Solving Hard MIPLIB2003 Problems with ParaSCIP on Supercomputers: An Update

Contemporary supercomputers can easily provide years of CPU time per wall-clock hour. One challenge of today´s software development is how to harness this vast computing power in order to solve really hard mixed-integer programming instances. In 2010, two out of six open MIPLIB2003 instances could be solved by ParaSCIP in more than ten consecutive runs, restarting from checkpointing files. The contribution of this paper is threefold: For the first time, we present computational results of single runs for those two instances. Secondly, we provide improved upper and lower bounds for all of the remaining four open MIPLIB2003 instances. Finally, we explain which new developments led to these results and discuss the current progress of ParaSCIP. Experiments were conducted on HLRN II, on HLRN III, and on the Titan supercomputer, using up to 35,200 cores.