AWS charges to move bytes based on where they go. The expensive surprises are not the internet egress everyone expects, they are the cross-AZ chatter you cannot see. Here is the full rate ladder and the cheapest ways to cut the bill.
AWS NAT gateway pricing in us-east-1: $0.045 per hour (about $32 a month per gateway, per AZ) plus $0.045 per GB processed, billed on top of data transfer. A monthly cost table, how it compares to a free internet gateway, and the cheapest ways to cut it.
RDS is often the second or third biggest line on an AWS bill, sometimes the first, and most of it is avoidable. The levers that move it: fix the queries before you upsize, match the instance to your load shape, and stop provisioning storage for data that has not arrived yet.
A head-to-head benchmark of the same Spring Boot app built for the JVM and as a GraalVM native binary - on real AWS hardware with a real database, run multiple times. Native wins startup, memory, and predictability; the warm JVM wins the median, peak throughput, and often the tail too - but the JVM swings run-to-run while native stays flat.
