On Wed 09-08-17 15:06:34, wang Yu wrote: > Hello Johannes ,Michal,and Tejun: > > i using memcg v1, but some reason i want to context to memcg v2, > but i can't, here is my step: > #cat /proc/cgroups > #subsys_name hierarchy num_cgroups enabled > memory 5 1 1 > #cd /sys/fs/cgroup/memory > #mkdir a > #echo 0 > a/cgroup.procs > #sleep 1 > #echo 0 > cgroup.procs This doesn't do what you think. It will try to add a non-existant pid 0 to the root cgroup. You need to remove cgroup a. Moreover it is possible that the `sleep' command will fault some page cache and that will stay in memcg `a' until there is a memory pressure. cgroup v1 had force_empty knob which you can use to drain the cgroup before removal. Then you should be able to umount the v1 cgroup and mount v2. -- Michal Hocko SUSE Labs -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
