DATA STORE SYNCHRONIZATION UTILIZING SYNCHRONIZATION LOGS

• US 20080147750A1
• Filed: 12/18/2006
• Published: 06/19/2008
• Est. Priority Date: 12/18/2006
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Zondervan, Quinton Y., Shah, Fenil, Liu, Chuang Chun, Baratham, Sesha S., Subramanian, Revathi, Auriemma, Stephen T., Corbett, Maria M.
• Granted Patent: US 10,019,501 B2
• Time in Patent Office: Days
• US Class Current: 707/202
• CPC Class Codes: G06F 16/275 Synchronous replication

Abstract

Embodiments of the present invention address deficiencies of the art in respect to data synchronization and provide a novel and non-obvious method, system and computer program product for synchronization log driven data synchronization. In one embodiment of the invention, a data synchronization method can be provided to include assembling a group of initial updates for synchronization, consulting a synchronization log of updates excluded from past synchronizations to determine updates already applied during past synchronizations, removing updates already applied during past synchronizations from a filtered set of updates, and synchronizing the filtered set of updates. In this regard, assembling a group of initial updates for synchronization can include assembling a group of initial updates having a timestamp greater than a timestamp for an immediate past synchronization.

Claims

1. A data synchronization method comprising:

assembling a group of initial updates for synchronization;

consulting a synchronization log of updates excluded from past synchronizations to determine updates already applied during past synchronizations;

removing updates already applied during past synchronizations from a filtered set of updates; and

,

synchronizing the filtered set of updates.

2. The method of claim 1, wherein assembling a group of initial updates for synchronization, comprises assembling a group of initial updates having a timestamp greater than a timestamp for an immediate past synchronization.

3. The method of claim 1, wherein consulting a synchronization log of updates excluded from past synchronizations to determine updates already applied during past synchronizations, comprises applying a synchronization filter to a difference log to identify previously unapplied updates meeting a filtering criteria.

4. The method of claim 3, further comprising removing the identified previously unapplied updates from the difference log while adding presently excluded ones of the group of updates to the difference log.

5. The method of claim 4, further comprising garbage collecting aged entries in the difference log.

6. The method of claim 1, wherein consulting a synchronization log of updates excluded from past synchronizations to determine updates already applied during past synchronizations, comprises:

receiving a peer synchronization log from a synchronization client; and

,

consulting the peer synchronization log to identify updates in the synchronization client received from peer synchronization clients.

7. The method of claim 6, wherein removing updates already applied during past synchronizations from a filtered set of updates, further comprises removing from the filtered set of updates identified updates known to have been received from peer synchronization clients.

8. The method of claim 1, wherein consulting a synchronization log of updates excluded from past synchronizations to determine updates already applied during past synchronizations, comprises:

receiving a replica table from within a peer synchronization log from a synchronization client; and

,

consulting the replica table to identify updates in the synchronization client received from peer synchronization clients that had not been updated since an immediate past synchronization.

9. The method of claim 8, wherein removing updates already applied during past synchronizations from a filtered set of updates, further comprises removing from the filtered set of updates identified updates known to have been received from peer synchronization clients that had not been updated since an immediate past synchronization.

10. The method of claim 9, further comprising garbage collecting aged entries in the peer synchronization log.

11. A peer-to-peer synchronization data processing system comprising:

a synchronization server configured for coupling to a plurality of synchronization clients configured for peer-to-peer synchronization; and

,

synchronization log based synchronization logic comprising program code enabled to track within the synchronization server updates previously applied to a selected one of the synchronization clients, to exclude from a filtered set of updates any updates already applied during past synchronizations with the selected one of the synchronization clients, and to synchronize the filtered set of updates with the selected synchronization client.

12. The system of claim 11, wherein the program code of the synchronization log based synchronization logic further is enabled to exclude from synchronization updates in the selected one of the synchronization clients that had been received in the selected one of the synchronization clients from a peer that had not been synchronized in the synchronization server since an immediate past synchronization with the selected one of the synchronization clients.

13. The system of claim 11, further comprising a garbage collector configured to garbage collect aged entries in the synchronization log.

14. A computer program product comprising a computer usable medium embodying computer usable program code for data synchronization, the computer program product comprising:

computer usable program code for assembling a group of initial updates for synchronization;

computer usable program code for consulting a synchronization log of updates excluded from past synchronizations to determine updates already applied during past synchronizations;

computer usable program code for removing updates already applied during past synchronizations from a filtered set of updates; and

,

computer usable program code for synchronizing the filtered set of updates.

15. The computer program product of claim 14, wherein the computer usable program code for assembling a group of initial updates for synchronization, comprises computer usable program code for assembling a group of initial updates having a timestamp greater than a timestamp for an immediate past synchronization.

16. The computer program product of claim 14, wherein the computer usable program code for consulting a synchronization log of updates excluded from past synchronizations to determine updates already applied during past synchronizations, comprises computer usable program code for applying a synchronization filter to a difference log to identify previously unapplied updates meeting a filtering criteria.

17. The computer program product of claim 16, further comprising computer usable program code for removing the identified previously unapplied updates from the difference log while adding presently excluded ones of the group of updates to the difference log.

18. The computer program product of claim 17, further comprising computer usable program code for garbage collecting aged entries in the difference log.

19. The computer program product of claim 14, wherein the computer usable program code for consulting a synchronization log of updates excluded from past synchronizations to determine updates already applied during past synchronizations, comprises:

computer usable program code for receiving a peer synchronization log from a synchronization client; and

,

computer usable program code for consulting the peer synchronization log to identify updates in the synchronization client received from peer synchronization clients.

20. The computer program product of claim 19, wherein the computer usable program code for removing updates already applied during past synchronizations from a filtered set of updates, further comprises computer usable program code for removing from the filtered set of updates identified updates known to have been received from peer synchronization clients.

21. The computer program product of claim 14, wherein the computer usable program code for consulting a synchronization log of updates excluded from past synchronizations to determine updates already applied during past synchronizations, comprises:

computer usable program code for receiving a replica table from within a peer synchronization log from a synchronization client; and

,

computer usable program code for consulting the replica table to identify updates in the synchronization client received from peer synchronization clients that had not been updated since an immediate past synchronization.

22. The computer program product of claim 21, wherein the computer usable program code for removing updates already applied during past synchronizations from a filtered set of updates, further comprises computer usable program code for removing from the filtered set of updates identified updates known to have been received from peer synchronization clients that had not been updated since an immediate past synchronization.

23. The computer program product of claim 22, further comprising computer usable program code for garbage collecting aged entries in the peer synchronization log.