JPH01158547A - Buffer control system for data file device - Google Patents

Abstract

PURPOSE:To improve an access efficiency on reading by maintaining a physical continuity in a data buffer and storing data to have a mutual relation or to be consecutive. CONSTITUTION:A pit map part 7 is split into unit pit rows a1-am which plural continuous pits are made into one group, and new data are stored in a buffer area 6 corresponding to the top pit of the unit pit rows of which all pits are '0'. Beside, the data which have a mutual relation are stored in buffer areas B1-Bn corresponding to the pits of the same unit pit rows a1-am. Thus, a detecting time is reduced comparing to a usual system to detect the pit map part 7 for every one pit. Besides, since the storage of the data to the buffer area is practiced physically consecutive continuous area, for the reading of the data, reading is practiced continuously and the excessive detecting time is not needed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a buffer management method when data processed by a data processing device is stored in a file device having a data buffer.

[Conventional technology]

As a data buffer management method for storing data such as telegrams in a file device having a data buffer, a bitmap method is known, for example, as disclosed in Japanese Patent Publication No. 61-26684.

This bitmap method has a bitmap section that indicates whether or not data has already been stored in each buffer area obtained by dividing the data buffer into a predetermined amount of data. In the case of , data is already stored in the buffer area corresponding to that bit, and in the case of "0" (off), data is not stored.

When storing data in the data buffer, the bitmap section is searched to detect a "0" bit, and after storing the data in the corresponding buffer area, the bit is rewritten and updated to "1". .

[Problem that the invention seeks to solve]

In this case, the general method of searching for the "0" bit is to search sequentially from the first bit of the bitmap section. Therefore, the search time differs depending on the position of the "0" bit, and there is a problem in that the search time becomes extremely long, especially when the "0" bit is located near the final pit of the bitmap section.

Furthermore, when storing data that has some kind of relationship with each other in a - group, there is a high possibility that these data groups will be stored in a diffused manner within the data buffer. Therefore, when reading these - group data successively, time is required to search between the respective buffer areas to read the next buffer area.

The present invention has been made in view of the above-mentioned circumstances, and is intended to shorten the time required to detect a "0" bit when searching a bitmap section, and also to reduce the time required to detect a "0" bit when searching a bitmap section, and to The present invention aims to provide a buffer management method for a data file device that improves access efficiency when reading data by maintaining physical continuity in the data buffer.

Means for Solving Problem C] In the buffer management method of the data file device of the present invention,
Divide the bitmap part into unit bit strings that are a set of multiple consecutive bits, store new data in the buffer area corresponding to the first bit of the unit bit string where all bits are 0'', and have mutual relationships. Data is stored in buffer areas corresponding to bits of the same unit bit string.

The present invention provides a data buffer divided into a plurality of unit blocks, a bitmap section that indicates whether data is stored in each unit block by turning each bit on or off, and each bit of the bitmap section. In a buffer management method of a data file device, the data file device is equipped with a bit detection unit that searches for on/off of a bit and detects an off bit, and stores data in a unit program of a data buffer corresponding to an off bit. , when the bits in the bitmap section are divided into a plurality of unit bit strings, each consisting of a predetermined number of bits, and new data to be stored is given, the bit detection section detects that all bits are off. Store the data in the unit block of the data buffer corresponding to the first bit of the unit bit string, turn on and 7) of the bitmap section corresponding to the unit block in which the data is stored, and confirm that the data to be stored is already data. If there is continuity with the data stored in the buffer, detect the off-pit in the unit bit string that includes the bit corresponding to the final unit block in which the already stored data is stored, and generate the corresponding unit. Store the data in a block,
The method is characterized in that bits corresponding to a unit block in which data is stored are turned on, and when all of the unit bit strings are on, a new unit bit string in which all bits are off is detected and data is stored.

[Operation] In the buffer management method of the data file device of the present invention,
Interrelated or consecutive data are stored in physically consecutive buffer areas of the data buffer.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in detail with reference to the drawings showing embodiments thereof.

FIG. 1 is a block diagram showing the configuration of a data file device to which the buffer management method according to the present invention is applied.

In the figure, 1 is a data processing device, and 2 is its data processing section.

Further, the data processed by this data processing device 1 is temporarily stored in the memory 3, but if necessary, it can be stored in the file device 4.
It is also stored in

The file device 4 includes a buffer area 6 and a bitmap section 7.
and a bit detection section 5. Further, the bit detection section 5 includes an address counter 8, a unit bit string register 9, a unit block number register 10, and the like.

The buffer area 6 is divided into unit blocks 81 to Bn each having a fixed data length.

Further, the bit map section 7 is composed of the same number of bits b1 to bn as the number of unit blocks 81 to Bn of the buffer area 6, and each bit b1 to bn corresponds to each unit block 81 to an of the buffer area 6. are doing. If the value of each bit b1 to bn is "1' (ON), it means that data is already stored in the corresponding unit block, and if it is 0" (OFF), no data is stored. It is shown that.

Furthermore, each bit b1 to bn of this bitmap section 7 is
For example, in this embodiment, the unit bit string a1 consists of bits b1 to b4, and the unit bit string a2 consists of bits b5 to b5.
b8, the unit bit string al”am(m=
n/4).

The address counter 8 receives the unit bit strings a1 to aIl! of the bitmap section 7. The values of are written sequentially.

The unit bit string register 9 is a read/write register into which 4-bit values forming each unit bit string ALXAM written by the address counter 8 are written.

The unit block number register 10 also contains the unit block number B1 of the buffer area 6 into which data is to be written next.
=Bn is written.

Now, in such a data file device, when data is received by the data processing device 1, the processing section 2 processes the data and temporarily stores it in the memory 3. Here, if the data length of the data received by the data processing device l is the data length of 0.7 unit blocks of the buffer area 6, then the data of 4 unit blocks is stored in the memory 3. There will be.

The data once stored in the memory 3 in this way is stored in the buffer area 6 using the following procedure.

In this case, the processing section 2 causes the bit detection section 5 to detect a unit bit string in which all the vias L are "θ'" from the bit map section 7.

The processing section 2 sequentially writes the values of the bits of each unit bit string a1 to am into the unit bit string register 9 by sequentially rewriting the value of the unit bit string al=am in the bit map section 7 of the address counter 8. And this unit Bi・7
The unit bit strings 81 to al11 in which all four bit values of the bit string register 9 are "0" are detected.

Unit bit strings 81 to a in which all four bits are “O”
When m is found, the unit bit string 81 to am is specified based on the value of the address counter 8 at that time, the unit block of the buffer area 6 corresponding to the first bit is specified, and the number @BI to Bn is the unit. Block number Regisf 10
is maintained.

Then, the processing unit 2 writes a portion corresponding to the data amount of the first unit block of the data stored in the memory 3 to the buffer area 6 according to the unit block number held in the unit block number register 10, and writes the data corresponding to this unit block. Rewrite the bit of the unit pronk number register 10 to "1".

Hereinafter, if there is further consecutive data, the unit block number B1=Bn corresponding to the next bit in the same unit bit string a1 to am is the unit block number register lO
The data is stored in the buffer area 6 accordingly. Of course, at this time, the bit of the corresponding unit block number register 10 is also rewritten to "1" in the same manner as described above.

Finally, the values of the four bits held in the unit bit string register 9 are written to the four bits of the unit bit string of the bitmap section 7 corresponding to the value of the unit bit string held in the address counter 8, thereby converting the data. The writing process to the buffer area 6 is completed.

In the above embodiment, the number of bits of each unit bit string alxam of the bit map section 7 is set to 4, but the number of bits is not limited to this.

〔Effect of the invention〕

As described in detail above, according to the present invention, a plurality of consecutive bits of a bit map are set as a set, and a series of data is stored in a unit block of a buffer area corresponding to these bits. The search time is shorter than the conventional method of searching the bitmap section one bit at a time, and since data is stored in the buffer area in a series of physically continuous areas, data can be read out in a continuous manner. Since reading is performed immediately, no extra search time is required.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a data file device to which the Banofa management system of the present invention is applied. 1... Data processing device 2... Processing section 4...
・File device 5...Bit detection unit 6...
Buffer area 7...Bitmap section 8...
Address counter 9...Unit bit string register
10...Unit block number register patent Applicant: Sanyo Electric Co., Ltd. Agent Patent attorney: Noboru Kono

Claims (1)

[Scope of Claims] 1. A data buffer divided into a plurality of unit blocks, and a bitmap section that indicates whether data is stored in each unit block by turning each bit on or off;
A data file device comprising: a bit detection unit that searches for on/off of each bit of the bitmap portion and detects off bits, and stores data in a unit block of a data buffer corresponding to an off bit. In the buffer management method, the bits in the bitmap section are divided into a plurality of unit bit strings, each consisting of a predetermined number of bits, and when new data to be stored is given, all bits are turned off by the bit detection section. Store the data in the unit block of the data buffer corresponding to the first bit of the unit bit string detected as being present, turn on the bit of the bitmap section corresponding to the unit block in which the data is stored, and store the data. If the data is continuous with the data already stored in the data buffer, detect the off bit in the unit bit string containing the bit corresponding to the last unit block where the already stored data is stored. The data is stored in the corresponding unit block, the bits corresponding to the unit block in which the data is stored are turned on, and if all the unit bit strings are on, a new unit bit string with all bits turned off is detected. A buffer management method for a data file device, characterized in that data is stored in a data file device.