System and method for state data back-up in a distributed data system

• US 20030167331A1
• Filed: 03/01/2002
• Published: 09/04/2003
• Est. Priority Date: 03/01/2002
• Status: Active Grant

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Kumar, Ajay, Khemani, Prakash, Susarla, Hanumantha Rao
• Granted Patent: US 7,788,346 B2
• Time in Patent Office: Days
• US Class Current: 709/227
• CPC Class Codes: G06F 11/1451 by selection of backup contents
• CPC Class Codes: G06F 11/1464 for networked environments

Abstract

A client-server system may include a distributed store configured to maintain a primary state of session data including one or more attributes. One or more other nodes may include other instances of the primary state. The system may compare the primary state to a benchmark primary state to generate a subset of the attributes of the session data that have been modified in the primary state. Another instance of the primary state may be synchronized with the primary state using the subset of the attributes. In one embodiment, the comparing may include performing binary differencing of binary representations of the primary state and the benchmark primary state to determine the modified attributes. In another embodiment, the comparing may include performing object graph differencing of object graph representations of the primary state and the benchmark primary state to determine the modified attributes.

Claims

1. A system, comprising:

a first node of a distributed store comprising a primary state of session data configured for access by a plurality of application servers, wherein the session data comprises a plurality of attributes;

another node comprising a back-up instance of the primary state;

wherein the system is configured to;

compare the primary state to a benchmark of the primary state to generate a subset of the attributes of the session data that have been modified in the primary state; and

synchronize the back-up instance of the primary state with the primary state using the subset of the attributes of the session data.

2. The system as recited in claim 1, wherein, to compare the primary state to the benchmark of the primary state, the system is further configured to perform binary differencing of a binary representation of the primary state and a binary representation of the benchmark of the primary state to determine the modified attributes.

3. The system as recited in claim 2, wherein, to perform binary differencing, one or more portions of the binary representation of the primary state are compared to corresponding portions of the binary representation of the benchmark of the primary state to determine the modified attributes.

4. The system as recited in claim 1, wherein, to compare the primary state to a benchmark of the primary state, the system is further configured to perform object graph differencing of an object graph representation of the primary state and an object graph representation of the benchmark of the primary state to determine the modified attributes.

5. The system as recited in claim 4, wherein the attributes comprise objects organized according to an object graph representation, wherein, to perform object graph differencing, one or more objects in the object graph representation of the primary state are compared to corresponding instances of objects in an object graph representation of the benchmark of the primary state to identify the modified attributes of the primary state.

6. The system as recited in claim 1, wherein the another node comprising a back-up instance of the primary state is another node of the distributed store.

7. A system comprising:

a distributed store node comprising a primary state of session data configured for access by a plurality of application servers, wherein the session data comprises a plurality of attributes;

another node comprising a back-up instance of the primary state;

wherein the system is configured to;

generate a set of the plurality of attributes that are mutable attributes for use in synchronizing the back-up instance of the primary state with the primary state; and

synchronize the back-up instance of the primary state with the primary state according to the generated set of the mutable attributes of the session data.

8. The system as recited in claim 7, wherein the system is further configured to compare the set of the mutable attributes to a benchmark of the primary state to determine a subset of the attributes of the session data that have been modified in the primary state.

9. The system as recited in claim 8, wherein, to compare the primary state to a benchmark of the primary state, the system is further configured to perform binary differencing of a binary representation of the primary state and a binary representation of the benchmark of the primary state to locate the modified attributes.

10. The system as recited in claim 8, wherein, to compare the primary state to a benchmark of the primary state, the system is further configured to perform object graph differencing of an object graph representation of the primary state and an object graph representation of the benchmark of the primary state to locate the modified attributes.

11. A system comprising:

a distributed store node comprising a primary state of session data configured for access by a plurality of application servers, wherein the session data comprises a plurality of attributes;

another node comprising another instance of the primary state;

means for determining a set of the attributes of the session data that differ between the primary state and the other instance of the primary state; and

means for synchronizing the other instance of the primary state with the primary state using the set of the attributes of the session data that differ between the primary state and the other instance of the primary state.

12. The system as recited in claim 11, wherein the means for determining a set of the attributes comprise comparing the primary state to a benchmark of the primary state to determine attributes of the session data that have been modified in the primary state.

13. The system as recited in claim 12, wherein, to compare the primary state to a benchmark of the primary state, the means further comprise performing binary differencing of a binary representation of the primary state and a binary representation of the benchmark of the primary state to locate the modified attributes.

14. The system as recited in claim 12, wherein, to compare the primary state to a benchmark of the primary state, the means further comprise performing object graph differencing of an object graph representation of the primary state and an object graph representation of the benchmark of the primary state to locate the modified attributes.

15. A method comprising:

providing access to a primary state of session data comprised by a distributed store node to a plurality of application servers, wherein the session data comprises a plurality of attributes;

comparing the primary state to a benchmark of the primary state to generate a subset of the attributes of the session data that have been modified in the primary state; and

synchronizing the another instance of the primary state comprised by another node with the primary state using the subset of the attributes of the session data.

16. The method as recited in claim 15, wherein said comparing the primary state to a benchmark of the primary state comprises performing binary differencing of a binary representation of the primary state and a binary representation of the benchmark of the primary state to determine the modified attributes.

17. The method as recited in claim 16, wherein performing binary differencing comprises comparing one or more portions of the binary representation of the primary state to corresponding portions of the binary representation of the benchmark of the primary state to determine the modified attributes.

18. The method as recited in claim 15, wherein said comparing the primary state to a benchmark of the primary state comprises performing object graph differencing of an object graph representation of the primary state and an object graph representation of the benchmark of the primary state to determine the modified attributes.

19. The method as recited in claim 18, wherein the attributes comprise objects organized according to an object graph representation, wherein performing object graph differencing comprises comparing one or more objects in the object graph representation of the primary state to corresponding instances of objects in an object graph representation of the benchmark of the primary state to identify the modified attributes of the primary state.

20. The method as recited in claim 15, wherein the other instance of the primary state is a backup of the primary state.

21. An article of manufacture comprising software instructions executable to implement:

providing access to a primary state of session data comprised by a distributed store node to a plurality of application servers, wherein the session data comprises a plurality of attributes;

comparing the primary state to a benchmark of the primary state to generate a subset of the attributes of the session data that have been modified in the primary state; and

synchronizing the another instance of the primary state comprised by another node with the primary state using the subset of the attributes of the session data.

22. The article of manufacture as recited in claim 21, wherein said comparing the primary state to a benchmark of the primary state comprises performing binary differencing of a binary representation of the primary state and a binary representation of the benchmark of the primary state to determine the modified attributes.

23. The article of manufacture as recited in claim 22, wherein said performing binary differencing comprises comparing one or more portions of the binary representation of the primary state to corresponding portions of the binary representation of the benchmark of the primary state to determine the modified attributes.

24. The article of manufacture as recited in claim 21, wherein said comparing the primary state to a benchmark of the primary state comprises performing object graph differencing of an object graph representation of the primary state and an object graph representation of the benchmark of the primary state to determine the modified attributes.

25. The article of manufacture as recited in claim 24, wherein the attributes comprise objects organized according to an object graph representation, wherein said performing object graph differencing comprises comparing one or more objects in the object graph representation of the primary state to corresponding instances of objects in an object graph representation of the benchmark of the primary state to identify the modified attributes of the primary state.

26. The article of manufacture as recited in claim 21, wherein the other instance of the primary state is a backup of the primary state.