由于brew的镜像源在国外，所以日常下载过程中很慢，不过我们可以把镜像源修改为国内的
源链接：https://blog.csdn.net/weixin_43664907/article/details/103369045
清华大学brew官网：https://mirrors.tuna.tsinghua.edu.cn/help/homebrew/
修改为国内镜像源
cd /usr/local/Homebrew
git -C "$(brew --repo)" remote set-url origin https://mirrors.tuna.tsinghua.edu.cn/git/homebrew/brew.git
git -C "$(brew --repo homebrew/core)" remote set-url origin https://mirrors.tuna.tsinghua.edu.cn/git/homebrew/homebrew-core.git
git -C "$(brew --repo homebrew/cask)" remote set-url origin https://mirrors.tuna.tsinghua.edu.cn/git/homebrew/homebrew-cask.git
brew update
复原的方法
cd /usr/local/Homebrew
git -C "$(brew --repo)" remote set-url origin https://github.com/Homebrew/brew.git
git -C "$(brew --repo homebrew/core)" remote set-url origin https://github.com/Homebrew/homebrew-core.git
git -C "$(brew --repo homebrew/cask)" remote set-url origin https://github.com/Homebrew/homebrew-cask.git
brew update