Method of managing data of file system using database management

Abstract

A method of managing data of a file system using a database management system is provided. According to the method, the metadata of the file system is managed using a database management system (DBMS), but writing data to or reading data from a disk is directly performed by the file system according to the method directly performed not through other file systems or DBMSs. In this way, stable transactions are guaranteed for a user, and the user can design a disk allocation algorithm optimized with respect to a multimedia environment.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:

FIG. 1 is a block diagram illustrating a structure of a related art file system for managing metadata using a database;

FIG. 2 is a flowchart illustrating a process of storing data on a disk in a file system according to an exemplary embodiment of the present invention;

FIG. 3 illustrates a schema of a database storing metadata of a file system according to an exemplary embodiment of the present invention;

FIG. 4 is a block diagram illustrating a file system according to an exemplary embodiment of the present invention;

FIG. 5 is a diagram illustrating a process of creating a file in a file system according to an exemplary embodiment of the present invention;

FIG. 6 is a diagram illustrating a process of writing a file in a file system according to an exemplary embodiment of the present invention; and

FIG. 7 is a diagram illustrating a process of reading a file in a file system according to an exemplary embodiment of the present invention.

Claims

1. A method of managing data in a file system comprising: searching for a free disk space by using a database management system (DBMS) managing metadata of the file system, when a data write request is received from an application;writing the data in the free disk space without involvement of the DBMS, by referring to the search result; andupdating a part of the metadata changing with the data being written, by using the DBMS.

2. The method of claim 1, wherein all operations from the searching operation to the updating operation are managed by the DBMS as one transaction.

3. The method of claim 1, wherein the file system operates at a user level.

4. The method of claim 1, wherein a disk on which the data is stored is different from a disk on which the metadata is stored.

5. The method of claim 1, wherein the updating of the part of the metadata comprises requesting the DBMS to update at least one of a database table containing information about a free space, a database table containing information about a non-free space, and a database table containing information about an inode.

6. The method of claim 1, wherein the metadata expresses information about a free space of a disk in the form of an extent.

7. The method of claim 6, wherein the extent form is expressed with a block number indicating a start position of the free space and the number of blocks corresponding to the size of the free space.

8. The method of claim 6, wherein the extent form is expressed with a byte offset indicating a start position of the free space and a byte unit indicating the size of the free space.

9. The method of claim 1, further comprising: obtaining metadata related to the data through the DBMS, when a read request of the data is received from an arbitrary application;reading data of at least one block determined by the obtained metadata from a disk not through the DBMS; andtransferring the read data to the arbitrary application.

10. A computer readable recording medium storing a computer program for performing a method of managing data in a file system comprising: searching for a free disk space by using a database management system (DBMS) managing metadata of the file system, when a data write request is received from an application;writing the data in the free disk space without involvement of the DBMS, by referring to the search result; andupdating a part of the metadata changing with the data being written, by using the DBMS.