A First Implementation of ParaXpress: Combining Internal and External Parallelization to Solve MIPs on Supercomputers

  • Yuji Shinano
  • Timo BertholdEmail author
  • Stefan Heinz
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9725)


The Ubiquity Generator (UG) is a general framework for the external parallelization of mixed integer programming (MIP) solvers. It has been used to develop ParaSCIP, a distributed memory, massively parallel version of the open source solver SCIP, running on up to 80,000 cores. In this paper, we present a first implementation of ParaXpress, a distributed memory parallelization of the powerful commercial MIP solver FICO Xpress. Besides sheer performance, an important difference between SCIP and Xpress is that Xpress provides an internal parallelization for shared memory systems. When aiming for a best possible performance of ParaXpress on a supercomputer, the question arises how to balance the internal Xpress parallelization and the external parallelization by UG against each other. We provide computational experiments to address this question and we show preliminary computational results for running a first version of ParaXpress on 6,144 cores in parallel.


Mixed integer programming Distributed memory parallelization 


  1. 1.
    Achterberg, T.: Constraint Integer Programming. Ph.D. thesis, Technische Universität Berlin (2007)Google Scholar
  2. 2.
    Achterberg, T., Wunderling, R.: Mixed integer programming: Analyzing 12 years of progress. In: Jünger, M., Reinelt, G. (eds.) Facets of Combinatorial Optimization - Festschrift for Martin Grötschel, pp. 449–481. Springer, Heidelberg (2013)CrossRefGoogle Scholar
  3. 3.
    Bussieck, M.R., Ferris, M.C., Meeraus, A.: Grid-enabled optimization with GAMS. IJoC 21(3), 349–362 (2009)MathSciNetCrossRefzbMATHGoogle Scholar
  4. 4.
    Eckstein, J., Hart, W.E., Phillips, C.A.: Pebbl: an object-oriented framework for scalable parallel branch and bound. Math. Program. Comput. 7(4), 429–469 (2015). MathSciNetCrossRefzbMATHGoogle Scholar
  5. 5.
  6. 6.
    Laundy, R., Perregaard, M., Tavares, G., Tipi, H., Vazacopoulos, A.: Solving hard mixed-integer programming problems with Xpress-MP: a MIPLIB 2003 case study. INFORMS J. Comput. 21(2), 304–313 (2009)MathSciNetCrossRefzbMATHGoogle Scholar
  7. 7.
    Nemhauser, G.L., Wolsey, L.A.: Integer and combinatorial optimization. Wiley, New York (1988)CrossRefzbMATHGoogle Scholar
  8. 8.
    Shinano, Y., Achterberg, T., Berthold, T., Heinz, S., Koch, T., Winkler, M.: Solving hard MIPLIB2003 problems with ParaSCIP on supercomputers: An update. In: 2014 IEEE International Parallel Distributed Processing Symposium Workshops (IPDPSW), pp. 1552–1561, May 2014Google Scholar
  9. 9.
    Shinano, Y., Achterberg, T., Berthold, T., Heinz, S., Koch, T.: ParaSCIP - a parallel extension of SCIP. In: Bischof, C., Hegering, H.G., Nagel, W.E., Wittum, G. (eds.) Competence in High Performance Computing 2010, pp. 135–148. Springer, Heidelberg (2012)Google Scholar
  10. 10.
    Shinano, Y., Achterberg, T., Berthold, T., Heinz, S., Koch, T., Winkler, M.: Solving open MIP instances with ParaSCIP on supercomputers using up to 80,000 cores. In: Proceedings of 30th IEEE International Parallel & Distributed Processing Symposium, to appear (2016)Google Scholar
  11. 11.
    Shinano, Y., Achterberg, T., Fujie, T.: A dynamic load balancing mechanism for new ParaLEX. Proc. ICPADS 2008, 455–462 (2008)Google Scholar
  12. 12.
    Shinano, Y., Heinz, S., Vigerske, S., Winkler, M.: FiberSCIP - a shared memory parallelization of SCIP. Technical Report ZR 13–55, Zuse Institute Berlin (2013)Google Scholar
  13. 13.
    Sun, Y., Zheng, G., Jetley, P., Kalé, L.V.: ParSSSE: An adaptive parallel state space search engine. Parallel Process. Lett. 21(3), 319–338 (2011)MathSciNetCrossRefzbMATHGoogle Scholar
  14. 14.
    Xu, Y., Ralphs, T.K., Ladányi, L., Saltzman, M.: Alps version 1.5.2 (2015)Google Scholar

Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  1. 1.Zuse Institute BerlinBerlinGermany
  2. 2.Fair Isaac Germany GmbHBerlinGermany

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