[ntp:questions] Slow convergence of NTP with GPS/PPS

David J Taylor david-taylor at blueyonder.neither-this-part.nor-this-bit.co.uk
Fri Oct 24 13:20:00 UTC 2008

Richard B. Gilbert wrote:
> And ntpd could take many minutes to bludgeon the local clock into
> submission!  It's easy to determine and set the correct time.  It's
> less easy to determine and set the correct frequency and thus KEEP the
> correct time.

Wasn't the OP looking for about 0.5s accuracy?  Ah, no, that was someone 
else.  Here we're aiming for:

  "Our application requires good time accuracy (better than 5ms) but it 
also needs to get there quickly (as quickly as possible, but ideally 
taking no more than about 15 minutes)."

I would have thought that a GPS and NTP would have been able to achieve 
that, at least with a current drift file.


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