Hey I'm very glad to see that people now care about *real* issues in virtualized environments ! I spend my time explaining to some people that those are fine until you need to achieve high PPS rates. Another issue that you didn't mention / experience here is that when you're hitting the 100k PPS limit, the physical machine is on its knees, and other VMs running on the same host will be similarly impacted. So if you want to run a VM with a load balancer and another one with your web server, the limit will probably be around 50-75k PPS (assuming you're alone on that host, which is obviously not the case). For these reasons, the only way to achieve high network data rates is to group together in same instances the services which need to exchange a lot of data, and to use a large number of instances in order to hope to keep some bandwidth on some physical hosts, in the event someone else' instance sharing the same physical host as yours makes heavy use of the traffic.