Timeline application for log structured storage devices

• US 8,554,741 B1
• Filed: 06/16/2010
• Issued: 10/08/2013
• Est. Priority Date: 06/16/2010
• 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: Malina, James N.
• Primary Examiner(s): LIAO, JASON G
• Application Number:
  US12/816,920
• Time in Patent Office: 1,210 Days
• Field of Search: None
• US Class Current: 707/674
• CPC Class Codes: G06F 11/14 Error detection or correction of the data by redundancy in operation G06F11/16 takes precedence
• CPC Class Codes: G06F 11/1471 involving logging of persistent data for recovery
• CPC Class Codes: G06F 7/00 Methods or arrangements for processing data by operating upon the order or content of the data handled logic circuits H03K19/00

Abstract

A host computer receives log structured data from a data storage device (DSD), wherein the log structured data comprises logical block addresses (LBAs) corresponding to a plurality of write operations performed on the DSD, and the log structured data comprises at least one duplicated instance of an LBA, wherein each instance of the LBA represents a different write operation. Timeline information related to the log structured data is displayed in an accounting window.

Claims

1. A non-transitory computer readable storage medium comprising code segments of a timeline application, the code segments, which when executed by a computer processor, cause the computer processor to:

receive log structured data from a data storage device (DSD), wherein;

the log structured data comprises logical block addresses (LBAs) corresponding to a plurality of write operations performed on the DSD;

the log structured data maps each LBA to a physical block address (PBA); and

the log structured data comprises at least one duplicated instance of an LBA, wherein each instance of the LBA represents a different write operation;

store an LBA map mapping at least one LBA to a PBA;

command the DSD to roll the stored LBA map from a current state to a previous state corresponding to an entry in the log structured data by specifying a PBA in the log structured data corresponding to the previous state of the stored LBA map; and

display timeline information related to the log structured data in an accounting window.

2. The non-transitory computer readable storage medium as recited in claim 1, wherein each instance of the LBA in the log structured data is mapped to a different PBA.

3. The non-transitory computer readable storage medium as recited in claim 1, wherein the code segments are further operable to evaluate the log structured data to identify modifications to file system data.

4. The non-transitory computer readable storage medium as recited in claim 3, wherein the accounting window displays the modifications to the file system data.

5. The non-transitory computer readable storage medium as recited in claim 3, wherein the code segments are further operable to identify LBAs assigned to the file system data.

6. The non-transitory computer readable storage medium as recited in claim 5, wherein the code segments are further operable to identify the LBAs assigned to the file system data by:

commanding the DSD to roll the stored LBA map to an initial state; and

reading the file system data from the DSD.

7. The non-transitory computer readable storage medium as recited in claim 5, wherein the code segments are further operable to:

evaluate the log structured data to determine when an LBA of the file system data has been duplicated; and

read the corresponding modified file system data from the DSD.

8. The non-transitory computer readable storage medium as recited in claim 7, wherein the code segments are further operable to read the corresponding modified file system data from the DSD by reading a PBA from the DSD corresponding to the duplicated LBA.

9. The non-transitory computer readable storage medium as recited in claim 7, wherein the code segments are further operable to read the corresponding modified file system data from the DSD by:

commanding the DSD to roll the stored LBA map to a state when the LBA was duplicated; and

read the LBA from the DSD.

10. The non-transitory computer readable storage medium as recited in claim 1, wherein the code segments are further operable to command the DSD to roll the stored LBA map to the state corresponding to the entry of the log structured data in response to a user selecting an entry from the accounting window.

11. The non-transitory computer readable storage medium as recited in claim 1, wherein the code segments are further operable to:

select a target LBA from the log structured data; and

transmit a read command to the DSD comprising the target LBA and a write operation identifier that identifies when the target LBA was written by the DSD.

12. The non-transitory computer readable storage medium as recited in claim 1, wherein the log structured data comprises at least one environmental condition at the time of each write operation.

13. The non-transitory computer readable storage medium as recited in claim 1, wherein the log structured data comprises location information at the time of each write operation.

14. The non-transitory computer readable storage medium as recited in claim 1, wherein the code segments are further operable to command the DSD to generate a log structured data file comprising the log structured data for a plurality of the write operations.

15. The non-transitory computer readable storage medium as recited in claim 1, wherein the code segments are further operable to display timeline information related to the log structured data for a particular file.

16. The non-transitory computer readable storage medium as recited in claim 1, wherein the log structured data includes a sequence number or a date for each LBA.

17. A method of operating a host computer, the host computer coupled to a data storage device (DSD), the method comprising:

receiving log structured data from the DSD, wherein;

the log structured data comprises logical block addresses (LBAs) corresponding to a plurality of write operations performed on the DSD;

the log structured data maps each LBA to a physical block address (PBA); and

the log structured data comprises at least one duplicated instance of an LBA, wherein each instance of the LBA represents a different write operation;

commanding the DSD to roll a stored LBA map from a current state to a previous state corresponding to an entry in the log structured data by specifying a PBA in the log structured data corresponding to the previous state of the stored LBA map, wherein the stored LBA map maps at least one LBA to a PBA; and

displaying timeline information related to the log structured data in an accounting window.

18. The method as recited in claim 17, wherein each instance of the LBA in the log structured data is mapped to a different PBA.

19. The method as recited in claim 17, further comprising evaluating the log structured data to identify modifications to file system data.

20. The method as recited in claim 19, wherein the accounting window displays the modifications to the file system data.

21. The method as recited in claim 19, further comprising identifying LBAs assigned to the file system data.

22. The method as recited in claim 21, wherein identifying the LBAs assigned to the file system data comprises:

commanding the DSD to roll the stored LBA map to an initial state; and

reading the file system data from the DSD.

23. The method as recited in claim 21, further comprising:

evaluating the log structured data to determine when an LBA of the file system data has been duplicated; and

reading the corresponding modified file system data from the DSD.

24. The method as recited in claim 23, further comprising reading the corresponding modified file system data from the DSD by reading a PBA from the DSD corresponding to the duplicated LBA.

25. The method as recited in claim 23, further comprising reading the corresponding modified file system data from the DSD by:

commanding the DSD to roll the stored LBA map to a state when the LBA was duplicated; and

reading the LBA from the DSD.

26. The method as recited in claim 17, further comprising commanding the DSD to roll the stored LEA map to the state corresponding to the entry of the log structured data in response to a user selecting an entry from the accounting window.

27. The method as recited in claim 17, further comprising:

selecting a target LEA from the log structured data; and

transmitting a read command to the DSD comprising the target LEA and a write operation identifier that identifies when the target LEA was written by the DSD.

28. The method as recited in claim 17, wherein the log structured data comprises at least one environmental condition at the time of each write operation.

29. The method as recited in claim 17, wherein the log structured data comprises location information at the time of each write operation.

30. The method as recited in claim 17, further comprising commanding the DSD to generate a log structured data file comprising the log structured data for a plurality of the write operations.

31. The method as recited in claim 17, wherein displaying timeline information includes displaying LBA information related to the log structured data for a particular file.

32. The method as recited in claim 17, wherein the log structured data includes a sequence number or a date for each LBA.

33. A data storage device (DSD) comprising:

a non-volatile memory comprising a plurality of memory segments, wherein a physical block address (PBA) is assigned to each memory segment; and

control circuitry operable to;

execute a first and a second write operation for a target logical block address (LBA), wherein the first write operation writes data to a first PBA, and the second write operation writes data to a second PBA;

maintain log structured data for the first and second write operations, including the LBA and the first and second PBAs;

transmit at least part of the log structured data to a host computer;

store an LBA map for mapping the LBA to the first and second PBAs; and

roll the stored LBA map from a current state to a previous state corresponding to an entry in the log structured data representing one of the first and second write operations by specifying the first PBA or the second PBA in the log structured data in response to a command received from the host computer.

34. The DSD as recited in claim 33, wherein the log structured data comprises a date of the first and second write operations.

35. The DSD as recited in claim 33, wherein the log structured data comprises a sequence number of the first and second write operations.

36. The DSD as recited in claim 33, wherein the control circuitry is further operable to:

receive a read command from the host computer, wherein the read command comprises a target LBA and a write operation identifier;

search the log structured data for a target PBA corresponding to the target LBA and the write operation identifier; and

return the target PBA to the host computer.

37. The DSD as recited in claim 36, wherein the write operation identifier comprises one of a date and a sequence number.

38. The DSD as recited in claim 33, wherein the log structured data comprises at least one environmental condition at the time of each write operation.

39. The DSD as recited in claim 33, wherein the log structured data comprises location information at the time of each write operation.

40. The DSD as recited in claim 33, wherein the control circuitry is further operable to generate a log structured data file comprising the log structured data for a plurality of write operations.