplicated data comprising a plurality of data blocks referenced for deduplication, said processor system configured to;

determine the references to each of said data blocks in a context;

compare the total of multiple said references in said context to a percentage threshold; and

store all of said data blocks of said context, where said percentage threshold is exceeded.

23. The system of claim 22, wherein said deduplicated data is arranged in data volumes, at least one of said data volumes comprising a plurality of said data blocks;

wherein said percentage threshold comprises a percentage of data of a volume having multiple references to data blocks; and

wherein said processor system is configured to store all said data blocks of said volume where said percentage threshold is exceeded.

24. The system of claim 23, wherein said percentage threshold comprises a percentage of the number of said data blocks of said volume.

25. The system of claim 22, wherein said deduplicated data comprises a defined data stream comprising a plurality of data volumes;

wherein said percentage threshold comprises a percentage of data of said data stream having multiple references to data blocks; and

wherein said processor system is configured to store all said data of said data stream where said percentage threshold is exceeded.

26. A system comprising:

at least one data storage drive configured to store data to at least one data storage medium; and

a processor system configured to back up deduplicated data to a plurality of separate data storage media via said at least one data storage drive, said deduplicated data comprising a plurality of data blocks referenced for deduplication, said processor system configured to;

determine the quantity of data of references to each of said data blocks in a context;

compare the quantity of data of said context to a percentage threshold; and

store all of said data blocks of said context, where said percentage threshold is exceeded.

27. The system of claim 26, wherein said deduplicated data is arranged in data volumes;

wherein said percentage threshold comprises a percentage of quantity of data of a volume; and

wherein said processor system is configured to store all said data blocks of said volume where said percentage threshold is exceeded.

28. The system of claim 26, wherein said deduplicated data comprises a defined data stream comprising a plurality of data volumes;

wherein said percentage threshold comprises a percentage of the quantity of deduplicated data of said data stream; and

wherein said processor system is configured to store all said data of said data stream where said percentage threshold is exceeded.

29. A system comprising:

at least one data storage drive configured to store data to at least one data storage medium; and

a processor system configured to back up deduplicated data to a plurality of separate data storage media via said at least one data storage drive, said deduplicated data comprising a plurality of data blocks referenced for deduplication, said processor system configured to;

determine the references to each of said data blocks;

compare said references to a first threshold;

compare said references to a second threshold;

store a second copy of at least each said data block to said separate data storage media where said first threshold is exceeded; and

store a copy in addition to said second copy to said separate data storage media of at least each said data block where said second threshold is exceeded.