@Amna_Arshad , Maybe you should read the “Back-of-the-envelope Calculations” lesson again? There’s no mention of why the number of servers is calculated by dividing the number of users over the server’s req/seconds.
Any reason why we can’t just use 3 servers globally? Just saying so ain’t going to fly. 3 server’s . I think OP’s calculations are realistic and they actually make sense. All, we are talking is the ability to just serve a simple request. Things’ definitely change when there’ some processing going on… In those cases, a single server definitely can’t serve 500 rps. So, either choose the right rps a server can handle and calculate correctly or just use a random rps and then calculate the number of servers and end up with weird(3 server in this case) values. Please just don’t say “You can’t use 3 servers to serve globally” without giving proper explanation!
Edit 1: You should really check the cost of 7500 server’s with 32cores,256GB ram. follwing is the estimate per month for just processing servers. And we also will have ton of other things like DB, cache, LB etc etc
Course: https://www.educative.io/collection/10370001/4941429335392256
Lesson: https://www.educative.io/collection/page/10370001/4941429335392256/4552284171665408
Course: https://www.educative.io/collection/10370001/4941429335392256
Lesson: https://www.educative.io/collection/page/10370001/4941429335392256/4552284171665408