Array-type disk apparatus preventing data lost and providing improved failure tolerance

• US 7,913,039 B2
• Filed: 06/04/2010
• Issued: 03/22/2011
• Est. Priority Date: 09/26/2003
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Yamamoto, Akira, Fukuoka, Mikio, Okamoto, Takeki, Takamoto, Kenichi, Matsunami, Naoto, Nakano, Toshio, Yagisawa, Ikuya
• Primary Examiner(s): Ellis; Kevin L
• Assistant Examiner(s): Bradley; Matthew
• Application Number:
  US12/793,988
• Publication Number:
  US 20100241898A1
• Time in Patent Office: 291 Days
• Field of Search: 711/114
• US Class Current: 711/114
• CPC Class Codes: G06F 11/008 Reliability or availability analysis
• CPC Class Codes: G06F 11/1662 the resynchronized component or unit being a persistent storage device re-synchronization of failed mirror storage G06F11/2082; rebuild or reconstruction of parity RAID storage G06F11/1008
• CPC Class Codes: G06F 11/2069 Management of state, configuration or failover
• CPC Class Codes: G06F 11/2089 Redundant storage control functionality
• CPC Class Codes: G06F 11/2094 Redundant storage or storage space G06F11/2056 takes precedence
• CPC Class Codes: G06F 11/2097 maintaining the standby controller/processing unit updated initialisation or re-synchronisation thereof G06F11/1658 and subgroups
• CPC Class Codes: G06F 2201/81 Threshold

Abstract

A storage system includes a plurality of disk apparatuses configuring a plurality of RAID groups, a spare disk apparatus, and a controller. The controller is adapted to copy data stored in a disk apparatus, whose error count exceeds a first threshold, to the spare disk apparatus. If an error count of a disk apparatus included in a RAID group exceeds a second threshold which is lower than the first threshold, the controller is adapted to check error counts of other disk apparatuses included in the same RAID group. If any of the error counts of the other disk apparatuses included in the same RAID group exceeds the second threshold, the controller is adapted to change the first value of the first disk apparatus and the other disk apparatuses included in the same RAID group.

Claims

1. A storage system comprising:

a plurality of disk apparatuses configuring a plurality of RAID groups including a first RAID group;

a spare disk apparatus; and

a controller is adapted to copy data stored in a disk apparatus, whose error count exceeds a first threshold, to said spare disk apparatus;

wherein, if an error count of a first disk apparatus included in said first RAID group exceeds a second threshold which is lower than said first threshold, said controller is adapted to check error counts of other disk apparatuses included in said first RAID group, and

wherein if any of said error counts of said other disk apparatuses included in said first RAID group exceeds said second threshold, said controller is adapted to change a value of said first threshold with respect to said first disk apparatus and said other disk apparatuses included in said first RAID group.

2. A storage system according to claim 1:

wherein if any of said error counts of said other disk apparatuses included in said first RAID group exceeds said second threshold, said controller is adapted to decrease said value of said first threshold with respect to said first disk apparatus and said other disk apparatuses included in said first RAID group.

3. A storage system according to claim 2:

wherein said decreased value of said first threshold is an intermediate value of said previous first threshold and said second threshold.

4. A storage system according to claim 1:

wherein said controller includes a memory storing error management information which manages an error occurrence count of said disk apparatuses including said first disk apparatus,

wherein said controller monitors the error occurrence count of said disk apparatuses, and

wherein when an error has occurred in one of said disk apparatuses, said controller adds to the error occurrence count of said one disk apparatus in the error management information.

5. A storage system according to claim 4:

wherein said first threshold of each of the plurality of disk drives is stored in said error management information, and

wherein said controller discovers said first disk apparatus by referring to said error management information.

6. A storage system according to claim 4:

wherein said error management information stores said second threshold of each of the plurality of disk drives, and

wherein said controller discovers said first disk apparatus by referring to said error management information.

7. A storage system according to claim 1, comprising:

wherein said controller is adapted to make a status of said first disk apparatus, whose error count exceeds a first threshold, a blocked status after copying data stored in said first disk apparatus to said spare disk apparatus.

8. A storage system according to claim 1:

wherein exceeding said first threshold, by said first disk apparatus, indicates that said first disk apparatus has a high possibility of failure occurrence.

9. A method in a storage system having a plurality of information processing devices configuring a plurality of information processing device groups including a first information processing device group and a spare information processing device, the method comprising the steps of:

when an error count of an information processing device exceeds a first threshold, copying data from said information processing device to said spare information processing device;

if an error count of a first information processing device included in said first information processing device group exceeds a second threshold which is lower than said first threshold, checking error counts of other information processing devices included in said first information processing device group, and

if any of said error counts of said other information processing devices included in said first information processing device group exceeds said second threshold, changing a value said first threshold with respect to said first information processing device and said other information processing devices included in said first information processing device group.

10. A method according to claim 9, wherein the step of changing the first value further comprises the step of:

decreasing said value of said first threshold with respect to said first information processing device and said other information processing devices included in said first information processing device group.

11. A method according to claim 10:

wherein said decreased value of said first threshold is an intermediate value of said previous first threshold and said second threshold.

12. A method according to claim 9, further comprising the steps of:

storing error management information which manages an error occurrence count of said information processing devices including said first information processing device;

monitoring the error occurrence count of said information processing devices; and

when an error has occurred in one of said information processing devices, adding to the error occurrence count of said one information processing device in the error management information.

13. A method according to claim 12, further comprising the steps of:

storing said first threshold of each of the plurality of disk drives in said error management information; and

discovering said first information processing device by referring to said error management information.

14. A method according to claim 12, further comprising the steps of:

storing said second threshold of each of the plurality of disk drives in said error management information; and

discovering said first information processing device by referring to said error management information.

15. A method according to claim 9, further comprising the step of:

making a status of said first information processing device, whose error count exceeds a first threshold, a blocked status after copying data stored in said first information processing device to said spare information processing device.

16. A method according to claim 9:

wherein exceeding said first threshold, by said first information processing device, indicates that said first information processing device has a high possibility of failure occurrence.