docker 容量统计
镜像大小
$ docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
foonathan/micro_cpp_gcc latest a7f7b545ecc9 4 days ago 205MB
centos latest 67fa590cfc1c 2 weeks ago 202MB
alpine latest 961769676411 2 weeks ago 5.58MB
ubuntu 18.04 a2a15febcdf3 3 weeks ago 64.2MB
ubuntu latest a2a15febcdf3 3 weeks ago 64.2MB
ubuntu 16.04 5e13f8dd4c1a 6 weeks ago 120MB
ubuntu 14.04 2c5e00d77a67 3 months ago 188MB
centos 7.4.1708 9f266d35e02c 5 months ago 197MB
其中 SIZE 字段即容器镜像的大小。
容器大小
$ docker ps -s
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES SIZE
4658613cfbbe alpine "/bin/sh" 36 minutes ago Up 36 minutes nervous_rosalind 22.7MB (virtual 28.3MB)
d3ec136444e9 ubuntu:18.04 "/bin/bash" 48 minutes ago Up 48 minutes heuristic_moser 45MB (virtual 109MB)
7e3937a94ff2 alpine "/bin/sh" 16 hours ago Up 16 hours happy_lumiere 5.59GB (virtual 5.6GB)
其中 SIZE 字段中包含两个数值，括号之前的为容器可写层的大小，括号内的为容器总的（即容器镜像加上容器可写层）大小。
完整的容量统计
$ docker system df --verbose
Images space usage:
REPOSITORY TAG IMAGE ID CREATED SIZE SHARED SIZE UNIQUE SIZE CONTAINERS
foonathan/micro_cpp_gcc latest a7f7b545ecc9 4 days ago 205.2MB 0B 205.2MB 0
centos latest 67fa590cfc1c 2 weeks ago 201.9MB 0B 201.9MB 0
alpine latest 961769676411 2 weeks ago 5.577MB 0B 5.577MB 2
ubuntu 18.04 a2a15febcdf3 3 weeks ago 64.18MB 0B 64.18MB 1
ubuntu 16.04 5e13f8dd4c1a 6 weeks ago 120.3MB 0B 120.3MB 0
ubuntu 14.04 2c5e00d77a67 3 months ago 188.2MB 0B 188.2MB 0
centos 7.4.1708 9f266d35e02c 5 months ago 196.6MB 0B 196.6MB 0
Containers space usage:
CONTAINER ID IMAGE COMMAND LOCAL VOLUMES SIZE CREATED STATUS NAMES
4658613cfbbe alpine "/bin/sh" 0 22.7MB 39 minutes ago Up 39 minutes nervous_rosalind
d3ec136444e9 ubuntu:18.04 "/bin/bash" 0 45MB 51 minutes ago Up 51 minutes heuristic_moser
7e3937a94ff2 alpine "/bin/sh" 0 5.93GB 16 hours ago Up 16 hours happy_lumiere
Local Volumes space usage:
VOLUME NAME LINKS SIZE
Build cache usage: 0B
CACHE ID CACHE TYPE SIZE CREATED LAST USED USAGE SHARED
可以看到，这里的 SIZE 是容器可写层的大小。
参考资料
How to analyze disk usage of a Docker container
https://stackoverflow.com/questions/26753087/how-to-analyze-disk-usage-of-a-docker-container
Explain the SIZE column in “docker ps -s” and what “virtual” keyword means
https://github.com/docker/docker.github.io/issues/1520#issuecomment-305179362
最后修改于 2019-09-07