simulation 01 — one box, too much traffic
A single application server behind no load balancer. Traffic has outgrown it and requests are being dropped. Add capacity — but a second server does nothing until something in front of it decides where requests go.
pass when
error rate ≤ 2% · p99 ≤ 400ms · spend ≤ $400
The simulation reads best on a wider screen — the topology is drawn left to right.
Ready to run.
served
0
dropped
0
error rate
0.0%
p99
0ms
in flight
0
build
spend$100 / $400
Capacity is never free. Passing under budget is the whole exercise.