Explore the full engineering blog here: https://engineering.fb.com/2025/02/03/production-engineering/how-precision-time-protocol-ptp-handles-leap-seconds/

This Meta Engineering blog post discusses the challenges of leap seconds in high-precision time synchronization systems, particularly those using Precision Time Protocol (PTP). It explains how Meta addresses leap seconds using a "self-smearing" algorithm within their fbclock library, which adjusts time values in small increments. The article contrasts this approach with the traditional Network Time Protocol (NTP) method and advocates for using International Atomic Time (TAI) over Coordinated Universal Time (UTC) to avoid leap second complications. Ultimately, the authors support eliminating future leap seconds to simplify timekeeping and enhance precision.