Dojo or Cappuccino or Sproutcore in term of speed and memory usage?

I want to develop a web application, but I need a strong and recent speed&memory comp开发者_StackOverflow中文版arison between Dojo, Cappuccino and Sproutcore, preferably latest version;

http://en.wikipedia.org/wiki/Program_optimization#When_to_optimize

This is really hard to answer without more context about what you're trying to build. By their very nature Cappuccino and SC add a fairly large amount of boilerplate/complexity on page load. Great if you're building single page applications (think Gmail, with a ~10s page load, but you only do that once a session), useless if you're building Web 2.0 style web sites (think Facebook, new pageload every few mins), as page loads are cripplingly slow with Cappuccino and SC.

Which leads to another interesting question. What are you trying to optimize (do you even know yet?). Page load? Data latency? UI responsiveness?

For most front end apps the cost of retrieving data from the server is an order of magnitude greater bottleneck than the front end code anyway.