Incremental data storage method, apparatus, interface, and system

• US 7,707,374 B2
• Filed: 01/02/2007
• Issued: 04/27/2010
• Est. Priority Date: 10/22/2003
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Kisley, Richard V., Mannaru, Durga Devi, Lake, John Michael
• Primary Examiner(s): Bragdon; Reginald G
• Assistant Examiner(s): Sadler; Nathan
• Application Number:
  US11/619,151
• Publication Number:
  US 20070156794A1
• Time in Patent Office: 1,211 Days
• Field of Search: 711/161
• US Class Current: 711/162
• CPC Class Codes: G06F 11/1466 to make the backup process non-disruptive
• CPC Class Codes: G06F 12/16 Protection against loss of memory contents contains no material, see G06F11/00
• CPC Class Codes: G06F 16/00 Information retrieval; Database structures therefor; File system structures therefor
• 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;

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

a compaction module configured to compact a snapshot partition, wherein the compaction module is further configured to conduct compaction as directed by a storage management policy, 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.

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, wherein the compaction module is further configured to conduct in-place compaction.

4. The apparatus of claim 1, wherein the compaction module is further configured to automatically compact a snapshot partition to a baseline volume.

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

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

7. The apparatus of claim 6, wherein the read module is further configured to retrieve the most recent data corresponding to a specified snapshot volume and block address.

8. An interface stored on computer readable medium for managing incremental data storage, the interface comprising:

a write function configured to append an entry to an incremental log by way of a processer;

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

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

a delete volume function configured to release a snapshot volume;

the delete volume function disassociating a volume identifier from the snapshot volume.

9. The interface of claim 8, further comprising a read next entry function configured to retrieve a sequential entry from the incremental log.

10. The interface of claim 8, further comprising a compact volume function configured to compact a snapshot volume.

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

appending data to an incremental log by way of a processor;

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

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

releasing a snapshot volume by disassociating a volume identifier from the snapshot volume.

12. The method of claim 11, wherein automatically assigning a volume identifier to a newly formed partition occurs as directed by a storage management policy.

13. The method of claim 11, further comprising conducting in-place compaction of a snapshot partition.

14. The method of claim 11, further comprising automatically compacting a snapshot partition.

15. 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;

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; and

a compaction module configured to compact a snapshot partition, wherein the compaction module is further configured to conduct compaction as directed by a storage management policy, 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.

16. The system of claim 15, wherein the snapshot management module is further configured to automatically compact a snapshot volume into the baseline volume in response to the snapshot operation.

17. The system of claim 15, wherein the snapshot management module is further configured to conduct in-place compaction of a snapshot partition.

18. The system of claim 15, wherein the primary storage device comprises a plurality of redundantly arranged storage devices.

19. A computer readable medium for managing incremental data storage, the computer readable medium 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; and

releasing a snapshot volume by disassociating a volume identifier from the snapshot volume.

20. The computer readable medium of claim 19, wherein the process further comprises conducting in-place compaction of a snapshot partition.

21. The computer readable medium of claim 19, wherein the process further comprises automatically assigning a volume identifier to a newly formed partition occurs as directed by a storage management policy.

22. The computer readable medium of claim 19, wherein the process further comprises automatically compacting a snapshot partition.