# Gurobi uses 1 core on supercomputer node with 64 cores

I have installed Gurobi 9.1.1 on a supercomputer node with 64 Xeon processors. For the installation I used conda.

I access this node via ssh. When running "htop" I see that the process uses 1 core at 100% and very rare times (lets say 1% of the total time) it uses 1 or 2 extra cores for only a few seconds.

In fact, my laptop with Intel i5 runs the same process using all the cores and is 10 times faster than the "supercomputer".

I have asked the admin of the server if this situation may be the result of a configuration in the server. I am waiting for her answer.

What could be the reason for this situation?

• What parameters/configuration are you running? What version of gurobi etc. Some detail would help... Mar 18 at 23:23
• Just to be sure: This problem occurs in the branch-and-bound tree exploration phase? Do you use callbacks? Jun 25 at 10:41

m.setParam('Threads', 64)

import gurobipy as gb