Research On YH-SUPE-based Component Debugging Technology Of Parallel Discrete Event Simulation

Component-oriented debugging technique is an effective approach for detecting errors, which not only has great influence for developing the efficiency of components, but also has great significance for improving the reliability of components. The current developing environment for parallel simulation has not provided an individual debugging function for the component of PDES. Therefore, the debugging codes always need to be hand-coding, and the executive process of the simulation engine is cared about excessively, which does not facilitate to concentrate on the executive process for detecting components. Accordingly, a study of YH-SUPE-based component debugging technique of PDES has become an important issue.According to the demand of componential development for PDES, based on the characteristics of YH-SUPE discussed, the key technologies of YH-SUPE-based component debugging are analyzed thoroughly in the paper. Major works and innovations are as follow:1) The current exist developing environments for parallel simulation have not provided an individual debugging function for the component of PDES directly. Therefore, the debugging codes always need to be hand-coding. To resolve this problem, the paper proposes a generating technique automatically for debugging code of components based on YH-SUPE modeling framework. This technique provides a reused assistant debugging component lib which is used to assemble to entity with the component needed to be debugged. Then, the entity is inserted into the main function template. As a result, the automatic plug-in for componential model is implemented, which provides efficient debugging approach for components of PDES.2) The event-schedule mechanism among the components of parallel discrete event simulation is implemented by simulation engine. This will lead user enter into the process code easily using some debugging operations, such as setting breakpoint and stepping into the code. This doesn't facilitate to detect the executive process of component. To resolve this problem, the paper put forward to an event-driven debugging approach for PDES component, which traces the next earliest event and generate debugging interrupt only in port handling function for this event. As a result, the process of simulation engine is hided, which improves the debugging efficiency of component.3) The simulation object instances in different nodes always run in a parallel way. This executive mode will lead the processing order of event in different nodes to be different, and then result in non-deterministic problem of reproducing errors in the process of running component. To resolve this problem, the paper presents a reappearing error approach based on enduring mechanism of YH-SUPE, which uses checkpoint technique to recover runtime state of the component and accord to the order recorded using enduring mechanism of YH-SUPE to schedule events. As a result, the executive process of component in the last two times is determined, which provides the assurance of locating the errors accurately in the process of the component debugging.Based on the results of above research, the paper designed and implemented a YH-SUPE-based component-oriented visual debugging framework for PDES. Using the framework, users could import YH-SUPE-based modeling component as well as generate debugging code automatically, and trace and debug the process of component efficiently. The test shows that this framework processes visual and easily grahic user interface, which is helpful for users to locate the errors accurately and quickly in the process when the component is running. It can meet the demand of debugging efficiently for components of parallel discrete event simulation.