Source : howtogeek 

As a webmaster, I’ve often wanted to be able to see real-time hits as they arrive. Sure, Google Analytics is a wonderful package for looking at trends over time, but there’s a delay of a few hours there, and you really can’t see data like requests per second or total bytes.

This is where the apachetop utility comes in. It’s a very simple command line utility that you can use to monitor traffic real-time. It accomplishes this by parsing the apache logfiles and displaying meaningful output to the screen.

Using apachetop