Recently, my department upgrade RadControl4AJAX to the latest one. When I tried the RadCombo for search, I think its performance is somewhat badly suffered in loading about 40K rows. Is there anyway to get it works faster or I have to reduce the record load?
The best approach to optimize the performance speed of Telerik RadComboBox when using huge amount of items is using the load-on-demand feature.The load-on-demand mechanism loads the items only when the user types or clicks in the field or the drop-arrow image. It filters the Items server-side before they are loaded in the control and the Filter feature performs filtering at client-side.
And I recommend you to retrieve data in portions - with use of ShowMoreResultsBox and Virtual Scrolling
Take a look at load on demo which demonstrates the various Load On Demand Modes.