Just say you have 50 vhost files configured and your server is under load for apache, what is a good way to see which site is getting trafficked the most? Obviously tailing access logs can only be done one at a time, you could use apachetop, but that only points to one file at a time (I think). You could check the size of the access logs on the filesystem and the largest one is probably getting the most hits. Any better ideas to achieve this?
The best way would be to setup awstats/webalizer or a similar tool that will give you detailed stats but if you want do it on console then apachetop is the way to go and you can tail look into multiple files at a give time.
Command to view multiple files using apachetop :
Reference : http://nethack.ch/2013/01/24/find-out-the-website-causing-high-load-on-a-apache-webserver/