To access the viewability optimization settings screen click the “viewability settings” button at the bottom of your container. On this screen you can choose how you would like your ads to be displayed, including turning on dynamic reevaluation and position optimization.
When enabled, this option will prioritize ad rendering based on the user’s viewport. Additional criteria for rendering priority will be enabled in future releases
User viewport priority – prioritizes loading the ads currently in the user’s viewport
Position: Top to bottom – loads ads by their page position, starting at the top
Revenue: Highest to Lowest – after setting expected revenue for ads prioritizes loading those with the highest CPM first
Ad size: Large to Small: prioritizes loading the largest ads first
Ad size: Small to Large: prioritizes loading the smallest ads first
Custom priority – manually configure a custom loading prioritization
This setting determines how the container will prioritize tags that do not relate to ads when loading the page. The two options are to prioritize all units within the frame first, then proceed based on the optimization method, or to focus on rendering all ads first before proceeding to the non-ad units.