METHOD AND DEVICE FOR REBUILDING DATA IN STORAGE ARRAY GROUP

• US 20200133503A1
• Filed: 10/17/2019
• Published: 04/30/2020
• Est. Priority Date: 10/29/2018
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Inventors: Sun, Lei, Gao, Jian, Gao, Hongpo
• Granted Patent: US 11,442,651 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 11/1088 Reconstruction on already foreseen single or plurality of spare disks
• CPC Class Codes: G06F 11/1092 Rebuilding, e.g. when physically replacing a failing disk
• CPC Class Codes: G06F 11/2094 Redundant storage or storage space G06F11/2056 takes precedence
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/0659 Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/0683 Plurality of storage devices
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

Techniques rebuild data in a storage array group. Such techniques involve: in response to determining that a first storage device of a plurality of storage devices comprised in the storage array group is in a non-working state, generating a write record of the first storage device, the write record indicating whether a write operation occurs for each of a plurality of storage areas in the first storage device during the non-working state; in response to determining that the first storage device returns from the non-working state to a working state, determining, based on the write record, whether a target storage area in need of execution of data rebuilding is present in the first storage device; and controlling, based on the determining, the data rebuilding to be executed on the target storage area.

Claims

1. A method for rebuilding data in a storage array group, the method comprising:

in response to determining that a first storage device of a plurality of storage devices comprised in the storage array group is in a non-working state, generating a write record of the storage device, the write record indicating whether a write operation occurs for each of a plurality of storage areas in the first storage device during the non-working state;

in response to determining that the first storage device returns from the non-working state to a working state, determining, based on the write record, whether a target storage area in need of execution of data rebuilding is present in the first storage device; and

controlling, based on the determining, the data rebuilding to be executed on the target storage area.

2. The method of claim 1, wherein the write record comprises a plurality of bits, each bit of the plurality of bits corresponding to a respective storage area of the plurality of storage areas and indicating whether the write operation occurs for the respective storage area.

3. The method of claim 1, wherein generating the write record comprises:

initializing the write record;

in response to determining that the write operation occurs for the first storage device during the non-working state, calculating an address range of the write operation;

determining, based on the calculated address range, the storage area for which the write operation occurs; and

setting the write record to indicate the determined storage area.

4. The method of claim 1, wherein

determining whether the target storage area is present based on the write record comprises:

in response to the write record indicating that no write operation occurs for the storage area of the first storage device during the non-working state, determining absence of the target storage area; and

controlling the data rebuilding based on the determining comprises;

generating an indication of completion of the data rebuilding without executing the data rebuilding on the first storage device.

5. The method of claim 1, wherein

determining whether the target storage area is present based on the write record comprises:

in response to the write record indicating that the write operation occurs for the storage area of the first storage device during the non-working state;

setting the storage area as the target storage area; and

determining presence of the target storage area; and

controlling the data rebuilding based on the determining comprises;

determining, for each storage area in the target storage area, an address range of the storage area on which the write operation is to be performed;

executing the data rebuilding for the address range; and

generating an indication of completion of the data rebuilding.

6. The method of claim 1, wherein the data rebuilding is executed in units of chunks in the target storage area.

7. The method of claim 1, further comprising:

in response to determining that the first storage device maintains in the non-working state for more than a predetermined time period, executing the data rebuilding in a backup storage device associated with the first storage device by using all data for the first storage device.

8. The method of claim 1, further comprising:

storing, in a backup area, data to be written into the first storage device, the backup area comprised in any storage device of the plurality of storage devices other than the first storage device.

9. The method of claim 1, wherein the write record is comprised in metadata recording a configuration of the storage array group.

10. The method of claim 9, wherein the write record is a bitmap corresponding to the first storage device.

11. An electronic device, comprising:

a processor; and

a memory coupled to the processor, the memory having instructions stored therein, the instructions, when executed by the processor, causing the electronic device to perform acts comprising;

in response to determining that a first storage device of a plurality of storage devices comprised in the storage array group is in a non-working state, generating a write record of the storage device, the write record indicating whether a write operation occurs for each of a plurality of storage areas in the first storage device during the non-working state;

in response to determining that the first storage device returns from the non-working state to a working state, determining, based on the write record, whether a target storage area in need of execution of data rebuilding is present in the first storage device; and

in response to determining whether the target storage area is present, controlling the data rebuilding to be executed on the target storage area.

12. The device of claim 11, wherein the write record comprises a plurality of bits, each bit of the plurality of bits corresponding to a respective storage area of the plurality of storage areas and indicating whether the write operation occurs for the respective storage area.

13. The device of claim 11, wherein generating the write record comprises:

initializing the write record;

in response to determining that the write operation occurs for the first storage device during the non-working state, calculating an address range of the write operation;

determining, based on the calculated address range, the storage area for which the write operation occurs; and

setting the write record to indicate the determined storage area.

14. The device of claim 11, wherein

determining whether the target storage area is present based on the write record comprises:

in response to the write record indicating that no write operation occurs for the storage area of the first storage device during the non-working state, determining absence of the target storage area; and

controlling the data rebuilding based on the determining comprises;

generating an indication of completion of the data rebuilding without executing the data rebuilding on the first storage device.

15. The device of claim 11, wherein:

determining whether the target storage area is present based on the write record comprises;

in response to the write record indicating that the write operation occurs for the storage area of the first storage device during the non-working state;

setting the storage area as the target storage area; and

determining presence of the target storage area; and

controlling the data rebuilding based on the determining comprises;

determining, for each storage area in the target storage area, an address range of the storage area on which the write operation is to be performed;

executing the data rebuilding for the address range; and

generating an indication of completion of the data rebuilding.

16. The device of claim 11, wherein the data rebuilding is executed in units of chunks in the target storage area.

17. The device of claim 11, wherein the acts further comprise:

in response to determining that the first storage device maintains in the non-working state for more than a predetermined time period, executing the data rebuilding in a backup storage device associated with the first storage device by using all data for the first storage device.

18. The device of claim 11, wherein the acts further comprise:

storing, in a backup area, data to be written into the first storage device, the backup area comprised in any storage device of the plurality of storage devices other than the first storage device.

19. The device of claim 11, wherein the write record is comprised in metadata recording a configuration of the storage array group.

20. The device of claim 19, wherein the write record is a bitmap corresponding to the first storage device.

21. A computer program product having a non-transitory computer readable medium which stores a set of instructions to rebuild data in a storage array group;

the set of instructions, when carried out by computerized circuitry, causing the computerized circuitry to perform a method of;

in response to determining that a first storage device of a plurality of storage devices comprised in the storage array group is in a non-working state, generating a write record of the storage device, the write record indicating whether a write operation occurs for each of a plurality of storage areas in the first storage device during the non-working state;

in response to determining that the first storage device returns from the non-working state to a working state, determining, based on the write record, whether a target storage area in need of execution of data rebuilding is present in the first storage device; and

controlling, based on the determining, the data rebuilding to be executed on the target storage area.