Increase the disk size of container

Hello community,

I am running docker 1.11.2 on ubuntu 14.04. Inside the container I fired this command -

> root@34ab6efd089f:/# df -h
> Filesystem Size Used Avail Use% Mounted on
> _none 37G 27G 8.3G 77% /_
> tmpfs 1.9G 0 1.9G 0% /dev
> tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
> /dev/sda9 37G 27G 8.3G 77% /etc/hosts
> shm 64M 0 64M 0% /dev/shm

From here I can understand that my container has 37GB out of which 27 GB is already used(How can it happen ??. This is too big in terms of disk usage for linux container). I tried copying a file of 20 GB to this container and found that, after 9GB (or so) , I got a message for lack of disk space.

I want to my containers to have 50GB of space.
I visited link https://docs.docker.com/engine/userguide/storagedriver/device-mapper-driver/ but found nothing.

Please help.

do you have any resolution right now?