Partial migration of an object to another storage location in a computer system

• US 20050097126A1
• Filed: 12/10/2004
• Published: 05/05/2005
• Est. Priority Date: 08/24/2000
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Cabrera, Luis Felipe, Steiner, Stefan R., Pudipeddi, Ravisankar, Jones, Deborah C.
• Granted Patent: US 7,072,914 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/10 File systems; File servers
• CPC Class Codes: Y10S 707/966 Distributed
• CPC Class Codes: Y10S 707/99931 Database or file accessing
• CPC Class Codes: Y10S 707/99954 Version management

Abstract

A technique is provided whereby a stream of data located in a first storage location is registered for migration administration and according to preset criteria, portion(s) of the stream of data that are suited to another storage location are migrated to maximize system storage efficiencies. The file system may have use of facilities that enable the monitoring of files/streams that have been registered for migration administration or files/streams may be polled according to preset criteria. If the stream of data has portions to migrate to another storage location, the hierarchical storage management (HSM) system migrates the data to the other storage location, such as to long term or off-line storage, and preserves the data relationships of the stream via metadata. The technique allows for multiple volumes to be spanned by the migration target location, and multiple file systems may service the source and target.

Claims

1. A method for migrating a portion of a stream of data having associated file system metadata via a file system from a first storage location to a second storage location in a computer system, comprising:

identifying at least one portion of the stream of data for migration to the second storage location;

migrating said at least one portion to said second storage location, wherein said migrating comprises;

(A) relocating said at least one portion from the first storage location to the second location and

(B) generating additional file system metadata relating to said stream of data.

2. A method according to claim 1, wherein said first storage location and said second storage location are located on different volumes.

3. A method according to claim 1, wherein said identifying of said at least one portion for migration includes identifying said at least one portion according to pre-set criteria.

4. A method according to claim 3, wherein said identifying of said at least one portion for migration includes specifying the size of an archive unit.

5. A method according to claim 3, wherein said identifying of said at least one portion for migration includes specifying the size of a region of updates.

6. A method according to claim 3, wherein said identifying of said at least one portion for migration includes specifying a memory allocation limit for the stream of data applicable to said first storage location.

7. A method according to claim 6, wherein said moving of said at least one portion is performed without exceeding said memory allocation limit.

8. A method according to claim 1, wherein the stream of data has at least one identifiable region of updates.

9. A method according to claim 1, wherein said identifying of said at least one portion for migration includes identifying a type of stream of data.

10. A method according to claim 9, wherein said type of stream of data is an append-only file.

11. A method according to claim 9, wherein said type of stream of data is a first storage block write only file.

12. A method according to claim 1, wherein said second storage location is a sequential access medium (SAM).

13. A method according to claim 1, wherein said first storage location is a local location and said second storage location is a remote location.

14. A method according to claim 1, wherein said first storage location is a non-secure storage location and said second storage location is a secure storage location.

15. A method according to claim 1, wherein said first storage location is an on-line location and said second storage location is an off-line location.

16. A method according to claim 1, wherein said preserving the data relationships of said stream includes generating metadata for description of said relationships.

17. A method according to claim 16, wherein said metadata for description of said relationships is formatted according to a scriptable interface capable of being incorporated into World Wide Web components.

18. A method according to claim 16, wherein said metadata for description of said relationships is formatted according to at least one of extensible markup language (XML), distributed component object model (DCOM) and Java.

19. A method according to claim 1, wherein the storage for said at least one portion in said first storage location is freed for use by the system after said at least one portion is moved to said second storage location.

20. A computer-readable medium having computer-executable instructions for instructing a computer to perform the method recited in claim 1.

21. A method of maintaining migration information for partially migrated files comprising:

defining a relationship between file system metadata and a location of the file'"'"'s remote data extents; and

utilizing the defined relationship to preserve data relationships between a migrated part and an unmigrated part of the partially migrated file.

22. The method of claim 21 wherein the file system metadata is used to describe attributes of a file and the file'"'"'s location within a volume.

23. A computer-readable medium having a computer program thereon for instructing a computer to perform the method recited in claim 21.

24. A method of re-assembling a partially migrated stream of data comprising:

ensuring all fractions of the partially migrated stream that have been migrated are immutable; and

re-assembling the fractions of the partially migrated stream without verifying whether the data represented thereby is still valid.

25. The method of claim 24 further comprising utilizing previously generated additional file system metadata relating to said stream of data to re-assemble the fractions.

26. A computer-readable medium having a computer program thereon for instructing a computer to perform the method recited in claim 24.

27. A method of storing data comprising:

receiving at a storage location a migrated portion;

of a partially migrated data stream wherein additional file system metadata relating to said stream of data had been generated due to said migration and wherein data relationships of said data stream had been preserved; and

storing at the storage location the migrated portion of the partially migrated data stream.

28. A computer-readable medium having a computer program thereon for instructing a computer to perform the method recited in claim 27.

29. A method of handling data having associated file system metadata for partial migration via a file system from a first storage location to a second storage location in a computer system comprising:

identifying at least one portion of a stream of data for migration to the second storage location; and

generating additional file system metadata relating to said stream of data for said partial migration in order to preserve data relationships of said data stream.

30. A method according to claim 29, wherein said first storage location and said second storage location are located on different volumes.

31. A method according to claim 29, wherein said identifying of said at least one portion for migration includes identifying said at least one portion according to pre-set criteria.

32. A method according to claim 29, wherein said identifying of said at least one portion for migration includes specifying the size of an archive unit.

33. A method according to claim 32, wherein said identifying of said at least one portion for migration includes specifying the size of a region of updates.

34. A method according to claim 32, wherein said identifying of said at least one portion for migration includes specifying a memory allocation limit for the stream of data applicable to said first storage location.

35. A computer-readable medium having a computer program thereon for instructing a computer to perform the method recited in claim 29.