[ntp:questions] NTP with GPS and RTC

David Taylor david-taylor at blueyonder.co.uk.invalid
Fri Apr 26 18:53:35 UTC 2013

On 26/04/2013 19:09, unruh wrote:
> Yes, this is important. You need 5-10 hours of connection for ntpd to
> settle down to its "best" timekeeping.

I don't see that here.  With a local PPS reference you get within a few 
microseconds within an hour.  If the precision needed is less than that, 
say within a hundred microseconds, that's achieved within minutes on 
FreeBSD or Linux systems.  If you are after microseconds, you should use 
a local PPS source, not rely on purely Internet connections.

There are a number of parameters you can play with within NTP, primarily 
the poll interval, to make the response to changes faster, so you can 
optimise NTP to the environment you have and the accuracy you need.
Web: http://www.satsignal.eu

More information about the questions mailing list