We are seeing same issue even with an additional problematic: NSViews that are nearby the initial invalidated view are getting false drawRect events that causes unneeded additinal paintings. We posted a call out on LinkedIn under #drawrectgate - hope that it will be picked up by Apple soon!

We just discovered that this will also help a lot to prevent unneccesary drawings outside the needsdisplay rect: [view setWantsLayer: YES]; [[view layer] setDrawsAsynchronously: YES];