[ntp:questions] how do I lock in average frequency correction

Dave Hart davehart at gmail.com
Mon Feb 13 07:30:39 UTC 2012

On Sun, Feb 12, 2012 at 17:36, unruh <unruh at invalid.ca> wrote:
> Uh, that is what ntp tries to do, and is why it shifts up its poll
> interval as time goes along ( and since it throws away 80% of
> measurments, the effective poll interval is about 8 times as long as the
> actual poll interval).

s/effective poll interval/time constant/

That up to 8 x poll time constant is accounted for in the design.
There is no bug here.  In fact, while you harp endlessly on this
point, it's due to the IMHO brilliant minimum delay clock filter which
very effectively sifts signal out of noise.  ntpd is not going to rip
out the clock filter so it can whip around tracking noise as quickly
as possible.  Please find somewhere else to relieve your bowels.

Dave Hart

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