Re[2]: NTPsec reports excessive jitter from GPSD/KPPS SHM

[Nick Burkitt]

Hi Paul, Gary.

So moving the GPS to the end of the file AND keeping noselect is 
redundant?
For my application, I'll always prefer GPS time if it's available, so 
removing noselect and moving it to the end is what I want?

-Nick

------ Original Message ------
From: "Gary E. Miller" <address@hidden>
To: "Paul Theodoropoulos via" <address@hidden>
Sent: 3/10/2020 11:56:46 AM
Subject: Re: NTPsec reports excessive jitter from GPSD/KPPS SHM

> Yo Paul!
>
> On Tue, 10 Mar 2020 11:52:45 -0700
> Paul Theodoropoulos via <address@hidden> wrote:
>
> >  On 3/10/20 11:40, Gary E. Miller wrote:
> >  > Yo Nick!
> >  >
> >  > On Tue, 10 Mar 2020 18:15:27 +0000
> >  > "Nick Burkitt" <address@hidden> wrote:
> >  >
> >  >> I think it's time to stick a fork in this one.
> >  > Almost.  A few things still hanging.
> >  >
> >  > You still have this near the top of your ntp.conf:
> >  >
> >  >      # GPS Serial data reference (NTP0)
> >  >      refclock shm unit 0 refid GPS noselect
> >  >
> >  > It should be after all your other time sources.
> >  Question - if the GPS refclock is noselect, shouldn't that mitigate
> >  the necessity to have it at the bottom of the list?
>
> Yeah, mostly, but many people do not want the GPS refclock to be
> noselect.
>
> For example, if you have a power outage, and on reboot your net is
> still down, then the PPS can not work without another chimer with valid
> seconds.  So your NTP can not get a time.  The GPS can provide the base
> seconds, so avoiding that trap.
>
> RGDS
> GARY
> ---------------------------------------------------------------------------
> Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
> address@hidden  Tel:+1 541 382 8588
>
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