JPS6162923A - Access system for file - Google Patents

Abstract

PURPOSE:To retrieve a physical address at a high speed by providing an area where physical addresses of files stored on a disk are stored, and storing file names and physical addresses of files which are accessed frequently in the area. CONSTITUTION:A processor 1 reads a program out of an ROM3 and begins to operate, and stores a program from a disk 6 in an RAM2 through a disk control circuit 7. This RAM2 is provided with a VTO (control ledger) reference tape 20 and the processor 1 extracts a file which is used frequently and stores its file name and physical address. When this storage area becomes full, the file which is stored for the 1st time is expelled and a new file is stored. Consequently, the processor 1 refers to said table 20 when reading a file out of the disk 6 and then reads the file in a following physical address from a target sector number if finding the target file name.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for accessing files stored in an external storage device such as a disk, and particularly relates to a system for accessing a file stored in an external storage device such as a disk, and particularly relates to a system for accessing a physical address indexing time required to access the file. This invention relates to an external storage file access method that shortens the process.

Recently, with the spread of various information processing devices, many intelligent terminal devices have come into use.

The functions of this intelligent terminal device have also been expanded, and it is necessary to store and process a large number of files, and these files are usually stored in an external storage device such as a disk with a large storage capacity.

Generally, files stored in an external storage device are sequentially stored on a disk or the like in the order in which they were created, and are assigned physical addresses. Therefore, the physical address of the latest file that is accessed most frequently is assigned last, but it is necessary that the time required to index the physical address of this latest file does not become long.

[Conventional technology]

FIG. 3 is a block diagram of a circuit showing an example of an intelligent terminal device.

The processor 1 reads the program for initial program loading stored in the ROM 3, starts operation, and loads the program from the disk 6 via the disk control circuit 7.
Store in AM2. It operates according to instructions from this program.

Commands and data are input from a keyboard 9 operated by an operator via a keyboard control circuit 8. The processor 1 executes the job based on this instruction, creates a file based on the input data, and temporarily stores it in the RAM 2. Furthermore, files from the higher-level device that enter through the interface control circuit 10 are also temporarily stored in the RAM 2. Furthermore, the display control circuit 4 is controlled to display the data to be displayed on the display section 5.

Here, the processor 1 sequentially controls the disk control circuit 7 to sequentially store the files once stored in the RAM 2 on the disk 6. In this case, the files are stored on the disk 6 in the order in which they were created.

FIG. 4 is a diagram illustrating an example of the configuration of a disk.

For example, in the case of a magnetic disk, there are a plurality of magnetic disk disks as shown in 11 to 14, and each magnetic disk disk 11
14 are formed with a plurality of tracks, and all the trunks located at the same distance from the rotating shaft 19 form one unit called a cylinder.

For example, numbers 15 to 18 indicated by dotted lines are one cylinder.

The trunk is also divided into multiple areas called sectors.

51st! I is a diagram illustrating an example of a method for managing files stored on a disk.

For example, as shown in FIG. 5, in the cylinder trunk 15 in FIG. 4, a management ledger called VTOC is formed following the volume label. That is, the VTOC list is written in the order in which files are stored on the disk, such as A, B, and C.

This list consists of control information, followed by location information as the file name, cylinder number indicating the physical address, trunk number (sometimes indicated by a head number), and sector number, followed by the usage status of this file. It's included.

Files are transferred to the magnetic disk disk 12 according to the physical address consisting of this cylinder number, trunk number and sector number.
, 13, 14. Therefore, when reading a file stored on disk 6,
By reading the corresponding physical address from the file name of the above location information in the trunk 15 and knowing the storage location of the target file, it is possible to access the file.

[Problem that the invention seeks to solve]

In order to read a file stored on a disk, as in F.-F, it is first necessary to index the physical address indicating the storage location based on the file name of the target file. This physical address index requires the physical operation of positioning the head on the trunk 15 in FIG. 4 and sequentially reading out the position information of the VTOC list starting from the volume label.

As mentioned above, the newest files are recorded at the end of the VTOC list, so as the number of files stored on the disk increases, it takes more time to index the physical addresses.

Recently, disks with slow access but large capacity, such as micro disks, are being used, and in this case, a particularly large amount of time is required, and since the latest files have more opportunities to be accessed, the physical address The loss of indexing time is large and requires countermeasures.

[Means for solving problems]

The problem described above is that in a system that includes a storage device that stores a plurality of files and a high-speed storage unit, and reads the files from the storage device and processes them, the high-speed storage unit stores the files stored in the storage device. A table for storing addresses is provided, the physical address of the most recently accessed file is stored in the table, the physical address of the oldest accessed file is controlled to be deleted, and when accessing a file on the storage device, This problem is solved by the file access method of the present invention, which refers to the table.

[Effect]

In other words, an area is provided in the high-speed storage unit to store the physical addresses of files stored on the disk, which is a storage device, and this area is used to store the file names and physical addresses of multiple frequently accessed files. By erasing old files and storing new ones in their place, the physical addresses on the disk of frequently accessed files can be retrieved in high-speed storage.

〔Example〕

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

Figure 1 shows the VTOC reference table 20 in RAM2 in Figure 3.
Figure 2 shows this VTOC reference table 2.
It is a figure which shows an example of 0.

As shown in FIG. 2, the processor 1 extracts files that are frequently used on a daily basis and stores the corresponding file names and physical addresses. That is, file a and its cylinder number, trunk number, and sector number are stored. If the storage area becomes full, the first stored file n is evicted and a new file is stored in the location of file a.

That is, an update method is used in which when a new file is entered, an old file is removed.

Here, when the processor 1 does not read the file from the disk 6, in order to know the storage location of the file, it first reads the V of the RAM 2.
Refer to the TOC reference table 20. If you find the desired file name in the V T' OC reference table 20,
The next physical address is used to immediately position the head to the cylinder where the file exists, and the file is read from the target sector number.

If the desired file name does not exist in the VTOC reference table 20, the VT
Read the OC list and index the target file name. In this case, as mentioned above, enter this file name and physical address in the VT
Stored in the OC reference table 20.

The number of files stored in the VTOC reference table 20 is RA
An appropriate selection can be made depending on the capacity of M2 and the number of files stored on the disk.

(Effects of the Invention) As explained above, when reading a file stored on a large-capacity, slow-access disk, the present invention makes it possible to omit the time required to index the physical address of a file that is frequently read. .

[Brief explanation of drawings]

FIG. 1 is a block diagram of a circuit showing an embodiment of the present invention, FIG. 2 is a diagram showing an example of a VTOC reference table, FIG. 3 is a block diagram of a circuit showing an example of an intelligent terminal device, and FIG. 4 is a block diagram of a circuit showing an example of an intelligent terminal device. FIG. 5 is a diagram illustrating an example of the configuration of a disk, and FIG. 5 is a diagram illustrating an example of a method for managing files stored on the disk. In the figure, 1 is a processor, and 2 is a RAM. 3 is a ROM, 4 is a display control circuit, 5 is a display section, 6 is a disk, 7 is a disk control circuit, 8 is a keyboard control circuit, 9 is a keyboard, 10 is an interface control circuit, 11 to 14 are magnetic disk disks, 15 to 18 are trucks that constitute one cylinder, 1
9 is a rotation axis, and 20 is a VTOC reference table.

Claims (1)

[Claims] In a system that includes a storage device for storing a plurality of files and a high-speed storage unit, and reads and processes the files from the storage device, a table stores physical addresses of files stored in the storage device in the high-speed storage unit. The table stores the physical address of the most recently accessed file, controls to delete the physical address of the oldest accessed file, and refers to the table when accessing a file in the storage device. A file access method characterized by: