System software strongly relies on the availability of static as well as dynamic adaptation techniques. With Aspect-Oriented Programming (AOP) it is now possible to adapt even policy-like crosscutting concerns in the implementation of system software. While this is straightforward in the static case, dynamic adaptation of crosscutting concerns requires an expensive dynamic aspect weaving infrastructure. Furthermore, the relation between static and dynamic aspects is widely unexplored.

In this paper we present our experiences with static and dynamic adaptation of crosscutting concerns in the embedded operating system eCos. The work is based on the novel "single language approach", which allows us to configure the binding time of aspects, and a "family-based dynamic weaver infrastructure", which reduces the resource consumption needed for dynamic AOP by tailoring the run time system. In our prototype implementation all this has been integrated into an environment, which allows us to "play" with the binding time of aspects and supported dynamic weaver features. Thus, we can now answer questions about the resource consumption of these adaptation techniques and the relationship of static and dynamic aspects in general.