I want to try cgroup v2 but am not sure if it is installed on my linux machine

```
>> uname -r
4.14.66-041466-generic

```

Since cgroup v2 is available in 4.12.0-rc5, I assume it should be available in the kernel version I am using.

<https://www.infradead.org/~mchehab/kernel_docs/unsorted/cgroup-v2.html>

However, it does not seem like my system has cgroup v2 as the memory interface files mentioned in its documentation are not available on my system.

<https://www.kernel.org/doc/Documentation/cgroup-v2.txt>

It seems like I still have cgroup v1.

```
/sys/fs/cgroup/memory# ls
cgroup.clone_children  memory.kmem.failcnt                 memory.kmem.tcp.usage_in_bytes   memory.memsw.usage_in_bytes      memory.swappiness
cgroup.event_control   memory.kmem.limit_in_bytes          memory.kmem.usage_in_bytes       memory.move_charge_at_immigrate  memory.usage_in_bytes
cgroup.procs           memory.kmem.max_usage_in_bytes      memory.limit_in_bytes            memory.numa_stat                 memory.use_hierarchy
cgroup.sane_behavior   memory.kmem.slabinfo                memory.max_usage_in_bytes        memory.oom_control               notify_on_release
docker                 memory.kmem.tcp.failcnt             memory.memsw.failcnt             memory.pressure_level            release_agent
memory.failcnt         memory.kmem.tcp.limit_in_bytes      memory.memsw.limit_in_bytes      memory.soft_limit_in_bytes       tasks
memory.force_empty     memory.kmem.tcp.max_usage_in_bytes  memory.memsw.max_usage_in_bytes  memory.stat 

```

**Follow-up questions**
Thanks Brian for the help. Please let me know if I should be creating a new question but I think it might be helpful to other if I just ask my questions here.

1) I am unable to add cgroup controllers, following the command in the doc

```
>> echo "+cpu +memory -io" > cgroup.subtree_control

```

However, I got "echo: write error: Invalid argument". Am I missing a prerequisite to this step?

2) I ran a docker container but the docker daemon log complained about not able to find "/sys/fs/cgroup/cpuset/docker/cpuset.cpus". It seems like docker is still expecting cgroupv1. What is the best way to enable cgroupv2 support on my docker daemon?

```
docker -v
Docker version 17.09.1-ce, build aedabb7

```