2.12. Unloading Control Groups
Warning
The
cgclear
command destroys all cgroups in all hierarchies. If you do not have these hierarchies stored in a configuration file, you will not be able to readily reconstruct them.
To clear an entire cgroup file system, use the
cgclear
command.
All tasks in the cgroup are reallocated to the root node of the hierarchies, all cgroups are removed, and the file system itself is unmounted from the system, destroying all previously mounted hierarchies. Finally, the directory where the cgroup file system was mounted is removed.
Note
Using the
mount
command to create cgroups (as opposed to creating them using the cgconfig
service) results in the creation of an entry in the /etc/mtab
file (the mounted file systems table). This change is also reflected in the /proc/mounts
file. However, the unloading of cgroups with the cgclear
command, along with other cgconfig commands, uses a direct kernel interface which does not reflect its changes into the /etc/mtab
file and only writes the new information into the /proc/mounts
file. After unloading cgroups with the cgclear
command, the unmounted cgroups can still be visible in the /etc/mtab
file, and, consequently, displayed when the mount
command is executed. Refer to the /proc/mounts
file for an accurate listing of all mounted cgroups.