Game g = new Game();

I assume this is only interesting for a very limited crowd. Still, it is worth mentioning:

ImageMagick may behave as a complete (meaning 99%) CPU resource hog, if several convert processes are running at the same time, as described by several users in the forums.

What worked for me: disabling IM’s internal threading. Sounds weird, but apparently there are some issues (especially?/only?) on RHEL/CentOS machines.

Build with configure –disable-openmp, and several parallel processes did not stall the CPU any longer.