JPH04155546A - Multivolume file processing method - Google Patents

Abstract

PURPOSE:To improve the processing efficiency of a system by setting the information of a file at the file management information of a storage medium, and completing the assignment of the storage area of the storage medium to a multivolume file, at the time of the absence of the empty storage area in the storage medium. CONSTITUTION:At the time of the absence of the empty storage area in the storage medium to which the storage area should be assigned according to a designated sequence, the information of the file to which it is not necessary to assign the storage area is set at the file management information of this storage medium, so that the assignment of the storage area of the storage medium to the multivolume file can be completed. The access control to the multivolume file identifies the presence or absence of the assigned area of this file from the file management information of the volume, and at the time of the absence of the area, the access execution to the data is skipped, and the access to the volume in the next order is performed. Thus, the assigning processing of the storage area can be normally continued even when there is the volume which has no empty storage area in a series of storage media.

Description

[Detailed Description of the Invention] [Summary] Regarding storage area allocation processing for multi-volume files in a computer, even if there is a volume with no free storage area in a series of storage media (volumes), the storage area can be allocated normally. The purpose of this method is to create a multi-volume file processing method that can continue the allocation process, by sequentially allocating a storage area of a required size from the free storage areas of multiple storage media in a specified order according to the specified order. In a computer process that generates a multi-volume file consisting of a plurality of satisfyingly divided storage areas, if there is no free storage area on the storage medium to which the storage areas should be allocated according to the order,
By setting information of the file to which no storage area is allocated in the file management information of the storage medium, it is assumed that the storage area allocation of the storage medium to the multi-volume file is completed.

C. Field of Industrial Application] The present invention relates to a multi-volume file processing method for processing storage area allocation for multi-volume files in a computer.

[Conventional technology]

FIG. 2 is a block diagram showing an example of the configuration of a computer. When a computer generates a file in volume 1 of an individual storage medium that constitutes an external storage installation such as a magnetic disk storage device, multiple storage areas are used. A so-called multi-volume file that is allocated from volume 1 and configured into one file is well known.

Each volume 1 is set with a volume serial number 2 that identifies the volume, and a sequence of multiple volume serial numbers is specified in the configuration information of a multi-volume file, and the file is assigned to the volume with the specified volume serial number. It is controlled so that the storage areas to be allocated are arranged and configured in a specified order.

Therefore, when the file management section 3 of the computer writes out data by specifying the sequence of volume serial numbers of a multi-volume file, there is insufficient space to write the data in the storage area 4 set aside for a certain specified volume 1, and the file management section 3 of the computer If there is no free space, access is made to volume 1 with the volume serial number specified next in the sequence of volume serial numbers.

Read the area management information 5 of the volume, set the area management information to allocate the required size of free storage area to this file, and set the necessary information of the file in the file management information 6. , write the data to the allocated space.

In this manner, when a storage area is needed, the above-described processing is performed for volumes in sequential order.

If there is no free storage space in the volume l to which you are trying to allocate a new storage space, it is treated as an abnormal state in which the process cannot be continued because there is no free space in the specified volume, and the process is treated as an abnormal state in which the process cannot be continued. Abnormally terminate the job that was writing.

[Problem to be solved by the invention]

As mentioned above, if the specified volume happens to have no free storage area, the job will terminate abnormally and the job will have to be re-executed.

An object of the present invention is to provide a multi-volume file processing method that can normally continue the storage area allocation process even if there is a volume in a series of storage media (volumes) that does not have a free storage area N.

[Means to solve the problem]

FIG. 1 is a process flowchart showing the configuration of the present invention.

The figure shows a multi-volume file processing method, in which free storage areas of multiple storage media in a specified order are
In a computer process (processing steps 10 to 16) that sequentially allocates storage areas of a required size according to the order and generates a multi-volume file consisting of a plurality of divided storage areas that satisfy a specified size, If there is no free storage area on the storage medium to which the storage area should be allocated according to the order (processing step 11), set information of the file to which no storage area is allocated in the file management information of the storage medium. As a result, it is assumed that the allocation of the storage area of the storage medium to the multi-volume file is completed (processing step 17).

6. Effect] When an attempt is made to write a multi-volume file using the processing method of the present invention, for a volume with no free space, the multi-volume file does not have a storage area in that volume (only has a dummy area), and the file is Since the file management information is set so that the volume exists and the process proceeds to the next volume, the job can continue processing normally. In controlling access to multi-volume files, it is determined whether there is allocated space for the file based on the volume's file management information, and if there is no space, access to the data is skipped and the next volume is accessed. Process as follows.

〔Example〕

To explain in detail the processing flow shown in Figure 1, the computer starts processing by receiving a sequence of volume serial numbers that specify volumes for writing a multi-volume file. Search and access volumes.

In processing step 11, read the volume area management information,
Identify whether there is free storage space. If there is a free storage area, the storage area is allocated in units of tracks determined by, for example, a magnetic disk storage device, and data is written in the usual manner in processing step 12 and subsequent steps.

That is, in processing step 12, the required number of tracks is determined, and the storage area is allocated by updating the area management information to "allocated" for that area. The required number of tracks is determined by looking at, for example, the number of remaining tracks required for the multi-volume file and the number of free trunks, whichever is smaller.

Once the area is determined, file management information is written in processing step 13, data is written out in processing step 14, and the processing for that volume is completed.

Conceptually, the file management information set within a volume includes a file name that identifies the file, a pointer that indicates the first track of the allocated area, the number of tracks, and the order of the volume within the multi-volume file. have information

After writing the data, it is determined whether further area acquisition is necessary in processing step 15, and if it is not necessary, the processing is terminated.If necessary, the next priority volume is accessed in processing step 16, and processing step 11 is performed. Return to processing.

In processing step 11, read the volume area management information,
If there is no free storage area, the process of step 17 is performed according to the present invention. In processing step 17, the same file management information as in processing step 13 is set in the volume, but since there is no allocated area, for example, the pointer to the first trunk is set to 01, and the number of allocated tracks is also set to 0. Thereafter, the process proceeds to step 16 to access the next volume.

With the above processing, for example, multi-volume files with file names A and B can be created with volume serial numbers ■1, ■2, ■
When writing to volume 3 of 3, assuming that there is no free space in volume 2, file management information as illustrated in FIG. 3 is set in each volume.

It is assumed that the length of the required storage area of the multi-volume file in this example is 50 tracks.

When accessing this file, you can search the file management information by file name, check the normal order in the volume order, and process the access as before, but in this case, for example, check the pointer. and then 0
If so, proceed to the next volume without accessing the data in that volume.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, in storage area allocation processing for multi-volume files in a computer, even if there is a volume with no free storage area in a series of volumes, the storage area can be allocated normally. Since the processing can be continued, the occurrence of re-execution due to abnormal termination of the job can be avoided, and this has a significant industrial effect of improving the processing efficiency of the system.

[Brief explanation of the drawing]

FIG. 1 is a process flowchart showing the configuration of the present invention, FIG. 2 is a block diagram showing an example of the configuration of a computer, and FIG. 3 is a diagram explaining file management information. In the figure, 1 is the volume, 2 is the volume serial number, 3 is the file management section, 4 is the storage area, 5 is the area management information,
6 is file management information; 10 to 17 are processing steps; FIG. 1 is a process flowchart showing the configuration of the present invention;

Claims (1)

[Claims] A storage area of a required size is sequentially allocated from free storage areas of a plurality of storage media having a specified order, and a plurality of divided storage areas satisfying the specified size are created. In the computer process of generating a multi-volume file consisting of storage areas (10 to 16), if there is no free storage area on the storage medium to which the storage areas should be allocated according to the order (11), the file on the storage medium is A multi-volume file characterized in that by setting information of the file to which no storage area has been allocated in the management information, it is assumed that the storage area allocation of the storage medium to the multi-volume file has been completed (17). Processing method.