Section: New Results

Scalability of Constraint Programming for Real-Time Scheduling

Participants : Dumitru Potop Butucaru, Robert de Simone.

Given two abstract modeling descriptions, one of a dataflow process network for the application, one of a block diagram structure for the computing platform and its interconnects, together with cost functions for the elementary computations and communications, one is bound to seek optimal mappings pairing the two. Amongst all the possible techniques, an obvious one consists in using general constraint solvers (real, integer, or boolean constraint programming, SMT solvers, CP solvers, etc.). Given the NP-hard nature of the problem, the issue here is to experimentally determine the empyrical complexity of various scheduling problems, and thus help in determining when solvers can be used for the resolution of scheduling problems.

In previous years we addressed this issue for ILP and SMT solvers. This year, we considered a Constraint Programming solver with dedicated support for modeling and solving real-time scheduling problems (IBM ILOG CPLEX CP Optimizer). The work was conducted in the framework of Bimael Iosif's student internship, and the writing of a paper is under way.