leap smearing

Tags: clocks (distributed systems)

https://developers.google.com/time/smear

• google smears the leap second before and after each leap

https://googleblog.blogspot.com/2011/09/time-technology-and-leaping-seconds.html https://docs.ntpsec.org/latest/leapsmear.html https://packetpushers.net/ntp-leap-smearing-what-is-it/ https://developers.redhat.com/blog/2015/06/01/five-different-ways-handle-leap-seconds-ntp/ https://xkcd.com/2266/ Burnicki, “Leap Second Smearing with NTP.”

Questions

• do emergency alert systems (EAS) use internet timing?
• what systems failover to internet timing?
• what services actually rely directly on gps?
  • https://ilrs.gsfc.nasa.gov/docs/timing/gpsrole.pdf

Facebook wants to remove leap smearing by removing the leap second entirely

• https://engineering.fb.com/2022/07/25/production-engineering/its-time-to-leave-the-leap-second-in-the-past/