It's Time for Low Latency

The operating systems community has ignored network latency for too long. In the past, speed-of-light delays in wide area networks and unoptimized network hard-ware have made sub-100µs round-trip times impossible. However, in the next few years datacenters will be deployed with low-latency Ethernet. Without the burden of propagation delays in the datacenter campus and network delays in the Ethernet devices, it will be up to us to finish the job and see this benefit through to applications. We argue that OS researchers must lead the charge in rearchitecting systems to push the boundaries of low-latency datacenter communication. 5-10µs remote procedure calls are possible in the short term - two orders of magnitude better than today. In the long term, moving the network interface on to the CPU core will make 1µs times feasible.