Question

我使用Dockerfile in this repo构建了一个图像，因为它在opencv源文件上执行了make，图像大小增加了3.1 GB。因此，为了减小图像的大小，我在安装OpenCV后删除了源文件和构建文件，如果我检查图像的大小，它确实显示大小已经减少但是当我使用docker images命令检查时大小保持不变。

这是docker build

的输出

RUN echo "Size of image before installing OpenCV"
 ---> Using cache
 ---> 6408d5fde660
Step 11 : RUN echo `du -sh /`
 ---> Running in 70e945c95f0c
1.9G /
 ---> 60f80a0d27e6
Removing intermediate container 70e945c95f0c
Step 12 : RUN cd ~/ &&    git clone......
Step 14 : RUN echo "Size of image AFTER installing OpenCV"
 ---> Using cache
 ---> 1e065271efa7
Step 15 : RUN echo `du -sh /`
 ---> Running in 0f82de699dd9
5.9G /
 ---> a90660ac1f25
Removing intermediate container 0f82de699dd9
Step 16 : RUN echo "Size of OpenCV source and build directories"
 ---> Running in 7412b1e468e8
Size of OpenCV source and build directories
 ---> 252b6d0ef5b7
Removing intermediate container 7412b1e468e8
Step 17 : RUN echo `du -sh ~/opencv*`
 ---> Running in 8fddb31f4770
3.8G /root/opencv 218M /root/opencv_contrib
 ---> 3f9c355fec15
Removing intermediate container 8fddb31f4770
Step 18 : RUN rm -rf ~/opencv*  # This removes
 ---> Running in 8a6c823f5675
 ---> 96af8b3d01bf
Removing intermediate container 8a6c823f5675
Step 19 : RUN echo "Size of image AFTER removing OpenCV source and     build directories"
 ---> Running in e292c233f8db
Size of image AFTER removing OpenCV source and build directories
 ---> b08582019c1b
Removing intermediate container e292c233f8db
Step 20 : RUN echo `du -sh ~/opencv*`
 ---> Running in 9cb62f3be3b3
du: cannot access '/root/opencv*': No such file or directory
 ---> 74473a783265
Removing intermediate container 9cb62f3be3b3

Step 21 : RUN echo `du -sh /`
 ---> Running in 45c9fcedf650
1.9G /
 ---> 0350a13a1a3b
Removing intermediate container 45c9fcedf650
Successfully built 0350a13a1a3b

从最后一步看，图像大小应该是1.9GB，但当我docker images时，它显示我6.298 GB

➜  d1 docker images
REPOSITORY TAG     IMAGE ID      CREATED       SIZE
ubuntu_py latest 0350a13a1a3b 11 seconds ago  6.298 GB

即使容器尺寸也正确显示，

➜  d1 docker run -it ubuntu_py /bin/bash
root@b549d9716e19:/# ls
bin  boot  dev  etc  home  lib  lib64  media  mnt  opt  proc  root  run  sbin  srv  sys  tmp  usr  var
root@b549d9716e19:/# du -sh
1.9G    .
root@b549d9716e19:/#

Answer 1

Docker图层是不可变的。一旦它被创建，它就会留下来。如果你想构建一些东西，然后移除用于构建它的残余物，那么你需要在同一个RUN命令中执行这些事情，或者只是将所有内容分层。

编辑：事实上，删除文件也会产生略差效果，因为你要添加一个额外的图层，其中Docker必须 whiteout 要删除的文件，增加大小：p

＆＃34;码头图片＆＃34;命令没有显示正确的大小

1 个答案: