How can I debug why safari is so slow loading a page sometimes?

Question

On Mac OS X 10.6.4 with Safari 5.0.1 I entered a web address in the browser bar and sometimes it's lighting fast, and sometimes terribly slow. My wifi connection has a perfect signal strength and the router is a cable modem from Time Warner.

I want to find out exactly where the bottle neck is when a page is loading slow so I can then fix that problem. This isn't a case where the site I'm connecting to happens to have a lot traffic that day and it's just slow, this is a recurring problem with this mac and this wifi connection. Often if I just quit Safari and re-launch it the same URL will load very quickly.

What tool can I run to basically see the http call in debug mode?

Answer 1

You can use the timeline of web inspector. First turn on the Develop menu (Preferences... Advanced... Show develop menu in menu bar) Then choose Show inspector on the new Develop menu... Click on Timeline... Click on record (the black dot in the bottom left of the screen)

You should now get all kinds of timing.

However, I suspect the culprit may be your DNS server. Try changing it to OpenDNS. Here's some instructions on how to change it.