The speed with these libraries results in the page blinking every time I reload it (which it doesn't do if I don't use them). I also think that a speed of more than 0.9 seconds is inacceptable when it is published on the internet. If this is the speed at the localhost with 0 meters of traveling distance from the server to the client, then I'm scared to think about the time it would take after being published.
Are jQuery and jQueryUI slow libraries that you should normally avoid if you don't really need them?
Actually it depends on which JQuery library version you are using. The minified versions can speed up the web page. Also having them locally is a plus but you won't have the updated version (when you use a cdn you can have the latest).
What kind of external data do you load? Are they all using AJAX calls? What is your usual server connection?
These are the questions you should focus on.
when you use a cdn you can have the latest— are you suggesting simply including new versions without testing? Good luck with that - RobG 2012-04-04 02:07
jQuery and jQuery-UI are not slow by definition.
Abuse of these might slow down the page though - Do you really need hundred shiny effects?