Data storage array apparatus, method of controlling access to data storage array apparatus, and program and medium for data storage array apparatus

• US 6,564,295 B2
• Filed: 09/20/2001
• Issued: 05/13/2003
• Est. Priority Date: 09/20/2000
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Migita, Manabu, Okabayashi, Ichiro
• Primary Examiner(s): Yoo, Do Hyun
• Assistant Examiner(s): Chace, Christian P.
• Application Number:
  US09/956,685
• Publication Number:
  US 20020035670A1
• Time in Patent Office: 600 Days
• Field of Search: 711/111, 711/112, 711/114, 711/147, 711/150, 711/151, 711/152, 711/154, 711/156, 711/163, 711/167, 711/217
• US Class Current: 711/114
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 11/1088 Reconstruction on already foreseen single or plurality of spare disks
• CPC Class Codes: G06F 3/0611 in relation to response time
• CPC Class Codes: G06F 3/0614 Improving the reliability of storage systems
• CPC Class Codes: G06F 3/0653 Monitoring storage devices or systems
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

The data storage array apparatus having a RAID configuration according to the present invention comprises an internal access issuance part 10 which issues internal access requests to data storage parts 6, a group response monitoring part 11 which monitors processing responses in the data storage parts 6 until an internal access requesting group satisfies a predetermined condition and issues a notice of completion of monitoring, an external access response part 12 which notifies to outside of completion of external access in response to a predetermined situation, a continuous response monitoring part 13 which further continuously monitors, based on the notice of completion of monitoring, processing responses for each HDD with respect to an internal access request which was met with no processing response from the data storage parts, and an array operation control part 14 which controls, based on continuous response monitoring information from the continuous response monitoring part, issuance of internal accesses to the respective data storage parts.

Claims

1. A data storage array apparatus which comprises a plurality of data storage parts which store transferred data in accordance with a predetermined rule, an access issuance part, a group response monitoring part, an access response part, a continuous response monitoring part and an array operation control part, comprising:

said access issuance part, by means of a predetermined algorithm, groups first access requests from a sender of said data into a group which includes second access requests directed to said more than one data storage parts, treats said group as a second access requesting group, and issues said second access requests included in said second access requesting group to said data storage parts based on access issuance control provided to said data storage parts by said array operation control part,

said group response monitoring part individually manages each said second access requesting group, monitors processing responses, in said data storage parts, of said second access requesting group until said second access requesting group satisfies a predetermined condition, and issues a notice of completion of monitoring when said condition is satisfied,

said access response part notifies said sender of said data of completion of accessing in response to a predetermined situation,

said continuous response monitoring part classifies, for each data storage part, said second access requests of said second access requesting group which were met with no processing response from the data storage parts and further continuously monitors whether there are corresponding processing responses based on said notice of completion of monitoring thus issued, and issues a result of the monitoring as continuous response monitoring information,

said array operation control part provides access issuance control for said data storage parts to said access issuance part based on said continuous response monitoring information thus issued, so that an operation mode of said data storage array apparatus as a whole is controlled.

2. The data storage array apparatus according to claim 1, wherein said access response part notifies said sender of said data of completion of accessing based on said notice of completion of monitoring from said group response monitoring part.

3. The data storage array apparatus according to claim 1, wherein said access response part notifies said sender of said data of completion of accessing based on a notice of issuance from said access issuance part.

4. The data storage array apparatus according to claim 1, wherein during reading, based on said notice of completion of monitoring from said group response monitoring part, said access response part restores, using redundancy, data (1) for which there was no processing response, in said data storage parts, of said second access requesting group, or (2) for which there was an error response, or (3) for which issuance of second access requests were suppressed in said access issuance part, and said access response part notifies said sender of said data of completion of accessing.

8. The data storage array apparatus according to any one of claims 1 through 7, wherein there are as many said continuous response monitoring parts as said data storage parts.

9. The data storage array apparatus according to any one of claims 1 through 7, wherein said array operation control part investigates, based on said continuous response monitoring information from said continuous response monitoring part, the number of said second access requests to which processing has not completed, and when this number reaches or exceeds a certain number, said array operation control part prohibits issuance of said second access requests to corresponding ones of said data storage parts.

10. The data storage array apparatus according to any one of claims 1 through 7, wherein said array operation control part stores the number of times said continuous response monitoring part has executed continuous response monitoring, and when this number reaches or exceeds a certain number, said array operation control part shifts said data storage array apparatus into an operation of degeneration.

11. The data storage array apparatus according to claim 9, wherein said array operation control part, after prohibiting issuance of said second access requests, shifts the entire operation of said data storage array apparatus into an operation of temporary degeneration,

and said temporary degeneration is an operation that issuance of said second access requests directed to one or more of said data storage parts which form said data storage array apparatus is temporarily suppressed, and with respect to an access occurring during this, access data are restored utilizing a redundant configuration.

12. The data storage array apparatus according to any one of claims 1 through 7, wherein said array operation control part investigates, based on said continuous response monitoring information from said continuous response monitoring part, the number of said second access requests to which processing has not completed, and when this number is equal to or smaller than a certain number, said array operation control part lifts the prohibition of issuance of said second access requests to corresponding ones of said data storage parts.

13. The data storage array apparatus according to claim 12, wherein said array operation control part, after resolving the prohibition of issuance of said second access requests, shifts the entire operation of said data storage array apparatus from temporary degeneration into normal or partial reconstruction,

and an operation of said partial reconstruction is an operation of adding redundancy of data to writing which occurs during said temporary degeneration.

14. The data storage array apparatus according to any one of claims 1 through 7, wherein when recognizing based on said continuous response monitoring information that said second access requests under monitoring are not completed yet even after a predetermined period of time, said array operation control part prohibits issuance of said second access requests to corresponding ones of said data storage parts and issues a reset command or a cancel command to corresponding ones of said data storage parts.

15. The data storage array apparatus according to claim 14, wherein when said array operation control part issues said reset command, said array operation control part lifts the prohibition of issuance of said second access requests to corresponding ones of said data storage parts upon normal completion of said reset command and shifts the entire operation of said data storage array apparatus from temporary degeneration into normal or partial reconstruction.

16. The data storage array apparatus according to claim 14, wherein after said array operation control part issues said reset command, if said reset command ends abnormally, said array operation control part issues said reset command once again to corresponding ones of said data storage parts.

17. The data storage array apparatus according to claim 14, wherein the number of times that said array operation control part has issued said reset command is stored, and when this number becomes a certain number or larger, said data storage array apparatus is shifted into an operation of degeneration from an operation of temporary degeneration.

18. The data storage array apparatus according to claim 14, wherein said array operation control part recognizes based on said continuous response monitoring information a response which indicates that said second access requests under monitoring have completed during said predetermined period of time, and if these requests are writing, said array operation control part deletes corresponding requests from said access error storage part.

19. The data storage array apparatus according to claim 1 or 5, wherein said predetermined condition is satisfied (1) when N−

1 pieces of said second access requests are met with responses which indicate completion of processing in the case that there are N pieces of said second access requests included in said second access requesting group, or (2) when a predetermined period of time has elapsed after issuance of said second access requests which are included in said second access requesting group.

22. A program for making a computer function as all or part of said parts except for said data storage parts of the data storage array apparatus according to claim 1 or 5.

24. A medium which can be read on a computer and holds a program and/or data for making a computer execute the functions of all or part of said parts except for said data storage parts of the data storage array apparatus according to claim 1 or 5.

5. A data storage array apparatus which comprises a plurality of data storage parts which store transferred data in accordance with a predetermined rule, an access issuance part, a group response monitoring part, an access error storage part, an access response part, a continuous response monitoring part and an array operation control part, comprising:

said access issuance part, by means of a predetermined algorithm, groups first access requests from a sender of said data into a group which includes second access requests to said more than one data storage parts, treats said group as a second access requesting group, and issues said second access requests included in said second access requesting group to said data storage parts based on access issuance control provided to said data storage parts by said array operation control part and based on a content in said access error storage part which stores an error status of a previously issued external access,

said group response monitoring part individually manages each said second access requesting group, monitors processing responses in said data storage parts directed to said second access requesting group until said second access requesting group satisfies a predetermined condition, and issues a notice of completion of monitoring when said condition is satisfied,

said access error storage part registers, based on said notice of completion of monitoring thus issued, accesses (1) for which there was no processing response, in said data storage parts, of said second access requesting group or for which there was an error response, or (2) for which issuance of second access requests were suppressed in said access issuance part,

said access response part notifies said sender of said data of completion of accessing in response to a predetermined situation,

said continuous response monitoring part classifies, for each data storage part, said second access requests of said second access requesting group which were met with no processing response from the data storage parts and further continuously monitors whether there are corresponding processing responses based on said notice of completion of monitoring thus issued, and issues a result of the monitoring as continuous response monitoring information,

said array operation control part provides access issuance control for said data storage parts to said access issuance part based on said continuous response monitoring information thus issued, so that an operation mode of said data storage array apparatus as a whole is controlled.

6. The data storage array apparatus according to claim 5, wherein said access response part notifies said sender of said data of completion of accessing based on said notice of completion of monitoring from said group response monitoring part.

7. The data storage array apparatus according to claim 5, wherein said access response part notifies said sender of said data of completion of accessing based on a notice of issuance from said access issuance part.

20. A method of controlling access to a data storage array apparatus which comprises a plurality of data storage parts which divide predetermined data and store as data having a redundant configuration, comprising:

an access issuing step of creating and issuing a plurality of second access requests which respectively correspond to said data storage parts based on a predetermined algorithm in response to a first access request;

a monitoring step of monitoring whether processing corresponding to said second access requests thus issued have completed during a predetermined period of time and issuing a result of monitoring; and

a decision step of deciding, based on information included in said result of monitoring thus issued regarding the number of said accesses which have not completed yet, whether to newly issue second access requests at said access issuing step.

21. The method of controlling access to a data storage array apparatus according to claim 20, comprising a historical information holding step of holding historical information, which indicates whether said accesses have been processed normally in said data storage parts, for each one of said data storage parts,

wherein at said decision step, said decision is made considering said historical information as well which is held at said historical information holding step.

23. A program for making a computer execute all or part of said steps of the method of controlling access to a data storage array apparatus according to claim 20.

25. A medium which can be read on a computer and holds a program and/or data for making a computer execute the operations at all or part of said steps of the method of controlling access to a data storage array apparatus according to claim 20.