Performance for large numbers of files

[ghost]

I have a component that has a property of the currently selected file.
When the selected file changes it currently rebuilds the background data for Treebeard (held in a state) so that the component renders again (this is done to set the 'active' value on the correct node).
When we have large numbers of files in the tree (often we have ~=1000) there is a very noticeable delay (2-3 seconds) for the newly selected file to be shown
Is there a pattern for large datasets to set (for example) 'active' on a node without rebuilding all of the data?