Dynamic rebuild capability in redundant array of independent disks (RAID) arrays using compressing drives

1. A computer-implemented method for dynamic rebuild capability in redundant array of independent disks (RAID) arrays using compressing drives, comprising:

providing an array including a physical rebuild area for the multiple drives of the array;

dynamically adjusting a number of allocated rebuild zones available within the rebuild area, wherein each allocated rebuild zone has capacity to store a drive rebuild based on a current physical usage of the multiple drives of the array; and

monitoring the current physical usage of the multiple drives of the array including an amount of compression being used, wherein the current physical usage includes data storage and fault tolerance and is based on a highest individual drive usage of the multiple drives.

2. The method as claimed in claim 1 , wherein, in the event of a drive failure and a rebuild zone being in use, the current physical usage includes the rebuild zone use.

3. The method as claimed in claim 1 , wherein dynamically adjusting a number of allocated rebuild zones includes:

decreasing the number of allocated rebuild zones whilst maintaining a guaranteed minimum number of zones in response to an increase in the current physical usage; and

increasing the number of allocated rebuild zones within a defined maximum number of zones in response to a decrease in the current physical usage.

4. The method as claimed in claim 3 , wherein providing an array includes defining the physical rebuild area with a defined maximum number of allocated rebuild zones including a configured guaranteed number of rebuild zones and an initial number of dynamic rebuild zones based on an initial drive physical usage.

5. The method as claimed in claim 4 , wherein decreasing and increasing the number of allocated rebuild zones varies the number of dynamic rebuild zones.

6. The method as claimed in claim 3 , wherein, in the event of increased drive physical usage such that the guaranteed minimum number of zones is not sufficient, providing a remedial action.

7. The method as claimed in claim 6 , wherein the remedial action is one or more of the group of: blocking writes, compromising a rebuild, reconfiguring the number of guaranteed rebuild zones, copyback of the rebuild data to a replacement drive to free the rebuild area, data migration, and data deletion.

8. The method as claimed in claim 3 , wherein a size of the physical rebuild area is the number of guaranteed rebuild zones multiplied by a physical size of a drive.

9. The method as claimed in claim 1 , wherein the physical rebuild area is a distributed physical rebuild area across multiple drives of the array, and

wherein an allocated rebuild zone is provided across active drives of the rebuild area.

10. The method as claimed in claim 1 , wherein the physical rebuild area is one or more spare drives in the array, and

wherein an allocated rebuild zone is a provided in the one or more spare drives of the physical rebuild area.

11. A system for dynamic rebuild capability in redundant array of independent disks (RAID) arrays using compressing drives, comprising:

an array including a physical rebuild area for the multiple drives of the array; and

a processor and a memory configured to provide computer program instructions to the processor to execute the function of:

a dynamic rebuild zone component for dynamically adjusting a number of allocated rebuild zones available within the rebuild area, wherein each allocated rebuild zone has capacity to store a drive rebuild based on a current physical usage of the multiple drives of the array; and

a data usage monitoring component for monitoring the current physical usage including an amount of compression being used, wherein the current physical usage includes data storage and fault tolerance and is based on a highest individual drive usage of the multiple drives.

12. The system as claimed in claim 11 , including a drive failure component for, in the event of a drive failure and a rebuild zone being in use, providing the current physical usage includes the rebuild zone use.

13. The system as claimed in claim 11 , wherein the dynamic rebuild zone component includes:

a zone decreasing component for decreasing the number of allocated rebuild zones whilst maintaining a guaranteed minimum number of zones in response to an increase in the current physical usage; and

a zone increasing component for increasing the number of allocated rebuild zones within a defined maximum number of zones in response to a decrease in the current physical usage.

14. The system as claimed in claim 13 , including a rebuild area configuring component for defining the physical rebuild area with a defined maximum number of allocated rebuild zones including a configured guaranteed number of rebuild zones and an initial number of dynamic rebuild zones based on an initial drive physical usage.

15. The system as claimed in claim 13 , wherein, the zone decreasing component includes a remedial component for providing a remedial action in the event of increased drive physical usage such that the guaranteed minimum number of zones is not sufficient.

16. The system as claimed in claim 11 , wherein the physical rebuild area is a distributed physical rebuild area across multiple drives of the array, and

wherein an allocated rebuild zone is provided across active drives of the rebuild area.

17. The system as claimed in claim 11 , wherein the physical rebuild area is one or more spare drives in the array, and

wherein an allocated rebuild zone is a provided in the one or more spare drives of the physical rebuild area.

18. A computer program product for dynamic rebuild capability in redundant array of independent disks (RAID) arrays using compressing drives, the computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions executable by a processor to cause the processor to:

provide an array including a physical rebuild area for the multiple drives of the array;

dynamically adjust a number of allocated rebuild zones available within the rebuild area, wherein each allocated rebuild zone has capacity to store a drive rebuild based on a current physical usage of the multiple drives of the array; and

monitor the current physical usage of the multiple drives of the array including an amount of compression being used, wherein the current physical usage includes data storage and fault tolerance and is based on a highest individual drive usage of the multiple drives.