On Fri, Jun 24, 2022 at 01:40:14PM +0300, Vasily Averin wrote: > Btw could you please explain why memory cgroups have MEM_CGROUP_ID_MAX limit > Why it is required at all and why it was set to USHRT_MAX? I believe that > in the future it may be really reachable: IIRC, one reason is 2B * nr_swap_pages of memory overhead (in swap_cgroup_swapon()) that's ~0.05% of swap space occupied additionally in RAM (fortunately swap needn't cover whole RAM). HTH, Michal