[Pkg-libvirt-maintainers] Bug#895360: virsh cpu-stats -> cgroup CPUACCT controller is not mounted

[Cédric Dufour - Idiap Research Institute]

Package: libvirt-daemon-system
Version: 3.0.0-4+deb9u3

Hello,

If one is to execute the following commands:
1. systemctl daemon-reload
2. service libvirtd restart
(which are likely to happen as part of regular system updates)

Subsequent virsh CPU statistics calls will fail with the following error messages:

# virsh cpu-stats <domain>
error: Failed to retrieve CPU statistics for domain '<domain>'
error: Requested operation is not valid: cgroup CPUACCT controller is not mounted

# virsh domstats --cpu-total <domain>
Domain: '<domain>'
[empty ouput]


Netsearching around, I stumbled on:
a. https://www.freedesktop.org/wiki/Software/systemd/ControlGroupInterface/
b. https://github.com/moby/moby/pull/20633 (similar Docker-related issue)

I can confirm the following workaround DOES solve the issue:

cat << EOF > /etc/systemd/system/libvirtd.service.d/cgroup-delegation.conf
[Service]
Delegate=yes
EOF


Would you consider adding this setting to the stock (Debian) libvirtd unit file ?

Thank you very much and best,

Cédric


Other ref: https://answers.launchpad.net/ubuntu/+question/665132

-- 
Cédric Dufour @ Idiap Research Institute