alt Hacker News> and allows you to make much stronger guarantees than TrueTime (due to higher precision distributed ordering guarantees, which translate to lower latency and higher throughput distributed writes).
TrueTime is the software algorithm for managing the timestamps. It’s agnostic to the accuracy of the underlying time source. If it was inaccurate then you get looser bounds and as you note higher latency. Google already does everything you suggest for TrueTime while also having atomic clocks in places.
Yup! I was referring to the original TrueTime/Spanner papers, not whatever's currently deployed. The original paper makes reference to distributed ordering guarantees at the milliseconds' scale precision, which implies many more transactions in flight in the uncertain state and coarser distributed ordering guarantees than the much tighter upper bound you can set with nanoseconds' precision and microseconds' comms latency...