Slow switching between opened files in project

QtCreator freezes a lot when you switch between opened files in a large project.

I opened several files from a large project and simply double clicked on them in "Opened Documents" view. Then I did profiling with Apple Instruments tool from XCode package.

Here is the screenshot of the callstack which consumed most time:

Here is also trace file from Instruments to examine:
qtcreator_profiling.trace.zip

 This freeze makes work with QtCreator very uncomfortable.