Is there a better way to show processor usage in tmux?

Here's a solution that can consume a lot of CPU usage (steal from this article ):

there is a difference in my ubuntu 12 ec2 server

use instead, top -lninstead I have to use top -bn1,

Here is my sibling .tmux.conffile

set -g status-right '#[fg=yellow]#[(getCpuUsage.sh)]'

it actually calls the vertex every 2 seconds and displays all the information about the set, I think it should be less than the processor consumption or use some flag to limit the output of only the top processor cpu uage