Storage system management method, electronic device, storage system and computer program product

Patent metadata

Field	Value
Publication number	US-10831604-B2
Application number	US-201816179428-A
Country	US
Kind code	B2
Filing date	Nov 2, 2018
Priority date	Jan 18, 2018
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

Embodiments of the present disclosure relate to a method for managing a storage system, an electronic device, a storage system and a computer program product. The method includes: expanding a second number of existing disks with a first number of expanded disks to rebuild a redundant array of independent disks (RAID) having a predetermined extent width, the RAID being built based on the existing disks, and the predetermined extent width indicating a number of disk extents from different disks that form an RAID extent. The method further includes: determining a third number of RAID extents contained in the rebuilt RAID. The method further includes: determining a count of data movements to be performed between the expanding disks and the existing disks during the rebuilding based on the first number, the second number, the third number and the predetermined extent width. With this method, time for estimating count of data movements may be reduced.

First claim

What is claimed is:

1. A method for managing a storage system, comprising:
expanding, with a first number of expanding disks, a second number of existing disks to rebuild a redundant array of independent disks (RAID) having a predetermined extent width, the RAID being built based on the existing disks, and the predetermined extent width indicating a number of disk extents from different disks that form an RAID extent;
determining a third number of RAID extents contained in the rebuilt RAID; and
determining, based on the first number, the second number, the third number and the predetermined extent width, a count of data movements to be performed between the expanding disks and the existing disks during the rebuilding;
wherein determining the count comprises:
comparing the first number with the predetermined extent width; and
in response to the first number being less than the predetermined extent width:
determining, based on the first number, the second number, the third number and the predetermined extent width, a first count of data movements to be performed from the existing disks to the expanding disks during the rebuilding.

2. The method according to claim 1 , wherein determining the first count comprises:
determining, based on the third number and the predetermined extent width, a fourth number of disk extents for the rebuilding in the existing disks and the expanding disks;
determining a ratio of the first number of the expanding disks to a total number of the expanding disks and the existing disks, the total number being a sum of the first number and the second number; and
determining, based on the fourth number and the ratio, a number of disk extents for the rebuilding in the expanding disks as the first count.

3. The method according to claim 1 further comprising in response to the first number being greater than or equal to the predetermined extent width:
determining, based on the first number, the second number, the third number and the predetermined extent width, the first count of data movements to be performed from the existing disks to the expanding disks and a second count of data movements to be performed from the expanding disks to the existing disks during the rebuilding; and
determining the count based on the first count and the second count.

4. The method according to claim 3 , wherein determining the first count and the second count comprises:
determining, based on the first number, the second number, the third number and the predetermined extent width, a predicted count of co-occurrences for disk extents of the existing disks with disk extents of the expanding disks in same RAID extents of the rebuilt RAID; and
determining the first count and the second count, so that a count of co-occurrences for disk extents of the existing disks with disk extents of the expanding disks in same RAID extents of the rebuilt RAID reaches the predicted count after the first count of data movements from the existing disks to the expanding disks and the second count of data movements from the expanding disks to the existing disks are performed.

5. The method according to claim 4 , wherein determining the predicted count comprises:
determining, based on the third number and the predetermined extent width, a fifth count of co-occurrences for disk extents of the existing disks and the expanding disks with each other in a same RAID extent of the rebuilt RAID; and
determining the predicted count based on the fifth count, the first number and the second number.

6. The method according to claim 1 , further comprising:
determining time required by the rebuilding based on the count.

7. The method of claim 1 , further comprising defining a pool of storage disks for storing data in accordance with the RAID utilizing a mapped RAID arrangement, wherein the first number of expanding disks and the second number of existing disks are part of the pool of storage disks.

8. An electronic device, comprising:
at least one processor; and
at least one memory containing computer program instructions, the at least one memory and the computer program instructions being configured to, together with the at least one processor, cause the electronic device to perform acts including:
expanding, with a first number of expanding disks, a second number of existing disks to rebuild a redundant array of independent disks (RAID) having a predetermined extent width, the RAID being built based on the existing disks, and the predetermined extent width indicating a number of disk extents from different disks that form an RAID extent;
determining a third number of RAID extents contained in the rebuilt RAID; and
determining, based on the first number, the second number, the third number and the predetermined extent width, a count of data movements to be performed between the expanding disks and the existing disks during the rebuilding
wherein the acts further comprise:
comparing the first number with the predetermined extent width; and
in response to the first number being less than the predetermined extent width:
determining, based on the first number, the second number, the third number and the predetermined extent width, a first count of data movements to be performed from the existing disks to the expanding disks during the rebuilding.

9. The electronic device according to claim 8 wherein the acts further comprise:
determining, based on the third number and the predetermined extent width, a fourth number of disk extents for the rebuilding in the existing disks and the expanding disks;
determining a ratio of the first number of the expanding disks to a total number of the expanding disks and the existing disks, the total number being a sum of the first number and the second number; and
determining, based on the fourth number and the ratio, a number of disk extents for the rebuilding in the expanding disks as the first count.

10. The electronic device according to claim 8 , wherein the acts further comprise:
in response to the first number being greater than equal to the predetermined extent width,
determining, based on the first number, the second number, the third number and the predetermined extent width, the first count of data movements to be performed from the existing disks to the expanding disks and a second count of data movements to be performed from the expanding disks to the existing disks during the rebuilding; and
determining the count based on the first count and the second count.

11. The electronic device according to claim 10 , wherein the acts further comprise:
determining, based on the first number, the second number, the third number and the predetermined extent width, a predicted count of co-occurrences for disk extents of the existing disks with disk extents of the expanding disks in same RAID extents of the rebuilt RAID; and
determining the first count and the second count, so that a count of co-occurrences for disk extents of the existing disks with disk extents of the expanding disks in same RAID extents of the rebuilt RAID reaches the predicted count after the first count of data movements from the existing disks to the expanding disks and the second count of data movements from the expanding disks to the existing disks are performed.

12. The electronic device according to claim 11 , wherein the acts further comprise:
determining, based on the third number and the predetermined extent width, a fifth count of co-occurrences for disk extents of the existing disks and the expanding disks with each other in a same RAID extent of the rebuilt RAID; and
determining the predicted count based on the fifth count, the first number and the second nu

Assignees

• Dell Products Lp

Inventors

• Han Geng
• Gao Jian
• Dong Jibing
• Gao Hongpo
• Zhuo Baote

Classifications

• G06F11/1076 Primary

  Parity data used in redundant arrays of independent storages, e.g. in RAID systems · CPC title

• G06F3/0619

  in relation to data integrity, e.g. data losses, bit errors · CPC title

• G06F3/061

  Improving I/O performance · CPC title

• G06F3/0689

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

• G06F2201/88

  Monitoring involving counting · CPC title