Data management for a data storage device using a last resort zone

• US 9,263,088 B2
• Filed: 06/04/2014
• Issued: 02/16/2016
• Est. Priority Date: 03/21/2014
• Status: Active Grant

• Current Assignee: Western Digital Technologies Incorporated (Western Digital Corporation)
• Original Assignee: Western Digital Technologies Incorporated (Western Digital Corporation)
• Inventors: Fallone, Robert M., Yeo, Teik Ee, Parken, Alec D.
• Primary Examiner(s): ALUNKAL, THOMAS D
• Application Number:
  US14/295,497
• Publication Number:
  US 20150269964A1
• Time in Patent Office: 622 Days
• Field of Search: 360/48, 360/31, 360/55
• US Class Current: 1/1
• CPC Class Codes: G11B 19/041 Detection or prevention of read or write errors
• CPC Class Codes: G11B 19/046 Detection or prevention or problems due to temperature
• CPC Class Codes: G11B 20/1217 on discs
• CPC Class Codes: G11B 20/1889 with discs
• CPC Class Codes: G11B 2020/1242 the area forming one or more zones, wherein each zone is shaped like an annulus or a circular sector
• CPC Class Codes: G11B 2020/1869 Preventing ageing phenomena from causing data loss, e.g. by monitoring the age of record carriers or by recognising wear, and by copying information elsewhere when a record carrier becomes unreliable

Abstract

A data storage device (DSD) includes a non-volatile memory (NVM) media for storing data. A last resort zone of the NVM media is associated with a higher risk of data loss or data corruption than other portions of the NVM media and is reserved as unavailable for storing data. It is determined whether a current data storage capacity and/or an environmental condition for the NVM media has reached a threshold. The last resort zone is set as available for storing data if it is determined that the threshold has been reached and data is written in the last resort zone.

Claims

1. A data storage device (DSD) comprising:

non-volatile memory (NVM) media including a last resort zone associated with a higher risk of data loss or data corruption than other portions of the NVM media; and

a controller configured to;

assign the last resort zone to a portion of the NVM media when more than a predetermined number of defects or errors are identified in the portion of the NVM;

reserve the last resort zone as unavailable for storing data;

determine whether a current data storage capacity and/or an environmental condition for the NVM media has reached a threshold;

set the last resort zone as available for storing data if it is determined that the threshold has been reached; and

write data in the last resort zone.

2. The DSD of claim 1, wherein the NVM media includes a magnetic media.

3. The DSD of claim 1, wherein the NVM media includes a solid state memory.

4. The DSD of claim 1, wherein the controller is further configured to manage access of the NVM media using an address translation table.

5. The DSD of claim 1, wherein the controller is further configured to set the last resort zone as available for storing data by allocating logical addresses to the last resort zone.

6. The DSD of claim 1, wherein the controller is further configured to reserve the last resort zone by allocating logical addresses to portions of the NVM media outside of the last resort zone without allocating logical addresses to the last resort zone.

7. The DSD of claim 1, wherein the NVM media includes a disk and the last resort zone is located on the disk.

8. The DSD of claim 7, wherein the last resort zone is located in an outer diameter portion of the disk.

9. The DSD of claim 8, further comprising a head for reading and writing data on the disk, and wherein the last resort zone is more susceptible to contact by the head than other portions of the disk.

10. The DSD of claim 7, wherein the last resort zone is located in an inner diameter portion of the disk.

11. The DSD of claim 7, wherein the controller is further configured to adjust write settings for writing data in the last resort zone.

12. The DSD of claim 11, wherein each track on the disk includes a plurality of sectors, and wherein the controller is further configured to:

attempt to write data in a particular sector of the plurality of sectors for a predetermined number of write retries; and

adjust write settings for writing data in the last resort zone by reducing the predetermined number of write retries when attempting to write data in the last resort zone.

13. The DSD of claim 11, wherein the controller is further configured to adjust write settings for writing data in the last resort zone by reading data written in the last resort zone to verify the data written in the last resort zone.

14. The DSD of claim 11, wherein the controller is further configured to adjust write settings for writing data in the last resort zone by changing a track density for writing data in the last resort zone.

15. The DSD of claim 11, wherein the controller is further configured to adjust write settings for writing data in the last resort zone based on whether there is a duplicate copy of the data written in the NVM media outside of the last resort zone.

16. The DSD of claim 1, wherein the data written in the last resort zone includes data accessed with a reading frequency and/or a writing frequency outside of a threshold frequency.

17. The DSD of claim 1, wherein the environmental condition includes at least one of an operating temperature and a vibration condition of the DSD.

18. A method for operating a data storage device (DSD) including non-volatile memory (NVM) media, the method comprising:

assigning a last resort zone to a portion of the NVM media when more than a predetermined number of defects or errors are identified in the portion of the NVM, wherein the last resort zone is associated with a higher risk of data loss or data corruption than other portions of the NVM media;

reserving the last resort zone of the NVM media as unavailable for storing data;

determining whether a current data storage capacity and/or an environmental condition for the NVM media has reached a threshold;

setting the last resort zone as available for storing data if it is determined that the threshold has been reached; and

writing data in the last resort zone.

19. The method of claim 18, wherein the NVM media includes a magnetic media.

20. The method of claim 18, wherein the NVM media includes a solid state memory.

21. The method of claim 18, further comprising managing access of the NVM media using an address translation table.

22. The method of claim 18, further comprising setting the last resort zone as available for storing data by allocating logical addresses to the last resort zone.

23. The method of claim 18, further comprising reserving the last resort zone by allocating logical addresses to portions of the NVM media outside of the last resort zone without allocating logical addresses to the last resort zone.

24. The method of claim 18, wherein the NVM media includes a disk and the last resort zone is located on the disk.

25. The method of claim 24, wherein the last resort zone is located in an outer diameter portion of the disk.

26. The method of claim 25, wherein the last resort zone is more susceptible to contact by a head of the DSD than other portions of the disk.

27. The method of claim 24, wherein the last resort zone is located in an inner diameter portion of the disk.

28. The method of claim 24, further comprising adjusting write settings for writing data in the last resort zone.

29. The method of claim 28, wherein the disk includes a plurality of sectors for storing data, and wherein the method further comprises:

attempting to write data in a particular sector of the plurality of sectors for a predetermined number of write retries; and

adjusting write settings for writing data in the last resort zone by reducing the predetermined number of write retries when attempting to write data in the last resort zone.

30. The method of claim 28, further comprising adjusting write settings for writing data in the last resort zone by reading data written in the last resort zone to verify the data written in the last resort zone.

31. The method of claim 28, further comprising adjusting write settings for writing data in the last resort zone by changing a track density for writing data in the last resort zone.

32. The method of claim 28, further comprising adjusting write settings for writing data in the last resort zone based on whether there is a duplicate copy of the data written in the NVM media outside of the last resort zone.

33. The method of claim 18, wherein the data written in the last resort zone includes data accessed with a reading frequency and/or a writing frequency outside of a threshold frequency.

34. The method of claim 18, wherein the environmental condition includes at least one of an operating temperature and a vibration condition of the DSD.