this paper we describe the architecture and

When parallel processing became popular at the end of the eighties, it became evident that common operating systems were not able to deliver the pure performance of parallel hardware to parallel applications. Much processing power was wasted with complex system call mechanisms and sometimes vast resource consumptions of the operating system itself. Even micro-kernel based systems were often too slow, because these also relied on computing power consuming concepts like address space separation or virtual memory systems. Nevertheless, some applications required exactly those functionalities that others denied for performance reasons. Since this contradiction can hardly be solved within a single operating system, the PEACE operating system family[10] was developed at GMD-FIRST. The most simple family members were represented as highly efficient runtime libraries while the most complex members can be regarded as full fledged micro-kernel based operating systems. Family based systems can be implemented conveniently by means of object oriented programming paradigms. Thus the Peace operating system family has entirely been implemented in C++. Operating system services are implemented as classes and users can extend and specialize these system classes by means of inheritance mechanisms. In theory this scenario is sound and straight forward but in practice the conceptual advantages of object orientation are extremely hard to exploit without suitable object models and language-level support for object-oriented implementation techniques in distributed contexts.

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. Due to their potential degree of complexity, up- and downward scalable operating systems make configuration support reasonable, at least in a semi-automated style. If the need for dynamically adaptable family members is given, system support for applying configuration decisions at runtime is a must. But is the pure circumstance of dynamics in fact a good reason for applying high level, meta concepts, covering the needs for a broad range of configuration aspects of systems and applications in a single `fitting all' manner? In this paper, we present the adaption scheme Bald (Basic Adaption Layered on Decomposition), that tries to found a modest scheme for handling (dynamic) configuration, scalable and extensible to semantically richer schemes in a family-oriented sense. 1 Introduction People who design software for rather distinct products as household appliances, cars, trains or product lines are forced to re-invent the wheel for nearly every new (embedded) system cause they don't ...