Costs #1: Cycles to Process Packets


With minimal application, plus all overheads:
20k clock pulses (CP) per data packet

Protocol at 100k pps requires a 2 GHz CPU
e.g. to fill a GigE

Invariant across a wide range of architectures

Interrupt coalescing, etc. have only O(1) effects

Performance Races
Ethernet performance rises x10 every 3 years
CPU performance rises 7% every month
Alternating leadership