Distributed Adaptation of Dining Philosophers

Abstract. Adaptation of a component-based system can be achieved in the coordination modelling language Paradigm through the special component McPal. McPal regulates the propagation of new behaviour and guides the changes in the components and in their coordination. Here we show how McPal may delegate part of its control to local adaptation managers, created on-the-fly, allowing for distribution of the adaptation indeed. We illustrate the approach for the well-known example of the dining philosophers problem, by modelling the migration from a deadlock-prone solution to a deadlock-free starvation-free solution without any system quiescence. The adaptation goes through various stages, exhibiting shifting control among McPal and its helpers, and changing degrees of orchestrated and choreographic collaboration.

A White Box Perspective on Behavioural Adaptation

We present a white-box conceptual framework for adaptation developed in the context of the EU Project ASCENS coordinated by Martin Wirsing. We called it CoDa, for Control Data Adaptation, since it is based on the notion of control data. CoDa promotes a neat separation between application and adaptation logic through a clear identification of the set of data that is relevant for the latter. The framework provides an original perspective from which we survey a representative set of approaches to adaptation, ranging from programming languages and paradigms to computational models and architectural solutions