Redundant System State Capture via Delayed Execution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods for acquiring data to investigate the cause of computer troubles incur overhead and delay in normal program processing, especially when dealing with large amounts of data, as they require periodic storage of system states before a trouble occurs.
Innovation Solution
A computer system with an active and redundant system operating in the same environment, where the redundant system processes with a delay and stores its state when a trouble is detected in the active system, allowing for data capture without interrupting normal processing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If data is acquired and stored at predetermined time intervals during normal program execution, then data indicating system state before trouble occurrence can be obtained, but overhead increases and normal program processing is delayed
Solution Approach 1:
The redundant system performs preliminary actions by executing the same program in advance with a time delay, so that when trouble occurs in the active system, the redundant system already has the required state data ready for immediate storage without needing to perform storage operations at predetermined intervals during normal execution
Solution Approach 2:
A redundant system is created as a copy of the active system, executing the same program with a time delay. This copy provides the required state data when trouble occurs, eliminating the need for periodic data storage operations in the active system and thus reducing overhead and processing delays
2Loss of information
If all images in main memory and files on external memory devices are stored, then complete troubleshooting data is obtained, but the amount of data to be stored increases significantly
Solution Approach 1:
Only the necessary state data from the redundant system is extracted and stored when trouble occurs, rather than continuously storing all possible data including all main memory images and external files. This extraction approach obtains sufficient troubleshooting information while minimizing the quantity of data handled
Data Source
AI summary
To make it possible to store a state immediately before occurrence of a trouble with little influence on normal program processing, separately from an active system in which a program operates, a redundant system is provided in which the same program as the program operates in the same execution environment as the active system. A delay execution control section gives the redundant system the same processing request as a processing request given to the active system, with a delay. When a trouble monitoring section detects a trouble of the active system, a state storage control section acquires data indicating a state of the redundant system and stores it in a state data storing section. Because the same program is executed with a delay in the redundant system having the same execution environment as the active system, a state of the redundant system at the time when the trouble occurs in the active system is equivalent to a state immediately before the occurrence of the trouble in the active system.