Hello, On Tue, May 28, 2024 at 04:37:12PM +0000, T.J. Mercier wrote: > The number of cgroups using a controller is an important metric since > kernel memory is used for each cgroup, and some kernel operations scale > with the number of cgroups for some controllers (memory, io). So users > have an interest in minimizing/tracking the number of them. I agree that this can be a useful metric but am not sure /proc/cgroups is the right place to put it. Its use of v1 controller names, listing of controllers that don't exist in v2 and the unnecessary column are rather ugly and unnecessary. Also, it isn't hierarchical which can make understanding where the css's are staying allocated difficult. In v2, cgroup.controllers and cgroup.subtree_control govern which controllers are available and enabled in the subtree. I think it would make sense to introduce something in a similar fashion. Can't think of a good name off the top of my head but add a cgroup. file which lists the controllers in the subtree along with the number of css's. Thanks. -- tejun
