Ok, i am using a host tracking website to test my website load speed, i found it shows two difference results when i enter www, and without it. Also in Google webmaster tool, under site performance tab, it shows two different results for www.mydomain.com and mydomain.com Why?
might be caused by doubly hostname lookup, is the dns for both www and @ hosted in a same server? And if you are using absolute url linking for image/css/js, it might be the cause as well. Let me know the url and we'll take a look at it for you