One of the most important parts about this is that they applied backpressure to the load balancing process: > We also decided that if a provider is slow to del

One of the most important parts about this is that they applied backpressure to the load balancing process: > We also decided that if a provider is slow to deliver messages, measured in the same way as before, we would reduce their share of the load by 10 percentage points When doing systems design this is a critical piece to include in almost all load balancing aspects. Because a ton of time you will start with 100% of traffic load balanced between two boxes but what happens when one box fails or slows down? You don't want to overwhelm anything which leads to cascading failures.