Re: [libvirt-users] cgroup error starting domains

On Fri, Jun 07, 2013 at 01:07:01PM +0200, Matteo Bernardini wrote: [snip] Ok so here you've mounted all the cgroups controllers at the same place. This is really strongly recommended against. It is better to mount each controller separately at /sys/fs/cgroup/<controller name> and have /sys/fs/cgroup as a tmpfs. http://www.freedesktop.org/wiki/Software/systemd/PaxControlGroups eg to get something along the lines of: $ ls -l /sys/fs/cgroup/ total 0 drwxr-xr-x. 3 root root 0 Jun 3 09:41 blkio lrwxrwxrwx. 1 root root 11 Jun 3 09:41 cpu -> cpu,cpuacct lrwxrwxrwx. 1 root root 11 Jun 3 09:41 cpuacct -> cpu,cpuacct drwxr-xr-x. 3 root root 0 Jun 3 09:41 cpu,cpuacct drwxr-xr-x. 3 root root 0 Jun 3 09:41 cpuset drwxr-xr-x. 3 root root 0 Jun 3 09:41 devices drwxr-xr-x. 3 root root 0 Jun 3 09:41 freezer drwxr-xr-x. 3 root root 0 Jun 3 09:41 memory drwxr-xr-x. 2 root root 0 Jun 3 09:41 net_cls drwxr-xr-x. 2 root root 0 Jun 3 09:41 perf_event drwxr-xr-x. 4 root root 0 Jun 3 09:42 systemd $ grep cgroup /proc/mounts tmpfs /sys/fs/cgroup tmpfs rw,seclabel,nosuid,nodev,noexec,mode=755 0 0 cgroup /sys/fs/cgroup/systemd cgroup rw,nosuid,nodev,noexec,relatime,release_agent=/usr/lib/systemd/systemd-cgroups-agent,name=systemd 0 0 cgroup /sys/fs/cgroup/cpuset cgroup rw,nosuid,nodev,noexec,relatime,cpuset 0 0 cgroup /sys/fs/cgroup/cpu,cpuacct cgroup rw,nosuid,nodev,noexec,relatime,cpuacct,cpu 0 0 cgroup /sys/fs/cgroup/memory cgroup rw,nosuid,nodev,noexec,relatime,memory 0 0 cgroup /sys/fs/cgroup/devices cgroup rw,nosuid,nodev,noexec,relatime,devices 0 0 cgroup /sys/fs/cgroup/freezer cgroup rw,nosuid,nodev,noexec,relatime,freezer 0 0 cgroup /sys/fs/cgroup/net_cls cgroup rw,nosuid,nodev,noexec,relatime,net_cls 0 0 cgroup /sys/fs/cgroup/blkio cgroup rw,nosuid,nodev,noexec,relatime,blkio 0 0 cgroup /sys/fs/cgroup/perf_event cgroup rw,nosuid,nodev,noexec,relatime,perf_event 0 0 (obviously the 'system' mount point is not required if not using systemd). And this, together with your mount setup is what causes the problem. Here you have told libvirt to *only* use those 6 listed cgroups controllers, but because you've mounted all 9 controllers at the same mount point, it is impossible for libvirt to satisfy the config you requested. It can't use the 6 controllers you asked for, without also using the other 3 you have excluded in the config. Either comment out that cgroup_controllers setting (to let libvirt do auto-detection of mounts), or switch to using a separate mount per controller, or both. Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|