The IE performance when loading a lot of events has been improved in the latest release (7.2):
http://www.daypilot.org/daypilot-pro-for-asp-net-webforms-7-2.html
The event loading (parsing) has been optimized and the effect is particularly visible in IE.
However, if you are displaying a lot of events on a big screen it may take a lot of time to render everything. There is some room for optimization (choosing the best loading/rendering model) but you can't beat the browser limits.
Compare the performance of the following three demos:
You can try the following:
- Make the visible area smaller by adjusting the dimension of the control (HeightSpec + Height, Width) or by making the cells bigger (EventHeight, CellWidth).
- Show a smaller number of Days.
- Try to switch to the CssOnly mode (it renders fewer DOM elements).