Cmake not using all cores

Hi ! Lately I got an interesting issue while building the iso.

From the documentation, I’m trying to build the 1.3 equuleus in a docker container. The build is indeed working, but take a really long time. I’ve found that the make command is only using 100% of one core, when the container has 6 cores allowed.

I’ve tried to do ‘make iso -j 6’, without success.

Did anyone experienced this issue ? Any clue ?