[ntp:questions] very slow convergence of ntp to correct time.

Unruh unruh-spam at physics.ubc.ca
Sat Jan 19 06:36:45 UTC 2008

In trying to figure out whether it is chrony or the machine which is
causing the oscillations in the rate on my systems, I decided to switch one
to ntp. That system was withing 10usec of the "correct" time ( ie the time
as desgnated by a GPS driven computer withing about 150usec roundtrip
network distance). ntp started up and the offset steadily climbed until it
was 60msec (not usec) offset. At that point finally ntp started to do
something   and
gradually brought the offset down. Now, three hours later it is still
14msec (1000 times worse than it started out as) offset and has settled
down there. 
loopstats says that the timescale is now a 9 ( which I guess is 500 sec--
10 min) while the clock still sits there 14 msec away from the correct
time with little evidence of the offset decreasing.
  While I can understand the desire to have
long integration constants, but surely the convergence to the correct time
( or rather say +- 10usec, not 10ms from correct time) should be a bit
faster than this.

Is there some problem in ntp?

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