Hi Nico - Can you share the log of your optimization run?

Thanks!

Sure, I am adding a Screenshot here. But if needed, I can also send you the entire logfile. I marked the place, where a heuristic solution has been found according to the log. I also set GRB_IntParam_NoRelHeuristic to 0 as you suggested in your email.

Some of these don't apply to the log you shared, but what happens when you set all these parameters to 0?

MinRelNodes    Minimum relaxation heuristic control
PartitionPlace    Controls when the partition heuristic runs
PumpPasses    Feasibility pump heuristic control
RINS    RINS heuristic
SubMIPNodes    Nodes explored by sub-MIP heuristics
ZeroObjNodes    Zero objective heuristic control

I have tried that as well and still heuristics are shown in the log.

Hi,

With heuristics disabled, Gurobi spends no time actively looking for heuristic solutions. However, it could happen that Gurobi still encounters solutions as part of its solving process, even without devoting any additional meaningful work to finding them. These are reported as heuristic solutions.

Thanks,

Eli