Re: [Linuxptp-users] Loss of sync with 25% of CPU load

[Miroslav L. <mli...@re...>]

On Tue, Apr 13, 2021 at 11:36:00AM +0200, Diego García Prieto wrote:
> Kernel version: Linux 4.9.18-rt14-rt14 (a preempt-RT patch)

I don't know much about RT kernels.

> NIC: I210 Gigabit Network Connection - Vendor: Intel corporation - Version:
> 03
> 
> Driver: igb

That NIC and driver are solid in my experience, so I'd suspect an
issue with the system clock.

Check current and available clocksources:
cat /sys/devices/system/clocksource/clocksource0/current_clocksource
cat /sys/devices/system/clocksource/clocksource0/available_clocksource

and try switching to a different clocksource, e.g.

echo hpet > /sys/devices/system/clocksource/clocksource0/current_clocksource

-- 
Miroslav Lichvar