ParaXpress: an experimental extension of the FICO Xpress-Optimizer to solve hard MIPs on supercomputers. (English) Zbl 1397.90285

Summary: The Ubiquity Generator ({\mathsf {UG}}) is a general framework for the external parallelization of mixed integer programming (MIP) solvers. In this paper, we present {\mathsf{ParaXpress}}, a distributed memory parallelization of the powerful commercial MIP solver {\mathsf{FICO Xpress}}. Besides sheer performance, an important feature of {\mathsf{Xpress}} is that it provides an internal parallelization for shared memory systems. When aiming for a best possible performance of {\mathsf{ParaXpress}} on a supercomputer, the question arises how to balance the internal {\mathsf{Xpress}} parallelization and the external parallelization by {\mathsf{UG}} against each other. We provide computational experiments to address this question and we show computational results for running {\mathsf{ParaXpress}} on a Top500 supercomputer, using up to 43,344 cores in parallel.


90C11 Mixed integer programming
68M14 Distributed systems
65K05 Numerical mathematical programming methods
Full Text: DOI


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