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

Hal Murray hal-usenet at ip-64-139-1-69.sjc.megapath.net
Mon Oct 27 17:13:45 UTC 2008


>That was what he said "worst case initial error" He should have said
>127.999msec though I think:-)
>
>Actually it is NOT the worst case scenario. Try  a drift which is seriously
>off instead. That takes much longer to settle down. First ntp has to notice
>that the drift is off, and then has to start correcting it. Thus a drift of
>say 200PPM (500 would be a worst case, but ntp cannot correct a 500PPM
>drift so there is no point in going there) will take quite a bit longer to
>correct (should take about twice as long to first go through zero).

I think the worst case drift error is 2*500 PPM.  You can have -500 in the
drift file when the value should be +500.

-- 
These are my opinions, not necessarily my employer's.  I hate spam.




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