Failure handling for transaction hierarchies

Previously, failure recovery mechanisms have been developed separately for nested transactions and for transactional workflows specified as “flat” flow graphs. The paper develops unified techniques for complex business processes modeled as cooperative transaction hierarchies. Multiple cooperative transaction hierarchies often have operational dependencies, thus a failure occurring in one transaction hierarchy may need to be transferred to another. The existing transaction models do not support failure handling across transaction hierarchies. The authors introduce the notion of transaction execution history tree which allows one to develop a unified hierarchical failure recovery mechanism applicable to both nested and flat transaction structures. They also develop a cross-hierarchy undo mechanism for determining failure scopes and supporting backward and forward failure recovery over multiple transaction hierarchies. These mechanisms form a structured and unified approach for handling failures in flat transactional workflows, along a transaction hierarchy, and across transaction hierarchies