Method and apparatus for providing a dynamic quality of service for serving file/block I/O

• US 20040225736A1
• Filed: 05/06/2003
• Published: 11/11/2004
• Est. Priority Date: 05/06/2003
• Status: Abandoned Application

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Raphael, Roger C.
• Application Number:
  US10/430,554
• Publication Number:
  US 20040225736A1
• Time in Patent Office: Days
• US Class Current: 709/226
• CPC Class Codes: G06F 16/10 File systems; File servers
• CPC Class Codes: H04L 67/06 specially adapted for file transfer, e.g. file transfer protocol [FTP]
• CPC Class Codes: H04L 67/61 taking into account QoS or priority requirements
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A method and apparatus are provided for dynamically improving the quality of service in a file or block serving system through assessing initial service quality, altering the service grade or priority of a selected resource handle, assessing a modified service quality impacted by that alteration of the resource handle service grade, and adjusting the resource handle service grade in response to the modified service quality. Alteration of the service grade may be achieved through intentionally imposing latency on the transactions associated with the selected resource handle. Alternately, the service grade alteration may result from randomly changing the priority ranking or service priority of the selected resource handle, thereby impacting the processing of the I/O transactions. The method and apparatus may be implemented at the back, or service end, of the system within the data storage sub-system, independent from and transparent to host and network awareness.

Claims

1. A method for improving service quality within a data storage system, the method comprising:

altering a service grade associated with a selected resource handle;

assessing a change in service quality for the data storage system; and

adjusting the service grade for the selected resource handle in response to the change in service quality.

2. The method of claim 1, wherein altering the service grade comprises altering a service latency.

3. The method of claim 1, wherein altering the service grade comprises altering a service priority.

4. The method of claim 1, wherein assessing the change in service quality comprises computing an arrival rate for an active resource handle in the data storage system.

5. The method of claim 1, wherein adjusting the service grade comprises adjusting a service priority.

6. The method of claim 1, wherein the selected resource handle comprises a file handle.

7. The method of claim 1, wherein the selected resource handle comprises a block logical unit number (LUN).

8. The method of claim 1, further comprising providing a service queue corresponding to the service grade.

9. The method of claim 1, further comprising initializing the service grade to a selected grade, and initializing the service grade to a default grade if the selected grade is unavailable.

10. The method of claim 1, wherein improving service quality within a data storage system is conducted in a manner that is transparent to a host.

11. A method for improving service quality within a data storage system that is connected to a host, wherein the method is conducted in a manner that is transparent to the host, the method comprising:

altering a service grade associated with a selected resource handle;

assessing a change in service quality for the data storage system;

adjusting the service grade for the selected resource handle in response to the change in service quality;

providing a service queue corresponding to the service grade; and

initializing the service grade to a selected grade, and initializing the service grade to a default grade if the selected grade is unavailable.

12. An apparatus for improving service quality within a data storage system, the apparatus comprising:

an alteration module configured to alter a service grade associated with a selected resource handle;

an assessment module configured to assess a change in service quality for the data storage system; and

an adjustment module configured to adjust the service grade for the selected resource handle in response to the change in service quality.

13. The apparatus of claim 12, further comprising a latency alteration module configured to alter a service latency.

14. The apparatus of claim 12, further comprising a priority alteration module configured to alter a service priority.

15. The apparatus of claim 12, further comprising an arrival rate module configured to compute an arrival rate for an active resource handle in for the data storage system.

16. The apparatus of claim 12, further comprising a priority adjustment module configured to adjust a service priority.

17. The apparatus of claim 12, wherein the selected resource handle comprises a file handle.

18. The apparatus of claim 12, wherein the selected resource handle comprises a block logical unit number (LUN).

19. The apparatus of claim 12, further comprising a service queue module configured to provide a service queue corresponding to the service grade.

20. The apparatus of claim 12, further comprising an initialization module configured to initialize the service grade to a selected grade, and to initialize the service grade to a default grade if the selected grade is unavailable.

21. The apparatus of claim 12, wherein improving service quality within a data storage system is conducted in a manner that is transparent to a host.

22. An apparatus for improving service quality within a data storage system and conducted in a manner that is transparent to a host, the apparatus comprising:

an alteration module configured to alter a service grade associated with a selected resource handle;

an assessment module configured to assess a change in service quality for the data storage system;

an adjustment module configured to adjust the service grade for the selected resource handle in response to the change in service quality;

a service queue module configured to provide a service queue corresponding to the service grade;

an initialization module configured to initialize the service grade to a selected grade, and to initialize the service grade to a default grade if the selected grade is unavailable

23. A system for improving service quality within a data storage system, the system comprising:

a data storage subsystem;

an optimization module configured to improve service quality within the data storage sub-system, the optimization module comprising;

an alteration module configured to alter a service grade associated with a selected resource handle;

an assessment module configured to assess a change in service quality for the data storage system; and

an adjustment module configured to adjust the service grade for the selected resource handle in response to the change in service quality; and

a network configured to provide a communications means between the data storage sub-system and a client.

24. A data storage sub-system for improving performance of resource handle transactions within a network data storage sub-system, the data storage sub-system comprising:

a service queue module configured to provide a service queue and to queue the resource handle transactions;

an optimization module configured to adjust a service priority associated with a resource handle within the data storage sub-system;

the optimization module further configured to assess a change in service quality for the data storage sub-system; and

the service queue module further configured to direct the resource handle transactions to the service queue.

25. A computer readable medium comprising computer code configured to carry out a method for improving service quality within a data storage system, the method comprising:

altering a service grade associated with a selected resource handle;

assessing a change in service quality for the data storage system;

adjusting the service grade for the selected resource handle in response to the change in service quality;

26. The computer readable medium of claim 25, wherein altering the service grade comprises altering a service latency.

27. The computer readable medium of claim 25, wherein altering the service grade comprises altering a service priority.

28. The computer readable medium of claim 25, wherein assessing the change in service quality comprises computing an arrival rate for an active resource handle in the data storage system.

29. The computer readable medium of claim 25, wherein adjusting the service grade comprises adjusting a service priority.

30. The computer readable medium of claim 25, wherein the selected resource handle comprises a file handle.

31. The computer readable medium of claim 25, wherein the selected resource handle comprises a block logical unit number (LUN).

32. The computer readable medium of claim 25, wherein the method further comprises providing a service queue corresponding to the service grade.

33. The computer readable medium of claim 25, wherein the method further comprises initializing the service grade to a selected grade, and initializing the service grade to a default grade if the selected grade is unavailable.

34. The computer readable medium of claim 25, wherein the method is conducted in a manner that is transparent to a host.

35. An apparatus for improving service quality within a data storage system and conducted in a manner that is transparent to a host, the apparatus comprising:

means for altering a service grade associated with a selected resource handle;

means for assessing a change in service quality for the data storage system;

means for adjusting the service grade for the selected resource handle in response to the change in service quality;

means for providing a service queue corresponding to the service grade; and

means for initializing the service grade to a selected grade, and initializing the service grade to a default grade if the selected grade is unavailable.