Poster Abstract: An Optimizing Framework for Real-Time Scheduling

in Proceedings of 22nd IEEE Real-Time and Embedded Technology and Applications Symposium (RTAS 2016) (2016, April 12)

Scheduling is crucial in real-time applications. For any real-time system, the desired scheduling policy can be selected based on the scheduling problem itself and the underlying system constraints. This ... [more ▼]

Scheduling is crucial in real-time applications. For any real-time system, the desired scheduling policy can be selected based on the scheduling problem itself and the underlying system constraints. This paper discusses a novel optimization framework which automates the selection and configuration of the scheduling policy. The objective is to let designer state the permissible timing behavior of the system in a declarative manner. The system synthesis step involving both analysis and optimization then generates a scheduling solution which at runtime is enforced by the execution environment. [less ▲]

Towards a declarative modeling and execution framework for real-time systems

in ACM SIGBED Review (2016), 13(2), 30-33

Our work is a contribution towards addressing what Thomas Henziger called the grand challenge in embedded software design [5]: "offering high-level programming models that exposes the execution properties ... [more ▼]

Our work is a contribution towards addressing what Thomas Henziger called the grand challenge in embedded software design [5]: "offering high-level programming models that exposes the execution properties of a system in a way that permits the programmer to express desired reaction and execution requirements, permits the compiler and run-time systems to ensure that these requirements are satisfied". In the programming model we describe here, the developer states the permissible timing behavior of the system, a system synthesis step involving both analysis and optimization generates a scheduling solution which at run-time is enforced by the execution environment. With respect to the synchronous programming models, our approach implements a weaker version of time-determinism, still providing a form of timing-predictability sufficient in many applications while remaining closer to mainstay software development practices. This approach is currently being implemented and experimented in the CPAL language development tools and associated runtime environment. [less ▲]

Lean Model-Driven Development through Model-Interpretation: the CPAL design flow

Scientific Conference (2016, January 27)

We introduce a novel Model-Driven Development (MDD) flow which aims at more simplicity, more intuitive programming, quicker turnaround time and real-time predictability by leveraging the use of model ... [more ▼]

We introduce a novel Model-Driven Development (MDD) flow which aims at more simplicity, more intuitive programming, quicker turnaround time and real-time predictability by leveraging the use of model-interpretation and providing the language abstractions needed to argue about the timing correctness on a high-level. The MDD flow is built around a language called Cyber-Physical Action Language (CPAL). CPAL serves to describe both the functional behaviour of activities (i.e., the code of the function itself) as well as the functional architecture of the system (i.e., the set of functions, how they are activated, and the data flows among the functions). CPAL is meant to support two use-cases. Firstly, CPAL is a development and design space exploration environment for CPS with main features being the formal description, the editing, graphical representation and simulation of CPS models. Secondly, CPAL is a real-time execution platform. The vision behind CPAL is that a model is executed and verified in simulation mode on a workstation and the same model can be later run on an embedded board with a timing-equivalent run-time time behaviour. [less ▲]

Using CPAL to model and validate the timing behaviour of embedded systems

in 6th International Workshop on Analysis Tools and Methodologies for Embedded and Real-time Systems (WATERS) (2015, July 07)

This work presents a solution to the Formal Methods for Timing Verification (FMTV) Challenge 2015 using CPAL. CPAL stands for the Cyber-Physical Action Language and is a novel language to model, simulate ... [more ▼]

This work presents a solution to the Formal Methods for Timing Verification (FMTV) Challenge 2015 using CPAL. CPAL stands for the Cyber-Physical Action Language and is a novel language to model, simulate and verify cyber-physical systems as those described in the challenge. We believe that the complexity of the challenge mainly stems from the complex interactions of the tasks and processes composing the aerial video tracking system of the challenge. Using CPAL we have derived a complete and unambiguous description of the system that supports timing verification. The different sub-challenges were solved by timing-accurate simulation and/or schedulability analysis. Even though simulation does not provide firm guarantees on the worst-case behaviour, it helps the system designer solve scheduling problems and validate the solutions, where verification tools can not be applied directly due to the complexity of the model as in the 2015 FMTV challenge. [less ▲]