JPH07182111A - Variable length block storing system for fixed length sector type disk - Google Patents

Abstract

PURPOSE:To improve the capacity efficiency of a variable length block type file and also to improve the access efficiency in an input processing mode in order attain the sequential processing of a fixed length sector type disk. CONSTITUTION:When an output request is received from an input/output requester 9, an input/output control means 10 starts an input/output sector number acquiring means 6 and refers to the block length stored in a buffer 8 to acquire the output sector number. Then the means 10 gives an output request to a disk 11, starts a following access disk address calculating means 7 after the end of output, and acquires the next access disk address to successively carry out the output processings. Meanwhile the means 10 starts the means 6 by an output request given from the requester 9 and refers to the block length stored in the buffer 8 to acquired the input sector number. The means 10 given an input request to the disk 11 as necessary and acquires the next access disk address after the end of input or when no input request is required to successively carry out the input processings.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable length block storage system for a fixed length sector system disk.

[0002]

2. Description of the Related Art Generally, data processed in a user program is often variable in length, and data on a disk is usually variable in length. The unit of data recorded on the disc is called a block, and the variable length data is called a variable length block. The variable length block has the data length of the block at the beginning of the block.

The block size range is defined as the maximum block length in file units at the time of file creation, recorded in a file label on the disk, expanded in the memory table at the start request of the file, and requested at the time of data output. The maximum data length is compared with the maximum data block length on the memory table, and the output of less than the maximum data block length is allowed.

When positioning reference / update is performed on certain data of the data output as described above, the user designates a sequential block number from the beginning of the file according to the number of output data. Since the address designation for the disk is the sector number, the normal block number is converted to the sector number.

This conversion can be easily obtained and converted if the number of sectors per block is constant, but conversion is difficult if the number of sectors per block is not constant, such as in variable-length blocks. Therefore, as shown in FIG. 3, even if the block is enough for one sector, the number of sectors occupied by the maximum block length is secured.

[0006]

As described above, in the variable length block storage method of the conventional fixed length sector type disk, an unused sector occurs, and a file processed by a user program that requires only sequential processing of data. However, there was a problem that the storage efficiency of data deteriorates.

In view of the above problems, it is an object of the present invention to improve the data storage efficiency of a variable-length blocked file intended for sequential processing and also improve the processing efficiency of input processing.

[0008]

SUMMARY OF THE INVENTION A variable length block storage system for a fixed length sector system disk according to the first aspect of the present invention is an input / output of a variable length block file intended for sequential processing on a fixed length sector system disk device. A variable-length block storage system for performing processing, comprising a sector size on the disk, a maximum block size, a start sector number indicating a file position, and an end sector number when a use start request for the variable-length blocked file is made. A file attribute acquisition unit that stores the file attribute information in the file attribute management table and the file attribute acquisition unit are activated, and the start sector number stored in the file attribute management table by the file attribute acquisition unit is recorded in the disk access management table. File use starting means and the variable length blocking file And an input / output control unit configured to input / output a variable-length block having a size of the block at the head of data, the input / output control unit including a plurality of sectors on a fixed sector type disk for input / output. I / O control means is activated, the sector size and maximum block size are obtained from the file attribute management table, and the input / output sector number acquisition means for obtaining the number of input / output sectors; and after the input / output processing by the input / output control means is completed, The address on the disk of the block which is started by the input / output control means and is to be input / output next is obtained from the number of sectors acquired by the input / output control means and the disk address in the disk access management table, It comprises a next access disk address calculation means for updating the disk address.

A variable-length block storage system for a fixed-length sector disk according to the second aspect of the present invention is the variable-length block storage system for a fixed-length sector disk according to the first aspect, wherein the input / output sector number acquisition means is used for input processing. The blocks that are fired and exist in the buffer are of variable length,
When a sector including a part of the next block is present, a buffer reconstructing unit for moving the block to the head of the buffer is included.

[0010]

An embodiment of the present invention will be described in detail below with reference to the drawings.

Referring to FIG. 1, a variable length block storage system for a fixed length sector type disk according to a first embodiment of the present invention uses a file on a fixed sector type disk constituted by variable length blocks to start using a file. Request 1
In response to the file use start request 1 of the file, the file attribute acquisition means 3 for expanding the file attribute information on the disk to the file attribute management table 5 and the file attribute acquisition means 3 are activated to start the file on the disk. File use starting means 2 for acquiring the start sector number indicating the number and recording it in the disk access management table 4.
In response to the input / output request 9 of the file, the input / output of the variable length block having the size of the block at the beginning of the data is input / output in the block composed of a plurality of sectors on the fixed sector type disk for input / output. Output control means 10,
Through this input / output control means 10, the buffer 8 which is an area for reading the data on the disk 11 into the memory or the area for writing the data on the memory to the disk 11 and the input / output control means 10 perform the input / output processing. Of the disk address, the number of input / output sectors, and the buffer address required for the above, the number of input / output sectors is obtained from the block length at the beginning of the block in the buffer 8 and the file attribute management table 5, and After the input / output processing is completed, the input / output control means 10 is activated to start the input / output sector number acquisition means 6 for the address on the disk 11 of the block for the next input / output, and the acquired sector number and the disk access management table 4 are stored. Of the next access data that is obtained from the disk address of It consists disk address calculation unit 7.

Next, regarding the operation of the first embodiment of the present invention, FIG. 1, FIG. 4, FIG. 5, FIG. 6, FIG.
This will be described with reference to FIG.

First, on the fixed sector type disk 11,
For files defined as variable length blocks,
The file use start request process will be described.

When an input / output request is made for the file, the file use start request 1 first calls the file use start means 2.

The file use starting means 2 first calls the file attribute acquisition means 3.

The file attribute acquisition means 3 is a disk 11
The sector size, the maximum block size, the starting sector number indicating the file position, and the ending sector number, which are the file attribute information of the above file, are stored in the file attribute management table 5 from the disk 11.

The file use starting means 2 has the file attribute management table 5 after the processing of the file attribute acquisition means 3 is completed.
The starting sector number is acquired and stored in the disk access management table 4. With the above processing, the file use start request processing is completed.

Next, the processing for making an output request to the file will be described.

In the output request, the data output by the user is stored in the buffer 8 and the input / output request 9 is made (step 5).
1). At this time, the size of the data output by the user is stored at the beginning of the data. The size of this data becomes the block length of the data. The input / output request 9 calls the input / output control means 10 after step 51 is completed.

The input / output control means 10 first acquires the address on the disk 11 to be output from the disk access management table 4 (step 52). Next, the input / output control means 10 calls the input / output sector number acquisition means 6 to obtain the number of sectors, which is the size of the data to be output (step 5).
3).

The input / output sector number acquisition means 6 includes a buffer 8
Block length at the beginning of the data of
3) The sector size is acquired from the file attribute management table 5 (step 84). Input / output sector number acquisition means 6
After step 84 is completed, the number of sectors to be output is obtained from the block length and sector size (step 85). For example, the block length is 1500 bytes and the sector size is 5
If it is 12 bytes, the block length is divided by the sector size, and the value 3 which is an integer multiple of the sector size is the number of output sectors.

The input / output control means 10 determines whether the data to be output this time can be output to the file after the output sector number is obtained by the input / output sector number obtaining means 6 and the end sector of the file obtained from the file attribute management table 5. If there is a free sector that can be output this time, that is, if the number of output sectors obtained in step 85 is less than or equal to the end sector, output processing is executed (step 55). If there is no empty sector, that is, if the number of output sectors is larger than the number of end sectors, the output process is ended. If there is a free sector in step 54 and step 55 and the output process is completed, the next access address calculation means 7 is called to calculate the disk address for the next output (step 56).

The disk address calculation means 7 first acquires the disk address on the disk access management table 4 (step 91) and calls the input / output sector number acquisition means 6 to acquire the sector number (step 92). After the step 92 is completed, the disk address calculation means 7 calculates the next disk address (step 93) and updates the disk address in the disk access management table 4 (step 94).

After the completion of the processing of the disk address calculation means 7, the input / output control means 10 which has calculated the next output address reports the completion of the processing to the input / output request 9, and the input / output request 9 outputs the next data. , The process is repeated.

By the above processing, the block storage image on the disk 11 becomes as shown in FIG. 4, and the output request processing for the file is completed.

Next, the processing for making an input request to the file will be described.

In the input request, the address of the buffer from which the input / output request 9 reads the data is passed to the input / output control means 10 (step 61).

The input / output control means 10 first acquires the disk address from the disk access management table 4 (step 62). Next, the input / output sector number acquisition means 6 is activated to obtain the number of sectors to be input next (step 6).
3).

The input / output sector number acquisition means 6 acquires the block size and sector size from the file attribute management table 5 (step 86) and calculates the number of sectors (step 87). The number of sectors is calculated from the block size defined when the file is created, and is not the size of the block to be read. Therefore, when the size of the block to be read is small, there is a possibility that a part of the next block will be input as shown in the left diagram of FIG.

After the input / output sector number acquisition unit 6 acquires the number of input sectors, the input / output control unit 10 checks so as not to access beyond the area when the file is created. First, in order to calculate the number of remaining sectors of the file, one is added to the end sector number of the file acquired from the file attribute management table 5 from step 62.
The disk address obtained in step 3 is subtracted (step 64).
Next, it is determined whether or not the number of remaining sectors, which is the calculation result of step 64, is 0 or less (step 65), that is, it is determined whether or not there is a remaining sector of the file. Ends the input process. When the input / output control means 10 determines in step 65 that there are remaining sectors in the file, the input / output sector number acquisition means 6 determines the number of input sectors, and step 64.
When the number of input sectors is determined to be larger than the number of remaining sectors, the remaining number of sectors is set as the number of input sectors (step 67). If it is determined in step 66 that the number of input sectors is less than or equal to the number of remaining sectors,
Adopt the number of input sectors. After obtaining the number of input sectors, the input / output control request 10 executes the input processing (step 68), and activates the next access disk address calculating means 7 to obtain the next input address (step 6).
9).

The next access disk address calculation means 7 calculates the next disk address as in the output process and stores it in the disk access management table 4.

After the processing of the next access disk address calculation means 7 is completed, the input / output control means 10 returns the data to the input request 9, the input request is processed, and the input / output control means 10 is activated again. , Data input is repeated.

With the above processing, the input / output processing of the file having no unused sector as shown in FIG. 4 becomes possible,
The input request processing for the file ends.

With the above, the processing of the variable length block storage system for the fixed length sector type disk according to the first embodiment of the present invention is completed.

The variable-length block storage system for a fixed-length sector disk according to the first embodiment of the present invention has a capacity efficiency of variable-length block format files for sequential processing of a fixed-length sector disk and an input processing time. Access efficiency can be improved.

Referring to FIG. 2, a variable length block storage system for a fixed length sector system disk according to a second embodiment of the present invention is the same as the variable length block storage system for a fixed length sector system disk according to the first invention. When a block existing in the buffer 8 is activated by the input / output sector number acquisition means 6 and has a variable length and a sector including a part of the next block exists, the block is moved to the head of the buffer 8. A buffer reconstructing means 12 is included.

Next, the operation of the second embodiment of the present invention will be described with reference to FIGS. 2, 7, 10, and 11.

In the input request, the address of the buffer from which the input / output request 9 reads the data is passed to the input / output control means 10 (step 71).

The input / output control means 10 first acquires the disk address from the disk access management table 4 (step 72). The input / output sector number acquisition means 6 is activated to obtain the number of sectors to be input next (step 7).
3).

The input / output sector number acquisition means 6 acquires the block length and sector size from the file attribute management table 5 (step 106) and calculates the number of sectors (step 107). The number of sectors is calculated from the block size defined when the file is created, and is not the size of the block to be read. Therefore, when the size of the block to be read is small, there is a possibility that a part of the next block will be input as shown in the left diagram of FIG. Such input is only input processing immediately after the request to start using the file.If data already exists in the buffer, it is checked if the block to be input next exists as a complete block in the buffer and it exists. If so, the following method is used to control not to execute I / O.

The input / output sector acquisition means 6 first stores the number of effective sectors of the disk access management table 4 in the temporary memory as the number of remaining sectors in the buffer (step 1).
09). Next, the block length of the input block at the head of the buffer is acquired (step 10A), and the number of sectors included in the block length is obtained (step 10B). Next, from the number of remaining sectors obtained in step 109, step 10
The number of sectors obtained in B is subtracted (step 10C), and it is determined whether the calculation result of step 10C is larger than 0, that is, whether the next input block exists in the buffer 11 (step 10D). When it is determined in step 10D that the calculation result of step 10C is 0 or less, that is, the block to be input next does not exist in the buffer 11 as a complete block, the block size on the file attribute management table 5 is determined as the number of input sectors. And the number of sectors obtained from the sector size is returned (step 10E). Further, the number of effective sectors in the disk access management table 4 is also set (step 1).
0K).

The input / output sector acquisition means 6 performs step 10
When it is determined in step D that the calculation result of step 10C is greater than 0, that is, the next input block exists in the buffer 11 as a complete block, the calculation result of step 10C is first set as the number of remaining sectors (step 10G). The buffer reconfiguration means 12 is called (step 10H), the block to be input this time is moved so as to start from the head of the buffer as shown in FIG. 11, and the number of valid sectors of the disk access management table 4 is changed (step 10I). . The input / output sector acquisition means 6 returns to step 10A after the end of step 10I, determines again whether or not the block moved to the head of the buffer is complete,
When it is determined that the number of input sectors is complete, the number of input sectors is set to 0 and returned (step 10J). If it is determined to be incomplete, as described above, the number of sectors obtained from the block size and the sector size on the file attribute management table 5 is returned as the number of input sectors (step 10E). Also in the number of effective sectors,
The number of sectors is set (step 10K).

Input / output control means 1 which has acquired the number of input sectors
For 0, it is determined whether the number of input sectors is 0, and when it is determined that the number of input sectors is 0, the next access disk address calculation means 7 is called, the next disk address is obtained, and the processing is completed. The input / output request which has received the completion notification of the input / output control means 10 processes the data and repeats the processing of calling the input / output control means 10.

When it is determined that the number of input sectors is not 0, it is checked that the file is not accessed beyond the area at the time of creation (steps 74, 75, 7).
6). First, in order to calculate the number of remaining sectors of the file, the disk address acquired from the disk access management table 4 is subtracted from the end sector number of the file acquired from the file attribute management table 5 plus one (step 74). ). Next, it is determined whether the number of remaining sectors, which is the calculation result of step 74, is 0 or less (step 7
5), that is, determining whether there are any remaining sectors of the file, and if there are no more remaining sectors,
Input processing ends. The input / output control means 10 is step 7
If it is determined in step 5 that there are remaining sectors in the file, the number of input sectors obtained by the input / output sector number acquisition means 6 is compared with the calculation result of step 74, that is, the number of remaining sectors in the file (step 76), and the input When it is determined that the number of sectors is larger than the number of remaining sectors, the number of remaining sectors is set as the number of input sectors (step 77). If it is determined in step 76 that the number of input sectors is less than or equal to the number of remaining sectors, the number of input sectors is used as it is. After obtaining the number of input sectors, the input / output control request 10 executes the input processing (step 78), and activates the next access disk address calculating means 7 to obtain the next input address (step 79).

The next access disk address calculation means 7 calculates the next disk address in the same way as the output processing, and stores it in the disk access management table 4.

After the processing of the next access disk address calculation means 7 is completed, the input / output control means 10 returns the data to the input request 9, the input request is processed, and the input / output control means 10 is activated again. , Data input is repeated.

As described above, the input request processing for the file which is the variable length block storage system of the fixed length sector system disk according to the second embodiment of the present invention is completed.

The variable length block storage system for a fixed length sector type disk according to the second embodiment of the present invention has a small block length, and when there are n blocks of data in the buffer, useless input / output operations are performed. Since it is not performed, there is an effect that access efficiency can be improved.

[0049]

As described above, the variable length block storage system for a fixed length sector type disk according to the present invention inputs the capacity efficiency and the input of a variable length block format file for sequential processing of a fixed length sector type disk. It is possible to improve access efficiency during processing.

[Brief description of drawings]

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

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

FIG. 3 is a diagram showing a block storage format of a variable-length block format file created on a conventional fixed sector disk in the first and second embodiments of the present invention.

FIG. 4 is a block diagram showing a block storage format of a variable length block format file created on a fixed sector system disk in the first and second embodiments of the present invention.

FIG. 5 is a flowchart showing the processing of the input / output request 9 and the input / output control means 10 in the first embodiment of the present invention.

FIG. 6 is a flow chart showing the processing of the input / output request 9 and the input / output control means 10 in the first embodiment of the present invention.

FIG. 7 is a flowchart showing the processing of the input / output request 9 and the input / output control means 10 in the second embodiment of the present invention.

FIG. 8 is a flow chart of the input / output sector number acquisition means 6 in the first exemplary embodiment of the present invention.

FIG. 9 is a flow chart of the disk address calculation means 7 in the first embodiment of the present invention.

FIG. 10 is a flow chart of the input / output sector number acquisition means 6 in the second exemplary embodiment of the present invention.

FIG. 11 is a diagram showing a process of a buffer reconfiguring unit 12 in the second exemplary embodiment of the present invention.

[Explanation of symbols]

 1 File Use Start Request 2 File Use Start Means 3 File Attribute Acquisition Means 4 Disk Access Management Table 5 File Attribute Management Table 6 I / O Sector Count Acquisition Means 7th Access Disk Address Calculation Means 8 Buffer 9 I / O Requests 10 I / O Control Means 11 disk 12 buffer reconstructing means

Claims (2)

[Claims] 1. A variable-length block storage system for performing input / output processing of a variable-length blocked file for sequential processing on a fixed-length sector disk device, the request to start using the variable-length blocked file. And a file attribute acquisition unit for storing file attribute information having a sector size, maximum block size, a start sector number indicating a file position, and an end sector number on the disk in a file attribute management table. And a file use starting means for recording the start sector number stored in the file attribute management table by the file attribute acquisition means in the disk access management table, and input / output at the time of input / output request of the variable-length blocked file. Perform multiple sectors on a fixed sector disk. Input / output control means for inputting / outputting a variable-length block having the size of the block at the beginning of the data, and the sector size and maximum block size obtained from the file attribute management table by the input / output control means. The input / output sector number obtaining means for obtaining the number of input / output sectors and the address on the disk of the block to be input / output next, which is started by the input / output control means after the input / output control means completes the input / output processing. A fixed-length sector, which comprises: a next access disk address calculation means for updating the disk address in the disk access management table by obtaining it from the number of sectors acquired by the input / output control means and the disk address in the disk access management table. System variable length block storage system. 2. When the block which is started by the input / output sector number obtaining means at the time of input processing and has a variable length in the buffer and a sector including a part of the next block exists, the block is set to the head of the buffer. 2. A variable length block storage system for a fixed length sector type disk according to claim 1, further comprising buffer reconfiguring means for moving to a disk.