File system having transaction record coalescing

• US 20070005627A1
• Filed: 06/09/2006
• Published: 01/04/2007
• Est. Priority Date: 07/01/2005
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: QNX Software Systems Limited (Canada) (Blackberry Limited)
• Inventors: Dodge, Dan
• Granted Patent: US 7,873,683 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/50 of still image data

Abstract

An electronic data system comprises memory storage having stored data, file system software, and a transaction file. The transaction file is maintained by the file system software, and includes a plurality of transaction records corresponding to transactions that have been or are to be executed on one or more files and/or the or more directories of the file system. The file system software operates to organize and maintain the stored data in the files and directories and also to coalesce multiple transaction records meeting one or more criteria into fewer coalesced transaction records. The physical memory space required by the transaction file is reduced by the transaction record coalescing. The coalesced transaction records may be constructed so that they represent a logical result of applying each transaction record of a transaction record set in chronological order. Once the coalesced transaction records have been committed in the file system, the physical memory used by the original transaction records in the set may be reclaimed for further use (e.g., to store further transaction records) or may be otherwise removed from further use (e.g., when the physical memory is located in a block of memory in a flash-like memory device that has reached its maximum number of write and/or erase cycles).

Claims

1. An electronic data system comprising:

memory storage having stored data;

file system software adapted to organize and maintain the stored data in one or more files and one or more directories;

a transaction file maintained by the file system software, the transaction file comprising a plurality of transaction records corresponding to transactions that have been or are to be executed on the one or more files and/or the one or more directories;

where the file system software coalesces multiple transaction records meeting one or more criteria into fewer coalesced transaction records.

2. The electronic data system of claim 1 where the file system software assigns one or more transaction identifiers to the coalesced transaction records.

3. The electronic data system of claim 1 where the file system software generates one or more transaction record sets corresponding to transaction records meeting the one or more criteria, where the one or more transaction record sets are used by the file system to generate the fewer coalesced transaction records.

4. The electronic data system of claim 3 where the one or more transaction record sets comprise pointers to locations of individual transaction records in the transaction file.

5. The electronic data system of claim 3 where the one or more transaction record sets comprise groups of transaction records, where each transaction record of a group is formatted in a manner substantially similar to a manner in which a corresponding individual transaction record is formatted in the transaction file.

6. The electronic data system of claim 1 where the persistent data storage device comprises flash-like memory.

7. The electronic data system of claim 6 where the transaction file is stored in the memory storage.

8. The electronic data system of claim 1 where the fewer coalesced transaction records occupy less physical storage space in the transaction file than the physical storage space occupied in the transaction file by the multiple transaction records that meet the one or more criteria.

9. The electronic data system of claim 1 where the file system software coalesces multiple transaction records that correspond to the same file.

10. The electronic data system of claim 1 where the file system software coalesces multiple transaction records that correspond to the same file to generate a single transaction record in the transaction file.

11. The electronic data system of claim 10 where the file system software applies the multiple transaction records in a chronological sequence for coalescing into the fewer coalesced transaction records, and where the chronological sequence in which the multiple transaction records are applied corresponds to a time order in which each transaction record of the multiple transaction records originally occurred.

12. The electronic data system of claim 1 where the file system software reclaims residual physical storage space that results from coalescing the multiple transaction records into the fewer coalesced transaction records.

13. The electronic data system of claim 12 where the file system software reclaims the residual physical storage space to store further transaction records.

14. The electronic data system of claim 8 where the file system software reclaims residual physical storage space that results from coalescing the multiple transaction records into the fewer coalesced transaction records.

15. The electronic data system of claim 14 where the file system software reclaims the residual physical storage space to store further transaction records.

16. An electronic data system comprising:

flash-like memory having stored data;

file system software adapted to organize and maintain the stored data in one or more files and one or more directories;

a transaction file maintained by the file system software, the transaction file comprising a plurality of transaction records stored on the flash-like memory where the transaction records correspond to transactions that have been or are to be executed on the one or more files and/or the one or more directories; and

where the file system software coalesces multiple transaction records directed to the same file, the same logical portion of a file and/or the same directory into fewer coalesced transaction records for the same file, the same logical portion of a file and/or the same directory.

17. The electronic data system of claim 16 where the file system software assigns one or more transaction identifiers to the coalesced transaction records.

18. The electronic data system of claim 16 where the file system software generates one or more transaction record sets corresponding to transaction records meeting one or more criteria, where the one or more transaction record sets are used by the file system to generate the fewer coalesced transaction records.

19. The electronic data system of claim 18 where the one or more transaction record sets comprise pointers to locations of individual transaction records in the transaction file.

20. The electronic data system of claim 18 where the one or more transaction record sets comprise groups of transaction records, where each transaction record of a group is formatted in a manner substantially similar to a manner in which a corresponding individual transaction record is formatted in the transaction file.

21. The electronic data system of claim 16 where the fewer coalesced transaction records occupy less physical storage space in the transaction file than the physical storage space occupied in the transaction file by the multiple transaction records that meet the one or more predetermined criteria.

22. The electronic data system of claim 16 where the file system software coalesces multiple transaction records that correspond to the same file, the same logical portion of a file, and/or the same directory to generate a single transaction record in the transaction file for the same file, the same logical portion of the file, and/or the same directory, respectively.

23. The electronic data system of claim 16 where the file system software applies the multiple transaction records in a chronological sequence for coalescing into the fewer coalesced transaction records, and where the chronological sequence in which the multiple transaction records are applied corresponds to a time order in which each transaction record of the multiple transaction records originally occurred.

24. The electronic data system of claim 16 where the file system software reclaims residual physical storage space that results from coalescing the multiple transaction records into the fewer coalesced transaction records.

25. The electronic data system of claim 24 where the file system software reclaims the residual physical storage space to store further transaction records.

26. A computer system comprising:

a processor;

memory storage accessible by the processor;

file system software executable by the processor to manage file data and file system structure of data stored on the memory storage;

a transaction file maintained by the file system software, the transaction file comprising a plurality of transaction records corresponding to files stored on the memory storage;

where the file system software coalesces multiple transaction records meeting one or more criteria into fewer coalesced transaction records; and

where the fewer coalesced transaction records occupy less physical storage space in the transaction file than the physical storage space occupied by the multiple transaction records in the transaction file that meet the one or more criteria.

27. The computer system of claim 26 where the file system software coalesces multiple transaction records that correspond to the same file, the same logical portion of a file, and/or the same directory.

28. The computer system of claim 26 where the file system software coalesces multiple transaction records that correspond to the same file, the same logical portion of the file, and/or the same directory to generate a single transaction record in the transaction file for the same file, the same logical portion of a file, and/or the same directory, respectively.

29. The computer system of claim 28 where the file system software applies the multiple transaction records in a chronological sequence for coalescing into the fewer coalesced transaction records, and where the chronological sequence in which the multiple transaction records are applied corresponds to a time order in which each transaction record of the multiple transaction records originally occurred.

30. A computer readable medium having computer-executable instructions for performing a method comprising:

organizing and maintaining data stored on memory storage device in files and directories;

maintaining a transaction file comprising a plurality of transaction records corresponding to transactions that have been or are to be executed on the logical files and/or the logical directories; and

coalescing multiple transaction records meeting one or more predetermined criteria into fewer coalesced transaction records.

31. The computer readable medium of claim 30 where the coalescing operation comprises generating one or more transaction record sets corresponding to transaction records meeting the one or more criteria, where the one or more transaction record sets are used by the file system to generate the fewer coalesced transaction records.

32. The computer readable medium of claim 31 where the one or more transaction record sets comprise pointers to locations of individual transaction records in the transaction file.

33. The computer readable medium of claim 31 where the one or more transaction record sets comprise groups of transaction records, where each transaction record of a group is formatted in a manner substantially similar to a manner in which a corresponding individual transaction record is formatted in the transaction file.

34. The computer readable medium of claim 30 where the coalescing operation is executed on multiple transaction records that correspond to the same file, the same logical portion of a file, and/or at the same directory.

35. The computer readable medium of claim 30 where the method further includes reclaiming residual physical storage space that results from coalescing the multiple transaction records into the fewer coalesced transaction records.

36. The electronic data system of claim 35 where the reclaimed residual physical storage space is used to store further transaction records.