Towards a Time-Composable Operating SystemReliable Software Technologies – Ada-Europe 2013

Compositional approaches to the qualification of hard real-time systems rest on the premise that the individual units of development can be incrementally composed preserving the timing behaviour they had in isolation. In practice, however, the assumption of time composability is often wavering due to the inter-dependences stemming from inherent nature of hardware and software. The operating system, mediator between the applications and the underlying hardware, plays a critical role in enabling time composability. This paper discusses the challenges faced in the implementation of a truly time-composable operating system based on ORK+, a Ravenscar-compliant real-time kernel.