Is EXT JS Fast Enough?

We are going to be producing a RIA that will also be available using Adobe AIR for database management and manipulation with a php back end.

In an effort to speed up develop开发者_Python百科ment we have decided on using YUI or EXT JS.

It appears that EXT JS out of the box will produce a better looking application than YUI but being essentially 100% JS I can foresee the application being much slower on any computers that aren't...say...up to date.

I am looking for any benchmarks comparing the two frameworks for UI & AJAX operations or any input about the speed of real world RIA applications using either framework.

Thanks for your help.

EDIT So is the general consensus that for a RIA where speed of use is a primary concern YUI is the better option? Or is it essentially, either will work?

EDIT EDIT We decided to go with YUI2 thanks for your help!

Don't fall into the trap of premature optimization. If only a small percentage of your users will be using "older" browsers, they will just have to deal with the slowness of any modern js framework - whether you choose YUI or Ext JS. Choose based on features and ease of development and applicability to your project.

When it comes to library size and speed of download to the browser - whichever library you choose, it can be customized to only include the components you need. And in production, you'll be minimizing and compressing it, so I think library size is really NOT a good measuring stick for making these types of decisions.

I posted a topic at the Ext JS forum years ago asking why the Ext Js doesn't come in packages and we are forced to use the kitchen-sink (almost). Their answer was "Ext JS is for RIAS".

I don't know what this tells you but in terms of size Ext JS is "big enough". I would recommend it for intranet apps. If you are to use it for public sites use all optimization techniques available to achieve fast loading times, compression, etc.

I also used YUI for intranet applications and i can tell you that it was lighter since not all packages where required.

We used to work with a gwt wrapper for ExtJs (gwt-ext). We developed a lot of modules with that. At some point we experienced some slow performance, specially with grid when the data was huge. In addition some memory leak with IE. But after they changed their licence policy, we started looking to other options. Perhaps some of those problems are fixed now.

Any way, now we are developing with OpenLaszlo.

I hope it helps you

If you're thinking of using Ext JS be aware that the current version (4.0.XX) has been found to be significantly slower than version 3.4, see http://www.sencha.com/forum/showthread.php?140180.

I've used YUI. It's fast. The newest library is highly modularized, so you only load modules you need. Also you can refer libraries from publicly available hosting services provided by Yahoo; it offers CDN for free.

I've worked with YUI data tables (data grids) with over 4,000 records and it still performed at an acceptable level.