File management program, file management apparatus and file management method

• US 20070038689A1
• Filed: 02/01/2006
• Published: 02/15/2007
• Est. Priority Date: 08/03/2005
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Shinkai, Yoshitake
• Granted Patent: US 7,680,846 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/119 Details of migration of file systems migration mechanisms in storage systems G06F3/0647
• CPC Class Codes: Y10S 707/99956 File allocation

Abstract

The present invention has been made to provide a file management program, a file management apparatus, and a file management method capable of migrating files between file systems while an application program is being run. A file management program allowing a computer to manage files on a plurality of file systems, the program allowing the computer to execute: a file information retrieve step that acquires the file information of source files on source file system and records the acquired file information as a file information event; a file operation trace step that acquires the information of file operation made for the source files and records the acquired file operation as a file operation event; and a namespace replication step that generates, based on the file information event and file operation event, a namespace replication database in which the namespace of the source files has been replicated logically.

Claims

1. A file management program allowing a computer to manage files on a plurality of file systems, the program allowing the computer to execute:

a file information retrieve step that acquires the file information of source files on source file system and records the acquired file information as a file information event;

a file operation trace step that acquires the information of file operation made for the source files and records the acquired file operation as a file operation event; and

a namespace replication step that generates, based on the file information event and file operation event, a namespace replication database in which the namespace of the source files has been replicated logically.

2. The file management program according to claim 1, allowing the computer to further execute after the namespace replication step:

a file data replication step that sets a directory on destination file system based on the namespace replication database and replicates data of the source files from the source file system to destination file system.

3. The file management program according to claim 2, wherein

the file data replication step reflects unprocessed file operation events on the destination file system and provides an instruction for performing a file system switch step when the amount of the unprocessed file operation events becomes less than a predetermined amount.

4. The file management program according to claim 2, allowing the computer to further execute after the file data replication step:

a file system switch step that switches an access made to the source files on the source file system to an access made to the source files on the destination file system.

5. The file management program according to claim 4, wherein

the file system switch step temporarily blocks a file access, reflects unprocessed file operation events on the destination file system, sets link information to the destination file system, and cancels the file access suspension after completion of file system switch.

6. The file management program according to claim 1, wherein

the file information retrieve step follows a hierarchical structure of a directory on the source file system in the ascending or descending order in terms of path name and records file information including the name and attribute of the source files.

7. The file management program according to claim 1, wherein

the namespace replication step determines the actual sequence among the file information events and file operation events and reflects the content of the succeeding file operation event on the content of the file information event according to the determined occurrence order to thereby generate the right namespace replication database.

8. The file management program according to claim 1, wherein

in the case where the common information acquitition time of the file information event and file operation event, that specifies exact sequence among mulitple events, cannot be acquired from the source file system, the file information retrieve step or file operation trace step sets the information acquisition time field in the event to the current time, and

the namespace replication step estimates the right sequence of given two events, using a pre-defined maximum possible time lag, in which an event having a maximun possible time lag smaller information acquisition time than the counterpart, is deemed to precede the other.

9. The file management program according to claim 1, wherein

in the case where the order of ocurrence between the file information events and file operation events cannot be determined, the namespace replication step sets a file or directory that is likely to have been created as a candidate, determines existence of the candidate basen on the succeeding file information event and file operation event, in which in the case where existence of the candidate has been determined, the namespace replication step registers the candidate in the namespace replication database;

whereas in the case where the existence of the candidate has not been determined, the namespace replication step inquires of the source file system for the existence of the candidate and registers the candidate whose existence has been determined in the namespace replication database.

10. A file management apparatus that manages files on a plurality of file systems, comprising:

a file information retrieve section that acquires the file information of source files on source file system and records the acquired file information as a file information event;

a file operation trace section that acquires the information of file operation made for the source files and records the acquired file operation as a file operation event; and

a namespace replication section that generates, based on the file information event and file operation event, a namespace replication database in which the namespace of the source files has been replicated logically.

11. The file management apparatus according to claim 10, further comprising:

a file data replication section that sets a directory on destination file system based on the namespace replication database and replicates data of the source files from the source file system to destination file system.

12. The file management apparatus according to claim 11, wherein

the file data replication section reflects unprocessed file operation events on the destination file system and provides an instruction for performing a file system switch section when the amount of the unprocessed file operation events becomes less than a predetermined amount.

13. The file management apparatus according to claim 11, further comprising:

a file system switch section that switches an access made to the source files on the source file system to an access made to the source files on the destination file system.

14. The file management apparatus according to claim 13, wherein

the file system switch section temporarily blocks a file access, reflects unprocessed file operation events on the destination file system, sets link information to the destination file system, and cancels the file access suspension after completion of file system switch.

15. The file management apparatus according to claim 10, wherein

the file information retrieve section follows a hierarchical structure of a directory on the source file system in the ascending or descending order in terms of path name and records file information including the name and attribute of the source files.

16. The file management apparatus according to claim 10, wherein

the namespace replication section determines the actual sequence among the file information events and file operation events and reflects the content of the succeeding file operation event on the content of the file information event according to the determined occurrence order to thereby generate the namespace replication database.

17. The file management apparatus according to claim 10, wherein

in the case where the common information acquitition time of the file information event and file operation event, that specifies exact sequence among mulitple events, cannot be acquired from the source file system, the file information retrieve section or file operation trace section sets the information acquisition time field in the event to the current time, and

the namespace replication section estimates the right sequence of given two events, using a pre-defined maximum possible time lag, in which an event having a maximun possible time lag smaller information acquisition time than the time of the counterpart, is deemed to precede the other.

18. A file management method that manages files on a plurality of file systems with a computer, comprising:

a file information retrieve step that acquires the file information of source files on source file system and records the acquired file information as a file information event;

a file operation trace step that acquires the information of file operation made for the source files and records the acquired file operation as a file operation event; and

a namespace replication step that generates, based on the file information event and file operation event, a namespace replication database in which the namespace of the source files has been replicated logically.

19. The file management method according to claim 18, further comprising after the namespace replication step:

a file data replication step that sets a directory on destination file system based on the namespace replication database and replicates data of the source files from the source file system to destination file system.

20. The file management method according to claim 19, further comprising after the file data replication step:

a file system switch step that switches an access made to the source files on the source file system to an access made to the source files on the destination file system.