Monotonically increasing timestamps?

[axiak]

The timestamp generation at https://github.com/aphyr/meangirls/blob/master/lib/meangirls.rb#L59 fails to be monotonic if the server is running NTP and performs a clock adjustment. Is there a better clock here?

[aphyr]

Yeah, we should use a disk-backed flake time.

[navinp1281]

return Process.clock_gettime(Process::CLOCK_MONOTONIC_RAW)
No intialization etc per system. It works as per the below definition.
I think there is a BSD CLOCK_MONOTONIC_PRECISE but this is from linux.

man clock_gettime
CLOCK_MONOTONIC_RAW (since Linux 2.6.28; Linux-specific)
Similar to CLOCK_MONOTONIC, but provides access to a raw hard‐
ware-based time that is not subject to NTP adjustments or the
incremental adjustments performed by adjtime(3).