We have a performance issue with RadGridView when using telerik's grouping.
Sorting can take about 4 seconds. while sorting without grouping, lasts less then a second.
The same issue happens when clearing the ItemSource and then use AddRange of several items.
The JetBrains dotTrace shows that most of the time spent in "Telerik.Windows.Controls.GridView.GridViewVirtualizingPanel.MeasureOverride(size)" - 2471 milliseconds. The same operation lasts 79 Milliseconds without grouping.
We defined the gridview with the following:
GroupRendererMode = "Flat"
VirtualizingPanel.IsVirtualizingWhenGrouping = "True"
VirtualizingPanel.IsVirtualizing = "True"
In addition, the height and the columns width are fixed size.
We hope you can help us.
Thank you in advance.