Understanding space needed by Images and Containers

General Discussions
1

Hello,

I am a bit surprised about the size of the folder containing my docker images and containers:

60G     /mnt2/RockOn_Docker_Images_new/btrfs
31G     /mnt2/RockOn_Docker_Images_new/containers
15M     /mnt2/RockOn_Docker_Images_new/graph
16K     /mnt2/RockOn_Docker_Images_new/linkgraph.db
68K     /mnt2/RockOn_Docker_Images_new/network
4.0K    /mnt2/RockOn_Docker_Images_new/repositories-btrfs
0       /mnt2/RockOn_Docker_Images_new/tmp
0       /mnt2/RockOn_Docker_Images_new/trust
15G     /mnt2/RockOn_Docker_Images_new/volumes

I have run docker_gc over it already.

Now, if analyze my images in http://imagelayers.io (link to myassessment), I see that the images and containers should take 2gb, only.

Also, docker ps -s does not reveal the cause:
http://pastebin.centos.org/43766/

So, where can I search now?

Regards,
Hendrik

2

What storage driver are you using? What’s the output of docker info?

3

Hello Jeff,

thanks for your reply.
I am using BTRFS as the storage driver.
here the docker info:

Containers: 11
Images: 196
Server Version: 1.9.1
Storage Driver: btrfs
 Build Version: Btrfs v3.16.2
 Library Version: 101
Execution Driver: native-0.2
Logging Driver: json-file
Kernel Version: 4.4.5-1.el7.elrepo.x86_64
Operating System: Rockstor 3 (Core)
CPUs: 2
Total Memory: 19.52 GiB
Name: homeserver
ID: 5TNM:6MXO:D355:NG7I:MBOA:3B3S:26ME:NX5A:BYY7:UDUK:3JPB:UU6S
Username: henfri
Registry: https://index.docker.io/v1/
WARNING: bridge-nf-call-iptables is disabled
WARNING: bridge-nf-call-ip6tables is disabled

Greetings,
Hendrik

4

Hendrik,

Have you already read through: https://docs.docker.com/engine/userguide/storagedriver/btrfs-driver/? The driver is considered experimental.

Mary

5

Hello Mary,

thanks. Do you have anyting in particular in mind on that Page?
I do understand the concept behind the btrfs storage driver; I don’t see a hint there how to understand the space required, by each image&container though.

I don’t understand at all, why the space required is growing my 2 GB per day.

Greetings,
Hendrik

6

Hello,

can I do anything to further clarify my question?

Greetings,
Hendrik