<div dir="ltr">Hi,<br><div><br></div><div>I'm running a problem where at some point SCIP seems to hang, or at least, it stops logging. This is the output I get from it until that happens:</div><div><br></div><div><span style="font-family:monospace"><span style="color:rgb(0,0,0)">feasible solution found by trivial heuristic after 0.0 seconds, objective value 0.000000e+00
</span><br>presolving:
<br>(round 1, fast) 6 del vars, 9 del conss, 0 add conss, 96 chg bounds, 0 chg sides, 0 chg coeffs, 0 upgd conss, 86 impls, 148 clqs
<br>(round 2, exhaustive) 6 del vars, 92 del conss, 0 add conss, 96 chg bounds, 83 chg sides, 1 chg coeffs, 0 upgd conss, 86 impls, 148 clqs
<br>(round 3, exhaustive) 6 del vars, 92 del conss, 0 add conss, 96 chg bounds, 83 chg sides, 1 chg coeffs, 539 upgd conss, 86 impls, 148 clqs
<br> (0.0s) probing cycle finished: starting next cycle
<br>(round 4, exhaustive) 6 del vars, 92 del conss, 0 add conss, 177 chg bounds, 83 chg sides, 1 chg coeffs, 539 upgd conss, 1028 impls, 247 clqs
<br>(round 5, fast) 6 del vars, 92 del conss, 0 add conss, 177 chg bounds, 83 chg sides, 27 chg coeffs, 539 upgd conss, 1028 impls, 247 clqs
<br> (0.0s) probing: 108/148 (73.0%) - 0 fixings, 0 aggregations, 975 implications, 82 bound changes
<br> (0.0s) probing aborted: 50/50 successive totally useless probings
<br> (0.0s) symmetry computation started: requiring (bin +, int -, cont +), (fixed: bin -, int +, cont -)
<br> (0.0s) no symmetry present
<br>presolving (6 rounds: 6 fast, 4 medium, 4 exhaustive):
<br> 6 deleted vars, 92 deleted constraints, 0 added constraints, 178 tightened bounds, 0 added holes, 83 changed sides, 27 changed coefficients
<br> 1068 implications, 247 cliques
<br>presolved problem has 421 variables (148 bin, 0 int, 0 impl, 273 cont) and 837 constraints
<br> 193 constraints of type <varbound>
<br> 148 constraints of type <setppc>
<br> 298 constraints of type <linear>
<br> 198 constraints of type <logicor>
<br>Presolving Time: 0.02
<br>transformed 1/1 original solutions to the transformed problem space
<br>
<br> time | node | left |LP iter|LP it/n|mem/heur|mdpt |vars |cons |rows |cuts |sepa|confs|strbr| dualbound | primalbound | gap | compl. <br> 0.0s| 1 | 0 | 398 | - | 6511k | 0 | 421 | 851 | 836 | 0 | 0 | 13 | 0 | 7.631347e-02 | 0.000000e+00 | Inf | unknown
<br> 0.0s| 1 | 0 | 398 | - | 6521k | 0 | 421 | 851 | 836 | 0 | 0 | 13 | 0 | 7.631347e-02 | 0.000000e+00 | Inf | unknown
<br> 0.0s| 1 | 0 | 399 | - | 6637k | 0 | 421 | 851 | 837 | 1 | 1 | 13 | 0 | 7.466223e-02 | 0.000000e+00 | Inf | unknown
<br> 0.0s| 1 | 0 | 414 | - | 6782k | 0 | 421 | 851 | 838 | 2 | 2 | 13 | 0 | 7.388510e-02 | 0.000000e+00 | Inf | unknown
<br> 0.1s| 1 | 0 | 424 | - | 6936k | 0 | 421 | 851 | 842 | 6 | 3 | 13 | 0 | 6.982341e-02 | 0.000000e+00 | Inf | unknown
<br> 0.1s| 1 | 0 | 433 | - | 7114k | 0 | 421 | 851 | 845 | 9 | 4 | 13 | 0 | 6.814827e-02 | 0.000000e+00 | Inf | unknown
<br> 0.1s| 1 | 0 | 435 | - | 7273k | 0 | 421 | 851 | 846 | 10 | 5 | 13 | 0 | 6.814318e-02 | 0.000000e+00 | Inf | unknown
<br> 0.1s| 1 | 0 | 442 | - | 7418k | 0 | 421 | 851 | 847 | 11 | 6 | 13 | 0 | 6.780902e-02 | 0.000000e+00 | Inf | unknown
<br> 0.1s| 1 | 0 | 449 | - | 7686k | 0 | 421 | 851 | 851 | 15 | 7 | 13 | 0 | 6.745065e-02 | 0.000000e+00 | Inf | unknown
<br> 0.1s| 1 | 0 | 477 | - | 7902k | 0 | 421 | 851 | 853 | 17 | 8 | 13 | 0 | 6.700544e-02 | 0.000000e+00 | Inf | unknown
<br> 0.2s| 1 | 0 | 485 | - | 8009k | 0 | 421 | 852 | 855 | 19 | 9 | 14 | 0 | 6.606474e-02 | 0.000000e+00 | Inf | unknown
<br> 0.2s| 1 | 0 | 501 | - | 8476k | 0 | 421 | 852 | 857 | 21 | 10 | 14 | 0 | 6.543249e-02 | 0.000000e+00 | Inf | unknown
<br> 0.2s| 1 | 0 | 561 | - | 8569k | 0 | 421 | 852 | 859 | 23 | 11 | 14 | 0 | 6.433780e-02 | 0.000000e+00 | Inf | unknown
<br> 0.2s| 1 | 0 | 584 | - | 8751k | 0 | 421 | 853 | 860 | 24 | 12 | 15 | 0 | 6.388945e-02 | 0.000000e+00 | Inf | unknown
<br> 0.2s| 1 | 0 | 585 | - | 8845k | 0 | 421 | 854 | 861 | 25 | 13 | 16 | 0 | 6.388368e-02 | 0.000000e+00 | Inf | unknown
<br> time | node | left |LP iter|LP it/n|mem/heur|mdpt |vars |cons |rows |cuts |sepa|confs|strbr| dualbound | primalbound | gap | compl. <br> 0.2s| 1 | 0 | 600 | - | 9406k | 0 | 421 | 854 | 862 | 26 | 14 | 16 | 0 | 6.351136e-02 | 0.000000e+00 | Inf | unknown
<br> 0.3s| 1 | 0 | 605 | - | 9499k | 0 | 421 | 854 | 862 | 27 | 15 | 16 | 0 | 6.347853e-02 | 0.000000e+00 | Inf | unknown
<br> 0.3s| 1 | 0 | 611 | - | 9499k | 0 | 421 | 854 | 865 | 30 | 16 | 16 | 0 | 6.329991e-02 | 0.000000e+00 | Inf | unknown
<br> 0.4s| 1 | 2 | 1077 | - | 9614k | 0 | 421 | 854 | 865 | 30 | 18 | 16 | 26 | 6.258119e-02 | 0.000000e+00 | Inf | unknown<br>
<br></span></div><div>I've run it with a debugger, but given it is compiled without debugging symbols, I can only see that it is somewhere inside <span style="color:rgb(0,0,0);font-family:monospace">SCIPsolve.</span><span style="font-family:monospace"><br></span></div><div><span style="color:rgb(0,0,0);font-family:monospace"><br></span></div><div>I can dig deeper, but would first like to ask if this behaviour could be normal.<span style="color:rgb(0,0,0);font-family:monospace"><br></span></div><div><br></div><div>Thanks</div><div>Marco</div><span style="font-family:monospace"><br></span></div>