An Adaptive Transactional System - Framework and Service Synchronization

The characteristics of advanced applications vary a lot and the transaction concept must adapt to fulfil the varying transactional requirements. However, current transaction services do not support the required flexibility in a principled way. We believe that the need for transaction service flexibility can be supported through reflection, where the system is capable of inspecting and changing its own behaviour. The first part of this paper describes a framework for such a reflective transactional system, in which different transaction services can be deployed and modified, and from where a suitable transaction service can be chosen for the execution of a transaction. As concurrent transactions may request different transaction services, the framework allows concurrently active transaction services within the same environment. To ensure correctness when heterogeneous transaction services are concurrently active, a transaction service manager within this framework, provides, among other tasks, transaction service synchronization. The second part of the paper concentrates on service synchronization, and presents algorithms that demonstrate how correctness can be guaranteed when incompatible services are requested.