On Wed 01-06-22 11:15:43, Michal Koutny wrote: > On Wed, Jun 01, 2022 at 06:43:27AM +0300, Vasily Averin <vvs@xxxxxxxxxx> wrote: > > CT-901 /# cat /sys/fs/cgroup/memory/cgroup.subgroups_limit > > 512 > > CT-901 /# echo 3333 > /sys/fs/cgroup/memory/cgroup.subgroups_limit > > -bash: echo: write error: Operation not permitted > > CT-901 /# echo 333 > /sys/fs/cgroup/memory/cgroup.subgroups_limit > > -bash: echo: write error: Operation not permitted > > > > I doubt this way can be accepted in upstream, however for OpenVz > > something like this it is mandatory because it much better > > than nothing. > > Is this customization of yours something like cgroup.max.descendants on > the unified (v2) hierarchy? (Just curious.) > > (It can be made inaccessible from within the subtree either with cgroup > ns or good old FS permissions.) So we already do have a limit to prevent somebody from running away with the number of cgroups. Nice! I was not aware of that and I guess this looks like the right thing to do. So do we need more control and accounting that this? -- Michal Hocko SUSE Labs