When running the attached program, a very substantial memory leak can be observed. The leak arises whenever the integer 'model' property of the NodeInstantiator is updated. The leak can also be observed when using a QAbstractItemModel that emits the modelReset signal.

The leak is present even if the timer interval is set to much longer values (e.g. 500 ms)

The leak can be reduced, but not eradicated, by moving the instantiation of components out of Sphere and passing them in as properties that are shared between all instances of Sphere.

The leak is significant enough that it is a barrier to using Qt3D to implement the GUI of a CAD tool where the scene content is regularly updated.

In Qt5.7.1 the attached example crashes almost immediately. In 5.8.0_rc, a fix was put in place that reduces crashes, but a crash is occasionally observed - stack trace attached.

seanharmer May be interested in this.