Abstract
Composability and compositionality are well recognised as key enablers in rigorous design and analysis of complex systems. We argue that existing work on these enablers, specific to real-time systems, has exclusively focussed on design and analysis of structural composition, by which we refer to composition of either separate software tasks or compositions thereof on a shared platform such as a processor. Though structural composition is common and likely the most useful such composition, we make the case of an altogether different kind of composition which we refer to as behavioural composition. As a specific example of behavioural composition, we discuss how to constructively build complex server algorithms, called Demand Bound Servers (DBS), by composing constituent simpler server algorithms, even hierarchically. As a result of such composition, we can build server algorithms to more tightly match the requirements of tasks they need to serve, which indeed is not possible with the simpler components themselves. This is an example of how new behaviour is emergent out of the composition. We remain curious if there are other such examples of behavioural composition of interest to real-time systems.
- H. Kopetz and G. Bauer, "The time-triggered architecture," Proceedings of the IEEE, vol. 91, no. 1, pp. 112--126, 2003.Google ScholarCross Ref
- A. Hansson, K. Goossens, M. Bekooij, and J. Huisken, "CoMPSoC: A template for composable and predictable multi-processor system on chips," ACM Trans. Design Autom. Electr. Syst., vol. 14, no. 1, 2009. Google ScholarDigital Library
- M. Spuri and G. C. Buttazzo, "Efficient Aperiodic Service Under Earliest Deadline Scheduling," in IEEE Real-Time Systems Symposium, IEEE Computer Society, 1994.Google Scholar
- R. Rajkumar, K. Juvva, A. Molano, and S. Oikawa, "Resource kernels: A resource-centric approach to real-time and multimedia systems," in In Proceedings of the SPIE/ACM Conference on Multimedia Computing and Networking, 1998.Google Scholar
- G. Lipari and S. K. Baruah, "Efficient scheduling of real-time multi-task applications in dynamic systems," in IEEE Real Time Technology and Applications Symposium, 2000. Google ScholarDigital Library
- R. Alur and D. L. Dill, "A theory of timed automata," Theor. Comput. Sci., vol. 126, no. 2, pp. 183--235, 1994. Google ScholarDigital Library
- I. Shin and I. Lee, "Periodic Resource Model for Compositional Real-Time Guarantees," in RTSS, pp. 2--13, IEEE Computer Society, 2003. Google ScholarDigital Library
- L. Thiele, S. Chakraborty, and M. Naedele, "Real-time calculus for scheduling hard real-time systems," in IEEE International Symposium on Circuits and Systems, vol. 4, pp. 101--104, 2000.Google Scholar
- A. Hamann, M. Jersak, K. Richter, and R. Ernst, "Design Space Exploration and System Optimization with SymTA/S-Symbolic Timing Analysis for Systems," in RTSS, pp. 469--478, IEEE Computer Society, 2004. Google ScholarDigital Library
- P. Kumar, J.-J. Chen, and L. Thiele, "Demand bound server: generalized resource reservation for hard real-time systems," in EMSOFT, pp. 233--242, ACM, 2011. Google ScholarDigital Library
- L. Abeni and G. C. Buttazzo, "Integrating Multimedia Applications in Hard Real-Time Systems," in IEEE Real-Time Systems Symposium, 1998. Google ScholarDigital Library
- T. M. Ghazalie and T. P. Baker, "Aperiodic servers in a deadline scheduling environment," Real-Time Systems, vol. 9, no. 1, 1995. Google ScholarDigital Library
- S. K. Baruah, A. K. Mok, and L. E. Rosier, "Preemptively scheduling hard-real-time sporadic tasks on one processor," in IEEE Real-Time Systems Symposium, 1990.Google Scholar
- F. Zhang and A. Burns, "Analysis of Hierarchical EDF Pre-emptive Scheduling," in RTSS, pp. 423--434, IEEE Computer Society, 2007. Google ScholarDigital Library
- J.-Y. L. Boudec and P. Thiran, Network Calculus: A Theory of Deterministic Queuing Systems for the Internet, vol. 2050 of Lecture Notes in Computer Science. Springer, 2001. Google ScholarDigital Library
Index Terms
- Behavioural composition constructively built server algorithms
Recommendations
Thrift Service Composition: Toward Extending BPEL
SCIOT '18: Proceedings of the international conference on smart cities and internet of thingsToday, there are more than 7 billion connected devices including resource-constrained devices which are capable of participating in service collaborations. Service Oriented Architecture (SOA) is prominent as a result of loose coupling and platform ...
QoS-Aware Service Composition: A Survey
ECOWS '10: Proceedings of the 2010 Eighth IEEE European Conference on Web ServicesService compositions build new services by orchestrating a set of existing services. In the Internet of Services there may be many functional similar services, but with different Quality of Service (QoS). Thus a significant research problem in service ...
Web service composition: a reality check
WISE'07: Proceedings of the 8th international conference on Web information systems engineeringAutomated web service composition is one of the major promises of service-oriented architecture, where services can be discovered and composed dynamically and automatically. To investigate the methods for composite web service construction, we conducted ...
Comments