Performance of TreeView is very low

When a TreeView has many expanded nodes it rendered with lags. In the attached example you can try to expand several folders which have many subdirectories (Windows, System32...).

Also ScrollPane does not work correctly when parent item with many children expanded (as you can see in the attached screenshots TreeView has more items but they are not displayed (1.png & 2.png), but collapse->expand parent item fixes this (3.png)).


I've attached information from JProfiler when the application is completely hung.