JP2539347B2 - File management method - Google Patents

Description

The present invention relates to a file management method in an electronic computer having an auxiliary storage device, and more particularly to a file management method capable of executing a file OPEN process at high speed.

[Prior art]

FIG. 1 shows a method of a conventional file management system. Reference numeral 1 denotes a randomly accessible auxiliary storage device such as a magnetic disk device (hereinafter abbreviated as disk), 21
Numerals 22 and 22 are files, and 31 to 35 are tables for managing the files, which are usually called file labels and store the file attribute information such as the file name, physical position, knitting method and record length. . 4 is a main memory, 41 is a system common area of the main memory, 42 is a user program area, 5 is a file management system program, and 51 is OPEN.
Macro instruction program, 61 and 62 are user programs,
Reference numerals 71 and 72 are management tables used by the program of the file management system.

In order to access the file, it is necessary to read the information of the file label from the randomly accessible auxiliary storage device 1 onto the main storage device 4, and normally this processing is performed by the OPEN macro instruction program.

This macro instruction program has a function of producing a macro instruction, that is, a fixed-form program at the time of assembly, and saves the trouble of repeatedly writing the same program.
The system programs are characterized in that they are connected with each other, are systematized precisely, and are particularly useful in system programs with severe connection conditions.

In the conventional file management system, as shown in FIG. 1, the information of the file labels 31-35 is read into the management tables 71-72 in the user program. For example, when the user program 61 issues an OPEN macro command to the file 21, the OPEN macro command program 51 reads the information of the file label 31 that manages the file 21 into the management table 71 in the user program 61. When another user program 62 also issues an OPEN macro instruction to the file 21, the OPEN macro instruction program 51
The information of the file label 31 is read into the management table 72 in the user program 62.

In this way, since the file label information is read into the management table in the user program, the following problem occurs.

Even if another user program opens the same file,
The information of the same file label that has already been read by one user program cannot be used as it is, and the file label must be read separately from the disk, which results in unnecessary access to the auxiliary storage device. .

It is difficult to manage the contents of the management table in the user area by file management, and it is necessary to read the file label every time even when one user program is repeatedly started.

In order to solve these problems, a file management system having the configuration shown in FIG. 2 has been devised. (Hitachi: HIDIC
−80 Series Software Manual Data Management DMS
In FIG. 2, 1,21,22,31 to 35,4,41,42,5,51,61,62 are the same as in FIG. 1, respectively. Instead of deleting the management table used by the file management system program, the system common area of the main memory
Management tables 81 to 83 that store the attributes of files in 41
And file labels 31 to 35 to 81 to 83 on the auxiliary storage device
There is a utility program 9 for creating a management table of.

In this method, the utility program 9 reads the file labels 31 to 35 in advance to create the management tables 81 to 83 in the main memory 4, and when the files are opened, the management tables 81 to 83 are used. It is searched and used, and access to the file label on the auxiliary storage device is unnecessary.

However, this improved method still has the following problems. That is, a table containing file attribute information is
Since it needs to be created in advance by the utility program 9, if the number of files is large, the capacity of this table becomes enormous.

[Object of the Invention]

The object of the present invention is to improve the conventional drawbacks as described above, in the file OPEN processing, while limiting the capacity of the management table on the main storage device, the file label from the randomly accessible auxiliary storage device such as a disk is added. It is to provide a file management method that can reduce the process of reading and read the OPEN process at high speed.

[General Description of Invention]

In order to achieve the above object, the present invention employs the following method.

When the OPEN macro command is issued again for the same file by leaving the file management table on the response table even after the file has been used, the file attribute information created by the program reading the file label. For this, the file attribute information on the file management table created and left in the previous OPEN processing is used.

On the other hand, when a large number of files are opened, there is no space in the file management table, and another file management table will be overcoated and used. However, for files that require high-speed OPEN processing, it is necessary to prohibit overcoating of this file management table. Therefore, the macro command program (POPEN) that reads the file label and creates this file management table and prohibits overpainting
And macro instruction program (PCLOS
E) is provided.

[Examples of the Invention] The outline of the present invention will be given below before the detailed description of the examples.

The file management table created by the OPEN macro program is placed in the system common area on the main memory so that multiple tasks can use it in common.

The file management table created by the OPEN macroinstruction program by reading the file label from the randomly accessible auxiliary storage device is used after the file is used, that is, CLOS.
Leave without erasing even after E.

In the file OPEN processing, first, the file management table is searched to determine whether the attribute information of the target file has already been created.

If the file attribute information of the target file already exists in the file management table, use this information,
If it does not exist, one case of this file management table is secured, the file label is read from the randomly accessible auxiliary storage device, and the file attribute information is set to the secured case.

To secure the case of the file management table mentioned above,
Perform as follows. If there is an empty case, the empty case is used. If there is no empty case, the case with the file attribute information is overcoated and used. For files that particularly require high-speed OPEN processing, a flag for prohibiting overcoating is provided on the file management table, and when this flag is set, overcoating is prohibited. A macro instruction program (POPEN) for creating the management table and setting the overpainting prohibition flag and a macro instruction program (PCLOSE) for resetting the overpainting prohibition flag are provided.

 An embodiment of the present invention will be described below with reference to FIGS.

 The entire structure of the present invention is shown in FIG.

1 is an auxiliary storage device capable of random access, 21 and
22 is a file.

Reference numeral 12 is a table called VOL1, which stores the following two pieces of information. One is information for identifying the volume such as the volume name and the owner of the volume, and the other is all file labels 31 to 34 and the bit map described later.
It is address information of the file label 31 for managing 13.

Reference numeral 31 manages all the file labels 31 to 34 and the bit map 13, and file labels 32 to 34 manage the files on the auxiliary storage device 1 that can be randomly accessed.

Numeral 13 is a bit map for managing the use condition of the space on the randomly accessible auxiliary storage device. The random access auxiliary storage device is divided into fixed-length blocks, and each block is in use as a file. Whether or not it is expressed by one bit of information and managed.

In FIG. 3, 4 is a main memory, 41 is a system common area of the main memory, and 42 is a user program area.

5 is a file management macro program group of the file management system, 51 is an OPEN macro instruction program, and 52 is
CLOSE macro instruction program, 53 is POPEN (Pre-OPEN)
Macro instruction program 54 is a PCLOSE (Pre-CLOSE) macro instruction program.

Reference numeral 15 is the file management table described above, which is FC here.
It is called T (File Control Table) and stores file attribute information and file status information.

14 is called VUCT (Volume Unit Control Table),
This table is used to find the target volume from the volume name. Therefore, the association between the name of the volume, the unit number of the unit in which this volume is united, and the file label group of this volume and the FCT number indicating the FCT that manages the bit map is stored.

16 is called SSPT (Search Start Pointer) and is an empty FCT
When the FCT in use is overcoated, the FCT number for starting the process of searching for the FCT to be overcoated is stored.

17 is called FFC TPT (Search Start Pointer) and is empty FCT
It is for managing the FCT number and stores the first FCT number of the empty FCT that is formed by connecting the empty FCTs in a list.

 An area 160 stores the number of cases of FCT15.

61 is a user program and 100 is a procedure part of the user program.

Reference numeral 18 is called a RAT (Record Access Table) and is a table having two functions. One is a function of transmitting information instructing access to a file of the user program to the macro instruction program of the file management system, and the other is a function of storing what kind of file access the user program is making. Is.

The address of this table is passed to the macro instruction program as a parameter of the macro instruction program for reading the file. Reference numeral 101 is a buffer area, which is used for reading a block including a target record and extracting a target record from the block.

19 is an area for specifying records or blocks,
The user can specify the record number etc. to be accessed in this area.
Set by the program.

20 is a data area in which a record is fetched or the record set in this area is written in the file.

Fig. 4 shows details of the file label. The file label manages files and groups of file labels and bitmaps (they also see one file), in which the file name 301, file format 302 indicating the file knitting method, and information on extents forming the file are included. (Extent address and extent length 303
~ 306), file block length 307 and file attribute information such as record length.

 FIG. 5 shows details of the management table on the main memory.

Reference numeral 14 is a VUCT, and the field 141 has the vorium name, the field 142 has the unit number of the unit in which this volume is mounted, and the field 143 has the field 143 that is the FCT number of the FCT that manages the file label group and bit map. I remember each.

Reference numeral 15 is an FCT group, and each FCT manages a file or a file label group and a bit map, and stores its attribute information and state information. File FCT on the same volume
Starts with the FCT that manages the file label group and bit map of this volume, and the ring pointer 155 ~
They are connected in a ring shape by 159. For example, VUCT 1st
In the case of the volume controlled by the case eye, the file label group and bit map of this volume are managed.
The ring pointer of FCT151 also points to FCT153, which also manages the files in this volume. Since there is no other FCT that manages the file on this volume, the ring pointer of FCT153 points to the first FCT, and the FCTs related to the same volume are connected in a ring shape. The FCT number of the FCT to be pointed to is entered in the ring pointer. This first FCT is created as long as the system is booted or mounted at the volume mount, the overcoat prohibited bit is set, and the volume is mounted. The details of FCT will be described in Fig. 6.

16 is SSPT (Search Start Pointer) as described above.
Is.

17 is FFCTPT (Search Start Pointer) and is empty FCT
F at the beginning of the empty FCT list in which the
The FCT number of CT is stored.

160 stores the number of FCT cases. F without empty FCT
When CT is overcoated and used, the FCT pointed to by the SSPT is sequentially searched for a usable FCT. If the last FCT is not available, search back to the first FCT. For this reason, information on the number of FCT cases is necessary.

The table on the left side of the one-dot chain line in FIG. 5 described so far exists in the system common area of the main storage device, and the table to be described below is in the user program area.

Reference numeral 18 denotes a RAT (Record Access Table), which is a table mainly for transmitting a file access request to a file management system and stores two types of information. One is
Access instruction information to file management macro instructions such as address 183 of the data specification area 19 and address 184 of the data area, which is the area for reading records or blocks, in which the user sets information such as the record number of the record to be accessed. Is. The other is file access by the user, such as the number 182 of the record to be accessed next, the FCT number 181 of the FCT currently being accessed, the address 185 of the buffer area 101 being used, etc. when sequentially accessing the records. It is the information of the running state.

Figure 6 shows the details of FCT. FCT153 is a file name 165,
File format 166 indicating the file organization method, information on extents forming the file (extent address,
Extent length 167-170), file block length 171
And record length 172 such as file attribute information, as well as O bit 161, P bit 162, U bit 163, A bit 164, and other file status information, and a ring pointer 158. .

An O bit 161 is a bit indicating whether or not the file is OPEN, and 1 indicates OPEN and 0 indicates that it is not OPEN.

P bit 162 is a bit indicating that POPEN (Pre-OPEN) described later is being performed, where 1 indicates that POPEN is in progress and 0 indicates that POPEN is not in progress.

U bit 163 is a bit indicating that a file managed by the FCT is being defined or deleted, 1 indicates that the file is being defined or deleted, and 0 indicates that this file cannot be used. .

A bit 164 is a bit indicating whether or not the file attribute information on the FCT has been updated, and if it is 1, it indicates that the file attribute information has been updated, and it is necessary to update the file label on the auxiliary storage device when the file is closed. Is. 0 indicates not changed.

Next, based on the above management table, OPEN, CLOSE, POPEN
The logic of each macro instruction program of (Pre-OPEN) and PCLOSE (Pre-CLOSE) will be described with reference to the flow charts of FIGS.

Figure 7 shows the OPEN macro flow chart. OPEN
The macro instruction program prepares the file before accessing it. Creating FCT and RAT,
Performs processing such as occupying files and securing buffers.

In step 801, an FCT is created. It is an object of the present invention to perform this processing at high speed, and the details thereof will be described later with reference to FIG.

In 802, O bit 161 and U in the FCT of the target file
If the bit 163 is determined and if either one of them is 1, it is determined that the target file is occupied, and a return code to that effect is returned to the user program at 806.

In 803, when the target file is not occupied, the buffer area is secured and the buffer area address 185 in the RAT is set.

At 804, 1 is set in the O bit 161 of the FCT of the target file to indicate that it is OPEN, and the file is occupied.

In 805, the access information of the user with the FCT number 181 or code number 182 of the target file is initialized in the RAT.

Figure 8 shows the flow chart of the FCT creation process. Prior to explaining this flow chart, a method of specifying a file for the OPEN macro instruction program will be described with reference to FIG.

The VOL name 909 in FIG. 9 is a volume name, which is specified in the order of VOL name, colon, and file name 910.

Returning to FIG. 8, the VOL name specified in 901,902
The field 141 storing the VOL name in the VUCT 14 is sequentially searched based on 909 to find a case where the VOL names match. If there is no match, then at 908 a return code of unmounted volume is returned. FC for this case, if a matching case exists
From the T number field 143, obtain the FCT number of the FCT that manages the file label and bit map of the relevant volume. The FCT of the file on the corresponding volume is this FCT
Since it is connected in a ring shape with a ring pointer starting from, the F name is based on the specified file name 910.
The ring pointer is searched for the FCT in which the file name 165 on the CT matches (903).

The presence / absence of the FCT of the corresponding file is determined at 904, and if there is the FCT, it is not necessary to create the FCT again, and the processing ends. If it does not exist, one case of FCT is secured by the method described in FIG. 10 in 905, the file label of the specified file is read from the randomly accessible auxiliary storage device in 906, and file attribute information is set in the FCT. To do.

At 907, the created FCT is added next to the beginning of the FCT ring of the relevant volume.

Figure 10 shows how to secure the FCT. As I said, F
To create a CT, it is necessary to secure an FCT, but as will be described later, the FCT is not erased even after the file is closed, so there is a high possibility that an empty FCT will be lost.
The problem is whether to use CT overcoat.

In 1001 of Fig. 10, FFCTPT17 (Free FCT Poin Ter)
If it is “0”, it is considered that there is no empty FCT. If not, the process proceeds to 1002, where SSPT (Search
From the FCT with the FCT number stored in the Start Poin Ter) 16, the FCTs in which the O, P, U, and A bits are all "0" are searched for in the order of the FCT numbers. If the FCT number exceeds the FCT number stored in 160, it returns to the first.

In addition, manage the file label and bit map.
P-bits should be set up in FCT to prevent overcoating.

In 1003, the FCT number of the FCT next to the FCT that secures the SSPT16 value is used. "1" if the secured FCT is the last FCT
Set.

1004: Empty FCT if empty FCT is connected to FFCTPT
The first FCT in the list, that is, the FCT pointed to by FFCTPT17
Is assigned, and the FCT number pointed to by the assigned FCT ring pointer is set in FFCTPT17. By moving the start point to search for the FCT to be overcoated in this way, the relatively latest FCT will be left without being overcoated.

Figure 11 shows the flow chart of the CLOSE macro command program. At 1101, the A-bit 164 of the FCT is determined, and if the A-bit is "1", it is determined that the file label needs to be updated, and the 1102 file label update processing is performed. If A
If the bit is "0", it is not necessary to update the file label, so skip 1102.

In 1102, the attribute information of the file which is included in both the FCT and the file label, for example, extent information is written in the file label.

At 1103, since the file is changed from the OPEN state to the other state, the F bit O bit 101 is reset.

At 1104, the information in the buffer 101, which is not reflected in the disk, is reflected in the randomly accessible auxiliary storage device, so that the information in the buffer 101 is written in the auxiliary storage device.

As described above, in the CLOSE macro instruction program, only the O bit is reset without erasing the FCT.

Figure 12 shows the flow chart of the POPEN macro instruction program. At 1201, the FCT of the designated file is created by the method shown in FIG.

At 1202, the P bit 162 of the FCT is set. As a result, this FCT is prohibited from overcoating as explained in FIG. 10, and until this PCLOSE macro command is issued, the FC
T can be continued, and file OPEN processing can be performed without reading the file label.

FIG. 13 shows the flow chart of the PCLOSE macro instruction program. In 1301, VCT is searched for VCT as in the case of OPEN processing.

In 1302, it must be POPENed, and the FCT exists, but it is possible that a PCLOSE macro is issued to a file that is not POPENed, so the presence or absence of the FCT is determined.

At 1303, if the FCT exists, the P bit 162 of the FCT is reset.

In 1304, if the FCT does not exist, the return code of not-POPEN is set and the process returns to the user program.

Based on the explanation of the logic of the table and macro described above, the characteristics of the present invention will be clarified by taking FIG. 14 as an example.

In FIG. 14, 14 is a VUCT, 15 is an FCT, 1 is a disk and has a volume name of VOLA, 21 is a file with a file name of A, 22
Is a file with a file name B, 23 is a file with a file name C, 31 to 35 are file labels, and 13 is a bit map.

For example, if a disk 1 with a volume name of VOLA is registered in VUCT14 during system generation, a file label and FCT for bit map, the first case in FIG. 14, are created at system startup.

After system startup, pope files A and B
When the N macro instruction is issued, the FCT of files A and B
Is created.

Then the user program starts to move the file to C, A, B,
Suppose you used them in the order C. OPEN of the first file C
Now, read the file label 34 and create an FCT. Second
In the second OPEN of file A, the FCT has already been created, and it is not necessary to read the file label, and OPEN processing can be performed at high speed. Similarly to the case of A, the FCT of the third file B is already created by the POPEN macro instruction, and it is not necessary to read the file label, so that high speed OPEN is possible.

Although POPEN has not been done in the fourth OPEN of file C, the FCT remains created, so there is no need to read the file label, and high-speed OPEN processing is possible.

That is, by reusing the information of the file label, and allocating the most frequently used information to the main memory preferentially, the small management table capacity and high speed are achieved.
OPEN processing becomes possible.

〔The invention's effect〕

According to the present invention, it is possible to provide a file management method for quickly opening a file that has been opened at least once.

[Brief description of drawings]

FIG. 1 is a diagram showing a control system of a conventional file management system, FIG. 2 is a diagram showing a control system of a file management system in which all file label information is resident, and FIG. 3 is a file management of the present invention. FIG. 4 is a diagram showing a management table on a main storage device and an auxiliary storage device of the system, FIG. 4 is a diagram showing a file label of the file management system of the present invention, and FIG. 5 is a main storage device of the file management system of the present invention. Fig. 6 shows the management table, Fig. 6 shows the FCT, Fig. 7 shows the flow chart of the OPEN macro instruction program, and Fig. 8 shows the FCT.
Creation process flow chart, Fig. 9 shows the file specification method for the OPEN macro instruction, Fig. 10 shows the FCT reservation flow chart, Fig. 11 shows the CLOSE macro instruction program flow chart, and Fig. 12 shows POPEN. FIG. 13 is a flow chart of the PCLOSE macro instruction program, and FIG. 14 is an explanatory diagram for clarifying the effect of the present invention. 1 ... Auxiliary storage device such as a disk, 21-23 ... File, 31-35 ... File label, 4 ... Main storage device, 41
...... Main memory system common area, 42 …… Main memory user program area, 5 …… File management macro program group, 61 to 62 …… User program, 71 to 72 ……
File management table in user program, 81 to 83
…… A table that stores file attributes, 9 …… A utility program that creates 81-83, 12 …… VOL1, 13…
… Bitmap, 14 …… VUCT, 15 …… FCT, 16 …… FCT search start pointer (SSPT), 17 …… Empty FCT pointer (FFC
TPT), 18 …… RAT, 51 …… OPEN macro instruction program,
52 …… CLOSE macro instruction program, 53 …… POPEN macro instruction program, 155 to 159 …… Ring pointer, 161…
… O bit, 162 …… P bit, 163 …… U bit, 164
...... A bit.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiyuki Kuwana 5-2-1 Omika-cho, Hitachi City Inside the Omika Plant of Hitachi, Ltd. (56) Reference JP-A-57-106953 (JP, A)

Claims (2)

(57) [Claims] 1. A file management method in an electronic computer system having an arithmetic processing unit, a main storage unit and an auxiliary storage unit, comprising: (a) a storage area for storing management information of files stored in the auxiliary storage unit. (B) When a file on the auxiliary storage device is opened, information on the searched file, such as a file name, about the file itself, and on the auxiliary storage device, File management information including file storage information and link information indicating a relationship with another file is stored in the storage area, and (c) when the file is opened at another time, the file management information is stored. When searching using the link information and the information about the file itself in the file management information indicates the file name of the file , The file management method using the stored information of the file of the file management information, characterized by open the file. 2. The storage system according to claim 1, wherein when the file management information is stored, the empty area is used if there is an empty area in the storage area,
A file management method characterized in that, when there is no free area, the new file stores management information sequentially from the area that was previously stored in the storage area.