Now I am using Or-Tools via the Java interface to solve a LP.

ModelBuilder model = new ModelBuilder();
ModelSolver solver = new ModelSolver("SCIP");

During the presolve process, the JVM exits with an error message: *

Process finished with exit code 132 (interrupted by signal 4: SIGILL)

*, see the first picture.

When I add the VM options -Xss8m, the LP is solved to optimality. However, the presolve process is still very long, see the second picture. When the problem instance changes, the VM options may become invalid. It should be changed to -Xss16m, or higher.

Does anyone has any suggestions to avoid the program break-out, when using this Or-Tools? Should I use a LP solver instead of the SCIP? What's more, the log output "

Deactivated symmetry handling methods, since SCIP was built without symmetry detector (SYM=none).

", can we improve the solving efficiency by addressing this issue?

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1 Answer 1


I guess the signal is sent when memory is exhausted. Now your problem only uses continuous variables. You do not need a MIP solver. You can use 'glop'.

  • $\begingroup$ Thank you. It works. I change the solvetype to GLOP, the optimal solution is found in 5 seconds. However, when the solverType is set to CLP, the result is "status = UNKNOWN_STATUS". A little confusing. $\endgroup$
    – Ying
    Commented Oct 29, 2023 at 8:47

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