Configurable hybridkernel for embedded real-time systems

When designing a kernel for an operating system the developer has to choose between an microkernel or monolithic kernel approach. Bases for the decision is mostly the tradeoff between security and performance. Depending on application demands and on the available hardware a microkernel or a monolithic kernel approach or sornething between is desired. In this paper we present a hybrid kernel for embedded real-time systems which can be configured to the application demands in an easy way. To realize the hybrid kernel we present a technique to guarantee memory access in O(l) with virtual memory. With our approach the same codebase can be used for system services to be placed either in userspace or in kernelspace.