JP2767966B2 - High-speed file access method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a file access method in an information processing system, and more particularly to a high-speed file access method for accessing a data file at a high speed using a high-speed file device.

[Conventional technology]

Conventionally, the speed of file access using such a high-speed file device has been increased by securing all data files in a high-speed file device having a high access speed.

[Problems to be solved by the invention]

In the conventional method for accelerating file access described above,
If a large-capacity data file needs to be accessed at high speed, all of the data files must be secured on the high-speed file device, so the number of high-speed file devices corresponding to the capacity of the data file is required. In addition, there is a drawback that a part of the data file that is not frequently accessed is secured on an expensive high-speed file device.

SUMMARY OF THE INVENTION In view of the above, it is an object of the present invention to keep only an updated image of a page updated in a data file on a high-speed file device and to match an updated image of a page updated from a user program with another Another object of the present invention is to provide a high-speed file access method which enables a user program to be referred to and updated, thereby enabling high-speed access to a data file while effectively utilizing a high-speed file device.

[Means for solving the problem]

The high-speed file access method of the present invention performs processing while simultaneously accessing data files in a file access method for a data file that is used by a plurality of user programs, is subjected to exclusive control in page units, and can be accessed simultaneously. A plurality of user programs, the data file accessed by the plurality of user programs, a file device in which the data file is located, and an updated image in which the page of the data file is updated by the user program Update data file comprising a plurality of update data sub-files storing the update data file, a high-speed file device in which the update data file is placed and which can be accessed at a higher speed than the file device, and information on a page updated by the user program And update a A page management table that manages the location information of the update data subfile storing the page in a program table and a shared table that can be used by all of the user programs. File processing means which is called by a user program and transfers control to processing means corresponding to each processing of starting use of the data file, inputting / outputting to / from the data file and ending use of the data file; Called, the update data subfile is secured on the high-speed file device in correspondence with the user program in the use start processing of the data file, and the position information of the secured update data subfile is registered as a program table in the page management table. File use start means, and the file In response to a request to refer to a page of the data file, the page management table is searched to determine whether or not there is an update image of the corresponding page in the update data subfile. If there is an update image, read the corresponding page update image from the update data subfile at high speed.If there is no update image of the corresponding page in the update data subfile, perform a process of reading the corresponding page from the data file. File input / output means for reflecting the updated page information in the page management table and storing an updated image of the updated page in the update data sub-file in response to the page update request of the data file; Said data file called by means In the page management table so that another user program can refer to and update the updated image of the page updated by the user program in the use end process of the data file and the series of update end processes of the data file. The information of the program table is transferred to the shared table, and when the user program accessing the data file no longer exists, the updated image from the updated data file is written back to the data file, and the data file is written to the user. File update ending means for setting a state in which the update from the program is reflected.

[Action]

In the high-speed file access method of the present invention, a plurality of user programs perform processing while simultaneously accessing the data file, the data file is accessed by the plurality of user programs, the data file is placed in the file device, and the update data file is updated. Consists of a plurality of update data subfiles that store update images in which data file pages are updated by a user program. The update data file is placed on a high-speed file device that can be accessed faster than the file device, and page management The information on the page whose table is updated by the user program and the location information of the update data subfile storing the update image are divided into a program table having a program unit and a shared table which can be used by all user programs. Manage, The file processing means is called by the user program and passes control to the corresponding processing means for starting the use of the data file, inputting / outputting the data file, and terminating the use of the data file, and the file use starting means performs the file processing. The update data subfile is allocated on the high-speed file device corresponding to the user program in the data file use start process called by the means and the position information of the secured update data subfile is registered as a program table in the page management table, and the file is entered. The output means is called by the file processing means, and in response to a request to reference a page of the data file, the page management table is searched to confirm whether or not there is an update image of the page in the update data subfile, and the Update data if update image exists Reads the update image of the relevant page from the sub file at high speed and reads the relevant page from the data file if there is no update image of the relevant page in the update data sub file. The updated table information is reflected in the management table and the updated image of the updated page is stored in the update data subfile. The file update ending means is called by the file processing means, and the data file use ending processing and the series of data file The information of the corresponding program table in the page management table is transferred to the shared table so that the update image of the page updated by the user program in the update end processing can be referred to and updated from other user programs, and the data is updated. File When the user program to be accessed no longer exists, the update image from the update data file is written back to the data file, and the data file is made to reflect the update from the user program.

〔Example〕

Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing a configuration of a high-speed file access method according to one embodiment of the present invention. In the high-speed file access method according to the present embodiment, a plurality of user programs 1 for simultaneously allocating the data file 2 and referring to and updating the data file 2 in units of areas of a fixed size (hereinafter, referred to as pages); A data file 2 that is referenced and updated by the program 1, a file device 3 in which the data file 2 is secured, and a plurality of updates that store an updated image of a page of the data file 2 updated by the user program 1. An update data file 4 composed of a data subfile 4a, a high-speed file device 5 in which the update data file 4 is secured and can be accessed faster than the file device 3, a page number and an update image of a page updated by the user program 1 And the location information of the update data subfile 4a A page management table 6 which is divided into program-specific information and program-sharing information, and a file processing unit which is called by the user program 1 and which passes control to a processing unit corresponding to a processing request for the data file 2 7 and an update data subfile 4a for storing an update image of a page updated in the data file 2 in the use start processing of the data file 2 is secured on the high-speed file device 5, and the location information of the secured update data subfile 4a is stored. A file use start means 8 for registering the information as program-specific information in the page management table 6; Read the update image of the relevant page from the update data subfile 4a at high speed. If the page information of the page is not registered, a process of reading the corresponding page from the data file 2 is performed, and in response to an update request, a file storing the update image of the corresponding page in the update data subfile 4a and reflecting the update image in the page management table 6 The input / output unit 9 and a reference and update of the updated image of the page updated by the user program 1 in the use end processing of the data file 2 or the end processing of a series of updates to the data file 2 from another user program 1. Register the program-specific information on the page management table 6 as program-sharing information that can be referred to by other user programs 1 so that the user program 1 accessing the data file 2 no longer exists. Update image from update data file 4 to data file 2 And a file update ending means 10 to be written into the file.

Referring to FIG. 2, the page management table 6 includes a pointer area 21, a program table area 22, and a shared table area 23.

The pointer area 21 includes a user number 211 indicating the number of user programs 1 using the data file 2 and a program table indicating a program table 221 existing for each user program 1 updating the data file 2. A pointer 212 and a shared table pointer 213 pointing to a shared table 231 existing for each data file 2 are stored.

The user table 1 is stored in the program table area 22.
Data subfile secured on the high-speed file device 5 when the user performs the use start processing of the data file 2
A program consisting of file information 222 having the position information 4a and page information 223 having the page number of the page updated by the user program 1 and the position information in the update data subfile 4a storing the update image. The table 221 is stored.

In the shared table area 23, the image of the program table 221 which is the program-specific information secured in the program table area 22 is transcribed as it is in the end processing of the use of the data file 2 or the end processing of a series of updates. A shared table 231 is stored, which is information on program sharing so that an update image by the program 1 can be referred to and updated by another user program 1.

In the present embodiment, a case where a single data file 2 is accessed from a plurality of user programs 1 is taken as an example, and information for identifying the data file 2 is not provided in the pointer area 21 and the number of data files 2 is one. Only one shared table 231 is reserved for one data file 2.

Referring to FIG. 3, the processing of the file use start means 8 includes an update data subfile securing step 31, a program table creation and update data subfile information registration step 32, a program table point and user number addition step 33. Consists of

Referring to FIG. 4, the processing of the file input / output means 9 includes an update request determination step 41, a program table corresponding page number search step 42, a corresponding page number existence determination step 43, and a shared table corresponding page number search step 44. A corresponding page number presence / absence determination step 45, a corresponding page reading step 46 from a data file, a corresponding page update image reading step 47 from an update data subfile, a shared table corresponding page number searching step 48, a corresponding page number Presence / absence determination step 49, program table pertinent page number search step 4A, pertinent page number presence / absence determination step 4B, and pertinent page update image additional writing step 4C in the update data subfile
And update page information registration step 4D, and step of overwriting the corresponding page update image on the update data subfile
4E.

Referring to FIG. 5, the processing of the file update ending means 10 includes an update data sub-file size reduction step 51,
File information and page information sharing table phase shift step 52, use end notification determination step 53, program table deletion step 54, last user program determination step 55, update image writing step 56 in data file, and sharing It comprises a table end determination step 57, a program table clear step 58, and a step 59 of re-securing the update data subfile and registering file information in the program table.

Next, the operation of the high-speed file access method according to the present embodiment configured as described above will be described.

(1) First, the process of securing the update data subfile 4a by the file use start means 8 and the program table 22
The creation process 1 will be described with reference to FIG.

When the user program 1 notifies the use of the data file 2 through the file processing unit 7, the control is transferred to the file use start unit 8.

The file use start means 8 first stores the update data sub-file 4a on the high-speed file device 5 in a size that can store a predetermined number of pages of the data file 2.
Is secured (step 31).

For example, in FIG. 2, it is assumed that the file use start unit 8 secures the update data subfile 241 based on the use notification of the data file 2 from the user program a (see A in FIG. 2).

Next, the file use start means 8 stores the program table in the program table area 22 of the page management table 6.
221 created and the update data subfile 241 secured earlier
Location information in the high-speed file device 5 by the file information 22
Register as 2 (step 32).

Subsequently, the file use start unit 8 sets the pointer area 21
The program table pointer 212 is searched for a free space, a pointer to the created program table 221 and a program name (program name a in the example of FIG. 2) for identifying the user program 1 are registered, and the number of users 211 is registered. 1
Are added (step 33).

Thus, the processing by the file use start means 8 ends.

Note that, in FIG. 2, the user data b as well as the user data a are updated in the update data sub-file.
It is assumed that 242 has been secured and the program table 221 has been created (see B in FIG. 2).

(2) Next, a process of searching for an update image from the update data file 4 and a process of storing the update image in the update data file 4 by the file input / output means 9 will be described with reference to FIG.

(2-1) First, page information 2 of the program table 221
The process when the page number of the corresponding page is not registered in the page information 233 of the common table 23 and the common table 231 will be described.

When there is a request from the user program 1 for referring to the page of the data file 2 through the file processing means 7, the file input / output means 9 is called.

The file input / output means 9 first determines whether the request is a reference request or an update request (step 41). Since the request is a reference request, the program table 221 indicated by the program table pointer 212 accompanied by the program name of the user program 1
With reference to the page information 223, a search is made as to whether the page number of the page (relevant page) for which the reference request has been made is registered (step 42).

Next, the file input / output means 9 determines whether or not the page number of the corresponding page is registered (step 43). If the page number of the corresponding page is not registered in the page information 223 of the program table 221, the shared table pointer twenty one
By searching the page information 233 of the shared table 231 pointed to by 3, it is searched whether or not the page number of the corresponding page is registered (step 44).

Subsequently, the file input / output means 9 determines whether or not the page number of the corresponding page is registered (step 45). If the page number of the corresponding page is not registered in the page information 233 of the shared table 231 as well, the user Since the program 1 has not updated the corresponding page at all, the corresponding page is read from the data file 2 (step 4).
6).

For example, in FIG. 2, the user program a has a page p2
When the reference request is made, since the page number of the corresponding page p2 is not registered in the page information 223 of the program table 221 and the page information 233 of the shared table 231 at first, the file input / output means 9
Then, the corresponding page p2 is read (see C in FIG. 2).

Next, when there is a request for updating the page referred to from the user program 1 through the file processing means 7, the file input / output means 9 is similarly called.

The file input / output means 9 first determines whether the request is a reference request or an update request (step 41), and since the request is an update request, the shared table 231 indicated by the shared table pointer 213.
With reference to the page information 233, a search is made as to whether the page number of the page (relevant page) requested to be updated is registered (step 48).

Next, the file input / output means 9 determines whether or not the page number of the corresponding page is registered (step 49). If the page number of the corresponding page is not registered in the page information 233 of the shared table 231, an update request is issued. Program table pointer from program name of user program 1
The program table 221 is obtained through 212, and it is searched whether or not the page number of the corresponding page is registered in the page information 223 of the program table 221 (step 4A).

Subsequently, the file input / output means 9 determines whether or not the page number of the corresponding page is registered in the page information 223 of the program table 221 (step 4B). When the number is not registered, it means that the corresponding page has been requested to be updated for the first time, and the updated image of the updated page is additionally written into the update data subfile 4a (step 4C).

Further, the file input / output unit 9 registers in the program table 221 page information 223 including the updated page number of the relevant page and the position information of the update image of the relevant page stored in the update data subfile 4a. (Step 4D).

For example, in FIG. 2, when an update request for the page p2 is made from the user program a, the update image p2 'of the updated page p2 is written in the update data subfile 241 and the page information of the program table 221 is written. The page number p2 and position information are registered in 223 (see D in FIG. 2).

The same applies to user program b.
It is assumed that p15 and page p3 have been updated, and an update image p15 'and page p3' have been written to the update data subfile 242. After that, a series of update ending processing is performed by the file update ending means 10 described later, and the image of the program table 221 pointed to by the program table pointer 212 with the program name b is transcribed to the shared table 231. Is assumed to store the information of the newly secured update data subfile 243 (see E in FIG. 2).

(2-2) Next, page information 2 of the program table 221
The page reference process when the page number of the corresponding page is registered in the page information 233 of the shared table 23 or 23 will be described.

If the page number of the pertinent page is registered in the page information 223 of the program table 221 in the page reference request (step 43), the file input / output means 9 uses the file information 222 and the page information 223 of the program table 221. The update image of the corresponding page is read from the update data subfile 4a (step 47).

For example, in FIG. 2, when the user program a makes a request to refer to the page p2 again, the file input / output means 9 uses the file information 222 and the page information 223 of the program table 221 to update the update data sub-file. The update image p2 'of the corresponding page p2 is read from 241 (step 47).

If the user program a has made a reference request for the page p3, the file input / output means 9 does not register the page number of the page p3 in the page information 223 of the program table 221 (step 43). Then, the page information 233 of the shared table 231 is searched (step 44), and the page number of the corresponding page p3 is registered (step 4).
5) Using the file information 232 and the page information 233 of the shared table 231, read the update image p3 'of the corresponding page p3 from the update data subfile 242 (step 47).

Therefore, the page read and updated by the user program 1 itself and the page read and updated by another user program 1 have the update image stored in the update data subfile 4 a on the high-speed file device 5.
It is possible to read at high speed.

(2-3) Next, the page update process when the page number of the corresponding page is registered in the page information 223 of the program table 221 or the page information 233 of the shared table 231 will be described.

For example, the page referenced earlier from user program a
When there is a request for updating p3, the file input / output means 9
Since the page number of the corresponding page p3 is registered in the page information 233 of the shared table 231 (step 49), the update image p3 ″ of the corresponding page p3 is updated using the file information 232 and the page information 233 of the shared table 231. The update image p3 'of the subfile 242 is overwritten (see F in FIG. 2).

When there is a request to update the page p2, the file input / output means 9 sends the page information 2
Since the page number of the corresponding page p2 is registered in 23 (step 4B), the update image p2 ″ of the corresponding page p2 is updated using the file information 222 and the page information 223 of the program table 221. Overwrite p2 '(see G in FIG. 2).

Therefore, the update image is continuously updated on the high-speed file device 5, and no update to the data file 2 is performed at this time.

Further, since the user program b does not refer to the program table 221 of the other user program a, the page being updated of the user program a, for example, the updated image p2 'of the page p2 is not read. It is possible to refer to and update only the information of the sharing table 231 that is the information of the program sharing, for example, the information of the page p15 and the page p3. Further, since the data file 2 is exclusively controlled on a page basis, a plurality of user programs 1 simultaneously execute the corresponding pages whose page numbers are registered in the page information 223 of the program table 221 or the page information 233 of the shared table 231. Never go to read.

(3) Finally, the process of transferring the page information 223 (233) from the program table 221 to the shared table 231 and the process of updating the data file 2 by the file update ending means 10 will be described with reference to FIG. I do.

When the user program 1 notifies the end of use of the data file 2 or the end of a series of updates through the file processing unit 7, the control is transferred to the file update ending unit 10.

The file update ending means 10 obtains the program table 221 of the notified user program 1 from the program table pointer 212, and based on the file information 222 and the page information 223, updates the data up to the size where the page is actually stored. The size of the sub file 4a is reduced (step 51).

Next, the file update ending means 10 transfers the file information 222 and the page information 223 of the program table 221 to a continuation area of the shared table 231 (Step 52).

Thereby, the file information 232 and the page information 233 of the updated image of the page updated by the user program 1 are moved to the shared table 231 that can be referred to from other user programs 1.
However, the update image can be referred to and updated.

Next, if it is a use end notification of the data file 2, the file update end means 10 deletes the program table 221 from the program table area 22 of the page management table 6, and deletes the program table pointer 21 of the pointer area 21.
2 is erased (step 54).

Further, the file update ending means 10 reduces the number of users 211 of the data file 2 by one, and then, if it is the final user program 1 (determined based on whether the number of users 211 is 0) (step 55). While tracing the shared table 231 from the shared table pointer 213, the updated image of the page updated by the user program 1 using the file information 232 and the page information 233 is written back from the update data file 4 to the data file 2, and the data file is updated. 2 is updated (steps 56 and 57).

If the series of updates of the data file 2 has been notified, the file update ending means 10
221 is cleared (step 58), the update data subfile 4a is re-secured on the high-speed file device 5, and the position information of the update data subfile 4a in the high-speed file device 5 is re-registered as the file information 222 (step 58). Step 5
9).

Therefore, the update to the data file 2 is performed only when the user program 1 using the data file 2 no longer exists. Until then, the page is only updated on the update data file 4 of the high-speed file device 5. Is updated.

Note that, in the above-described embodiment, a case where a page number is used as information for identifying a page has been described as an example. However, the information for identifying a page need not necessarily be a page number.

〔The invention's effect〕

As described above, the present invention holds only an update image of a page of a data file in an update data subfile on a high-speed file device that can be accessed at a high speed, and stores an update image of a page updated by a user program. By making it possible to refer to and update from the updated data subfile on the high-speed file device with consistency from the user program, it is not necessary to put all the data files on the expensive high-speed file device. There is an effect that high-speed access of a data file can be performed while effectively utilizing.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of a high-speed file access method according to an embodiment of the present invention. FIG. 2 is a diagram showing the relationship between the format of a page management table and the update data subfile in FIG. 3 is a flowchart showing the processing of the file use starting means in FIG. 1, FIG. 4 is a flowchart showing the processing of the file input / output means in FIG. 1, and FIG. 5 is the file update ending means in FIG. 6 is a flowchart showing the processing of FIG. In the figure, 1 ... use program, 2 ... data file, 3 ...
File device, 4 ... Update data file, 4a ... Update data subfile, 5 ... High-speed file device, 6 ...
Page management table 7 File processing means 8
File use start means, 9 File input / output means, 10
…… File update ending means, 21 …… Pointer area, 22…
... program table area, 23 ... shared table area,
211: Number of users, 212: Program table pointer, 213: Shared table pointer, 221: Program table, 222, 232: File information, 223, 233: Page information, 231: Shared table, 241, 242, 243: Update data It is a subfile.

Claims (1)

(57) [Claims] In a file access method for a data file which is used by a plurality of user programs and which is exclusively controlled on a page basis and which can be accessed at the same time, a plurality of users who perform processing while simultaneously accessing the data file. A program, the data file accessed by the plurality of user programs, a file device in which the data file is stored, and a plurality of storages for storing an updated image in which a page of the data file is updated by the user program. An update data file comprising an update data sub-file, a high-speed file device in which the update data file is placed and which can be accessed at a higher speed than the file device, and information and an update image of a page updated by the user program. Storing A page management table which separately manages a program table having the location information of the update data subfile in a program unit and a shared table which can be used by all of the user programs, and the data called by the user program. File processing means for transferring control to processing means corresponding to each of processing of starting use of a file, input / output to the data file, and end of use of the data file; and use of the data file which is called by the file processing means. A file use start unit that secures the update data subfile on the high-speed file device in correspondence with a user program in a start process and registers position information of the secured update data subfile as a program table in the page management table; Called by file processing means In response to a request to refer to a page of the data file, the page management table is searched to determine whether or not there is an update image of the corresponding page in the update data subfile. If the update data subfile reads the corresponding page update image at a high speed, if the update data subfile does not include the update image of the corresponding page, the corresponding page is read from the data file, and the page of the data file is updated. File input / output means for reflecting the information of the updated page in the page management table and storing an updated image of the updated page in the update data subfile in response to the request; and Use end processing And information of a corresponding program table in the page management table so that an update image of a page updated by the user program in a process of ending a series of updates of the data file can be referred to and updated by another user program. Is transferred to a shared table, and when the user program accessing the data file no longer exists, the update image from the update data file is written back to the data file to update the data file from the user program. And a file update ending means for setting a state in which the file is reflected.