Data Center switch latencies well below 3us. And still the OS network stack takes five times that much to process a packet.
This study from Stanford’s Stephen M. Rumble, Diego Ongaro, Ryan Stutsman, Mendel Rosenblum, and John K. Ousterhout summarizes the need to re-engineer operating systems in order to take advantage of ultra-low latencies. Fiber optics (that introduce 5ns/m of latency) and next-gen NIC silicon integrated into the CPU core will reduce the latency that other components introduce in the total calculation… but the OS is lagging behind, probably due to a lack of need for development in this area.
Now there is a need to improve in this area. Developers, we’re looking right at you.