JPH03223937A - Using method of shared data area - Google Patents

Abstract

PURPOSE:To directly handle the data requiring the fast processing as well as a 2-dimensional table by adapting a data space serving as a shared data area that can be exclusively controlled and recovered and therefore enabling the users to use a data area where the table can be handled with guarantee of data. CONSTITUTION:A shared data table 1 is provided together with the table corresponding control information 2, a shared area access subroutine 3, a user program 4, and a recovery task 5 which evolves the table 1 to an inter-process shared area in an abnormal state. Then the data processing accompanied with the exclusive control is carried out among plural processes against an optional shared data area of a main storage. At the same time, the shared data area is automatically recovered at abnormality of a program. Thus the availability of an inter-process shared area is improved as a data space.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of using a shared data area, and particularly to improving data security and handling/high speed during data processing.

[Conventional technology]

Electronic Data Pr
(processing) system, the sophistication of data processing,
There is a need for responsiveness to increasing complexity. Therefore, as a trend in EDP systems, improving the handling/high speed of data to be processed is becoming an increasingly important issue.

In this context, focusing on the data space, conventionally the data space existed as a data buffer in which data blocks of a file were stored, and data handling there was performed on a record-by-record basis using input/output instructions. It will be done.

[Problem to be solved by the invention]

However, such a data space cannot be expected to be used as a space for storing data that requires high-speed processing, and it is also not possible to directly handle two-dimensional tables.

In other words, as mentioned above, the only handling method is to handle records in units of records using input/output commands.
Therefore, it is not easy to meet the demand for high-speed processing, and furthermore, in order to process it as a two-dimensional table, it is necessary to transfer it to the work area, so direct table handling processing cannot be expected.

On the other hand, if we focus on the shared area on the system's main memory,
There are difficulties in terms of data security.

That is, the shared area on the main memory does not have functions such as exclusive control and recovery, and its range of use is naturally limited, and it cannot be used as a data area with data security.

As described above, in the former case, in the conventional method described above, there are constraints on data handling when data is expressed as a file, namely: There are problems such as ■The processing unit is a code, and ■It cannot be handled as a two-dimensional continuous data space.In the latter case, when data is expressed in a shared area on main memory, There is no guarantee as data, and there are problems such as: ∎ Logical inconsistencies may occur depending on the timing when updated by multiple processes; ∎ Updated data cannot be recovered in the event of a program error, etc.

The present invention has been made to solve the above problems, and its purpose is to add exclusive control and recovery functions to the conventionally existing inter-process shared area, so that it can be used as a data space. The object of the present invention is to provide a method of using a shared data area that can expand the usage of the data area.

[Means to solve the problem]

The present invention is a method of using a shared data area in a data processing system, which performs data processing with exclusive control among multiple processes for any shared data area existing on main memory, and also handles program abnormalities. Sometimes it is characterized by automatic recovery.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, in which ACO3-4
An example of application to ADBS/ViS is shown.

In FIG. 1, reference numeral 1 indicates a table as shared data realized on an inter-process shared area. Shared data table 1 is table ■, table ■ in the example shown in the figure.
, table ■, and constitutes a space that can be shared and accessed by multiple processes.

In this embodiment, in addition to the shared data table 1, as shown in the figure, management information 2 corresponding to the table, a shared area access subroutine 3, a user program 4, and an abnormality data table as described later are developed in the inter-process shared area. It has recovery task 5.

The management information 2 corresponding to the table is management information for managing the state of the shared data table 1, and is used to check the table access right, that is, whether or not it can be used. It is.

The shared area access subroutine 3 includes a table use request (exclusive control start request), table handling processing, table use end (exclusive control end), and in addition to checking table access rights, etc.
Reference and update the data table via the base (BASE) address. Shared area access subroutine 3 is
It is called by the application task (user program execution task) of the user program 4.

The user program 4 notifies the recovery task 5 of the abnormality in order to perform automatic recovery when the program is abnormal. In this case, recovery task 5 is a backup of the inter-process shared area (Backup
The data table is expanded from the electronic disk file 6 (up) to the inter-process shared area to perform recovery in the event of an abnormality.

In addition, the part with reference numeral 7 in the figure represents the exchange of data with the electronic disk file 6 as a backup file.

The shared data space according to the present invention has the following functions: a space that can be shared and accessed by multiple processes (inter-process shared area), and a user can arbitrarily control the data (usually tables) existing in the inter-process shared area. A function that allocates resources and subjects them to exclusive control.
By realizing each function of the data purging (backup) function for the electronic file (semiconductor memory file device) serving as the main memory, the data space to be recovered that can be controlled exclusively is opened to the user. By adopting a secure data space, users can use a data area that can be processed through table handling with data guarantee.

Specifically, exclusive control between multiple processes over any shared data area existing on the main memory and automatic recovery in the event of a program error can be performed as follows.

First, in FIG. 1, a user program (application task) 4 calls a shared area access subroutine 3 and passes control to the shared data table 1 implemented on the inter-process shared area in order to process this data. .

Next, a table use request is made in response to a request from the user program 4 in the shared area access subroutine 3. At this time, the shared area access subroutine 3 checks the table access rights (usability), etc. using the management information 2 corresponding to the table, and if the table is normal, exclusive control of the shared data table 1 is performed. , and refer to and update the corresponding data table via the base address of the data table. Further, when the processing is completed normally, the corresponding data table is swept out to the electronic disk file 6.

In the normal case, the above-mentioned processing is performed.

On the other hand, when the application task of the user program 4 terminates abnormally, the recovery task 5 is notified, and the recovery task 5 expands the corresponding data table from the electronic disk file 6 into the inter-process shared area. This allows automatic recovery to occur in the event of an abnormality.

In this way, it is possible to achieve exclusive control among a plurality of processes over any shared data area existing on the main memory, and it is also possible to automatically perform recovery in the event of a program abnormality.

〔Effect of the invention〕

As explained above, according to the present invention, by adopting exclusive control and a data space as a recoverable shared data area, a user can use a data area that can be processed by table handling with data guarantee. As a result, the space can be used as a space for storing data that requires high-speed processing, and two-dimensional tables can also be directly handled.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of the present invention. 1... Shared data table realized on the inter-process shared area 2... Management information for managing the status of the shared data table (use prohibition flag, etc.) - Shared area access subroutine - User program (application − tion task) ・In the event of an error, expand the data table from the electronic disk file to the inter-process shared area or recovery task ・Electronic disk file as a buffer in the inter-process shared area

Claims (1)

[Claims] (1) A method of using a shared data area in a data processing system, in which data processing is performed with exclusive control among multiple processes for any shared data area existing on main memory, and when a program error occurs, A method of using a shared data area characterized by automatic recovery.