Comment by deepsun

Linux can, and does, prevent a program to claim any new memory. Like literally malloc() returns null. How program reacts to that is up to the program.

Also I know linux has `cgroup_enable=memory` setting in /etc/default/grub, that's for Docker/K8S to be able to watch over containers RAM. It's not enabled by default as it slows down OS a little. Don't know if it's related to my first point.