$ systemctl status machine.slice ● machine.slice - Virtual Machine and Container Slice Loaded: loaded (/usr/lib/systemd/system/machine.slice; static; vendor preset: disabled) Active: active since Wed 2018-06-13 08:45:07 BST; 1 day 15h ago Docs: man:systemd.special(7) Tasks: 0 Memory: 717.0M CGroup: /machine.slice $ cd /sys/fs/cgroup/memory/machine.slice $ cat memory.usage_in_bytes 751915008 $ cat tasks $ cat cgroup.procs $
What does it mean, for the
machine.slice cgroup to be using 717MB, even though it is empty of processes/threads? Is it a kernel bug?
I can reproduce this simply by starting a VM with virt-manager, and then stopping it. If I repeat the cycle, the result is about the same - i.e. the system doesn't appear to be leaking these hundreds of megabytes.
$ uname -r 4.16.14-300.fc28.x86_64 $ rpm -q systemd libvirt-daemon systemd-238-8.git0e0aa59.fc28.x86_64 libvirt-daemon-4.1.0-2.fc28.x86_64