UEK 4.1.12-124.27.1 - time drift - offset - tsc. vs. hpet - Intel Skylake Xeon

May 29, 2019 10:32AM

Upgrading from previous UEK kernel to current brought our system into time drift trouble.

Current installed kernel:

uname -a

4.1.12-124.27.1.el7uek.x86_64 #2 SMP Mon May 13 08:56:17 PDT 2019 x86_64 x86_64 x86_64 GNU/Linux

The systems time drifted by 2 seconds per 10 minutes as seen in the monitoring of the systems NTP service (as seen in the graphic):

Changing the clock source of the system seems to fix the problem as NTP time offset now normalized (Current time 16:10).

Before 15:10:

root@system # cat /sys/devices/system/clocksource/clocksource0/current_clocksource

tsc

After 15:10:

root@system # echo hpet > /sys/devices/system/clocksource/clocksource0/current_clocksource

root@system # cat /sys/devices/system/clocksource/clocksource0/current_clocksource

Linux Operating System (MOSC)