TRANSFORMATION OF LOGICAL DATA OBJECTS FOR STORAGE

• US 20110302219A1
• Filed: 08/12/2011
• Published: 12/08/2011
• Est. Priority Date: 01/13/2010
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: AMIT, Jonathan, KOIFMAN, Chaim, RAIKHMAN, Rostislav
• Granted Patent: US 8,688,753 B2
• Time in Patent Office: Days
• US Class Current: 707/802
• CPC Class Codes: G06F 3/0611 in relation to response time
• CPC Class Codes: G06F 3/0667 at data level, e.g. file, record or object virtualisation
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]

Abstract

Various embodiments for operating a transformation system, capable of transforming a logical data object (LO) to a transformed logical data object (TLO), are provided. In one such embodiment, an open LO request to a certain LO and addressed by the at least one client to the at least one storage device, is intercepted. An identifier (ID) in a header of a TLO corresponding to the requested LO and stored in the at least one storage device, is obtained. The obtained ID is used to characterize the TLO and the LO. A determination is made whether the transformation system handles at least one open LO characterized by an ID with a same value as the obtained ID. The requested LO is opened if at least one open LO is not found. An instance corresponding to the intercepted open LO request is generated. The instance is associated to the obtained ID.

Claims

1. A method for operating an identification map associated with a transformation system operatively coupled to a plurality of clients and a storage device and configured to transform a plurality of logical data objects (LOs) including a plurality of identifiers (IDs) to a plurality of transformed logical data objects (TLOs) for storage in the storage device, the method comprising:

mapping, by a first data repository, new IDs and currently open LOs; and

mapping, by a second data repository, old IDs and the new IDs associated with the currently open LOs.

2. The method of claim 1, wherein mapping the new IDs and the currently open LOs comprises updating one of ID entries, data on open instances, and associations between the new IDs and the currently open LOs.

3. The method of claim 1, wherein mapping the old IDs and the new IDs comprises updating old ID entries and last ID entries corresponding to the currently open LOs.

4. The method of claim 3, wherein mapping the new IDs and the currently open LOs comprises updating one of ID entries, data on open instances, and associations between the new IDs and the currently open LOs.

5. The method of claim 1, further comprising:

receiving, by the transformation system, an input/output (I/O) request related to a currently open LO;

performing the I/O request; and

updating an ID in a header in the currently open LO, wherein mapping the new IDs and currently open LOs comprises;

adding a new entry ID related to the currently open LO in the first data repository,

removing an old entry ID related to the currently open LO from the first data repository, and

associating an instance related to the I/O request with the new entry ID.

6. The method of claim 5, wherein mapping the old IDs and the new IDs comprises:

maintaining the old entry ID in the second data repository;

adding the new entry ID to the second data repository; and

associating the new entry ID and the old entry ID in the second data repository.

7. The method of claim 6, wherein mapping the old IDs and the new IDs further comprises recording, by the second data repository, a time stamp each time a ID related to each open LO is updated.

8. The method of claim 7, wherein the I/O request comprises the ID of the currently open LO and a first timestamp of the request, the method further comprising:

determining if the ID is found in the second data repository;

determining if the first timestamp is lower than a second timestamp of the ID in the second data repository;

issuing a read header request with an updated timestamp;

comparing the first timestamp and the updated ID;

repeating the issuing and comparing process until the updated timestamp is more recent then the second timestamp; and

processing the I/O request when the updated timestamp is more recent then the second timestamp.

9. A storage system, comprising:

a storage device comprising a first data repository and a second data repository; and

a transformation system comprising a processor operatively coupled to at least one client and the storage device, the transformation system configured to transform a logical data object (LO) to a transformed logical data object (TLO) for storage in the storage device operable with at least one storage protocol, wherein the processor is configured to;

map, in the first data repository, new IDs and currently open LOs, and

map, in the second data repository, old IDs and the new IDs associated with the currently open LOs.

10. The system of claim 9, wherein, when mapping the new IDs and the currently open LOs, the processor is configured to update one of ID entries, data on open instances, and associations between the new IDs and the currently open LOs.

11. The system of claim 9, wherein, when mapping the old IDs and the new IDs, the processor is configured to update old ID entries and last ID entries corresponding to the currently open LOs.

12. The system of claim 11, wherein, when mapping the new IDs and the currently open LOs, the processor is configured to update one of ID entries, data on open instances, and associations between the new IDs and the currently open LOs.

13. The system of claim 9, wherein the processor is further configured to:

receive an input/output (I/O) request related to a currently open LO;

perform the I/O request; and

update an ID in a header in the currently open LO, wherein, when mapping the new IDs and currently open LOs, the processor is further configured to;

add a new entry ID related to the currently open LO in the first data repository,

remove an old entry ID related to the currently open LO from the first data repository, and

associate an instance related to the I/O request with the new entry ID.

14. The system of claim 13, wherein, when mapping the old IDs and the new IDs, the processor is further configured to:

maintain the old entry ID in the second data repository;

add the new entry ID to the second data repository; and

associate the new entry ID and the old entry ID in the second data repository.

15. The system of claim 14, wherein, when mapping the old IDs and the new IDs, the processor is further configured to record, in the second data repository, a time stamp each time a ID related to each open LO is updated.

16. The system of claim 15, wherein the I/O request comprises the ID of the currently open LO and a first timestamp of the request, the processor further configured to:

determine if the ID is found in the second data repository;

determine if the first timestamp is lower than a second timestamp of the ID in the second data repository;

issue a read header request with an updated timestamp;

compare the first timestamp and the updated ID;

repeat the issuing and comparing process until the updated timestamp is more recent then the second timestamp; and

process the I/O request when the updated timestamp is more recent then the second timestamp.

17. A computer program product comprising a computer useable medium including a computer readable program code embodied therein for operating an identification map associated with a transformation system operatively coupled to a plurality of clients and a storage device and configured to transform a plurality of logical data objects (LOs) including a plurality of identifiers (IDs) to a plurality of transformed logical data objects (TLOs) for storage in the storage device, the computer program product comprising:

computer code for mapping, by a first data repository, new IDs and currently open LOs; and

computer code for mapping, by a second data repository, old IDs and the new IDs associated with the currently open LOs.

18. The computer program product of claim 17, wherein the computer code for mapping the new IDs and the currently open LOs comprises computer code for updating one of ID entries, data on open instances, and associations between the new IDs and the currently open LOs.

19. The computer program product of claim 17, wherein the computer code for mapping the old IDs and the new IDs comprises computer code for updating old ID entries and last ID entries corresponding to the currently open LOs.

20. The computer program product of claim 19, wherein the computer code for mapping the new IDs and the currently open LOs comprises computer code for updating one of ID entries, data on open instances, and associations between the new IDs and the currently open LOs.

21. The computer program product of claim 17, further comprising:

computer code for receiving, by the transformation system, an input/output (I/O) request related to a currently open LO;

computer code for performing the I/O request; and

computer code for updating an ID in a header in the currently open LO, wherein the computer code for mapping the new IDs and currently open LOs comprises;

computer code for adding a new entry ID related to the currently open LO in the first data repository,

computer code for removing an old entry ID related to the currently open LO from the first data repository, and

computer code for associating an instance related to the I/O request with the new entry ID.

22. The computer program product of claim 21, wherein the computer code for mapping the old IDs and the new IDs comprises:

computer code for maintaining the old entry ID in the second data repository;

computer code for adding the new entry ID to the second data repository; and

computer code for associating the new entry ID and the old entry ID in the second data repository.

23. The computer program product of claim 22, wherein the computer code for mapping the old IDs and the new IDs further comprises computer code for recording, by the second data repository, a time stamp each time a ID related to each open LO is updated.

24. The computer program product of claim 23, wherein the I/O request comprises the ID of the currently open LO and a first timestamp of the request, the computer program product further comprising:

computer code for determining if the ID is found in the second data repository;

computer code for determining if the first timestamp is lower than a second timestamp of the ID in the second data repository;

computer code for issuing a read header request with an updated timestamp;

computer code for comparing the first timestamp and the updated ID;

computer code for repeating the issuing and comparing process until the updated timestamp is more recent then the second timestamp; and

computer code for processing the I/O request when the updated timestamp is more recent then the second timestamp.