I have finally got my RPi NTP server set up referenced to a Thunderbolt PPS. NTP is using the PPS and my stats look good, but when I run     ntpq -c kerninfo my output is:     associd=0 status=0118 leap_none, sync_pps, 1 event, no_sys_peer,     pll offset:            0.00753     pll frequency:         -10.4492     maximum error:         0.012     estimated error:       1e-06     kernel status:         pll nano     pll time constant:     4     precision:             1e-06     frequency tolerance:   500     pps frequency:         0     pps stability:         0     pps jitter:            0     calibration interval   0     calibration cycles:    0     jitter exceeded:       0     stability exceeded:    0     calibration errors:    0 The pps frequency, stability, and jitter are all zero.     dmesg | grep pps and      ppstest /dev/pps0 both indicate the kernel pps support is working. Why isn't the kerninfo showing any info on the pps frequency, stability, and jitter? --Keith

 ntpq -c kerninfo

 associd=0 status=0118 leap_none, sync_pps, 1 event, no_sys_peer,
 pll offset:            0.00753
 pll frequency:         -10.4492
 maximum error:         0.012
 estimated error:       1e-06
 kernel status:         pll nano
 pll time constant:     4
 precision:             1e-06
 frequency tolerance:   500
 pps frequency:         0
 pps stability:         0
 pps jitter:            0
 calibration interval   0
 calibration cycles:    0
 jitter exceeded:       0
 stability exceeded:    0
 calibration errors:    0

 dmesg | grep pps

  ppstest /dev/pps0

Hi Do you have any other inputs into your server? NTP compares the various inputs to come up with things like stability. With nothing to compare to, there is no data to show. Bob > On Jul 6, 2020, at 12:04 PM, Keith E. Brandt, WD9GET <wd9get@amsat.org> wrote: > > I have finally got my RPi NTP server set up referenced to a Thunderbolt PPS. > NTP is using the PPS and my stats look good, but when I run > > ntpq -c kerninfo > > my output is: > > associd=0 status=0118 leap_none, sync_pps, 1 event, no_sys_peer, > pll offset: 0.00753 > pll frequency: -10.4492 > maximum error: 0.012 > estimated error: 1e-06 > kernel status: pll nano > pll time constant: 4 > precision: 1e-06 > frequency tolerance: 500 > pps frequency: 0 > pps stability: 0 > pps jitter: 0 > calibration interval 0 > calibration cycles: 0 > jitter exceeded: 0 > stability exceeded: 0 > calibration errors: 0 > > The pps frequency, stability, and jitter are all zero. > > dmesg | grep pps > > and > > ppstest /dev/pps0 > > both indicate the kernel pps support is working. > > Why isn't the kerninfo showing any info on the pps frequency, stability, and jitter? > > --Keith > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there.

On Montag, 6. Juli 2020 18:04:33 CEST Keith E. Brandt, WD9GET wrote: > Why isn't the kerninfo showing any info on the pps frequency, stability, > and jitter? Kernel support for PPS and for in-kernel PLL utilizing one PPS input are two different things, at least in the Linux kernel. You are unlikely to have the in-kernel PLL support compiled in unless you are on older / exotic hardware or have compiled your own kernel with the requisite configuration changes. The in-kernel PLL is not compatible with the tickless scheduler model that most modern platforms use to enable energy-efficient operation. When you try toi switch the kernel PLL on in the NTP configuration you should see an error reported in the logs when ntpd starts. Regards, Achim. -- +<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+ Factory and User Sound Singles for Waldorf Blofeld: http://Synth.Stromeko.net/Downloads.html#WaldorfSounds