经常要clone github中的一些项目，无奈如果不爬梯子的话速度实在是龟速，经常1k/s，于是搜了下解决方法，改HOSTS大法。
Windows下在C:/Windows/system32/drivers/etc/hosts
Ubuntu等linux系一般在/etc/hosts
在hosts中添加如下内容：
# Github
151.101.44.249 github.global.ssl.fastly.net
192.30.253.113 github.com
103.245.222.133 assets-cdn.github.com
23.235.47.133 assets-cdn.github.com
203.208.39.104 assets-cdn.github.com
204.232.175.78 documentcloud.github.com
204.232.175.94 gist.github.com
107.21.116.220 help.github.com
207.97.227.252 nodeload.github.com
199.27.76.130 raw.github.com
107.22.3.110 status.github.com
204.232.175.78 training.github.com
207.97.227.243 www.github.com
185.31.16.184 github.global.ssl.fastly.net
185.31.18.133 avatars0.githubusercontent.com
185.31.19.133 avatars1.githubusercontent.com
改完之后立刻刷新，
Windows：ipconfig /flushdns
Ubuntu：sudo systemctl restart nscd
Mac：sudo killall -HUP mDNSResponder