Non-volatile caching for sequence of data

• US 9,123,382 B1
• Filed: 10/28/2014
• Issued: 09/01/2015
• Est. Priority Date: 10/28/2014
• Status: Active Grant

• Current Assignee: JP Morgan Chase Bank, N.A. (JP Morgan Chase & Co)
• Original Assignee: Western Digital Technologies Incorporated (Western Digital Corporation)
• Inventors: Abasto, Erick Omar
• Primary Examiner(s): Dinh, Tan X
• Application Number:
  US14/526,134
• Time in Patent Office: 308 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G11B 20/10527 Audio or video recording; Data buffering arrangements G11B20/12 - G11B20/18 take precedence
• CPC Class Codes: G11B 27/034 on discs G11B27/036, G11B27/038 take precedence
• CPC Class Codes: G11B 27/36 Monitoring, i.e. supervising the progress of recording or reproducing for digital recording G11B20/00 and s.gr.; for monitoring, testing or measuring of TV recorders of the type covered by H04N5/76 and subgroups, see H04N17/06

Abstract

Operation of a Data Storage Device (DSD) including a Non-Volatile Semiconductor Memory (NVSM) and at least one disk. A size value is determined corresponding to a sequence of data to be read from or stored in the DSD. If the size value is less than a threshold value, the sequence of data is stored in the NVSM. If the size value is greater than the threshold value, a first portion of the sequence of data is stored in the NVSM and at least a remaining portion of the sequence of data is stored on the at least one disk. The threshold value is based on at least a preparation time for accessing data from the at least one disk and a throughput value of the NVSM for storing data in or retrieving data from the NVSM.

Claims

1. A Data Storage Device (DSD), comprising:

at least one disk for storing data;

at least one head for reading data from or storing data on the at least one disk;

a Non-Volatile Semiconductor Memory (NVSM) for storing data; and

a controller configured to;

determine a size value corresponding to a sequence of data to be read from or stored in the DSD;

if the size value is less than a threshold value, store the sequence of data in the NVSM; and

if the size value if greater than the threshold value, store a first portion of the sequence of data in the NVSM and control the at least one head to store at least a remaining portion of the sequence of data on the at least one disk;

wherein the threshold value is based on at least;

a preparation time for accessing data on the at least one disk, and

a throughput value of the NVSM for storing data in or retrieving data from the NVSM.

2. The DSD of claim 1, wherein the size value corresponds to an amount of data to be read from or stored in the DSD.

3. The DSD of claim 1, wherein the size value corresponds to a number of queued commands for reading data from or storing data in the DSD.

4. The DSD of claim 1, wherein the size value of the first portion of the sequence of data is equal to the threshold value.

5. The DSD of claim 1, wherein the first portion of the sequence of data is stored in both the at least one disk and the NVSM.

6. The DSD of claim 1, wherein if the sequence of data is accessed after storing the first portion of the sequence of data in the NVSM and storing the at least a remaining portion of the sequence of data on the at least one disk, the controller is further configured to:

read the first portion of the sequence of data from the NVSM during the preparation time for accessing data from the at least one disk, and

prepare to read the at least a remaining portion of the sequence of data from the at least one disk while the first portion of the sequence of data is read from the NVSM.

7. The DSD of claim 1, wherein the controller is further configured to synchronize reading or storing the first portion of the sequence of data in the NVSM with reading or storing the at least a remaining portion of the sequence of data on the at least one disk.

8. The DSD of claim 1, wherein the controller is further configured to store the sequence of data in the NVSM if the size value equals the threshold value.

9. The DSD of claim 1, wherein the controller is further configured to store the first portion of the sequence of data in the NVSM and control the at least one head to store the at least a remaining portion of the sequence of data on the at least one disk if the size value equals the threshold value.

10. A method of operating a Data Storage Device (DSD) including a Non-Volatile Semiconductor Memory (NVSM) and at least one disk, the method comprising:

determining a size value corresponding to a sequence of data to be read from or stored in the DSD;

if the size value is less than a threshold value, storing the sequence of data in the NVSM; and

if the size value is greater than the threshold value, storing a first portion of the sequence of data in the NVSM and storing at least a remaining portion of the sequence of data on the at least one disk;

wherein the threshold value is based on at least;

a preparation time for accessing data from the at least one disk, and

a throughput value of the NVSM for storing data in or retrieving data from the NVSM.

11. The method of claim 10, wherein the size value corresponds to an amount of data to be read from or stored in the DSD.

12. The method of claim 10, wherein the size value corresponds to a number of queued commands for reading data from or storing data in the DSD.

13. The method of claim 10, wherein the size value of the first portion of the sequence of data is equal to the threshold value.

14. The method of claim 10, wherein the first portion of the sequence of data is stored in both the at least one disk and the NVSM.

15. The method of claim 10, wherein if the sequence of data is accessed after storing the first portion of the sequence of data in the NVSM and storing the at least a remaining portion of the sequence of data on the at least one disk, the method further comprises:

reading the first portion of the sequence of data from the NVSM during the preparation time for accessing data from the at least one disk, and

preparing to read the at least a remaining portion of the sequence of data from the at least one disk while the first portion of the sequence of data is read from the NVSM.

16. The method of claim 10, further comprising synchronizing reading or storing the first portion of the sequence of data in the NVSM with reading or storing the at least a remaining portion of the sequence of data on the at least one disk.

17. The method of claim 10, further comprising storing the sequence of data in the NVSM if the size value equals the threshold value.

18. The method of claim 10, further comprising storing the first portion of the sequence of data in the NVSM and storing the at least a remaining portion of the sequence of data on the at least one disk if the size value equals the threshold value.

19. A host in communication with a Data Storage Device (DSD) including at least one disk for storing data and a Non-Volatile Semiconductor Memory (NVSM) for storing data, the host comprising:

an interface for communicating with the DSD; and

a processor configured to;

determine a size value corresponding to a sequence of data to be read from or written to the DSD;

if the size value is less than a threshold value, store the sequence of data in the NVSM; and

if the size value is greater than the threshold value, store a first portion of the sequence of data in the NVSM and at least a remaining portion of the sequence of data on the at least one disk;

wherein the threshold value is based on at least;

a preparation time for accessing data from the at least one disk, and

a throughput value of the NVSM for storing data in or retrieving data from the NVSM.

20. The host of claim 19, wherein the size value corresponds to an amount of data to be read from or written to the DSD.

21. The host of claim 19, wherein the size value corresponds to a number of queued commands for reading data from or writing data to the DSD.

22. The host of claim 19, wherein the size value of the first portion of the sequence of data is equal to the threshold value.

23. The host of claim 19, wherein the first portion of the sequence of data is stored in both the at least one disk and the NVSM.

24. The host of claim 19, wherein the processor is further configured to store the sequence of data in the NVSM if the size value equals the threshold value.

25. The host of claim 19, wherein the processor is further configured to store the first portion of the sequence of data in the NVSM and store the at least a remaining portion of the sequence of data on the at least one disk if the size value equals the threshold value.