METHOD, APPARATUS AND COMPUTER PROGRAM PRODUCT FOR MANAGING STORAGE SYSTEM

• US 20190332296A1
• Filed: 12/18/2018
• Published: 10/31/2019
• Est. Priority Date: 04/28/2018
• Status: Active Grant

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Inventors: Liu, Yousheng, Xu, Xinlei, Yang, Lifeng, Gao, Jian, Li, Xiongcheng
• Granted Patent: US 11,048,416 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 12/0284 Multiple user address space allocation, e.g. using different base addresses interprocessor communication G06F15/163
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/0611 in relation to response time
• CPC Class Codes: G06F 3/0631 by allocating resources to storage systems
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

A storage system is associated with at least one part of multiple storage devices in a resource pool, a part of a storage space in a storage device being inaccessible to the storage system. Techniques involve: identifying an extent within the part of the storage space in the storage device as a free extent; selecting a group of storage devices each with a free extent from the multiple storage devices in response to determining a virtual address range in the storage system as specified by an access request is inaccessible; mapping the virtual address range to a physical address range of the free extents in the group of storage devices; and allocating a storage space specified by the physical address range to the storage system. Therefore, the expansion of the resource pool can be implemented more conveniently and rapidly, and performance of the storage system can be improved.

Claims

1. A method for managing a storage system, the storage system being associated with at least one part of multiple storage devices in a resource pool, at least one part of a storage space in a storage device among the multiple storage devices being inaccessible to the storage system, the method comprising:

identifying an extent within the at least one part of the storage space in the storage device as a free extent;

selecting a group of storage devices each with a free extent from the multiple storage devices in response to determining a virtual address range in the storage system as specified by an access request is inaccessible;

mapping the virtual address range to a physical address range of the free extents in the group of storage devices; and

allocating a storage space specified by the physical address range to the storage system.

2. The method according to claim 1, wherein the storage system is a storage system based on a Redundant Array of Independent Disks, and wherein selecting a group of storage devices each with a free extent from the multiple storage devices comprises:

determining the number of storage devices in the group on the basis of configuration of the Redundant Array of Independent Disks; and

selecting the group of storage devices on the basis of the number.

3. The method according to claim 1, wherein selecting the group of storage devices on the basis of the number comprises:

determining the free device number of storage devices with free extents from the multiple storage devices; and

in response to determining the free device number meets the number, selecting devices storage devices with free extents as the group of storage devices from the multiple storage.

4. The method according to claim 3, wherein selecting the group of storage devices on the basis of the number further comprises:

moving, to the storage device, data in a first extent in a first storage device other than the storage device in response to determining the free device number does not meet the number;

identifying the first extent as a free extent; and

increasing the free device number.

5. The method according to claim 1, further comprising:

moving, to the storage device, data in a first extent in a first storage device other than the storage device; and

identifying the first extent as a free extent.

6. The method according to claim 1, wherein the storage system is a storage system based on a Redundant Array of Independent Disks, the storage system comprising multiple slices, the method further comprising:

determining an address range of the slice on the basis of a slice allocation table of the storage system in response to receiving a slice access request for a slice among the multiple slices;

determining the virtual address range on the basis of the address range of the slice; and

wherein allocating a storage space specified by the physical address range to the storage system comprises;

selecting a storage space for the slice from the allocated storage space.

7. The method according to claim 6, wherein determining the virtual address range on the basis of the address range of the slice comprises:

determining an address of a bitmap associated with the address range of the slice, a corresponding bit in the bitmap indicating whether data in a corresponding slice among the multiple slices are zero; and

determining the virtual address range on the basis of the address of the bitmap.

8. The method according to claim 7, further comprising:

selecting a bitmap space for storing the bitmap from the allocated storage space; and

in response to determining the user access is a write operation,

writing target data specified by the write operation to the slice; and

setting a bit in the bitmap, which is associated with the slice, to indicate data in the slice are non-zero.

9. The method according to claim 8, wherein the storage device is a new storage device that is inserted into the resource pool during expansion of the resource pool;

and

a physical address of at least one part of a storage space in the new storage device has not been built an address mapping relationship with the storage system.

10. The method according to claim 9, further comprising:

generating a slice access request for each slice among the multiple slices.

11. An apparatus for managing a storage system, comprising:

at least one processor;

a volatile memory; and

a memory coupled to the at least one processor, the memory having instructions stored thereon, the instructions, when executed by the at least one processor, causing the apparatus to perform acts for managing a storage system, the storage system being associated with at least one part of multiple storage devices in a resource pool, at least one part of a storage space in a storage device among the multiple storage devices being inaccessible to the storage system, the acts including;

identifying an extent within the at least one part of the storage space in the storage device as a free extent,

selecting a group of storage devices each with a free extent from the multiple storage devices in response to determining a virtual address range in the storage system as specified by an access request is inaccessible,

mapping the virtual address range to a physical address range of the free extents in the group of storage devices, and

allocating a storage space specified by the physical address range to the storage system.

12. The apparatus according to claim 11, wherein the storage system is a storage system based on a Redundant Array of Independent Disks, and wherein selecting a group of storage devices each with a free extent from the multiple storage devices comprises:

determining the number of storage devices in the group on the basis of configuration of the Redundant Array of Independent Disks; and

selecting the group of storage devices on the basis of the number.

13. The apparatus according to claim 11, wherein selecting the group of storage devices on the basis of the number comprises:

determining the free device number of storage devices with free extents from the multiple storage devices; and

in response to determining the free device number meets the number, selecting devices storage devices with free extents as the group of storage devices from the multiple storage.

14. The apparatus according to claim 13, wherein selecting the group of storage devices on the basis of the number further comprises:

moving, to the storage device, data in a first extent in a first storage device other than the storage device in response to determining the free device number does not meet the number;

identifying the first extent as a free extent; and

increasing the free device number.

15. The apparatus according to claim 11, wherein the acts further comprise:

moving, to the storage device, data in a first extent in a first storage device other than the storage device; and

identifying the first extent as a free extent.

16. The apparatus according to claim 11, wherein the storage system is a storage system based on a Redundant Array of Independent Disks, the storage system comprising multiple slices, the method further comprising:

determining an address range of the slice on the basis of a slice allocation table of the storage system in response to receiving a slice access request for a slice among the multiple slices;

determining the virtual address range on the basis of the address range of the slice; and

wherein allocating a storage space specified by the physical address range to the storage system comprises;

selecting a storage space for the slice from the allocated storage space.

17. The apparatus according to claim 16, wherein determining the virtual address range on the basis of the address range of the slice comprises:

determining an address of a bitmap associated with the address range of the slice, a corresponding bit in the bitmap indicating whether data in a corresponding slice among the multiple slices are zero; and

determining the virtual address range on the basis of the address of the bitmap.

18. The apparatus according to claim 17, wherein the acts further comprise:

selecting a bitmap space for storing the bitmap from the allocated storage space; and

in response to determining the user access is a write operation,

writing target data specified by the write operation to the slice; and

setting a bit in the bitmap, which is associated with the slice, to indicate data in the slice are non-zero.

19. The apparatus according to claim 18, wherein the storage device is a new storage device that is inserted into the resource pool during expansion of the resource pool;

and

a physical address of at least one part of a storage space in the new storage device has not been built an address mapping relationship with the storage system.

20. The apparatus according to claim 19, wherein the acts further comprise:

generating a slice access request for each slice among the multiple slices.

21. A computer program product having a non-transitory computer readable medium which stores a set of instructions for managing a storage system;

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

identifying an extent within the at least one part of the storage space in the storage device as a free extent;

selecting a group of storage devices each with a free extent from the multiple storage devices in response to determining a virtual address range in the storage system as specified by an access request is inaccessible;

mapping the virtual address range to a physical address range of the free extents in the group of storage devices; and

allocating a storage space specified by the physical address range to the storage system.