Dynamic Adaptation with Distributed Control in Paradigm
S. Andova, L.P.J. Groenewegen and E.P. de Vink

Adaptation of a component-based system can be achieved in the coordination
modeling 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 modeling migration
from a deadlock-prone solution to a deadlock-free and starvation-free solution
without any system quiescence. The system migration goes through various
stages, exhibiting a shift of control among McPal and its helpers, and
changing degrees of orchestrated and choreographic collaboration. The
distributed system adaptation is formally verified using the mCRL2 model
checker.