How to limit process RAM by PID?

Question

linux

I heard about cgroup but did not find a command anywhere to limit the memory of a process.

Answer 1

You can try changing the RAM limit in the limits of the shell instance you are running the program from... see:

$ ulimit -Sm
unlimited

This requires LXC containers.
Are you ready to take such a complicated path for such a simple goal?
Perhaps something will tell you the translation of a whole series of articles directly from the author of LXC: LXC 1.0

Answer 2

You need CGroups.
ulimit works fine and doesn't really work.

Answer 3

A couple of links on the topic about modern ways of manipulating groups in different distributions:
https://wiki.archlinux.org/index.php/Cgroups
https://www.digitalocean.com/community/tutorials/h...
Hardcore way with manual adding a group (memory:/test), limiting the memory in it (one megabyte) and moving the process ($PID) into it:

# mkdir /sys/fs/cgroup/memory/test
# echo 1048576 > /sys/fs/cgroup/memory/test/memory.limit_in_bytes
# echo $PID >  /sys/fs/cgroup/memory/test/tasks