Yeah, for normal web app, we can easily have 100x users for each step mentioned in article. For our company, we had more than 500k users with 1 small nginx + 1

Yeah, for normal web app, we can easily have 100x users for each step mentioned in article. For our company, we had more than 500k users with 1 small nginx + 1 medium appServer(with autoscaling, though never needed it) + 1 small cache server and RDS till now. We just added a aws managed load balancer into the setup and think it might be overkill. For a client with NewsFeed needs, I used a dedicated server(64GB, 2TB space) to run nginx, app, cache, huge elasticsearch and postgres. It was great(and cheap) option for an MVP and let them validate the product for few months with >10k users. It was awesome to learn a few years ago, how much compute power we don't use.