[ntp:questions] Speed of ntp convergence
David J Taylor
david-taylor at blueyonder.neither-this-part.nor-this-bit.co.uk
Sat Nov 1 21:32:06 UTC 2008
> Nope, it is not my "ssytem" if by that you mean my computer. The
> convergence is a beautiful exponential convergence with a time scale
> of 1
> hour almost exactly. That is not hardware. That is the software ntp
Just along the lines that if my system converges in 10 minutes, I am at a
loss to see why yours takes ten hours. It seems to me that there is
nothing inherently wrong with the NTP version I have.
> Try switching it off, changing the value int he drift file by say
> 50PPM and
> then switching it on again, and see how long it takes to recover from
Why would I do that? The drift values rarely change by more than five,
certainly not by 50. If you are seeing a change of 50, then perhaps that
it part of your problem?
> Note, if you are running gps, why have a poll level 6? The
> for ref- clocks is poll level 4?
Probably because the system is also polling Internet servers, and I didn't
want to hammer them at 16 second intervals. It seems that the Internet
poll interval /must/ be the same as the ref-clock poll interval, and that
it doesn't automatically adjust upwards (which would be nice).
Where did you get your information from, by the way? I found this:
"For most directly connected reference clocks, both minpoll and maxpoll
default to 6 (64 s)."
from a quick Google search, but I don't know if that's in the official
More information about the questions