Method of automatically generating and disbanding data mirrors according to workload conditions

• US 20020133681A1
• Filed: 03/15/2001
• Published: 09/19/2002
• Est. Priority Date: 03/15/2001
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: McBrearty, Gerald Francis, Shieh, Johnny Meng-Han
• Granted Patent: US 6,961,727 B2
• Time in Patent Office: Days
• US Class Current: 711/165
• CPC Class Codes: G06F 11/2058 using more than 2 mirrored copies
• CPC Class Codes: G06F 11/2069 Management of state, configuration or failover
• CPC Class Codes: G06F 11/2082 Data synchronisation
• CPC Class Codes: Y10S 707/99932 Access augmentation or optimizing

Abstract

A method of automatically generating and decommissioning mirrors of data contained in physical storage volumes in computer system is disclosed. Physical storage volumes and portions of volumes are monitored to collect usage statistics. Those usage statistics are then used to determine whether to mirror the volume or volume portion for greater efficiency. Likewise, the usage statistics are used to determine when mirrors already generated should be decommissioned due to lack of usage.

Claims

1. A method for distributing a storage system workload in a data processing system having a plurality of storage volumes, comprising the steps of:

collecting usage statistics from the plurality of physical storage volumes;

analyzing the usage statistics to identify a hot spot on a first physical storage volume from the plurality of physical storage volumes; and

copying data from the hot spot to at least one portion of unused storage space on at least one second physical storage volume to generate a mirror of the hot spot.

2. The method of claim 1, further comprising the steps of:

receiving a request to read data from the hot spot; and

responsive to receiving the request to read, reading the data from one of the hot spot and the mirror.

3. The method of claim 2, further comprising the steps of:

receiving a request to write the data to the hot spot;

responsive to receiving the request to write, writing the data to the hot spot and to the mirror; and

disallowing execution of the reading step until the writing step has been fully completed.

4. The method of claim 1, further comprising the steps of:

receiving a request to write the data to the hot spot;

responsive to receiving the request to write, writing the data to the hot spot and to the mirror.

5. The method of claim 1, wherein the at least one second physical storage volume includes at least one shared volume, which is shared between the data processing system and at least one second data processing system.

6. The method of claim 1, wherein the at least one second physical storage volume includes at least one hot spare volume, and wherein the at least one hot spare volume is reserved to be used as a substitute device when one of the plurality of physical storage volumes fails.

7. The method of claim 6, further comprising the step of:

responsive to a failure of a third physical storage volume from the plurality of physical storage volumes, decommissioning the mirror.

8. The method of claim 1, wherein the hot spot is a mirror of a second hot spot.

9. The method of claim 1, further comprising the steps of:

identifying a period of low resource usage within the data processing system; and

scheduling the copying step to be performed during the period.

10. The method of claim 1, wherein the hot spot is identified by calculating at least one usage metric and comparing the at least one usage metric to at least one threshold value.

11. The method of claim 1, further comprising the steps of:

analyzing the usage statistics to identify an underutilized mirror stored in the plurality of physical storage volumes; and

decommissioning the underutilized mirror to free space associated with the underutilized mirror.

13. The computer program product of claim 12, further comprising instructions for:

receiving a request to read data from the hot spot; and

responsive to the receiving the request to read, reading the data from one of the hot spot and the mirror.

14. The computer program product of claim 13, further comprising instructions for:

receiving a request to write the data to the hot spot;

responsive to receiving the request to write, writing the data to the hot spot and to the mirror; and

disallowing execution of the reading step until the writing step has been fully completed.

15. The computer program product of claim 12, comprising instructions for:

receiving a request to write the data to the hot spot;

responsive to receiving the request to write, writing the data to the hot spot and to the mirror.

16. The computer program product of claim 12, wherein the at least one second physical storage volume includes at least one shared volume, which is shared between the data processing system and at least one second data processing system.

17. The computer program product of claim 12, wherein the at least one second physical storage volume includes at least one hot spare volume, and wherein the at least one hot spare volume is reserved to be used as a substitute device when one of the plurality of physical storage volumes fails.

18. The computer program product of claim 17, further comprising instructions for:

responsive to a failure of a third physical storage volume from the plurality of physical storage volumes, decommissioning the mirror.

19. The computer program product of claim 12, wherein the hot spot is a mirror of a second hot spot.

20. The computer program product of claim 12, further comprising instructions for:

identifying a period of low resource usage within the data processing system; and

scheduling the instructions for copying to be executed during the period.

21. The computer program product of claim 12, wherein the hot spot is identified by calculating at least one usage metric and comparing the at least one usage metric to at least one threshold value.

22. The computer program product of claim 12, further comprising instructions for:

analyzing the usage statistics to identify an underutilized mirror stored in the plurality of physical storage volumes; and

decommissioning the underutilized mirror to free space associated with the underutilized mirror.

24. The system of claim 23, wherein the first physical storage volume is a disk drive.

12. A computer program product, in a computer-readable medium, for distributing a storage system workload in a data processing system having a plurality of storage volumes, comprising instructions for:

collecting usage statistics from the plurality of physical storage volumes;

analyzing the usage statistics to identify a hot spot on a first physical storage volume from the plurality of physical storage volumes; and

copying data from the hot spot to at least one portion of unused storage space on at least one second physical storage volume to generate a mirror of the hot spot.

23. A system for distributing a storage system workload, comprising:

a central processing unit executing a software driver; and

a plurality of physical storage volumes in communication with the central processing unit and controlled by the software driver,

wherein the software driver collects usage statistics from the plurality of physical storage volumes, the software driver analyzes the usage statistics to find a hot spot on a first physical storage volume from the plurality of physical storage volumes, the software driver identifies at least one portion of unused storage space on at least one second physical storage volume from the plurality of physical storage volumes, and the software driver copies data from the hot spot to the at least one portion of unused storage space to generate a mirror of the hot spot.