docker 的存储文件/var/lib/docker/devicemapper 占用磁盘空间 32G.，不知道怎么处理，网上说换文件系统，大家有没什么好办法啊。请赐教

[root@localhost devicemapper]# df -h
文件系统                 容量  已用  可用 已用% 挂载点
/dev/mapper/centos-root   38G   35G  2.6G   94% /
devtmpfs                 1.9G     0  1.9G    0% /dev
tmpfs                    1.9G     0  1.9G    0% /dev/shm
tmpfs                    1.9G   33M  1.9G    2% /run
tmpfs                    1.9G     0  1.9G    0% /sys/fs/cgroup
/dev/sda1                497M  166M  332M   34% /boot
/dev/mapper/centos-home   19G  3.8G   15G   21% /home
tmpfs                    380M     0  380M    0% /run/user/0
/dev/dm-5                 10G  181M  9.9G    2% /var/lib/docker/devicemapper/mnt/b27d54017544b1bb1a135352e6113feb7eda93b01b315d9733cd9ec1bfa8b8b3
shm                       64M     0   64M    0% /var/lib/docker/containers/6fae95c596ee5ba0afb1d7419f03cd371b05f800e3cc87d710355039a0957bfb/mounts/shm
[root@localhost devicemapper]# du -d 1 -h
1.2M    ./metadata
31G ./devicemapper
148M    ./mnt
31G .
[root@localhost devicemapper]# pwd
/var/lib/docker/devicemapper

很重要的提示

[root@localhost devicemapper]# docker info
Containers: 3
 Running: 1
 Paused: 0
 Stopped: 2
Images: 743
Server Version: 18.05.0-ce
Storage Driver: devicemapper
 Pool Name: docker-253:0-2612101-pool
 Pool Blocksize: 65.54kB
 Base Device Size: 10.74GB
 Backing Filesystem: xfs
 Udev Sync Supported: true
 Data file: /dev/loop0
 Metadata file: /dev/loop1
 Data loop file: /var/lib/docker/devicemapper/devicemapper/data
 Metadata loop file: /var/lib/docker/devicemapper/devicemapper/metadata
 Data Space Used: 32.98GB
 Data Space Total: 107.4GB
 Data Space Available: 2.777GB
 Metadata Space Used: 26.71MB
 Metadata Space Total: 2.147GB
 Metadata Space Available: 2.121GB
 Thin Pool Minimum Free Space: 10.74GB

WARNING: devicemapper: usage of loopback devices is strongly discouraged for production use.
         Use `--storage-opt dm.thinpooldev` to specify a custom block storage device.