Dynamic reconfiguration of component-based real-time software

Increasing capabilities of modem microcontrollers greatly increase their applicability to more and more complex scenarios. However unstable and ever-changing environmental settings require embedded systems permanently to adapt to new situations. Dynamic reconfiguration provides a powerful mechanism to execute such adaptation strategies. The implementation of dynamic reconfiguration is still challenging for embedded real-time control software. Within earlier work we have presented our framework Adapt.NET for runtime adaption of component-based applications, including a runtime infrastructure for dynamic reconfiguration and monitoring, targeted for mobile and desktop environments. New experiments in our web-based remote laboratory - the Distributed Control Lab - require the reconfiguration to complete in bounded time. In the remote lab we use dynamic reconfiguration to adapt experiment control to failures in user control components. Within this paper we will analyze the timing behavior of the implemented dynamic reconfiguration algorithm in order to allow for predictable execution times. We describe how complex component-based real-time applications can be adapted to changing environmental conditions, continuously meeting all tasks deadlines during dynamic reconfiguration.