Binary package “adjtimex” in ubuntu bionic

kernel time variables configuration utility

 This package provides a utility to manipulate the kernel time
 variables. For a machine connected to the Internet, or equipped with
 a precision oscillator or radio clock, the best way to keep the
 system clock accurate is using NTP (Network Time Protocol). However,
 for a standalone or intermittently connected machine, you may use
 adjtimex instead to at least correct for systematic drift. It can
 optionally adjust the system clock using the CMOS clock as a
 reference, and can log times for long-term estimation of drift rates.