So lets assume that the MTU remains at 1500 bytes, we are talking about 8 millions packets a second being processed on each side. The most I have seen a modern machine do for full default MTU sized packets is about 80,000 and that used multiple cpu's on the receive side. Jumbo frames might reduce the number of packets to around 1 million. The thing is that CPU's are not getting that much faster, they are getting far more cores on the processor which leads me to think 2 things will have to happen before 100 gigabit Ethernet become viable :-
- Most/all the TCP and IP processing will need to be done in hardware on the NIC
- A lot of TCP stacks will have to be re-written to become far more multi-threaded
It does make me wonder if TCP is the right protocol to be running in the data centre on to of 40 or 100G?