容器和虚拟机 Container vs VM

六、容器和虚拟机 - 图1

容器不是Mini虚拟机

  • 容器其实是进程Containers are just processes
  • 容器中的进程被限制了对CPU内存等资源的访问
  • 当进程停止后，容器就退出了

容器的进程process

  • 显示容器的进程：docker container top <container ID>
    六、容器和虚拟机 - 图2

Note
以下是在Ubuntu20.04中演示，因Windows环境下的Docker和Linux具有一些差异。pstree 命令需要额外安装，可以使用 yum install psmisc 或者 sudo apt-get install psmisc 安装

  1. ➜  ~ docker container run -d nginx
  2. 57fe4033dd7e1e620a0b6a7b83b85d4f8f98772f0ce585624c384de254826fd0
  3. ➜  ~ docker container ls
  4. CONTAINER ID   IMAGE     COMMAND                  CREATED         STATUS         PORTS     NAMES
  5. 57fe4033dd7e   nginx     "/docker-entrypoint.…"   4 seconds ago   Up 3 seconds   80/tcp    festive_proskuriakova
  6. ➜  ~ docker container top 57f
  7. UID                 PID                 PPID                C                   STIME               TTY                 TIME                CMD
  8. root                7646                7625                0                   12:14               ?                   00:00:00            nginx: master process nginx -g daemon off;
  9. systemd+            7718                7646                0                   12:14               ?                   00:00:00            nginx: worker process
  10. ➜  ~
  11. ➜  ~
  12. ➜  ~  ps -aef --forest
  13. UID        PID  PPID  C STIME TTY          TIME CMD
  14. root         1     0  0 May14 ?        00:00:00 /init
  15. root       157     1  0 May14 ?        00:00:00 /init
  16. root       523   157  0 May14 ?        00:02:32  \_ /usr/bin/dockerd -p /var/run/docker.pid
  17. root       545   523  0 May14 ?        00:25:55  |   \_ containerd --config /var/run/docker/containerd/containerd.toml --log-level info
  18. root      7625   157  0 12:14 ?        00:00:00  \_ /usr/bin/containerd-shim-runc-v2 -namespace moby -id 57fe4033dd7e1e620a0b6a7b83b85d4f8f98772f0ce585624c384de254826fd0 -address /var/run/d
  19. root      7646  7625  0 12:14 ?        00:00:00      \_ nginx: master process nginx -g daemon off;
  20. systemd+  7718  7646  0 12:14 ?        00:00:00          \_ nginx: worker process
  21. root      6442     1  0 May18 ?        00:00:00 /init
  22. root      6443  6442  0 May18 ?        00:00:00  \_ /init
  23. penxiao   6444  6443  0 May18 pts/2    00:00:01      \_ -zsh
  24. penxiao   7770  6444  0 12:15 pts/2    00:00:00          \_ ps -aef --forest
  25. ➜  ~
  26. ➜  ~ pstree -halps 7718
  27. init,1
  28. └─init,157
  29.     └─containerd-shim,7625 -namespace moby -id 57fe4033dd7e1e620a0b6a7b83b85d4f8f98772f0ce585624c384de254826fd0 -address /var/run/docker/containerd/containerd.sock
  30.         └─nginx,7646
  31.             └─nginx,7718

Gain Access to the MobyLinux VM on Windows or MacOS

https://nickjanetakis.com/blog/docker-tip-70-gain-access-to-the-mobylinux-vm-on-windows-or-macos