Clean Docker /var/lib/docker/devicemapper

Question

Hello does anyone know how to clean docker devicemapper file ?

I've already cleaned all the images / containers but still the device mapper file is abnormally big:

 docker images -a
REPOSITORY               TAG                 IMAGE ID            CREATED                 SIZE
gitlab/gitlab-ce         latest              735fdb05ad5d        27 hours     ago        1.225 GB
<none>                   <none>              06fefa4a9183        6 weeks     ago         1.077 GB
rancher/agent-instance   v0.6.0              134980b9bbfb        6 months     ago        635.6 MB
<none>                   <none>              06d5beefe33e        6 months     ago        635.6 MB
<none>                   <none>              e172255e7648        6 months     ago        495.6 MB
<none>                   <none>              c20ca66652e8        6 months         ago        495.6 MB
<none>                   <none>              e736ae48fd3a        6 months     ago        483.8 MB
<none>                   <none>              8239904dd749        6 months     ago        472.1 MB
<none>                   <none>              b780de634713        6 months     ago        472.1 MB
<none>                   <none>              eda17c9d109e        6 months     ago        472.1 MB
<none>                   <none>              2ec6b457b5d8        6 months     ago        300.6 MB
<none>                   <none>              a15c0b4b75b1        6 months     ago        300.6 MB
<none>                   <none>              b6501c507a32        6 months     ago        300.1 MB
rancher/agent            v0.8.2              4de7ef5d11e3        8 months     ago        365 MB
<none>                   <none>              a0ff15f1f8ad        8 months     ago        365 MB
<none>                   <none>              4bb3b77da9b1        8 months     ago        365 MB
<none>                   <none>              8410b01d3f42        8 months     ago        365 MB
<none>                   <none>              4068f49bc382        9 months     ago        365 MB
<none>                   <none>              2a6ec0cadaec        9 months     ago        365 MB
<none>                   <none>              8ca7bc756812        9 months     ago        342.4 MB
<none>                   <none>              b6cc9819d3f4        9 months     ago        321.4 MB
<none>                   <none>              d760275f41ff        9 months     ago        306 MB
<none>                   <none>              1c524e41e113        9 months     ago        305.5 MB
<none>                   <none>              4bec63e16966        9 months     ago        260.8 MB
<none>                   <none>              574422a69939        9 months     ago        256.7 MB
<none>                   <none>              d5ddd9bb3635        9 months     ago        247.2 MB
<none>                   <none>              44ae5d2a191e        9 months     ago        188.3 MB
<none>                   <none>              62df8e845c12        9 months     ago        188.3 MB
<none>                   <none>              b6a4b778253d        9 months     ago        188.3 MB
<none>                   <none>              7d8a588d75a5        9 months     ago        188.1 MB
<none>                   <none>              3f55b715e2c4        2 years     ago         299.7 MB
<none>                   <none>              1bc5ec756ec9        2 years     ago         192.6 MB
<none>                   <none>              3463aff75755        2 years     ago         192.7 MB
<none>                   <none>              1013ce565837        2 years     ago         192.6 MB
<none>                   <none>              5806993e4389        2 years     ago         192.6 MB
<none>                   <none>              bd64f000e711        2 years     ago         192.6 MB
<none>                   <none>              e73baccf8d9e        2 years     ago         192.6 MB
<none>                   <none>              6b7491a446ad        2 years     ago         192.6 MB
<none>                   <none>              c2910096a074        2 years     ago         192.5 MB
<none>                   <none>              cf2172af6603        2 years     ago         192.5 MB

Images sums up to roughly 15gb while the devicemapper file is 30GB !

There is only one container running the will take at max another 1gb.

Is there a way to reduce it to a proper size WITHOUT having to remove docker and reinstall from stratch ? Something like a garbage collection tool to be executed once in a while ?

Answer 1

use following command:

docker rm -v $(docker ps -a -q -f status=exited)