> This patchset finally implements the default unified hierarchy. The > goal is providing enough flexibility while enforcing stricter common > structure where appropriate to address the above listed issues. > > Controllers which aren't bound to other hierarchies are > automatically attached to the unified hierarchy, which is different in > that controllers are enabled explicitly for each subtree. > "cgroup.subtree_control" controls which controllers are enabled on the > child cgroups. Let's assume a hierarchy like the following. > > root - A - B - C > \ D > > root's "cgroup.subtree_control" determines which controllers are > enabled on A. A's on B. B's on C and D. This coincides with the > fact that controllers on the immediate sub-level are used to > distribute the resources of the parent. In fact, it's natural to > assume that resource control knobs of a child belong to its parent. > Enabling a controller in "cgroup.subtree_control" declares that > distribution of the respective resources of the cgroup will be > controlled. Note that this means that controller enable states are > shared among siblings. > > The default hierarchy has an extra restriction - only cgroups which > don't contain any task may have controllers enabled in > "cgroup.subtree_control". Combined with the other properties of the > default hierarchy, this guarantees that, from the view point of > controllers, tasks are only on the leaf cgroups. In other words, only > leaf csses may contain tasks. This rules out situations where child > cgroups compete against internal tasks of the parent. > Right after bootup: # mount -t cgroup -o __DEVEL__sane_behavior xxx /mnt # ls /mnt cgroup.controllers cgroup.procs cgroup.sane_behavior cgroup.subtree_control # cat /mnt/cgroup.controllers cpuset cpu cpuacct memory devices freezer net_cls blkio perf_event hugetlb I don't see any controller knobs... _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/containers
