It takes few milliseconds to save a value to Qt Creator's configuration database (~/.config/QtProject/QtCreator.db). But too many values are being saved while doing almost nothing – at start, exit, pressing ESC in editor, switching modes like "Edit", "Debug" or "Help".

I've attached backtrace at the point when the GUI is frozen and output from Qt Creator with some more debug info (I've set debug_settings=1 in src/plugins/coreplugin/settingsdatabase.cpp).