Our web app mainly depends on radcontrols and it is somewhat complex and takes a quiet long time to load. We are in between optimizing everything and came across the light weight rendering. How it differ in terms of speed from the usual rendering process?
Telerik RadControls for ASP.NET AJAX supports Classic Rendering as well as Lightweight Rendering. You can now switch the rendering of RadControls such as Calendar,
Window,
Tooltip,
Dock and
FormDecorator
to one based on HTML5 and CSS3. This will result in more
lightweight HTML, CSS and resources used by your application and thus –
in better performance. In case of Lightweight rendering the size of loaded resources (FileSize/Number of files) will be less compared to the Classic rendering mode and hence the speed/performance is improved. For example the Classic Rendering of RadFormDecorator loads 529kb/7 files whereas in Lightweight rendering it requires 397kb/4 files and this is how the speed is boosted.
You can also have a look at this thread on Telerik controls performance tuning.