Dynamic Restructuring of Transactional Workflow Activities: A Practical Implementation Method

Abstract

We describe a practical method to implement the dynamic restructuring of distributed transactional activities with several main advantages. First, it guarantees the correctness of dynamic restructuring operations as well as that of ongoing transactional activities. Second, it is general enough to accommodate a wide range of workflow activities' dynamic restructuring requirements. Third, it facilitates the deployment of dynamic restructuring operations on production systems. Our method combines adaptors, microprotocols, and incremental specialization, building modularly on the system components (e.g., RTF [1], OCP [28], MARS [4]) that we previously developed to support distributed extended transaction processing [19]. A prototype implementation based on this method is built on top of Transarc Encina, a commercial online transaction processing (OLTP) monitor. To our knowledge, this is the first implementation of dynamic restructuring on top of commercial OLTP systems.