docker查看容器占用磁盘大小

Docker 1.13引入了docker system df命令，类似于Linux上的df命令，用于查看Docker的磁盘使用情况。

$ docker system df
TYPE                TOTAL     ACTIVE    SIZE          RECLAIMABLE
Images              3         0         5.373GB       5.373GB (100%)
Containers          0         0         0B            0B
Local Volumes       0         0         0B            0B

查看单个image、container大小：docker system df -v

[root@localhost ~]# docker system df -v
Images space usage:
 
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE                SHARED SIZE         UNIQUE SIZE         CONTAINERS
mongo               latest              66c68b650ad4        5 weeks ago         387.8MB             64.21MB             323.6MB             1
rabbitmq            management          1c1e1f201079        7 weeks ago         181.5MB             151.4MB             30.09MB             1
rabbitmq            latest              3e5ddca64bb7        7 weeks ago         151.4MB             151.4MB             0B                  0
 
Containers space usage:
 
CONTAINER ID        IMAGE                 COMMAND                  LOCAL VOLUMES       SIZE                CREATED             STATUS                    NAMES
1a0bb1ac1c52        mongo                 "docker-entrypoint.s…"   1                   2.74MB              5 weeks ago         Up 7 hours                docker_mongodb
73417264c538        rabbitmq:management   "docker-entrypoint.s…"   1                   1.73kB              6 weeks ago         Exited (255) 2 days ago   rabbitmq
 
Local Volumes space usage:
 
VOLUME NAME                                                        LINKS               SIZE
13856e3cfd4af0a2d695cca746c4039213a66901c43326a3c14391c61bf07d21   0                   285.6MB
2e7a18c2cde8bc82ad145138d495b3bdfe7329870a130874ef11aff57df2a955   1                   0B
556df6317f798afb15cf6bdc8c6763ab45cabf2b09304545bcd319049ff61cef   1                   338.9MB
e7c82573f88c7e083445cbc611ed753ab26e36c73964fed323f7e38e3cb431b4   0                   440.5MB
 
Build cache usage: 0B
 
CACHE ID            CACHE TYPE          SIZE                CREATED             LAST USED           USAGE               SHARED

Docker提供了docker system prune，可以用于清理dangling镜像(参考What are Docker <none>:<none> images?)和容器，以及失效的数据卷和网络。

$ docker system prune
WARNING! This will remove:
    - all stopped containers
    - all volumes not used by at least one container
    - all networks not used by at least one container
    - all dangling images
Are you sure you want to continue? [y/N] y
Deleted Containers:
1cdf866157b4a97e151125af3c2a7f186a59b6f63807e2014ce1a00d68f44e1d
Deleted Images:
deleted: sha256:f59bb277...
deleted: sha256:695b8e70...
deleted: sha256:93b1cceb...
deleted: sha256:c74d6bcd...
deleted: sha256:df8b9bb1...
deleted: sha256:dfe8340f...
deleted: sha256:ce1ee654...
Total reclaimed space: 3.221GB

名称为<none>:<none>，为dangling镜像，因此会被删除。同时，所有的中间镜像也会被删除。

更进一步，使用-a选项可以做深度清理。这时我们会看到更加严重的WARNING信息:

$ docker system prune -a
WARNING! This will remove:
    - all stopped containers
    - all volumes not used by at least one container
    - all networks not used by at least one container
    - all images without at least one container associated to them
Are you sure you want to continue? [y/N] y
Deleted Images:
untagged: test:latest
deleted: sha256:c515ebfa2...
deleted: sha256:07302c011...
deleted: sha256:37c0c6474...
deleted: sha256:5cc2b6bc4...
deleted: sha256:b283b9c35...
deleted: sha256:8a8b9bd8b...
untagged: alpine:latest
untagged: alpine@sha256:58e1a1bb75db1...
deleted: sha256:4a415e366...
deleted: sha256:23b9c7b43...
Total reclaimed space: 2.151GB

这个命令将清理整个系统，并且只会保留真正在使用的镜像，容器，数据卷以及网络，因此需要格外谨慎。比如，我们不能在生产环境中运行prune -a命令，因为一些备用镜像(用于备份，回滚等)有时候需要用到，如果这些镜像被删除了，则运行容器时需要重新下载。

此时，所有未绑定容器的镜像将会被删除。由于第一次prune命令删除了所有容器，因此所有镜像(它们没有绑定任何容器)都会被删除。

参考：

https://blog.csdn.net/dmw412724/article/details/107126828

http://dockone.io/article/2258