JPH07152623A - File system and its access method - Google Patents

Abstract

PURPOSE:To obtain the file access method whose file retrieval time does not depend upon its storage position without limiting a structuring method for a user's file system by providing original file storage position management information of a file access means separately from the file system that the user structures. CONSTITUTION:When a file 31 is newly accessed, the file access means 17 uses a file retrieval means 20, an indicated file path name is converted by a converting means 21 to obtain its original information 32, and file storage information 30 on a storage device 32 is directly obtained with the information. At this time, the file retrieval means 20 can obtain optional file storage information 30 on the storage device 23 from a storage device 49 by using a function which can make file path names and storage locations 32 correspond to each other unconditionall as the converting means 21. When there are plural storage devices 59, retrieval is performed at a time and the file storage information 30 can be acquired with the information which is obtained most early.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a file system in an information processing apparatus and a method of accessing the file system.

[0002]

2. Description of the Related Art Conventionally, one system has one type of file management structure, and even if there are a plurality of storage devices, the storage format is one. The management structure of the file system was mainly a tree structure.

FIG. 7 shows the concept of a file system having a tree structure. In FIG. 7, 1 is a storage device in which a file system is constructed, 2 is a root node which is the origin of file search, 3 and 4 are directory nodes for managing file storage positions, 5
Is file storage information, 6 is a file entity, 7 is a directory area, 8 is a file entity storage information area, 9 is a file entity storage area, and 1
0 is the general format for directory nodes,
11 is a pointer to the upper directory node, and 1
Reference numerals 2 and 14 are the names of the nodes directly below, and 13 and 15 are pointers to the nodes directly below.

Now, considering the case of accessing a specific file 6, the file management interprets the given file path name "/ A / B / F", reads the root node 2 and reads it from its format 10. Node name A directly below
The entries 12 and 13 corresponding to are searched, the directory node 3 is read based on the pointer 13, and the storage position of the file 6 is searched and accessed in the same manner.

[0005]

A tree-structured file system can flexibly manage a file management system according to a user's request, but the deeper the tree structure is, the more i / o (file Access to the device and the input / output device is required, and there is a problem that the search time becomes long.

Further, in the case of adopting a structure in which all files are arranged immediately below the root node in order to improve performance,
There is a problem that it becomes difficult for the user to distinguish individual files when maintaining and managing the files, and in order to shorten the search time, the file system construction means of the user is limited.

The present invention has been made in view of the above,
It is an object of the present invention to provide a file system and a method of accessing the file system, which does not limit flexible construction of a user's file system and does not cause a difference in search time depending on a storage position of a file to be accessed on the file system. .

[0008]

In order to achieve the above object, a file system of the present invention has a management area for files of different structures in an information processing apparatus having a plurality of storage devices. The point is to share the file entity by storing a pointer to the file storage information in.

The file access method of the present invention is
In an information processing device having a plurality of storage devices, having file management areas for files having different structures, and sharing file entities by storing pointers to file storage information in each file management area,
When a function that converts a file path name is used to secure a unique storage location in the file management area that is associated with the converted value when a file is created, accumulate pointers to the file storage information, and access The gist is to use the above pointer information for.

Further, the file access method of the present invention is
In an information processing device having a plurality of storage devices, having file management areas for files having different structures, and sharing file entities by storing pointers to file storage information in each file management area,
The gist is to dynamically change the structure of a specific file management area according to the frequency of use of the file.

Furthermore, the file access method of the present invention is an information processing apparatus having a plurality of storage devices, having management areas for files of different structures, and storing pointers to file storage information in each file management area. In the file system sharing the file entity by doing so, it has all different file management areas, searches multiple file management areas at the time of file search, and uses the management information of the first detected file. And

[0012]

The file system of the present invention has the management areas for files having different structures, and the file entities are shared by storing pointers to the file storage information in the respective file management areas.

Further, in the file access method of the present invention, a function for converting a file path name is used to secure a unique storage location on the file management area associated with the value converted at the time of file creation, A pointer to the file storage information is accumulated and the pointer information is used when accessing.

Further, in the file access method of the present invention, the structure of the specific file management area is dynamically changed according to the frequency of use of the file.

Further, in the file access method of the present invention, all different file management areas are provided, a plurality of file management areas are searched at the time of file search, and the management information of the first detected file is used.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of the present invention. In the figure, 16 is a central processing unit, 17 is a file access means, 18 is a file system maintenance management means used by a file system maintenance manager, 19 is a file creation means, and 20 is a file. Reference numeral 21 is a searching means, 21 is a file path name converting means, 22 is a means for accessing a storage device, 23 is a storage device for constructing a file system, 24 is a directory management area, and 25 is a file storage. Is an information area, 26 is a file entity area, 27 is a root node, 28 is a directory node with the name A,
Reference numeral 29 is a directory node having a name B, 30 is an information node indicating a storage location of a file entity, 31 is a file entity having a name F, and 32 is a system-specific file management area information for file access. , 59
Is a storage device for storing the information 32.

When a file with the name "F" is created on the storage device 23 as a path name "/ A / B / F", the file access means 17 uses the file creation means 19 to create the directory nodes 28 and 29. Then, a storage area for the file entity 31 is secured, and information on the storage location is stored in the node 30. At the same time, the file access means 1
Reference numeral 7 converts the input path name according to a predetermined conversion rule of the file path name conversion means 21, and stores the instruction information 32 to the file storage information 30 in an appropriate storage location of the storage device 59.

Considering the case of newly accessing the file 31, the file access means 17 uses the file search means 20 to convert the instructed file path name by the conversion means 21 to obtain its unique information 32. Is obtained, and the file storage information 30 on the storage device 23 is directly obtained from the information.

At this time, the file search means 20 serves as the file path name conversion means 21 and stores the file path name and the storage location 3.
The arbitrary file storage information 30 on the storage device 23 can be acquired from the storage device 59 by using a function that uniquely associates 2 with each other. Further, by prioritizing the order of obtaining the management information on the storage device 59, the storage device 2
3, the search time of the file entity can be controlled without changing the directory structure on 3 and when there are a plurality of storage devices 59, the search is performed at a time and the file storage information 30 is obtained from the earliest obtained information. it can.

As described above, by having the file storage location management information unique to the file access means in addition to the file system constructed by the user, the file search time is stored without limiting the user's file system construction method. A location-independent file access method can be provided.

FIG. 2 is a diagram showing another embodiment of the present invention. In this embodiment, as a file path name conversion means, the sum of bit strings turned on in a character string of a file path name is a remainder of 255. A file access method is achieved in which a means for converting to a value is used and a pointer to the storage information of the file entity is stored in the entry on the storage device corresponding to the value.

In FIG. 2, reference numeral 33 is a given file path name, and 34 is, for example, a file path name converted into a JIS code, and the sum of the on bits is 2
55 is a function for obtaining the remainder value of 55, 35 is a storage device storing a file system for maintenance management, and 36, 3
Reference numeral 7 is an input / output block of input / output numbers m and n, 38 is a storage device for storing file storage information for retrieval, and 39 is a pointer to the file storage information 36 (device identifier and input / output number). ) Is stored in the input / output block having the input / output block number 18.

Next, the operation will be described with reference to FIGS. 3 and 4.

Now, consider the case where a file called / A / B / F is created and then accessed. The file F is stored in the input / output block 37 of the block number n on the storage device 35, and the stored information is stored in the input / output block 36 of the block number m (step 140 in FIG. 3). At this time, the file path name "/ A / B / F" is the JIS code 0x2F412F422F46 (the leading "0x" indicates that the following code is written in hexadecimal notation), so "ON" Is 1 + 4 + 1 + 1 + 1 + 4 + 1 + 1 + 1 + 4 + 1 + 2 =
22 and the file path name is converted to a value of 22 (step 141). And the 22nd on the storage device 38
An input / output block is secured (step 142), and the device identifier and the input / output number of the file storage area information of file / A / B / F are saved in the block (step 14).
3).

Thereafter, when accessing the file "/ A / B / F", the file access module converts the file path name into a unique value (step 24 in FIG. 4).
3) Directly refer to the input / output block number 22 on the storage device 38 (step 244), obtain the storage location of the file storage information 36 from that information (step 245), and read the file storage information 36 (step 246). ), The file entity 37 is accessed (step 247). This process is the same for any file in the file system, and i /
You can search the file entity with o.

FIG. 5 is a diagram showing another embodiment of the present invention, which is an example in which priority control of file search is realized. In FIG. 5, reference numeral 40 is a storage device that stores a file system for maintenance management, 41 is a storage device that stores file storage information for retrieval, and 42.
Is an area for storing a pointer to the storage information of a frequently used file, 43 is an area for storing a pointer to the storage information of a less frequently used file, and 44 and 45 are areas 42 respectively. , 43 are the origins of the search, and 46, 47, and 48 are pointers to the file storage information. The pointers are created according to a predetermined rule when the corresponding files are created.

Now, when accessing a file / A / F having a low search priority, the file access means (for example, a file management program) starts the search from the frequently used area 42 in the storage device 41, and then, The area 43 that is not frequently used is searched. When the search is completed, the pointer 48 moves into the area 42. After that, the file is moved between the areas 42 and 43 in response to a file access according to a predetermined rule.

By the above access method, the priority control of the search for each file can be realized without affecting the structure of the file system constructed by the user.

FIG. 6 is a diagram showing still another embodiment of the present invention, which is an example in which file access is realized with an optimum file search time. In FIG. 6, 50 is a file access means (for example, a file management program).
51, 52, and 53 are different file search means, 54 is a storage device that constructs a file system, and 55, 56, and 57 are different embodiments, conventional techniques, and other embodiments. The storage device stores a pointer to the file storage information described above, and 58 is a file entity.

Now, when accessing a file / A / B / F, the file access means 50 activates the file search means 51, 52, 53 at a time, and the storage devices 54, 55,
Access 57. Then, the file entity 58 is accessed based on the information of the search means that has completed the search earliest.

In this embodiment, the pointer storage structure in the storage device is not limited to the type of this embodiment, and the number of storage devices is also not limited. Also, the file access means 5
0 and the storage devices 54, 55, 57 may be physically separated from each other, and the target file can be searched and accessed at an optimum time according to the environment.

As described above, the file system of the present invention has, in addition to the file management area that the user is aware of, the file management area that the system is aware of and that is stored in the file system by the user. Its main feature is that it has a unique management structure for file entities. This is different from the conventional technique in that a single file system has a plurality of file management areas having different structures, and that file entities are shared by the respective management areas.

Further, in the access method of the present invention, the file system for maintenance management such as file creation and directory creation provides the management structure of the prior art, and at the same time, refers to the created file at the next access. The unique information of the file is stored in a separate file management area, and when the user makes an access request, the file is searched and accessed using the unique management information based on the file path name specified by the user. Is the main feature. With conventional technology, for one file system,
The difference is that it has a file path that the user is aware of for maintenance and a search means for another file at the same time.

[0035]

As described above, according to the present invention,
By having a plurality of file management areas with different structures, it is possible to reduce the number of accesses to the storage device without limiting the construction of the user's file system, and for file search and access regardless of the file storage location. Therefore, it is possible to reduce the variation in time. Furthermore, the priority of file search can be controlled without affecting the structure of the file system constructed by the user, and the file storage information can be stored in multiple storage devices. You can search files in time.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing another embodiment of the present invention.

FIG. 3 is a flowchart showing an operation when creating a file in the embodiment of FIG.

FIG. 4 is a flowchart showing an operation when accessing a file in the embodiment of FIG.

FIG. 5 is a diagram showing another embodiment of the present invention.

FIG. 6 is a diagram showing still another embodiment of the present invention.

FIG. 7 is a diagram showing a concept of a file system having a tree structure.

[Explanation of symbols]

 16 central processing unit 17 file access means 18 file system maintenance management means 19 file creation means 20 file search means 21 file path name conversion means 23, 59 storage device 27 root node 28, 29 directory node 30 information node 31 file entity

Claims (4)

[Claims] 1. An information processing apparatus having a plurality of storage devices, having file management areas of different structures, and sharing file entities by storing pointers to file storage information in the respective file management areas. File system characterized by. 2. An information processing device having a plurality of storage devices, which has management areas for files having different structures, and shares file entities by storing pointers to file storage information in the respective file management areas. In the system, a function that converts the file path name is used, a unique storage location in the file management area that is associated with the converted value when the file is created is secured, and a pointer to the file storage information is accumulated. A file access method characterized in that the pointer information is used when accessing. 3. An information processing device having a plurality of storage devices, which has management areas for files having different structures, and which shares a file entity by storing pointers to file storage information in each file management area. In the system, a file access method characterized by dynamically changing the structure of a specific file management area according to the frequency of use of the file. 4. An information processing device having a plurality of storage devices, having files having different structure management areas, and sharing a file entity by storing a pointer to file storage information in each file management area. A file access method characterized by having all different file management areas in a system, searching a plurality of file management areas at a time when searching for a file, and using management information of the file detected first.