Hi Miroslav, > Verify that the process which syncs the system clock on start from the > external RTC doesn't do that again later. Other than that I have no > idea what could be wrong. System time is updated with RTC once and when 3D fix is received, system time is corrected to GPS time using Chronyd (as I am sending the GPS time using Unix Domain Socket to chrony. Chronyd uses PPS as a trusted source). The chronyc sources output shows large offset in milliseconds during the first 3 samples.
One clarification on another item related to Chronyd: - I am using the makestep directive (which does continuously if the difference is more than 100ns) in the config file. Does chronyd adjusting the system time affects the CLOCK_MONOTONIC as well? Thanks & Regards Sarveshwar.K On Tue, May 9, 2023 at 12:45 PM Miroslav Lichvar <[email protected]> wrote: > On Mon, May 08, 2023 at 12:09:16PM +0530, sarveshwar k wrote: > > Hi Miroslav, > > > > My Implementation is as below: > > - We have external RTC, which is used to sync system time on > initialization > > based on 1PPS from external RTC > > - And on receiving GNSS 3D fix, the GPS UTC time is sent to chrony over > > Unix Domain Socket. > > - And we sync RTC for every 10 seconds on GNSS 1PPS (so that RTC is close > > to the UTC time in seconds) > > > Can you please support on debugging what can be the issue. > > Verify that the process which syncs the system clock on start from the > external RTC doesn't do that again later. Other than that I have no > idea what could be wrong. > > -- > Miroslav Lichvar > > > -- > To unsubscribe email [email protected] > with "unsubscribe" in the subject. > For help email [email protected] > with "help" in the subject. > Trouble? Email [email protected]. > >
