Press Ctrl-A (Shortcut for "Select all" action) in TreeTable with ~1000 items Selection appears very slow. Cause: javax.swing.TreeNode.getChildCount() at javax.swing.tree.DefaultTreeSelectionmodel.addSelectionPath(TreePath) at com.intellij.util.ui.treetable.TreeTable$ListToTreeSelectionModelWrapper.updateSelectedPathsFromSelectedRows() at com.intellij.util.ui.treetable.TreeTable$ListToTreeSelecteionModelWrapper$ListSelectionHandler.valueChanged(ListSelectionEvent) at javax.swing.JComponent.processKeyEvent(KeyEvent) ... It will invoked approx. 6000000 cases for treetable with 100 items Maybe same problem can be reproduced also by Ctrl-A in "VCS File View" toolwindow with thousand shown files