Incremental data storage method, apparatus, interface, and system

• US 20050091461A1
• Filed: 10/22/2003
• Published: 04/28/2005
• Est. Priority Date: 10/22/2003
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Lake, John Michael, Kisley, Richard V., Mannaru, Durga Devi
• Granted Patent: US 7,171,538 B2
• Time in Patent Office: Days
• US Class Current: 711/162
• CPC Class Codes: G06F 11/1466 to make the backup process non-disruptive
• CPC Class Codes: G06F 16/10 File systems; File servers
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data

Abstract

An interface for managing incremental data storage includes a write function that appends an entry to an incremental log, a read function that retrieves a most recent log entry corresponding to a block address, and a snapshot function that automatically partitions the incremental log into an additional volume. The interface may also include a policy assignment function that associates specified policies with explicitly or implicitly specified resources, a read entry function that retrieves sequential entries from the incremental log, and a compact volume function. The provided functions and associated apparatus, method, and system, facilitate management of incremental data including snapshot, remote copy, data compaction, policy management, data restoration, and other operations on data storage devices and systems.

Claims

1. An apparatus for incremental data storage, the apparatus comprising:

a baseline partition containing a baseline image;

an incremental log configured to store data, the incremental log comprising at least one snapshot partition; and

a partition module configured to automatically partition the incremental log into an additional snapshot partition in response to a snapshot operation.

2. The apparatus of claim 1, wherein the partition module is further configured to assign a volume identifier to a newly formed partition as directed by a storage management policy.

3. The apparatus of claim 1, further comprising a storage management module configured to support storage management policies selected from the group consisting of temporal-based policies, status-based policies, and event-based policies.

4. The apparatus of claim 1, further comprising a compaction module configured to compact a snapshot partition.

5. The apparatus of claim 4, wherein the compaction module is further configured to conduct compaction as directed by a storage management policy.

6. The apparatus of claim 5, wherein the storage management policy is selected from the group consisting of a temporal-based policy, a status-based policy, and an event-based policy.

7. The apparatus of claim 4, wherein the compaction module is further configured to conduct in-place compaction.

8. The apparatus of claim 4, wherein the compaction module is further configured to automatically compact a snapshot partition to the baseline volume.

9. The apparatus of claim 1, further comprising a copy module configured to copy selected log entries to the tertiary volume.

10. The apparatus of claim 1, further comprising a read module configured to retrieve the most recent data corresponding to a block address.

11. The apparatus of claim 1, wherein the read module is further configured to retrieve the most recent data corresponding to a specified snapshot volume and block address.

13. The interface of claim 9, further comprising a policy assignment function configured to assign a policy to an incremental log.

14. The interface of claim 9, further comprising a read next entry function configured to retrieve a sequential entry from the incremental log.

15. The interface of claim 9, further comprising a compact volume function configured to compact a snapshot volume.

16. The interface of claim 9, further comprising a delete volume function configured to release a snapshot volume.

12. An interface for managing incremental data storage, the interface comprising:

a write function configured to append an entry to an incremental log;

a read function configured to retrieve a most recent log entry corresponding to a block address; and

a snapshot function configured to automatically partition the incremental log into a first and a second volume.

17. A method for managing incremental data storage, the method comprising:

appending data to an incremental log;

automatically partitioning the incremental log in response to a snapshot operation; and

automatically assigning a volume identifier to a newly formed partition.

18. The method of claim 17, wherein automatically assigning a volume identifier to a newly formed partition occurs as directed by a storage management policy.

19. The method of claim 17, further comprising conducting in-place compaction of a snapshot partition.

20. The method of claim 17, further comprising automatically compacting a snapshot partition.

21. An apparatus for managing incremental data storage, the apparatus comprising:

means for appending data to an incremental log;

means for automatically partitioning the incremental log in response to a snapshot operation;

means for automatically assigning a volume identifier to a newly formed partition; and

means for conducting in-place compaction of a snapshot partition.

22. A system for redundant incremental data storage, the system comprising:

a primary storage device configured to store data;

a secondary storage device configured to store data within a baseline volume and an incremental log comprising at least one snapshot partition that corresponds to a snapshot volume;

a controller configured to store and access data on the primary and secondary storage device; and

a snapshot management module configured to automatically partition the incremental log into an additional snapshot partition and associate the additional snapshot partition with a volume identifier in response to a snapshot operation.

23. The system of claim 22, wherein the snapshot management module is further configured to automatically compact a snapshot volume into the baseline volume in response to the snapshot operation.

24. The system of claim 22, wherein the snapshot management module is further configured to conduct in-place compaction of a snapshot partition.

25. The system of claim 22, wherein the primary storage device comprises a plurality of redundantly arranged storage devices.

26. A computer readable image for managing incremental data storage, the computer readable image comprising program code configured to conduct a process comprising:

append data to an incremental log;

automatically partition the incremental log in response to a snapshot operation; and

automatically assign a volume identifier to a newly formed partition.

27. The computer readable image of claim 26, wherein the process further comprises conducting in-place compaction of a snapshot partition.

28. The computer readable image of claim 26, wherein the process further comprises automatically assigning a volume identifier to a newly formed partition occurs as directed by a storage management policy.

29. The computer readable image of claim 26, wherein the process further comprises conducting in-place compaction of a snapshot partition.

30. The computer readable image of claim 26, wherein the process further comprises automatically compacting a snapshot partition.