Flexible Compensation of Workflow Processes

This paper addresses specification and implementation issues of workflow process compensation. The main consideration is to reduce the number of workflow activities that have to be compensated and re-executed when a failure occurs, as both can be very expensive. The main contributions of the paper are two-fold. First, we propose a flexible mechanism for specifying the compensation scope of a workflow process, based on a detailed analysis of dependencies between workflow activities. Second, we develop a novel implementation strategy that supports engine-based lazy compensation to further avoid unnecessary compensation efforts that are impossible to avoid at specification time. The proposed techniques are simple to implement, but also have the potential of significantly reducing compensation overhead.