API to correlate system time with external time sources #28977
Some notes on the design, with a few questions that should be answered before it's ready to merge:
What is this?
There's already a
It then adds API under
The API does not automatically do time maintenance. Something has to invoke
Why isn't this
@pabigot Would it be feasible to drop the
I tried that. The dynamic range due to the need to translate between different frequencies causes problems even with 64-bit integer math. There are overflows and underflows during the intermediate calculation that makes the skew estimate horribly unstable even when the clocks are stable.
This ties to #29569 in that while this is proposed to be in