Optimal static scheduling of real-time tasks on distributed time-triggered networked systems

Abstract

Mixed-criticality and high availability distributed systems, like those on large industrial deployments, strongly rely on deterministic communication in order to guarantee the realtime behavior. The time-triggered paradigm-as in TTEthernet-guarantees the deterministic delivery of messages with fixed latency and limited jitter. We look closely at industrial deployments in which production as well as consumption of messages is carried out within software tasks running on distributed embedded nodes (i.e. end-systems). We present an approach to minimize the end-to-end latency of such tasks, respecting their precedence constraints as well as the scheduled communication in an underlying switched TTEthernet network. The approach is based on and validated by a large industrial use-case for which we analyze a test bed implementing our solution.