Configuration is unsuitable for single core machines

[david-perez]

judgedaemon.conf contains:

https://github.com/DOMjudge/domjudge-packaging/blob/c566fa91ca5018fccd43f15a1b4b80db9f5125e4/docker-contributor/supervisor/judgedaemon.conf#L3-L3

So supervisor goes ahead and starts 2 judgehosts, domjudge-contributor-0 and domjudge-contributor-1.

This configuration is unsuitable for running domjudge in single core machines. In a single core machine, if a judging is routed to domjudge-contributor-1, the daemon id 1 is eventually sent to rungard.c in the cpuset option. runguard.c performs a check to ensure cpuset >= 0 && cpuset < nproc, and crashes the judgehost with Running compile.sh caused an error/crash: /domjudge/bin/runguard: processor ID 1 given as cpuset, but only 1 cores configured.

Subsequent judgings will succeed since the judgehost gets disabled, but I was thoroughly confused.

I'm unfamiliar with how supervisor works, but ideally numprocs would be templated in from somewhere that caps it to the actual number of cores on the host.

[nickygerritsen]

We should make this an option with default 2 that you can override