Docker's network configuration, causing Docker to use the Internet very slowly problems and solutions

Background:
While using Docker, there is no specific configuration of the Docker network, but using the network in Docker after a short period of time becomes very slow, curl a network request to about 20s, if curl when specifying IPV4-4 time is 5s. The same URL for Curl on host host is 0.01s.

Workaround:
Then, in the official Docker document, we found that Docker could configure the network option, so it was simply rude to use the

Make Docker use the host's network directly to solve the problem, but note that the same network configuration should be aware of the port conflicts, the listening port in Docker if and host conflict will cause the service to start up.

Docker Network Configuration Official documentation
https://docs.docker.com/v1.8/articles/networking/