Selective clearing of persistent metadata in a storage subsystem

• US 20060106873A1
• Filed: 11/18/2004
• Published: 05/18/2006
• Est. Priority Date: 11/18/2004
• Status: Abandoned Application

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Hsu, Yu-Cheng, Mannenbach, David F., Springer, James A., Budaya, Angelique R., Lovrien, Kurt A., Wiebe, Lloyd P.
• Application Number:
  US10/993,092
• Publication Number:
  US 20060106873A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 11/1435 using file system or storage system metadata
• CPC Class Codes: G06F 3/0605 by facilitating the interaction with a user or administrator
• CPC Class Codes: G06F 3/0614 Improving the reliability of storage systems
• CPC Class Codes: G06F 3/0652 Erasing, e.g. deleting, data cleaning, moving of data to a wastebasket
• CPC Class Codes: G06F 3/0683 Plurality of storage devices

Abstract

Method for selectively clearing persistent data such as metadata in a storage subsystem. The method includes identifying one or more metadata tracks to clear, receiving a request from a client to clear the identified metadata tracks, passing the request to a storage device driver, and clearing the identified metadata tracks. The metadata tracks to be cleared may be identified by a specific storage function associated with the metadata to be cleared or by a specific storage target associated with metadata. Alternatively, both a storage function and a storage target may be specified. Preferably, the request to clear one or more identified metadata tracks may be executed without affecting unrelated storage functions. In addition, the request may be executed while preserving metadata tracks unrelated to the identified metadata tracks. Thus, execution of a request to selectively clear identified global metadata tracks in accordance with the present invention will typically not cause the loss of configuration information and will not necessitate a reboot of the system. In addition, a request as described above may be executed at any point in time while the storage system is running.

Claims

1. A method of selectively clearing metadata in a storage subsystem comprising:

identifying one or more metadata tracks to clear;

receiving a request from a client to clear the one or more identified metadata tracks;

passing the request to a storage device driver; and

clearing the identified metadata tracks.

2. The method of claim 1 wherein identifying the metadata tracks to be cleared comprises specifying a storage function having associated metadata.

3. The method of claim 2 wherein the specified storage function is selected from a group consisting of copy functions, peer to peer remote copy functions, extended distance copy functions, point in time copy functions, and reset logical unit number functions.

4. The method of claim 1 wherein identifying the metadata tracks to be cleared comprises specifying a storage target associated with metadata.

5. The method of claim 4 wherein the specified storage target is selected from a group consisting of a logical subsystem, a logical volume, a physical storage volume, and a physical storage track.

6. The method of claim 1 further comprising notifying one or more functional storage components that a request to clear the one or more identified metadata tracks has been received.

7. The method of claim 6 further comprising determining if a select functional storage component must perform specific functions to execute the request to clear the one or more identified metadata tracks.

8. The method of claim 7 further comprising performing specific functions to execute the request to clear the one or more identified metadata tracks.

9. The method of claim 1 further comprising executing the request to clear the one or more identified metadata tracks without affecting unrelated storage functions.

10. The method of claim 1 further comprising preserving metadata tracks unrelated to the identified metadata tracks.

11. A storage subsystem comprising:

means for receiving a request from a client to clear one or more identified metadata tracks associated with the storage subsystem;

a storage device driver associated with the storage subsystem, the storage device driver comprising means for receiving the request to clear the one or more tracks of metadata; and

means for clearing the identified metadata tracks.

12. The storage subsystem of claim 11 wherein the metadata tracks to be cleared are identified by specifying a storage function having associated metadata.

13. The storage subsystem of claim 12 wherein the storage function specified to identify the metadata tracks to be cleared is selected from a group consisting of copy functions, peer to peer remote copy functions, extended distance copy functions, and point in time copy functions.

14. The storage subsystem of claim 11 wherein the metadata tracks to be cleared are identified by specifying a storage target associated with metadata.

15. The storage subsystem of claim 14 wherein the storage target specified to identify the metadata tracks to be cleared is selected from a group consisting of a logical subsystem, a logical volume, a physical storage volume, and a physical storage track.

16. The storage subsystem of claim 11 further comprising:

functional storage components associated with the storage device driver; and

means for notifying the functional storage components that a request to clear the one or more identified metadata tracks has been received.

17. The storage subsystem of claim 16 further comprising means for determining if a select functional storage component must perform specific functions to execute the request to clear the one or more identified metadata tracks.

18. The storage subsystem of claim 17 further comprising means for performing specific functions to execute the request to clear the one or more identified metadata tracks.

19. The storage subsystem of claim 11 wherein the means for clearing the identified metadata tracks does not affect unrelated storage functions.

20. The storage subsystem of claim 11 wherein the means for clearing the identified metadata tracks does not clear metadata tracks unrelated to the identified metadata tracks.

21. An article of manufacture for use in programming a data storage system to selectively clear metadata the article of manufacture comprising instructions for:

identifying one or more metadata tracks to clear;

receiving a request from a client to clear the one or more identified metadata tracks;

passing the request to a storage device driver; and

clearing the identified metadata tracks.

22. The article of manufacture of claim 21 wherein the instructions for identifying the metadata tracks to be cleared comprise instructions specifying a storage function having associated metadata.

23. The article of manufacture of claim 22 wherein the instructions specify a storage function selected from a group consisting of copy functions, peer to peer remote copy functions, extended distance copy functions, and point in time copy functions.

24. The article of manufacture of claim 21 wherein the instructions for identifying the metadata tracks to be cleared comprise instructions specifying a storage target associated with metadata.

25. The article of manufacture of claim 24 wherein the instructions specify a storage target selected from a group consisting of a logical subsystem, a logical volume, a physical storage volume, and a physical storage track.

26. The article of manufacture of claim 21 further comprising instructions for notifying one or more functional storage components that a request to clear the one or more identified metadata tracks has been received.

27. The article of manufacture of claim 26 further comprising instructions for determining if a select functional storage component must perform specific functions to execute the request to clear the one or more identified metadata tracks.

28. The article of manufacture of claim 27 further comprising instructions for performing specific functions to execute the request to clear the one or more identified metadata tracks.

29. The article of manufacture of claim 21 further comprising instructions for executing the request to clear the one or more identified metadata tracks without affecting unrelated storage functions.

30. The article of manufacture of claim 21 further comprising instructions for preserving metadata tracks unrelated to the identified metadata tracks.

31. A method for deploying a data storage infrastructure, comprising integrating computer readable code into a data storage system to selectively clear metadata in a storage subsystem wherein the code in combination with the data storage system is capable of performing the following:

identifying one or more metadata tracks to clear;

receiving a request from a client to clear the one or more identified metadata tracks;

passing the request to a storage device driver; and

clearing the identified metadata tracks.

32. The method for deploying a data storage infrastructure of claim 31 wherein the code in combination with the data storage system is further capable of identifying the metadata tracks to be cleared by specifying a storage function having associated metadata.

33. The method for deploying a data storage infrastructure of claim 32 wherein the storage function specified by the code in combination with the data storage system is selected from a group consisting of copy functions, peer to peer remote copy functions, extended distance copy functions, and point in time copy functions.

34. The method for deploying a data storage infrastructure of claim 31 wherein the code in combination with the data storage system is further capable of identifying the metadata tracks to be cleared by specifying a storage target associated with metadata.

35. The method for deploying a data storage infrastructure of claim 34 wherein the storage target specified by the code in combination with the data storage system is selected from a group consisting of a logical subsystem, a logical volume, a physical storage volume, and a physical storage track.

36. The method for deploying a data storage infrastructure of claim 31 wherein the code in combination with the data storage system is further capable of notifying one or more functional storage components that a request to clear the one or more identified metadata tracks has been received.

37. The method for deploying a data storage infrastructure of claim 36 wherein the code in combination with the data storage system is further capable of determining if a select functional storage component must perform specific functions to execute the request to clear the one or more identified metadata tracks.

38. The method for deploying a data storage infrastructure of claim 37 wherein the code in combination with the data storage system is further capable of performing specific functions to execute the request to clear the one or more identified metadata tracks.

39. The method for deploying a data storage infrastructure of claim 31 wherein the code in combination with the data storage system is further capable of executing the request to clear the one or more identified metadata tracks without affecting unrelated storage functions.

40. The method for deploying a data storage infrastructure of claim 31 wherein the code in combination with the data storage system is further capable of preserving metadata tracks unrelated to the identified metadata tracks.