Hybrid hard disk drive control method and recording medium and apparatus suitable therefor

Abstract

A method of controlling a hybrid HDD to permanently deactivate a non-volatile cache support mode by determining whether a limit in the use of a non-volatile cache is passed, and a recording medium and apparatus suitable for the control method. The control method of a hybrid hard disk drive having a hard disk and a non-volatile cache includes determining whether an erasure number of the non-volatile cache exceeds a usage limit based on the erasure number of the non-volatile cache, and permanently deactivating a non-volatile cache support mode when the erasure number of the non-volatile cache is determined to exceed the usage limit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects and advantages of the present general inventive concept will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a graph illustrating a relationship between an error of a flash memory and an erasure number limit;

FIG. 2 is a flowchart illustrating a method of controlling a hybrid HDD according to an embodiment of the present general inventive concept;

FIG. 3 is a flowchart illustrating a method of controlling a hybrid HDD according to another embodiment of the present general inventive concept;

FIG. 4 is a plan view illustrating the configuration of a hybrid HDD according to an embodiment of the present general inventive concept; and

FIG. 5 is a block diagram illustrating the configuration of a circuit to control the hybrid HDD of FIG. 4.

Claims

1. A method of controlling a hybrid hard disk drive comprising a hard disk and a non-volatile cache, the method comprising: determining whether an erasure number of the non-volatile cache exceeds a usage limit based on the erasure number of the non-volatile cache; andpermanently deactivating a non-volatile cache support mode when the erasure number of the non-volatile cache is determined to exceed the usage limit.

2. The method of claim 1, wherein the determining of the usage limit comprises: determining the erasure number of the non-volatile cache by counting the number of erasing operations performed by the non-volatile cache; anddetermining that the erasure number of the non-volatile cache exceeds the usage limit when the erasure number is greater than a predetermined erasure limit number.

3. The method of claim 2, wherein the erasure number is recorded in a spare area of the non-volatile cache or a block assigned to maintenance data.

4. The method of claim 1, wherein the determining of the usage limit comprises: determining the erasure number for each of blocks of the non-volatile cache by counting the number of erasing operations performed by the non-volatile cache;determining a no-write block number by counting the number of block, for which the erasure number is greater than a predetermined erasure limit number; anddetermining that the erasure number of the non-volatile cache exceeds a usage limit when the no-write block number is greater than a predetermined threshold value.

5. The method of claim 4, wherein the erasure number is recorded in a spare area of the non-volatile cache or a block assigned to maintenance data.

6. The method of claim 4, wherein the determining of the usage limit further comprises: detecting a defective block number of the non-volatile cache by detecting the number of defective blocks in the non-volatile cache; anddetermining that the erasure number of the non-volatile cache exceeds a usage limit when the defective block number is not less than a predetermined threshold value.

7. The method of claim 1, wherein the determining of the usage limit comprises: detecting a defective block number of the non-volatile cache by detecting the number of defective blocks in the non-volatile cache; anddetermining that the erasure number of the non-volatile cache exceeds a usage limit when the defective block number is not less than a predetermined threshold value.

8. The method of claim 1, wherein the erasure number is recorded in a spare area of the non-volatile cache or a block assigned to maintenance data.

9. The method of claim 1, further comprising: notifying a host device of a non-volatile cache support mode being deactivated, wherein the host device is notified when a recording in the non-volatile cache is no longer effective, so that the host device no longer uses the non-volatile cache.

10. A computer readable recording medium containing a program executing a method of controlling a hybrid hard disk drive having a hard disk and a non-volatile cache, wherein the method comprises: determining whether the erasure number of the non-volatile cache exceeds a usage limit based on the number of erasing operations of the non-volatile cache; andpermanently deactivating a non-volatile cache support mode when the erasure number of the non-volatile cache is determined to exceed the usage limit.

11. The computer readable recording medium of claim 10, wherein the determining of the usage limit further comprises: determining the erasure number of the non-volatile cache by counting the number of erasing operations performed by the non-volatile cache; anddetermining that the erasure number of the non-volatile cache exceeds the usage limit when the erasure number is greater than a predetermined erasure limit number.

12. The computer readable recording medium of claim 10, wherein the determining of the usage limit further comprises: determining the erasure number for each of blocks of the non-volatile cache by counting the number of erasing operations performed by the non-volatile cache;counting a no-write block number by detecting the number of blocks, for which the erasure number is greater than a predetermined erasure limit number; anddetermining that the erasure number of the non-volatile cache exceeds a usage limit when the no-write block number is greater than a predetermined threshold value.

13. The computer readable recording medium of claim 10, wherein the determining of the usage limit further comprises: detecting a defective block number of the non-volatile cache by detecting the number of defective blocks in the non-volatile cache; anddetermining that the erasure number of the non-volatile cache exceeds a usage limit when the defective block number is not less than a predetermined threshold value.

14. The computer readable recording medium of claim 10, wherein the determining of the usage limit further comprises: detecting a defective block number of the non-volatile cache by detecting the number of defective blocks in the non-volatile cache; anddetermining that the erasure number of the non-volatile cache exceeds a usage limit when the defective block number is not less than a predetermined threshold value.

15. The computer readable recording medium of claim 10, wherein the method of controlling a hybrid hard disk drive having a hard disk and a non-volatile cache further comprises: an operation of notifying a host device of a non-volatile cache support mode being deactivated; andnotifying the host device when recording in the non-volatile cache is no longer effective, so that the host device no longer uses the non-volatile cache.

16. A hybrid hard disk drive comprising: a hard disk;a non-volatile cache; anda control portion to control recording of data from a host on the hard disk and the non-volatile cache,wherein the control portion determines whether an erasure number of the non-volatile cache exceeds a usage limit based on the erasure number of the non-volatile cache and permanently deactivates a non-volatile cache support mode when the erasure number of the non-volatile cache is determined to exceed the usage limit.

17. The hybrid hard disk drive of claim 16, wherein the control portion notifies the host device when recording in the non-volatile cache is no longer effective, so that the host device no longer uses the non-volatile cache.

18. A method of a hybrid HDD, the method comprising: detecting a defective block number of a non-volatile cache by detecting the number of defective blocks in the non-volatile cache; and determining that the defective block number is not less than a predetermined threshold value.

19. The method of claim 18, further comprising: remapping the defective blocks;replacing the defective blocks by spare blocks; andincreasing the defective block number.

20. The method of claim 19, further comprising: executing a command given by a host when the defective block number is determined to exceed the predetermined limit block number;deactivating a non-volatile cache support mode; andnotifying the host of the deactivation.

21. A method of a hybrid HDD, the method comprising: permanently deactivating a non-volatile cache mode according to one of an erasure number of a non-volatile cache and the number of defective blocks of the non-volatile cache.

22. A hybrid HDD comprising: an HDD;a non-volatile cache; anda control portion to control the HDD and the non-volatile cache in a non-volatile cache support mode according to an erasure number of the non-volatile cache.