Instructions for enabling the memory cgroup on Ubuntu 18 and 19 involve adding cgroup_enable=cpuset cgroup_enable=memory cgroup_memory=1 to /boot/firmware/nobtcmd.txt and restarting. After rebooting, grep mem /proc/cgroups should show it as enabled.
I find that on Ubuntu 20.04 the above instructions are not working for me, and Kubernetes continues to error [ERROR SystemVerification]: missing cgroups: memory. Any suggestions?
I was able to get this working by appending
cgroup_enable=cpuset cgroup_enable=memory cgroup_memory=1to the file/boot/firmware/cmdline.txt. Changes made to/boot/firmware/nobtcmd.txtin Ubuntu 20.04 appear to be ignored (there's a note in config.txt about cmdline=nobtcmd.txt being deprecated in favour of include commands).