Method for loosely coupling metadata and data in a storage array

• US 20030204670A1
• Filed: 04/25/2002
• Published: 10/30/2003
• Est. Priority Date: 04/25/2002
• Status: Active Grant

• Current Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Original Assignee: LSI Logic Corporation (Broadcom, Inc.)
• Inventors: Delaney, William P., Holt, Keith W.
• Granted Patent: US 7,032,125 B2
• Time in Patent Office: Days
• US Class Current: 711/112
• CPC Class Codes: G06F 2003/0697 device management, e.g. handlers, drivers, I/O schedulers
• CPC Class Codes: G06F 3/0601 Interfaces specially adapted for storage systems
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0617 in relation to availability
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

The present invention is a method and system for associating metadata with user data in a storage array in a manner that provides independence between metadata management and a storage controller'"'"'s cache block size. Metadata may be associated with user data according to multiple fashions in order to provide a desired performance benefit. In one example, the metadata may be associated according to a segment basis to maximize random I/O performance and may be associated according to a stripe basis to maximize sequential I/O performance.

Claims

1. A method for configuring a storage system including a storage controller and a storage disk array, comprising:

(a) storing metadata in at least one sector of said storage disk array; and

(b) associating each sector of metadata with a related user data block according to a desired scheme to produce a memory data layout structure on said storage disk array;

wherein said at least one sector of metadata are not adjacent to said related block of user data, said desired scheme providing metadata management independence from a change in a cache block size of said storage controller of said storage system.

2. The method as claimed in claim 1, wherein said desired scheme maximizes random input/output performance of said storage system.

3. The method as claimed in claim 1, wherein said desired scheme maximizes sequential input/output performance of said storage system.

4. The method as claimed in claim 2, wherein said metadata is associated with said related user data block according to a segment basis.

5. The method as claimed in claim 3, wherein said metadata is associated with said related user data block according to a stripe basis.

6. The method as claimed in claim 1, wherein said at least one sector of metadata is stored in a separate section of said storage disk array from a section including multiple user data blocks.

7. The method as claimed in claim 1, further comprising receiving a selection of said desired scheme.

8. The method as claimed in claim 1, wherein a change of said cache block size of said storage controller does not require a change in said memory data layout structure on said storage disk array.

9. A method for configuring a storage system including a storage controller and a storage disk array, comprising:

(a) storing metadata in at least one sector of said storage disk array; and

(b) associating each sector of metadata with a related user data block according to a desired scheme to produce a memory data layout structure on said storage disk array;

wherein said at least one sector of metadata are not adjacent to said related block of user data, said desired scheme providing metadata management independence from a change in a cache block size of said storage controller of said storage system, said memory data layout structure not requiring modification upon said change in said cache block size of said storage controller.

10. The method as claimed in claim 9, wherein said desired scheme maximizes random input/output performance of said storage system.

11. The method as claimed in claim 9, wherein said desired scheme maximizes sequential input/output performance of said storage system.

12. The method as claimed in claim 10, wherein said metadata is associated with said related user data block according to a segment basis.

13. The method as claimed in claim 11, wherein said metadata is associated with said related user data block according to a stripe basis.

14. The method as claimed in claim 9, wherein said at least one sector of metadata is stored in a separate section of said storage disk array from a section including multiple user data blocks.

15. The method as claimed in claim 9, further comprising receiving a selection of said desired scheme.

16. A system for configuring a storage system including a storage controller and a storage disk array, comprising:

(a) means for storing metadata in at least one sector of said storage disk array; and

(b) means for associating each sector of metadata with a related user data block according to a desired scheme to produce a memory data layout structure on said storage disk array;

wherein said at least one sector of metadata are not adjacent to said related block of user data, said desired scheme providing metadata management independence from a change in a cache block size of said storage controller of said storage system, said memory data layout structure not requiring modification upon said change in said cache block size of said storage controller.

17. The system as claimed in claim 16, wherein said desired scheme maximizes random input/output performance of said storage system.

18. The system as claimed in claim 16, wherein said desired scheme maximizes sequential input/output performance of said storage system.

19. The system as claimed in claim 17, wherein said metadata is associated with said related user data block according to a segment basis.

20. The system as claimed in claim 18, wherein said metadata is associated with said related user data block according to a stripe basis.

21. The system as claimed in claim 16, wherein said at least one sector of metadata is stored in a separate section of said storage disk array from a section including multiple user data blocks.

22. The system as claimed in claim 16, further comprising receiving a selection of said desired scheme.