Model theads value

[llex333]

Hi, community.

I try to understand how threads value of model working. i do several tests and see no difference between values -1,0 or others. If python-mip use Cbc solver, does it mean, that it can use not only one core for solving problem? Cause from side i see that using only one core, when i have much more is not optimal.

[sebheger]

See #311 and #253. There are several issues around that problem.