A Tune challenge from Foundations. Launch day. Traffic will climb from nothing to 450 requests a second in fifteen seconds, three times a normal day. The autoscaler adds machines, but each new one takes four seconds to start. The team wants no burst of errors while the machines start. Keep every second clean, and spend as little as you can.
The design you start with: p99 237ms, 15% of requests failing, 123/s answered.