First, let me say that I know AWS doesn’t promise anything about network performance as it relates to packets. At best, they leave it as a multivariate calculus problem for the reader — inclusive of CPU performance, code optimization, MTU, and current network congestion under the VLANs. But still, I was curious to see if there was any correlation to Amazon’s published “Network Performance” and the actual packets per second metric I tested.

Remember the customer who reported a hard-coded packet per second (PPS) limit in AWS? His use case was a reverse-proxy server to a very active database cluster, complete with heartbeats, keep-alive connections, and a heavy load of queries and traffic. When the network throughput was sustained for an hour or so, the throughput would drop despite increasing demand.

A customer of ours reported a limit on number of packets in Amazon’s EC2 instances. According to the report, it didn’t happen on all instance types, and didn’t happen all the time. Also, it was unrelated entirely to bandwidth or MTU. According to the report, packet transmission rates were limited the same as CPU on t2/t3 instances — each instance earns credits which, when exhausted, cause throttling.

If you remember getting an Erector Set as a kid, I’m sorry. In a stocking full of toy building systems, an Erector Set is the proverbial lump of coal. The instructions are complicated, and the pieces are made of metal, connected together with tiny screws. Few children have ever completed one of these sets successfully.