Install libpam-cgroup by entering the following commands in the terminal:
sudo apt update sudo apt install libpam-cgroup
control and monitor control groups (PAM)
Control Groups (cgroups) provide a mechanism for aggregating/partitioning sets of tasks, and all their future children, into hierarchical groups with specialized behaviour. . libcgroup allows one to manipulate, control, administrate and monitor cgroups and the associated controllers. . This package contains the PAM module to move a user session into an existing cgroup by attempting to match uid and gid against the defined cgroup rules configuration.