I would like to share my experience from using self.layer.shouldRasterize = YES; flag on UIViews.
I have a UIView class hierarchy that has self.layer.shouldRasterize turned ON in order to improve scrolling performance (all of them have STATIC subviews that are larger than the screen of the device).
Today in one of the subclasses I used CAEmitterLayer to produce nice particle effects.
The performance is really poor although the number of particles was really low (50 particles).
What is the cause of this problem?