Results of the Second International Competition
of CSP and Max-CSP Solvers

In 2005, the first competition of CSP solvers was held alongside the second workshop on Constraint Propagation and Implementation (CPAI'05). For this edition, only instances involving constraints defined in extension were considered.
&rArr 15 CSP solvers proposed by 10 teams were entering the competition and run against a suite of 1064 instances (binary and non binary), time-out set to 10 minutes per instance.
&rArr See the results (time-out set to 10 minutes per instance).

In 2006, the second competition of CSP solvers was held alongside the third workshop on Constraint Propagation and Implementation (CPAI'06). For this second edition, instances involving constraints defined both in extension and in intention (i.e. by a predicate) were considered. Also, the global constraint allDifferent has been introduced.
&rArr 21 CSP solvers proposed by 12 teams were entering (the second round of) the competition and run against a suite of 3425 instances (both binary and non binary).
&rArr See the results (memory limited to 900MB - time-out set to 30 minutes per instance - total time of 343 CPU days).

Also, a second problem has been considered for the 2006 competition: Max-CSP. This was the first edition.
&rArr 9 Max-CSP solvers proposed by 5 teams were entering the competition and run against a suite of 1069 instances (binary and non binary).
&rArr See the results (memory limited to 900MB - time-out set to 40 minutes per instance - total time of 101 CPU days).

Concerning the 2006 edition, you can obtain;

• the description of the solvers submitted to the competition
• the XML format used to represent the instances
• the selected CSP instances in XML format
• some tools to parse and manipulate instances in XML format

On this web site, you will have the possibility to obtain some information about the instances, the solvers and of course the results of the 2006 competition. We hope that all this information will be useful to judge about the robustness and efficiency of the different proposed algorithms/solvers. Note that some documents describing some solvers will be made available soon. Also, we project to write in the near future a document containing a detailed analysis of the results.

In 2008, we should be able to organize the third competition of CSP solvers (the deadline for participating should be May 2008). It is important to note that the XML format used to represent (classical) CSP instances should remain the same. So, do not hesitate to project a future participation right now. Also, some new categories/problems might be proposed since the XML format should be soon extended to take into account:

• a core of global constraints,
• weighted CSP instances,

Finally, we'd like to thank the following people/institutions for turning the 2006 edition into a successful event:

• The members of the independent jury, Radoslaw Szymanek (EPFL - Lausanne), Djamal Habet (LSIS - Marseille) and Richard Ostrowski (LSIS - Marseille), who selected the final instances for the competition.
• Lucas Bordeaux (Microsoft) for providing the SMT instances.
• Rick Wallace (4C) for generating his Max-CSP instances.
• The CRIL (Centre de Recherche en Informatique de Lens) from the university of Artois for providing the cluster for the final evaluation.
• The Association for Constraint Programming (ACP) for financially supporting the event.
• All members of the organising committee.
• The contestants for participating: without them there would not have been a competition.

We hope that you will appreciate this modest (and obviously unperfect) contribution to the domain of Constraint Programming.