Synthesising succinct strategies in safety games with an application to real-time scheduling

Abstract We introduce general techniques to compute, efficiently , succinct representations of winning strategies in safety and reachability games. Our techniques adapt the antichain framework to the setting of games, and rely on the notion of turn-based alternating simulation , which is used to formalise natural relations that exist between the states of those games in many applications. Then, we demonstrate the applicability of our approach by considering an important problem borrowed from the real-time scheduling community, i.e. the problem of finding a correct schedule(r) for a set of sporadic tasks upon a multiprocessor platform . We formalise this problem by means of a game whose number of states is exponential in the description of the task set, thereby making it a perfect candidate for our approach. We have implemented our algorithm and show experimentally that it scales better than classical solutions. To the best of our knowledge, this is the first attempt at implementing an exact feasibility test for this particular problem.

[1]  Julien Schmaltz,et al.  On Conformance Testing for Timed Systems , 2008, FORMATS.

[2]  Jean-François Raskin,et al.  Antichains: Alternative Algorithms for LTL Satisfiability and Model-Checking , 2008, TACAS.

[3]  Wang Yi,et al.  Uniprocessor Feasibility of Sporadic Tasks with Constrained Deadlines Is Strongly coNP-Complete , 2015, 2015 27th Euromicro Conference on Real-Time Systems.

[4]  Giorgio Delzanno,et al.  Covering sharing trees: a compact data structure for parameterized verification , 2004, International Journal on Software Tools for Technology Transfer.

[5]  Vincenzo Bonifaci,et al.  Feasibility Analysis of Sporadic Real-Time Multiprocessor Task Systems , 2010, ESA.

[6]  Thomas A. Henzinger,et al.  Alternating Refinement Relations , 1998, CONCUR.

[7]  Kim G. Larsen,et al.  Efficient On-the-Fly Algorithms for the Analysis of Timed Games , 2005, CONCUR.

[8]  Alan Burns,et al.  A survey of hard real-time scheduling for multiprocessor systems , 2011, CSUR.

[9]  Giorgio C. Buttazzo,et al.  Measuring the Performance of Schedulability Tests , 2005, Real-Time Systems.

[10]  Jean-François Raskin,et al.  Antichains and compositional algorithms for LTL synthesis , 2011, Formal Methods Syst. Des..

[11]  Nathalie Bertrand,et al.  A game approach to determinize timed automata , 2011, Formal Methods Syst. Des..

[12]  C. L. Bouton Nim, A Game with a Complete Mathematical Theory , 1901 .

[13]  David L. Dill,et al.  Timing Assumptions and Verification of Finite-State Concurrent Systems , 1989, Automatic Verification Methods for Finite State Systems.

[14]  Daniel Neider,et al.  Small Strategies for Safety Games , 2011, ATVA.

[15]  Jean-François Raskin,et al.  Antichain Algorithms for Finite Automata , 2010, TACAS.

[16]  A. Marchetti-Spaccamela,et al.  Feasibility Analysis of Sporadic Real-Time Multiprocessor Task Systems , 2010, Algorithmica.

[17]  Rajeev Alur,et al.  A Theory of Timed Automata , 1994, Theor. Comput. Sci..

[18]  Joël Goossens,et al.  Multiprocessor schedulability of arbitrary-deadline sporadic tasks: complexity and antichain algorithm , 2012, Real-Time Systems.

[19]  Theodore P. Baker,et al.  Brute-Force Determination of Multiprocessor Schedulability for Sets of Sporadic Hard-Deadline Tasks , 2007, OPODIS.