JP2001265628A - File recording management system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a file recording management system capable of recording file data by efficiently using a storage area. SOLUTION: A data area 150 is divided into plural basic blocks 200 provided with a prescribed fixed size and the respective basic blocks 200 are subdivided into a small block 1-the small block n. In addition to a file allocation table for indicating a linking condition among the basic blocks, small block allocation information for indicating the using condition of the respective small blocks inside the basic block is provided further and the files of various sizes are divided and recorded in the basic blocks and the small blocks.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a file recording management system and a file recording management method, and more particularly to a file recording management system for recording a file in a storage area conforming to a FAT (File Allocation Table) type format.

[0002]

2. Description of the Related Art Inside a device such as a computer, a storage area for recording a program file, a data file, and the like (hereinafter, these are also simply referred to as files) is provided.

FIG. 9 is a conceptual diagram showing the configuration of the storage area 100. Referring to FIG. 9, storage area 100 has a system area 110 and a data area 150. The system area 110 includes a file directory for indicating information of a file to be recorded, and a file allocation table FAT which is a file allocation table for correctly connecting file data divided into storage blocks and stored.

[0004] The file directory contains a file name,
Information such as a recording time / date and a head block number for designating a block in which a head part of the file data is recorded is held. The file allocation table (hereinafter, also simply referred to as FAT) holds information for correctly linking blocks used to record the same file.

[0005] The data area 150 records data constituting a file (hereinafter, also simply referred to as file data).

FIG. 10 is a conceptual diagram showing the structure of the data area 150. Referring to FIG. 10, data area 150
Is divided into a plurality of basic blocks 200 having a predetermined fixed data size. Each of the basic blocks 200
For example, it has a fixed data size of 512 bytes to 32 Kbytes. Since the basic block length, which is the data size of the basic block, is determined by hardware at the time of initial setting of the media apparatus, it cannot be generally changed. Basic blocks are also called clusters, and file data recording is performed for each basic block. These basic blocks are
It is managed according to the FAT type format.

FIG. 11 is a conceptual diagram for explaining recording management of file data using a file allocation table.

Referring to FIG. 11, the data area is divided into a plurality of M-byte allocation blocks. In the example of FIG. 11, one file is formed by the divided file data (A) to (F). In other words, the file data forming one file is divided into (A) to (F) and recorded in the allocation block. Each allocation block is assigned a block number. In FIG. 7, these block numbers are represented by decimal numbers.

The divided file data (A) to (F)
Is recorded in the file allocation table FAT. The FAT item number is
The FAT item value is associated with the block number indicating the allocation block, and the FAT item value records the FAT item number (decimal notation) corresponding to the allocation block to be referred next to correctly link the file data. ing.

First, when it is specified by the file directory that the first block number is 15, the FAT
The FAT item value of the item number “15” is referred to. Since “10” is recorded here, the FAT item value of the FAT item number “10” is referred next. Thus, F
By sequentially referring to the FAT item numbers recorded as the AT item values, the correct link order of the allocation blocks is specified. In the allocation block where the end of the file is recorded, “EOF” is recorded in the corresponding FAT item value.

In the example of FIG. 7, the allocation block "15" specified by the file directory
, The allocation blocks are linked in the order of 15 → 10 → 18 → 19 → 24 → 25, and finally file data (A) to (A) indicating the contents of the actual file.
(F) is obtained.

As described above, as the FAT item value, numerical data indicating the allocation block to be referred next or “EOF” indicating that the end of the file is recorded is entered. In practice, a plurality of bits of data for indicating such information as digital data are recorded.

As other codes, "empty (unrecorded)", "defective", "use prohibited", and the like are defined as different codes, and these are recorded as FAT item values to manage the allocation block. Can do it. That is, the numerical data corresponding to the next block number and the allocation block corresponding to the FAT area in which the code corresponding to the EOF is written cannot be used for writing new data. It is grasped by things.

FIG. 12 is a diagram conceptually illustrating the recorded contents of the file allocation table. Referring to FIG. 12, the file allocation table is divided into a plurality of areas for storing data corresponding to FAT item numbers. FIG. 8 shows data corresponding to FIG. 11 as an example. For example, the region F-15
Is an area for recording the FAT item corresponding to the FAT item number 15, and the area F-25 is an area for recording the FAT item corresponding to the FAT item number 25. Therefore, as shown in FIG. 7, data corresponding to the next block number 10 and the code EOF indicating that the end of the file is recorded are recorded in the areas F-15 and F-25, respectively.

In the following, the data recorded in the FAT will be described in a notation method according to FIG.

According to such a FAT format, a file can be divided into a plurality of allocation blocks and recorded.

[0017]

When a file having a capacity equal to or larger than the basic block length is recorded in the data area 150, file data is stored over a plurality of basic blocks. When recording data having a large storage capacity such as video and audio over such a plurality of basic blocks, if the data is discretely recorded in physically discontinuous areas in the storage medium, these data are When reading data in real-time processing, access cannot be performed smoothly depending on the moving time of the drive head, and there is a possibility that continuous data processing becomes difficult.

Therefore, in consideration of recording such a large amount of data processed in real time, it is desirable to increase the capacity of the basic block and give priority to recording in a physically continuous area.

On the other hand, the data capacity of a file varies depending on the type of the file, and there is a file having a very small data capacity such as a very small document file.

However, in the current file recording management system, recording of file data is executed in basic block units, so that two or more file data cannot be recorded in one basic block. Therefore, if the fixed length of the basic block is set too large, the actual data is not recorded in each basic block, but the area in which data of another file cannot be recorded increases, and the storage is increased. There is a problem that the use efficiency of the area is significantly reduced.

On the other hand, if the fixed length of the basic block is made too small, the number of basic blocks linked when recording a large amount of data becomes very large, and the access performance when reading such data is reduced. There is concern about the decline.

Further, if recording and erasing of data is repeated due to frequent input / output of data, it becomes difficult to secure a physically continuous free area, and so-called fragmentation (fragmentation) occurs. There are points.

The present invention has been made to solve such a problem, and an object of the present invention is to provide a file recording method capable of recording file data by efficiently using a storage area. To provide a management system.

[0024]

According to the present invention, there is provided a file recording management system for recording a file in a storage area divided into a plurality of blocks having a predetermined same capacity. Dividing means for dividing into small blocks, designating means for designating at least one block and a small block for recording a file according to the data capacity of a file to be recorded, blocks and small blocks on which the file is recorded And a file allocation unit for associating the file with the file.

Preferably, when the data capacity is equal to or smaller than the predetermined same capacity, the designating means designates one of the plurality of blocks and handles one of the blocks designated according to the data capacity. When at least one of a plurality of small blocks to be processed is specified and the data capacity is larger than a predetermined same capacity, N blocks (N: a natural number of 2 or more) of the plurality of blocks according to the data capacity are specified. , And at least one of a plurality of small blocks corresponding to the N-th block in which the end portion of the file to be recorded among the designated N blocks is recorded.

Preferably, when the file data constituting the file to be recorded has temporal continuity, the specifying means specifies physically continuous blocks and small blocks.

Preferably, when the file data constituting the file to be recorded is temporally non-contiguous, the designating means preferentially designates a fragmentary block and a small block. 1. The file record management system according to 1.

Preferably, the defragmenter is started in response to an instruction and rearranges the recorded area and unused area of blocks and small blocks in the storage area to increase the number of physically continuous unused areas. Means are further provided.

More preferably, at the time of activation of the defragmenting means, before executing the relocation, the dividing means reduces the capacity of each of the plurality of small blocks according to the data capacity of the file recorded in the storage area. Reset.

Preferably, the capacity of each of the plurality of small blocks is different from the capacity of at least one other of the plurality of small blocks.

More preferably, the capacity of each of the plurality of small blocks is (1/2) where D is a predetermined same capacity.
It is represented by ^K · D (K: natural number).

Preferably, each of the plurality of small blocks has the same capacity.

[0033]

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

FIG. 1 is a conceptual diagram illustrating the configuration of a data area of a storage area constituting a data recording management system according to the present invention.

Referring to FIG. 1, data area 150 in the storage area is divided into a plurality of basic blocks 200. As described above, each of the basic blocks 200 has the same fixed size. In the present invention, each of the basic blocks 200 is further subdivided into n (n: a natural number of 2 or more) small blocks 1 to n. The data capacities of the small blocks 1 to n can be set arbitrarily, and the data capacities of the small blocks can be equal or different.

For example, if the data size of the basic block 200 is 64 Kbytes, it is also possible to divide this basic block into four small blocks 1 to 4 each having 16 Kbytes, which is 32 Kbytes. , 16K bytes, 8K bytes, 4K bytes, and 4K bytes. As described above, if the data size of each small block is D · (1/2) ^K (K: natural number) with respect to the basic block length D, the basic block can be efficiently divided.

Hereinafter, in the embodiment of the present invention, as an example, a configuration in which one basic block 200 is divided into four small blocks 1 to 4 having different data capacities will be described. The data capacity of each of the small blocks is assumed to be larger in the order of small block 1> small block 2> small block 3> small block 4.

The file recording management system according to the present invention aims at improving the use efficiency of a storage area by recording file data by a combination of basic blocks and small blocks formed by dividing the basic blocks.

Further, a file handling a large amount of real-time data, reflecting the real-time property of file data, ie, the presence or absence of temporal continuity, is recorded over physically continuous basic blocks, and conversely, By recording small-capacity files such as data in units of small blocks, the use efficiency of the storage area is further improved.

In the file record management system of the present invention, in addition to the file allocation table FAT, small block allocation information for indicating the use status of these small blocks is further provided.

In this case, the original file allocation table indicates a link between basic blocks when a file is arranged over a plurality of blocks, and the small block allocation information indicates each small block in the basic block. Indicates the usage status of.

FIG. 2 is a diagram showing the structure of a file directory according to the file record management system of the present invention.

Referring to FIG. 2, entry points and end points are shown in the file directory corresponding to the file names. The entry point and the end point require information up to a small block unit.

If the file data can be recorded only in one basic block, the entry point indicates all the small blocks to be recorded. For example, when the file A can be recorded only with the small blocks 3 and 4 of the basic block 9, the entry points are as follows.
A basic block 9 and small blocks 3 and 4 are recorded. The basic block 9 and the small block 4 are recorded at the end point where the end of the file data is recorded, that is, at the end point indicating the block corresponding to “EOF”.

File B is a file that can be recorded with only one small block. In this case, the same small block is recorded at the entry point and the end point. In the example of FIG. 2, the basic block 9 and the small block 1 are recorded at the entry point and the end point, respectively.

On the other hand, for a large-capacity file recorded over a plurality of basic blocks, the basic block in which the leading end of the file data is recorded is specified, and the small block in the entry point is set to "0". I do. This indicates that the file C is recorded over a plurality of basic blocks. For the end point, see "E
A small block corresponding to OF "is designated.

FIG. 3 is a diagram showing a file allocation table and small block allocation information corresponding to the recording status of files A to C shown in FIG.

As described with reference to FIG. 2, the file C is a large-capacity file, and is recorded using the entire basic blocks 3 to 7 and the small blocks 1 and 2 in the basic block 8. In response, "4" indicating the next basic file is recorded in the area F-3 corresponding to the third FAT item value specified by the entry point,
FAT item values are recorded in each of the areas F4 to F7 so as to be sequentially linked to the basic blocks 5 → 6 → 7 → 8.

An "EOF" code is written in the area F-8 to indicate that the end of the file C is stored. Correspondingly, the small block allocation information is stored in the area F corresponding to the basic blocks 3 to 7.
In 3 to F7, all bits are designated as "1" because all small blocks are used.

The small block allocation information is
Each area is indicated by 4-bit data, and each bit corresponds to the usage status of the small blocks 4, 3, 2, and 1 from the left, and "1" indicates that data has been recorded in the corresponding small block. And "0" indicates that the corresponding small block is a free area (unused).

The file B is recorded only in the small block 1 in the basic block 9, and the file A is recorded in the basic block 9
It is described in small blocks 3 and 4 in the middle. That is, for the basic block 9, only these two small-capacity files are recorded, and there is no need to link to other basic files. Therefore, the "EOF" code is written in the area F-9 corresponding to the basic file 9.

In each bit of the small block allocation information corresponding to the basic block 9, a plurality of bits "1101" indicating the use of the small blocks 1, 3 and 4 and the non-use of the small block 2 are written. .

The small block allocation information is stored in each area in the file allocation table.
The number of bits of the T item value may be extended, and the extended bits may represent the above-described multiple-bit data.

In this way, it is possible to divide files of various sizes into basic blocks and small blocks and record them using the file allocation table and the small block allocation information.

FIGS. 4, 5, 6 and 7 are first, second, third and fourth flowcharts showing a file recording method according to the file recording management system of the present invention.

Referring to FIG. 4, when file recording is started (step S100), first, the data size of a file to be recorded is obtained (step S1).
10). Next, it is determined whether or not the data size is clear (step S120). If the data size is determined, the magnitude between the data size and the basic block length is determined (step S130). The data size is
If the length is smaller than the basic block length, the file to be recorded is recorded in one basic block, and therefore the step group S200 is executed.

Referring to FIG. 5, in this case, the attributes of the file data are continuously checked to determine whether there is temporal continuity (step S210). As a result,
If the data does not have continuous time, priority is given to maximizing the use efficiency of the storage area, and one or more small blocks are combined to select the optimal space and record the file data. Is performed (step S220). Thus, the file recording process ends (step S5).
00).

On the other hand, if the file data has temporal continuity, it is desirable to record these file data in small blocks in a continuous area. Therefore,
In this case as well, one or a plurality of small blocks are selected according to the data size. At this time, data is always recorded in order from the first small block, that is, the small block 1 in the basic block (step S230). ). When the data is recorded, the file recording process ends (Step S500).

Referring to FIG. 4 again, if the data size of the file is unknown or the data size of the file is known but is larger than the basic block length, the data should be recorded in a plurality of basic blocks. The processing is advanced on the assumption that In this case, first, the attribute of the file data is checked to determine whether there is temporal continuity (step S140). As a result, if the file data has temporal continuity, the step group S
300 is executed.

Referring to FIG. 6, in this case, first, the number L (L: a natural number of 2 or more) of basic blocks required for recording a file is obtained from the data size of the file. Based on this, L consecutive free basic blocks are selected and secured (step S3).
10). File data is sequentially stored in the secured L basic blocks (steps S330 and S340), and until the data is stored in the final L-th basic block.
This process is repeatedly executed.

When data is stored in the L-th basic block, one or more small blocks are selected in the L-th basic block according to the remaining data size. However, at this time, in consideration of the temporal continuity of the file data, data is always recorded from the first small block (step S350). Thus, the file recording ends (step S50).
0).

Referring again to FIG. 4, in step S140, it is necessary to record in a plurality of basic blocks.
When it is determined that there is no temporal continuity in the file data, a step group S400 is executed. Referring to FIG. 7, in this case, first, from the data size of the file,
The number L (L: a natural number of 2 or more) of basic blocks required to record this file is obtained (step S).
410). When step group S400 is executed,
Since there is no need to record file data in a continuous area, it is not necessary to continuously secure L free basic blocks only in optimizing the use efficiency of the storage area. When such file data is recorded, the continuity of the remaining free basic blocks can be improved by preferentially securing basic blocks that have been fragmented due to past data recording / erasing. (Step S42
0).

As described above, file data is sequentially recorded in the L basic blocks (steps S330 and S34).
0) This process is repeated until data is recorded in the last L-th basic block.

When file data is recorded in the L-th basic block, which is the last block of the L basic blocks, one or a plurality of small blocks are stored in accordance with the remaining data size. The combination and the optimal space are selected and the remaining file data is recorded (step S450). At this time, it is not necessary to continuously secure these small blocks. Thus, the file recording ends (step S500).

According to the method described above, it is possible to appropriately select basic blocks and small blocks according to the data size of a file to be recorded and the temporal continuity of the file data, and record the file data. It is possible.

FIG. 8 is a flowchart showing a file reading method in the data management recording system of the present invention.

Referring to FIG. 8, when reading of a file is started (step S600), first, as described with reference to FIG. 2, a file block is referred to and a start block is determined from an entry point (step S600). S61
0). Next, F of the basic block corresponding to the start block
The AT item value is referred to (Step S620). FAT
If the item value is "EOF" (step S63)
0) Since the file to be read is recorded only in the small block in the start block, the data recorded in the corresponding small block is referred to by referring to the information on the small block at the entry point and the end point in the file directory. Are sequentially read to form a file (step S660). As a result, a file having a data size smaller than the basic block length can be read (step S700).

On the other hand, if the FAT item value corresponding to the start block is not “EOF” and data specifying the next file allocation table is entered (step S630), the basic operation is performed by following the file allocation table. The link of the block can be grasped (step S640). Furthermore, by referring to the information on the small blocks at the entry point and the end point of the file directory, the appropriate small block in the basic block in which the end of the file data is recorded is designated and divided and recorded. The data can be linked to form a file (step S650). As a result, a file having a data size larger than the basic block length can be read (step S700).

As described above, it is possible to read out various files that are divided into basic blocks and small blocks and recorded according to the data size.

The data capacity of the small block is determined as follows.
When initializing the media device in consideration of the average value, maximum value, etc. of the data size of the file handled by the system,
What is necessary is just to define the division including the size of the basic block and the small block in the corresponding storage area.

In general, as a measure for improving the use efficiency of a storage area, a defragmentation method for rearranging a block in which data is recorded in order to combine a used area and an unused area in the storage area into continuous areas, respectively. A measure is executed, and at this time, a configuration may be adopted in which the size of the small block is reset according to the average value or the maximum value of the data size of the recorded file.

If the defragmentation process is automatically started each time a small-capacity file that easily causes fragmentation is recorded, the efficiency of the storage area can be further improved.

The embodiments disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

[0074]

According to the file recording management system of the present invention, it is possible to perform recording according to the data capacity of a file to be recorded by using a small block obtained by further dividing a block having a predetermined same capacity. Therefore, fragmentation in the storage area can be suppressed, and the use efficiency of the storage area can be improved.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram illustrating a configuration of a data area of a storage area configuring a data recording management system according to the present invention.

FIG. 2 is a diagram showing a configuration of a file directory according to the file record management system of the present invention.

FIG. 3 is a diagram showing a file allocation table and small block allocation information corresponding to recording states of files A to C shown in FIG. 2;

FIG. 4 is a first flowchart showing a file recording method according to the file recording management system of the present invention.

FIG. 5 is a second flowchart showing a file recording method according to the file recording management system of the present invention.

FIG. 6 is a third flowchart showing a file recording method according to the file recording management system of the present invention.

FIG. 7 is a fourth flowchart showing a file recording method according to the file recording management system of the present invention.

FIG. 8 is a flowchart showing a file reading method in the data management recording system of the present invention.

9 is a conceptual diagram showing a configuration of a storage area 100. FIG.

FIG. 10 is a conceptual diagram showing a configuration of a data area 150.

FIG. 11 is a conceptual diagram illustrating recording management of file data using a file allocation table.

FIG. 12 is a diagram conceptually illustrating the recorded contents of a file allocation table.

[Explanation of symbols]

100 storage area, 110 system area, 150 data area, 200 basic blocks, FAT file allocation table.

Claims (9)

[Claims] 1. A file recording management system for recording a file in a storage area divided into a plurality of blocks having a predetermined same capacity, comprising: dividing means for dividing each block into a plurality of small blocks at an initial setting; Specifying means for specifying at least one of the block and the small block for recording the file in accordance with the data capacity of the file to be recorded; and the block and the small block in which the file is recorded; A file recording management system, comprising: file allocation means for associating the file with the file. 2. When the data capacity is equal to or less than the predetermined same capacity, the designating means designates one of the plurality of blocks and the one designated according to the data capacity. If at least one of the plurality of small blocks corresponding to one block is specified and the data capacity is larger than the predetermined same capacity, N of the plurality of blocks is determined according to the data capacity. (N: a natural number of 2 or more), and the plurality of small blocks corresponding to the N-th block in which the end portion of the file to be recorded among the designated N blocks is recorded. At least one of them
2. The file record management system according to claim 1, wherein one of the files is designated. 3. The method according to claim 1, wherein the specifying unit specifies the physically continuous block and the small block when file data constituting the file to be recorded has temporal continuity. A file record management system as described. 4. When the file data constituting the file to be recorded is non-consecutive in time, the designating means preferentially designates the fragmentary block and the small block. The file record management system according to claim 1, wherein: 5. The apparatus is activated in response to an instruction and rearranges a recorded area and an unused area of the block and the small block in the storage area to increase the physically continuous unused area. 2. The file recording management system according to claim 1, further comprising: 6. The method according to claim 1, wherein when the defragmentation unit is activated, the division unit executes each of the plurality of small blocks according to a data capacity of a file recorded in the storage area before executing the relocation. 6. The file record management system according to claim 5, wherein the capacity of the file is reset. 7. The capacity of each of the plurality of small blocks is:
2. The file record management system according to claim 1, wherein the capacity of the file recording management system differs from at least one of the plurality of small blocks. 8. The capacity of each of the plurality of small blocks is:
Assuming that the predetermined same capacity is D, (１ ／) ^K · D
The file record management system according to claim 7, wherein the file record management system is represented by (K: natural number). 9. The file record management system according to claim 1, wherein each of the plurality of small blocks has the same capacity.