Triggering, at a host system, a process to reduce declared capacity of a storage device

• US 9,519,427 B2
• Filed: 02/12/2015
• Issued: 12/13/2016
• Est. Priority Date: 09/02/2014
• Status: Active Grant

• Current Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Original Assignee: SanDisk Technologies LLC (Western Digital Corporation)
• Inventors: Samuels, Allen, Kruger, Warren Fritz, Truong, Linh Tien
• Primary Examiner(s): Nguyen, Than
• Application Number:
  US14/621,219
• Publication Number:
  US 20160062664A1
• Time in Patent Office: 670 Days
• Field of Search: 711/103, 711/17, 711/E12.009
• US Class Current: 1/1
• CPC Class Codes: G06F 12/0238 Memory management in non-volatile memory, e.g. resistive RAM or ferroelectric memory
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 12/0253 Garbage collection, i.e. reclamation of unreferenced memory
• CPC Class Codes: G06F 2212/7201 Logical to physical mapping or translation of blocks or pages
• CPC Class Codes: G06F 2212/7204 Capacity control, e.g. partitioning, end-of-life degradation
• CPC Class Codes: G06F 2212/7205 Cleaning, compaction, garbage collection, erase control
• CPC Class Codes: G06F 3/0608 Saving storage space on storage systems
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0631 by allocating resources to storage systems
• CPC Class Codes: G06F 3/0644 Management of space entities, e.g. partitions, extents, pools
• CPC Class Codes: G06F 3/0661 Format or protocol conversion arrangements
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]
• CPC Class Codes: G06F 3/0688 Non-volatile semiconductor memory arrays

Abstract

Systems, methods and/or devices are used to enable triggering, at a host system, a process to reduce declared capacity of a storage device. In one aspect, the method includes, at a host to which a storage device of the storage system is operatively coupled: (1) obtaining one or more metrics of the storage device, the storage device including non-volatile memory, (2) detecting a trigger condition in accordance with the one or more metrics of the storage device, and (3) enabling an amelioration process associated with the detected trigger condition, the amelioration process to reduce declared capacity of the non-volatile memory of the storage device. In some embodiments, the storage device includes one or more flash memory devices.

Claims

1. A method of managing a storage system, the method comprising:

at a host to which a storage device of the storage system is operatively coupled;

obtaining one or more metrics of the storage device, the storage device including non-volatile memory;

detecting a trigger condition in accordance with the one or more metrics of the storage device;

enabling an amelioration process associated with the detected trigger condition, the amelioration process to reduce declared capacity of the non-volatile memory of the storage device, wherein declared capacity is storage capacity available to the host;

prior to detecting the trigger condition, detecting a first wear condition of the non-volatile memory of the storage device, wherein a total storage capacity of the non-volatile memory of the storage device includes declared capacity and over-provisioning; and

in response to detecting the first wear condition, performing a remedial action that reduces over-provisioning of the non-volatile memory of the storage device without reducing declared capacity of the non-volatile memory of the storage device.

2. The method of claim 1, wherein detecting the trigger condition comprises detecting a second wear condition distinct from the first wear condition.

3. The method of claim 1, wherein the host includes a client on behalf of which data is stored in the storage system.

4. The method of claim 1, wherein the host includes a cluster controller of the storage system.

5. The method of claim 1, wherein enabling the amelioration process associated with the detected trigger condition includes scheduling the amelioration process to be performed on the storage device.

6. The method of claim 1, wherein enabling the amelioration process associated with the detected trigger condition includes determining one or more parameters for the amelioration process.

7. The method of claim 6, wherein enabling the amelioration process associated with the detected trigger condition further includes conveying at least a subset of the one or more parameters for the amelioration process to the storage device.

8. The method of claim 1, wherein obtaining one or more metrics of the storage device includes obtaining at least one metric, of the one or more metrics, for each memory portion of a plurality of memory portions of the storage device.

9. The method of claim 1, wherein the one or more metrics of the storage device include one or more status metrics corresponding to the storage device'"'"'s ability to retain data.

10. The method of claim 1, wherein the one or more metrics of the storage device include one or more performance metrics corresponding to performance of the storage device.

11. The method of claim 1, wherein the one or more metrics of the storage device include one or more wear metrics corresponding to wear on the storage device.

12. The method of claim 1, wherein the one or more metrics of the storage device include one or more time metrics.

13. The method of claim 1, wherein the one or more metrics of the storage device include values of the one or more metrics from more than one time.

14. The method of claim 1, further comprising:

after enabling the amelioration process,

re-evaluating the trigger condition in accordance with the one or more metrics of the storage device, and

in accordance with a determination that the trigger condition is no longer valid, aborting the amelioration process to reduce declared capacity of the non-volatile memory of the storage device.

15. The method of claim 1, wherein the amelioration process to reduce declared capacity of the non-volatile memory of the storage device includes a process to reduce utilization of the non-volatile memory of the storage device.

16. The method of claim 1, wherein the storage device comprises one or more flash memory devices.

17. A storage system, comprising:

one or more storage devices; and

a host to which the one or more storage devices are operatively coupled, the host including;

one or more processors; and

host memory storing one or more programs, which when executed by the one or more processors cause the host to perform operations comprising;

obtaining one or more metrics of a storage device of the one or more storage devices, the storage device including non-volatile memory;

detecting a trigger condition in accordance with the one or more metrics of the storage device;

enabling an amelioration process associated with the detected trigger condition, the amelioration process to reduce declared capacity of the non-volatile memory of the storage device, wherein declared capacity is storage capacity available to the host;

prior to detecting the trigger condition, detecting a first wear condition of the non-volatile memory of the storage device, wherein a total storage capacity of the non-volatile memory of the storage device includes declared capacity and over-provisioning; and

in response to detecting the first wear condition, performing a remedial action that reduces over-provisioning of the non-volatile memory of the storage device without reducing declared capacity of the non-volatile memory of the storage device.

18. The storage system of claim 17, wherein detecting the trigger condition comprises detecting a second wear condition distinct from the first wear condition.

19. The storage system of claim 17, wherein the one or more metrics of the storage device include one or more status metrics corresponding to the storage device'"'"'s ability to retain data.

20. The storage system of claim 17, wherein the one or more metrics of the storage device include one or more performance metrics corresponding to performance of the storage device.

21. The storage system of claim 17, wherein the storage device comprises one or more flash memory devices.

22. A non-transitory computer readable storage medium, storing one or more programs configured for execution by one or more processors of a host system, the one or more programs including instructions for:

obtaining one or more metrics of a storage device coupled to the host system, the storage device including non-volatile memory;

detecting a trigger condition in accordance with the one or more metrics of the storage device;

enabling an amelioration process associated with the detected trigger condition, the amelioration process to reduce declared capacity of the non-volatile memory of the storage device, wherein declared capacity is storage capacity available to the host;

prior to detecting the trigger condition, detecting a first wear condition of the non-volatile memory of the storage device, wherein a total storage capacity of the non-volatile memory of the storage device includes declared capacity and over-provisioning; and

in response to detecting the first wear condition, performing a remedial action that reduces over-provisioning of the non-volatile memory of the storage device without reducing declared capacity of the non-volatile memory of the storage device.

23. The non-transitory computer readable storage medium of claim 22, wherein detecting the trigger condition comprises detecting a second wear condition distinct from the first wear condition.

24. The non-transitory computer readable storage medium of claim 22, wherein the one or more metrics of the storage device include one or more status metrics corresponding to the storage device'"'"'s ability to retain data.

25. The non-transitory computer readable storage medium of claim 22, wherein the one or more metrics of the storage device include one or more performance metrics corresponding to performance of the storage device.

26. The non-transitory computer readable storage medium of claim 22, wherein the storage device comprises one or more flash memory devices.