After I update to the Mac Yosemite , I found my zsh 5.0.6 in iterm2 2.0 always cost almost 100% cpu . And Sometimes, I have nothing to do in the zsh shell. But the cpu is always high. and you can see, it use almost 50% of my battery which is impossible usually. ➜ php-workspace ps aux | grep zsh algking 17732 89.5 0.1 2462096 2220 s000 S 10:53下午 11:22.84 zsh algking 5170 7.1 0.1 2470916 2988 s002 SN+ 六12下午 0:25.14 zsh -i algking 5166 0.3 0.0 2461012 616 ?? SN 六12下午 0:01.34 zsh /Users/algking/.zsh-autosuggestions/completion-server.zsh /tmp/zsh-autosuggest-algking /tmp/zsh-autosuggest-algking/pid /tmp/zsh-autosuggest-algking/socket algking 5169 0.0 0.0 2461012 4 s002 SNs 六12下午 0:00.00 zsh /Users/algking/.zsh-autosuggestions/completion-server.zsh /tmp/zsh-autosuggest-algking /tmp/zsh-autosuggest-algking/pid /tmp/zsh-autosuggest-algking/socket algking 18260 0.0 0.0 2452228 704 s000 S+ 11:06下午 0:00.00 grep zsh this is my plugin used : plugins=(osx autojump brew macports colored-man composer npm) source $ZSH/oh-my-zsh.sh