A local GPS-disciplined NTP server, distributing time over 1GbE or 10GbE goes a long way. I can't think of any application, besides HFT and maybe some science e

A local GPS-disciplined NTP server, distributing time over 1GbE or 10GbE goes a long way. I can't think of any application, besides HFT and maybe some science experiments that need better precision. And even in HFT, it is silly to try to use your x64 system time to get nanosecond precision. Even if you are really good, using bare hardware, all your code and data is in L2, an x64 system would still be giving you 100ns level jitter. No matter what you do. What you want is to have your network card (or FPGA) timestamping the packets accurately. And then releasing these packets at a precise timestamp. Saying that, maybe Clockwork is doing something completely different. And not in nanosecond level, but at a millisecond level. They talk about "measure true one-way delays of a packet or remote procedure call, discover network bottlenecks and "hiccups" (outages lasting a few seconds), and identify underperforming VMs arising from "noisy neighbors." Now, that could indeed be useful.