JPH04242843A - Subfile management system - Google Patents

Abstract

PURPOSE:To improve the execution performance by reducing the occurrence of wait due to exclusive control for access from plural tasks to a file like a magnetic disk device, etc., in an EDP online system. CONSTITUTION:Subfile management records 4A, 4B, 4C,... the number of which is equal to the number of tasks 1A, 1B, 1C,... are used to manage subfile data record areas 5A, 5B, 5C..., the number of which is equal to the number of tasks 1A, 1B, 1C,..., on a subfile constitution file 3.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a subfile management method in an EDP online system.

0002

[Prior Art] In the EDP online system,
Multiple tasks, the main body of which is a transaction processing program, operate to carry out predetermined tasks. During the process, files are secured on an external storage device such as a magnetic disk device and data is written or read. The need arises. Note that if multiple tasks access the same file area, a contradiction will occur in the data content, so exclusive control must be performed.

[0003] Conventionally, in the file management method of this type of EDP online system, from the viewpoint of effective use of the file area, the file area has been managed in a unified manner using a single file management record. Only the task that secured the record had exclusive access.

0004

[Problem to be Solved by the Invention] As mentioned above, in conventional file management systems, there is a single file management record, so when access is made from multiple tasks, it is necessary to Tasks other than the task are placed in a waiting state under exclusive control, which has the disadvantage that the execution performance of the EDP online system cannot be improved.

The present invention has been proposed in view of the above points, and its purpose is to promote the simultaneous execution of multiple tasks by reducing the waiting time due to exclusive control as much as possible, thereby improving the execution performance of the EDP online system. The purpose of the present invention is to provide a subfile management method that can improve the subfile management method.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides an EDP online system with subfile management records provided in the same number as tasks, and subfile configuration files provided with the same number of subfiles as tasks. It also has a file data record area.

[0007]

[Operation] In the subfile management method of the present invention, the subfile management records provided in the same number as tasks are used to access the subfile data record area provided in the subfile configuration file in the same number as the tasks. is managed.

[0008]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of EDP online business to which the subfile management method of the present invention is applied.

In FIG. 1, tasks 1A, 1B, and 1C correspond to transaction processing programs 2A, 2B, and 2C, respectively, and in this example, there are three tasks. Note that in the EDP online business, the number of tasks is constant.

On the other hand, in a subfile configuration file 3 of a magnetic disk device, etc., three subfile management records 4A, 4B, and 4C, the same number as tasks 1A, 1B, and 1C, are provided in a predetermined area (for example, the leading area). The file area for storing actual data is also divided into the same number of subfile data record areas 5A, 5B, and 5C. In addition, data record areas 5A, 5B, 5 for subfiles
C is divided so that no boundaries are created in the exclusive unit block, and subfile management records 4A, 4B, 4
Two or more Cs should not be provided for one exclusive unit block. In addition, subfile management records 4A, 4
B and 4C contain a flag indicating that they are secured and data record areas 5A and 5 for subfiles to be managed.
It has a bitmap indicating the usage status of each block in B and 5C.

In operation, when the task 1A accesses the subfile configuration file 3, it secures the subfile management record 4A, exclusively uses the subfile data record area 5A, and accesses the subfile data record 6A. Read and write. Similarly, task 1B secures subfile management record 4B, exclusively uses subfile data record area 5B, reads and writes subfile data record 6B, and task 1C secures subfile management record 4C. The subfile data record area 5C is exclusively used to read and write the subfile data record 6C.

[0013] Therefore, even if a plurality of tasks 1A, 1B, and 1C request access to the subfile configuration file 3 at the same time, waiting is less likely to occur.

[0014]

Effects of the Invention As explained above, in the subfile management method of the present invention, since a subfile management record and a subfile data record area are secured in advance for each task, subfile management records and subfile data record areas are reserved for each task. Even if there are requests for access to file configuration files at the same time, there is little waiting time, and the execution performance of the EDP online system can be greatly improved.

[Brief explanation of the drawing]

[Figure 1] ED to which the subfile management method of the present invention is applied
FIG. 2 is a configuration diagram showing an example of P online business.

[Explanation of symbols]

1A~1C...Task

Claims (3)

[Claims] [Claim 1] In the EDP online system,
Subfile management records provided as many times as tasks,
A subfile management method characterized by comprising a subfile data record area provided in the same number of tasks as tasks on a subfile configuration file. 2. The subfile management method according to claim 1, wherein no more than two subfile management records are provided for one exclusive unit block. 3. The subfile management system according to claim 1 or 2, wherein the subfile data record area is arranged so that no boundary is created within the exclusive unit block.