JPH01226032A - Data saving/reconstituting system at check point restart - Google Patents

Abstract

PURPOSE:To reduce a file space for receding a data space and to reduce overhead by saving/reconstituting only data specifying backup attribution at the time of saving/reconstituting a user data space in check point restart. CONSTITUTION:A backup data control table in a load module 25 outputted by a linker 22 is referred on a check point at the time of executing restart and backup data are receded to a backup data storing file 4. At the time of reexecution, the backup data are restored from the file 4 and restarted. Since only the data specifying backup attribution are saved/reconstituted in the saving/ reconstituting data of the user data space at the time of check point restart, the file space for receding the user data space can be miniaturized and overhead based upon saving/reconstituting can be reduced.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a checkpoint restart method.
Second, it relates to a method for saving and restoring user data space in checkpoint restart.

[Conventional technology]

Conventionally, in the user data space save/restore method in checkpoint restart, the entire user data space is saved/restored.

[Problem to be solved by the invention]

In the conventional method for saving and restoring user data space in checkpoint restart, the entire user data space was saved and restored, which required a huge file sweep to save the user data space, resulting in the overhead of saving and restoring. The disadvantage is that it is large.

[Means to solve the problem]

The data backup/restoration method in checkpoint restart according to the present invention includes a specification means for specifying backup data to be saved at checkpoints, and a buffer data for backup data specified by the specification means at the checkpoint. It consists of a saving means for saving to a storage file, and a means for restoring from the backup data t-pa, qua, f data storage file saved by the saving means.

〔Example〕

Hereinafter, two embodiments of the present invention will be explained with reference to the drawings. Referring to FIG. Pack the evacuated backup data and save it to the data storage file 4
and means 3 for restoring from.

Hereinafter, as means 1 for specifying backup data, a case will be specifically explained using an example in which the pa, qua, and f attributes are specified as data definitions on the source program.

FIG. 2 shows an overview of the processing by the linker 22 and controller 21 in that case. The compiler 21 translates backup data 23 written in one source program,
Backup data control information is output to the object module 24. The linker 22 inputs the backup data control information output by the compiler 21 from the object module 24 and outputs the backup data control table to the load module 25.

Next, the compiler 21. Linker 22. The specific processing method for checkpoint restart is shown in Figure 3.
This will be explained with reference to FIGS. 4, 5, and 6.

At the time of translation, if the backup attribute is specified in the data definition description (see Figure 3), the compiler 21 will match the address storage area of the backup data and the data lengths of the backup data, such as the address storage area and the data length of the data. It outputs to the object module 24 the control data that has been set and reference information to the backup data such that the definition address of the backup data is set in the address storage area of the backup data at the time of linking (see FIG. 4).

After allocating the backup data to the user data space, the linker 22 sets the allocated address in the address storage area of the backup data by resolving references to the backup data, and stores the backup data along with the backup data length. Register in the data control table. When all inputs to the object module are completed, the number of backup data entries is set in the backup data control table and output to the load module 25 (see FIG. 5).

During execution, at a checkpoint, the backup data is saved to the backup data storage file 4 by referring to the backup data control table in the load module 25 output by the linker 22, and when re-executed, the backup data storage file 4 is saved. Restore the backup data and restart (see Figure 6).

〔Effect of the invention〕

As explained above, in the present invention, when saving and restoring the user data space during checkpoint restart, by saving and restoring only data with backup attributes specified, the file space for saving the user data space is saved. This has the effect of minimizing the overhead caused by saving and restoring.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of an embodiment of the present invention. Figure 2 is a diagram showing the flow of processing by the linker and compiler when specifying backup data on a source program, Figure 3 is a diagram showing an example of backup data definition in a source program, and Figure 4 is a diagram showing an example of backup data definition in a source program. Figure 5 shows backup data control information in the object module.
The figure shows the backup data control table in the load module, and FIG. 6 shows the flow of checkpoint restart. 1... Backup data designating means, 2... Backup data saving means, 3... Backup data restoring means, 4... Guk-a-gg data storage file. 21... Compiler, 22... Linker, 23...
Source program, 24...object module. 25...Load module. Figure 1 Figure 3 Figure 4

Claims (1)

[Claims] 1. A specifying means for specifying data to be saved at a checkpoint; a saving means for saving data specified by the specifying means to a data storage file at the checkpoint; A method for saving and restoring data in a checkpoint restart, comprising means for restoring from a data storage file.