Operating a raw mirror within a RAID system

Patent metadata

Field	Value
Publication number	US-10649892-B2
Application number	US-201715710809-A
Country	US
Kind code	B2
Filing date	Sep 20, 2017
Priority date	Sep 23, 2016
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

Embodiments of the present disclosure provide a method of managing a redundant array of independent disks (RAID) system and an electronic device. The method includes configuring a plurality of disks in the RAID system as a raw mirror for storing configuration data of the RAID system; storing metadata for the raw mirror in the plurality of disks, the metadata stored in each of the plurality disks including an identifier identifying that the disk belongs to the raw mirror and a sequence number identifying a writing operation for a block storing the metadata in the disk; and controlling reading and writing of the raw mirror based on the metadata.

First claim

We claim:

1. A method of managing a redundant array of independent disks (RAID) system, comprising:
configuring a plurality of disks in the RAID system as a raw mirror for storing configuration data of the RAID system;
storing metadata for the raw mirror in the plurality of disks, the metadata stored in each of the plurality of disks including:
an identifier identifying that the disk belongs to the raw mirror, and
a sequence number identifying a writing operation for a block storing the metadata in the disk;

controlling reading and writing of the raw mirror based on the metadata; and
creating a raw mirror object for the raw mirror to manage the raw mirror, the raw mirror object including at least one of a block size of the raw mirror, an edge array pointing to the raw mirror, a RAID algorithm of the raw mirror, an access switch for the raw mirror, or a capacity of the raw mirror.

2. The method of claim 1 , wherein controlling reading and writing of the raw mirror based on the metadata comprises:
setting the identifiers in the plurality of disks;
increasing the sequence numbers in the plurality of disks; and
writing the configuration data into corresponding blocks of the plurality of disks.

3. The method of claim 1 , wherein controlling reading and writing of the raw mirror based on the metadata comprises:
checking the identifiers in the plurality of disks;
comparing the sequence numbers of corresponding blocks of the plurality of disks; and
reading the configuration data from the corresponding block of the disk with a maximum sequence number.

4. The method of claim 1 , further comprising:
in response to booting of the RAID system, obtaining the sequence numbers of corresponding blocks of the plurality of disks;
comparing the sequence numbers of the corresponding blocks of the plurality of disks; and
storing a maximum sequence number in a cache as the latest sequence numbers for the corresponding blocks.

5. The method of claim 4 , wherein controlling reading and writing of the raw mirror based on the metadata comprises:
obtaining from the cache the latest sequence numbers for the corresponding blocks of the plurality of disks;
increasing the latest sequence numbers;
storing the increased latest sequence numbers into the plurality of disks; and
writing the configuration data into the corresponding blocks of the plurality of disks.

6. The method of claim 1 , further comprising:
creating a RAID group object for the raw mirror to manage the raw mirror.

7. The method of claim 6 , further comprising:
switching an access interface of the raw mirror from the raw mirror object to the RAID group object.

8. The method of claim 6 , further comprising:
performing, with a background service of the RAID system, at least one of driver swapping, data rebuilding, data verification, or data replication on the RAID group object.

9. An electronic device, comprising:
at least one processor, and
at least one memory including computer program instructions, the at least one memory and the computer program instructions configured, with the processor, to cause the device to:
configure a plurality of disks in a redundant array of independent disks (RAID) system as a raw mirror for storing configuration data of the RAID system;
store metadata for the raw mirror in the plurality of disks, the metadata stored in each of the plurality of disks including:
an identifier identifying that the disk belongs to the raw mirror, and
a sequence number identifying a writing operation for a block storing the metadata in the disk;

control reading and writing of the raw mirror based on the metadata; and
create a raw mirror object for the raw mirror to manage the raw mirror, the raw mirror object including at least one of a block size of the raw mirror, an edge array pointing to the raw mirror, a RAID algorithm of the raw mirror, an access switch for the raw mirror, or a capacity of the raw mirror.

10. The device of claim 9 , wherein the at least one memory and the computer program instructions are further configured, with the processor, to cause the device to control reading and writing of the raw mirror by:
setting the identifier in the plurality of disks;
increasing the sequence numbers in the plurality of disks; and
writing the configuration data into corresponding blocks of the plurality of disks.

11. The device of claim 9 , wherein the at least one memory and the computer program instructions are further configured, with the processor, to cause the device to control reading and writing of the raw mirror by:
checking the identifiers in the plurality of disks;
comparing the sequence numbers of corresponding blocks of the plurality of disks; and
reading the configuration data from the corresponding block of the disk with a maximum sequence number.

12. The device of claim 9 , wherein the at least one memory and the computer program instructions are further configured, with the processor, to cause the device to:
in response to booting of the RAID system, obtain the sequence numbers of corresponding blocks of the plurality of disks;
compare the sequence numbers of the corresponding blocks of the plurality of disks; and
store a maximum sequence number in a cache as the latest sequence numbers for the corresponding blocks.

13. The device of claim 12 , wherein the at least one memory and the computer program instructions are further configured, with the processor, to cause the device to control reading and writing of the raw mirror by:
obtaining from the cache the latest sequence numbers for the corresponding blocks of the plurality of disks;
increasing the latest sequence numbers;
storing the increased latest sequence numbers into the plurality of disks; and
writing the configuration data into the corresponding blocks of the plurality of disks.

14. The device of claim 9 , wherein the at least one memory and the computer program instructions are further configured, with the processor, to cause the device to:
create a RAID group object for the raw mirror to manage the raw mirror.

15. The device of claim 14 , wherein the at least one memory and the computer program instructions are further configured, with the processor, to cause the device to:
switch an access interface of the raw mirror from the raw mirror object to the RAID group object.

16. The device of claim 14 , wherein the at least one memory and the computer program instructions are further configured, with the processor, to cause the device to:
perform, with a background service of the RAID system, at least one of driver swapping, data rebuilding, data verification, or data replication on the RAID group object.

17. A computer program product for managing a redundant array of independent disks (RAID) system, the computer program product comprising:
a non-transitory computer readable medium encoded with computer-executable program code for indicating the search result, wherein the code is configured to enable the execution of:
configuring a plurality of disks in the RAID system as a raw mirror for storing configuration data of the RAID system;
storing metadata for the raw mirror in the plurality of disks, the metadata stored in each of the plurality of disks including:
an identifier identifying that the disk belongs to the raw mirror, and
a sequence number identifying a writing operation for a block storing the metadata in the disk;

controlling reading and writing of the raw mirror based on the metadata; and
creating a raw mirror object for the raw mirror to manage the raw mirror

Assignees

• Emc Ip Holding Co Llc

Inventors

• Gao Hongpo
• Sun Ree
• Li Huadong
• Li Wayne
• Dong Jibing
• Gong Shaoqin

Classifications

• G06F3/0643

  Management of files · CPC title

• G06F3/061 Primary

  Improving I/O performance · CPC title

• G06F3/067

  Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS] · CPC title

• G06F3/0689

  Disk arrays, e.g. RAID, JBOD · CPC title

• G06F12/0246 Primary

  in block erasable memory, e.g. flash memory · CPC title