JPS6010329B2 - File control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a file control method that can correctly determine the validity of data in the event of a failure.

In real-time processing, if a failure such as a power outage occurs during file writing, it cannot be determined whether the record being accessed is in the middle of being written or not. Also, when writing the same data to multiple files, for example when writing to a transaction file and updating the master file at the same time, if a failure such as a power outage occurs, which data in the master file will not be updated during the transaction. It is difficult to determine which data should be updated. The present invention is based on the above considerations, and provides a file control method that enables correct determination of file validity during disaster recovery in a file system that includes a transaction file and a master file. is intended to provide. Therefore, in a file system including a transaction file and a master file, the file control method of the present invention provides a preceding stage write counter section and a subsequent stage write counter section for each logical record. , the value of the preceding stage write counter section of the corresponding logical record is updated, and the subsequent stage write counter section is updated after the data writing process for the logical record is completed. Hereinafter, the present invention will be explained with reference to the drawings. FIG. 1 shows an example of the equipment configuration of the present invention, in which 1 is a central processing unit, 2-1 and 2-2 are magnetic disk devices, 3 is an automatic dose sampling device, and 4-1 and 4-4 are magnetic disk devices. 12 each indicate a display.

The system shown in Figure 1 records the radiation doses of workers. The automatic dose reading device 3 is provided in the controlled area, and when a worker enters the controlled area and leaves the controlled area, the amount of radiation exposure of the worker is measured by the automatic dose sampling device 3. The automatically measured exposure amount is recorded in the transaction file and master file. The operator can read the contents of the transaction file or master file using the display 4-1 or 4-2. FIG. 2 shows the relationship between transaction files and master files.

In FIG. 2, 5-1 is missing, 5-3 are transaction files, and 6 is a master file.
For example, transaction 5-1 is an entry/exit transaction file that stores the exposure dose.
FIG. 3 explains the write counter section.

Each logical record of a transaction file has a preceding write counter section C and a final write counter section C.
2 is provided. In the initial state, the front-stage write counter section C and the rear-stage write counter C2 are “
0". Data TR of Mr. A's logical record, (A)
When the first update of is executed, both the front-stage write counter section C and the rear-stage write counter section C2 become "1".
”, and when the second update of data TR,(A) is performed, both the front-stage counter section C and the rear-stage write counter section C2 become "2".However, the data TR,(A) becomes "2".
If a power failure occurs during the second update in A), the front-stage write counter section C2 becomes "2", but the rear-stage write counter section C2 remains "1". Figure 4 shows the sequence.

It is a figure explaining a counter part. When writing Mr. A's data in the transaction file 5-1 to the master file 6, the sequence counter section SCT of Mr. A's logical record in the transaction file 5-1 becomes "1", and the data is transferred to the master file upon completion of writing.・Sequence Kawanta part SCM of Mr. A's logical record in file 6 is also “1”. Mr. B's data T in transaction file 5-2
When writing R2(B) to the master file, the sequence counter SCT of Mr. B's logical record in transaction file 5-2 becomes "2", and when the writing is completed, Mr. B's logical record in master file 6 becomes "2". The sequence counter SCM of the record also becomes "2". When writing Mr. B's data TR3 (B) of transaction file 5-3 to master file 6, the sequence counter section SCT of Mr. B's logical record of transaction file 5-3 becomes "3", and the writing is completed. Upon completion, the sequence counter section of Mr. B's logical record in master file 6 also becomes "3". Transaction file 5-3 A
When writing Mr. A's data TR4(A) to the master file 6, the sequence counter section SCT of Mr. A's logical record in the transaction file 5-3 becomes "4", and when the writing is completed, the A of the master file 6. The sequence counter SCM of his logical record also becomes "4". However, if a power failure occurs during this writing as shown in Figure 5, the sequence counter SCM of the logical record of master file A remains at ``2''. If there is a value in the sequence counter SCT, search for the logical record with the largest value in the sequence counter SCT, find the value in the sequence counter SCM of the logical record in the master file that corresponds to that logical record, and check whether the two match. If they match, it is determined that data writing to the master file has been completed, and if they do not match, it is determined that data writing has not been completed. FIG. 6 is a flowchart illustrating the rewriting process of the write counter units C and C2.

When writing data to a transaction file, first the corresponding logical record is written out from the transaction file, and the contents of the current write counter sections C, , C2 are taken out. If normal, the front stage light counter section C
, and the subsequent write counter section C2 are equal. The contents of the extracted write counter section C, (or C2) are multiplied by 11. Next, write a value incremented by 11 to the first-stage write counter section C, and compete to write data. After the data writing is completed, write a value incremented by 11 to the second-stage write counter section C2. Figure 7 shows the sequence counter sections SCT and S.
It is a flowchart explaining CM rewriting processing.

When writing transaction file data to the master file, a sequence counter SC provided on the main memory is taken out, this value is multiplied by 1, and the result is written to the sequence counter SC again. 11 sequences
The value of the counter SC is written to the sequence counter section SCT of the corresponding logical record of the transaction file, and after writing is completed, the value of the counter SC is written to the sequence counter section SCM of the corresponding logical record of the master file.
Write the value of counter SC. As is clear from the above description, according to the present invention, it is possible to correctly determine the validity of data when a failure occurs.

[Brief explanation of the drawing]

Figure 1 is a diagram showing an example of the equipment configuration of the present invention, Figure 2 is a diagram showing the relationship between transaction files and master files, Figure 3 is a diagram explaining the write counter section, and Figure 4 is a diagram showing the relationship between a transaction file and a master file. Sequence-Counter Section, FIG. 5 is a diagram explaining the state of the sequence counter section when a power failure occurs while writing data of the transaction file 2-1 to the master file, and FIG. 6 is a diagram illustrating the state of the sequence counter section. FIG. 7 is a flowchart illustrating the rewriting process of the write counter section. FIG. 7 is a flowchart illustrating the rewriting process of the sequence counter section. 1...Central processing unit, 2-1 and 2-2...
...Magnetic disk device, 3...Dose automatic discussion device, 4-1 and 4-2...Display, 5-1 none, 5-3...Transaction file, 5...Master・File, C, and C2・”...Write/power counter section, S
CT and SCM...Sequence counter section. Outer figure O2 figure O3 figure Saiko figure ice figure spear figure 5 figure F and 7 figure

Claims (1)

[Claims] 1. In a file system including a transaction file and a master file, each logical record is provided with a preceding write counter section and a subsequent write counter section, and when data is written, the corresponding logical record is A file control method characterized in that the value of a preceding stage write counter section is updated, and the subsequent stage write counter section is updated after data writing processing for the logical record is completed. 2. A sequence counter is provided whose count value is updated by a unit amount each time the data of the logical record on the transaction file is reflected in the master file, and A sequence counter section is provided in each logical record of the file, and when writing the data of the logical record on the transaction file to the master file, the value of the above sequence counter is written to the sequence counter section of the corresponding logical record. After writing of the data corresponding to the corresponding logical record of the master file is completed, the value of the sequence counter is written to the sequence counter section of the corresponding logical record on the master file. A file control method according to claim 1.