Research On Workflow Model Verification And Data Access Conflict Analyze

Workflow is one of the important supporting techniques in CSCW. It facilitates people's cooperation by modeling, executing and managing processes to achieve their business goals. After a workflow model is built, the question of model verification and workflow concurrency is to be solved. To verify the semantic and structural correctness, a graph reduction method is introduced in this paper, combined with data flow analyze method, we complete a model verification tool. When multiple workflow instances execute in parallel, they might have some constraint relationships because some tasks of the instances might share the same data objects. This will cause serious problems of inconsistency in data access. This paper extends the Structured Workflow Definition Language (SWDL). By using set constraint systems, all possible conflict-causing tasks in the workflow and among the instances are analyzed and the conflicted task set of the data sources is generated. Based on that, the subset of the related tasks and the dynamic task constraints are generated, ensuring the temporary transaction among the instances of the task subset which might lead to data conflict when executing. This paper provides a flexible algorithm for as many as possible instances of tasks to run concurrently while ensuring the correctness of the workflow instances so that the performance of the workflow system is improved. An experiment proves the validity of this algorithm is discussed.