Quick question. How does Webpagetest know if its using CDN?

When the optimization checks are done Pagetest does a DNS lookup for the host name (as well as a reverse-lookup on the IP) and checks to see if the hostname is a CNAME to a known CDN.

This way we can maintain a short list of known CDN domains and get broad coverage. If you’re using a CDN that isn’t detected just shoot me a note and I can get it added to the next release.



This one please Pat:


Sure - looks like I’ll need to add *.lxdns.comto catch it correctly. Who is the CDN provider (so I can add a comment with the domain)?

It will be included in the next update.




Thanks! Is there a way i can just add it myself?

Not yet. The list is currently maintained in the pagetest code itself. I’ll probably add a facility to let it pull in an external list as well but it’s small enough and hasn’t changed frequently enough to be much of a problem to date.