Recovery point data view shift through a direction-agnostic roll algorithm

• US 20070282921A1
• Filed: 05/22/2006
• Published: 12/06/2007
• Est. Priority Date: 05/22/2006
• Status: Active Grant

• Current Assignee: InMage Systems, Inc. (Microsoft Corporation)
• Original Assignee: InMage Systems, Inc. (Microsoft Corporation)
• Inventors: Atluri, Rajeev, Shah, Jayesh, Kumar, Srin, Pannerselvam, Sudhakar, Kumar, Satish, Paygude, Kishor
• Granted Patent: US 7,676,502 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 11/1471 involving logging of persistent data for recovery
• CPC Class Codes: G06F 2201/80 Database-specific techniques
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data
• CPC Class Codes: Y10S 707/99953 Recoverability

Abstract

A method and system of recovery point data view shift through a direction-agnostic roll algorithm is disclosed. In one embodiment, a method includes forming a data view around a recovery point, and shifting the data view around the recovery point through a direction-agnostic roll algorithm that uses at least one of a roll-forward algorithm to shift the data view to a time before the recovery point and a roll-backward algorithm to shift the data view to a time before the recover point. A data integrity may be determined to be consistent at the recover point by examining data and meta-data associated with the recovery point. The recovery point may be associated with at least one of an automatically generated event, a user definable event, and a prepackaged event. A marker data may be generated at the recovery point to enable the direction-agnostic roll algorithm to reduce a recovery time objective when an algorithm is applied.

Claims

1. A method comprising:

forming a data view around a recovery point; and

shifting the data view around the recovery point through a direction-agnostic roll algorithm that uses at least one of a roll-forward algorithm to shift the data view to a time after the recovery point and a roll-backward algorithm to shift the data view to a time before the recover point.

4. The method of claim 1 further comprising generating a marking data at the recovery point to enable the direction-agnostic roll algorithm to operate and to reduce a recovery time objective when an algorithm is applied.

5. The method of claim 1 wherein data adjacent to the recovery point is maintained in a log data structure that is stored in a file system as a multitude of files.

6. The method of claim 1 further comprising coalescing data around the recovery point and other determinable recovery points at a threshold interval to reduce storage requirements.

8. The method of claim 1 in a form of a machine-readable medium embodying a set of instructions that, when executed by a machine, causes the machine to perform the method of claim 1.

2. The method of claim 2 further comprising determining that a data integrity is consistent at the recover point by examining data and meta-data associated with the recovery point.

3. The method of claim 3 further comprising associating the recovery point with at least one of an automatically generated event, a user definable event, and a prepackaged event.

7. The method of claim 7 further comprising retaining differing quantities of data around the recovery point based on a programmatic methodology that considers space utilization and a data consistency associated with the time after the recovery point and the time before the recovery point.

9. A method comprising:

generating a recovery snapshot at a predetermined interval to retain an ability to position forward and backward when a delayed roll back algorithm is applied;

and creating a virtual view of the recovery snapshot using an algorithm tied to an original data, a change log data, and a consistency data related to an event.

10. The method of claim 9 further comprising redirecting an access request to the original data based on a meta-data information provided in the virtual view.

11. The method of claim 10 further comprising substantially retaining a timestamp data, a location of a change, and a time offset of the change as compared with the original data.

12. The method of claim 9 further comprising utilizing a relational database to process the change log data in a meta-data format, and to process other on-disk data using a binary-tree format.

13. The method of claim 9 wherein the virtual view is specific to a volume object in a kernel that imitates another volume having the original data.

14. The method of claim 13 wherein the virtual view is managed by a kernel space that processes an access request through at least one table using a meta-data created in a retention log.

15. The method of claim 9 further comprising exporting the virtual view as a virtual volume using at least one of an iSCSI and a fiber channel transport to an external processing device.

16. The method of claim 9 wherein the change log data is applied when the virtual view is unfrozen after a user session reaches a level state.

17. The method of claim 9 further comprising:

generating a series of indexes of the virtual view to enable a linking to an event description of the virtual view rather than to an actual data in the original data; and

automatically creating the virtual view in at least one of a scheduled and an event driven manner.

18. A network, comprising:

a virtualization module to form a data view around a recovery point;

a recovery module to generate a recovery snapshot having an ability to position forward and backward from the recovery point when a rolling algorithm is applied; and

an events module to generate a coalesce policy around the recovery point to reduce a storage requirement.

19. The network of claim 18 further comprising an export module to transfer the data view to an external processing device as a virtual volume using at least one of an iSCSI and a fiber channel transport interface.

20. The network of claim 19 wherein the export module automatically communicates the data view to a backup tape to provide extended data retention using a lifecycle management policy.

21. A method comprising:

determine a temporal window based on at least one of a user data and an automatically generated data;

coalescing data between events prior to the temporal window; and

capturing data between events after the temporal window.

22. The method of claim 21 wherein the coalescing data between events prior to the temporal window is determined by a set of overlapping operations to a data set, wherein certain operations have non-overlapping sectors which are not coalesced.

23. The method is claim 21 further comprising shifting the data view around a recovery point through a direction-agnostic roll algorithm that uses at least one of a roll-forward algorithm to shift the data view to a time after the recovery point and a roll-backward algorithm to shift the data view to a time before the recover point.