[ntp:questions] Meinberg software running under Vista/Windows 2008

Steve Kostecke kostecke at ntp.org
Thu Jul 7 03:16:18 UTC 2011


On 2011-07-06, Chris Albertson <albertson.chris at gmail.com> wrote:
> On Wed, Jul 6, 2011 at 2:59 PM, David Woolley
><david at ex.djwhome.demon.invalid> wrote:
>
>>> I found it.
>>> http://www.eecis.udel.edu/~mills/ntp/html/clock.html
>
>> For a persistent offset of more than 128ms, ntpd will remove the whole
>> offset in one go.  This will be after the 15 minute delay and subsequently
>> finding multiple samples showing an acceptably low jitter.
>
> So what did I miss when I read the above link?

Where in this does it state that steps are only 125ms ?

| Step and Stepout Thresholds
| 
| Under ordinary conditions, the clock discipline gradually slews the
| clock to the correct time, so that the time is effectively continuous
| and never stepped forward pr backward. If, due to extreme network
| congestion, an offset spike exceeds the step threshold, the spike is
| discarded. However, if offset spikes greater than the step threshold
| persist for an interval more than the stepout threshold, the system
| clock is stepped to the correct time. In practice, the need for a step
| has been extremely rare and almost always the result of a hardware
| failure or operator error. The step threshold and stepout thresholds
| default to 125 ms and 300 s, respective, but can be changed with the
| step and stepout options of the tinker command, respectively. If the
| step threshold is set to zero, the step function is entirely disabled
| and the clock is always slewed. The daemon sets the step threshold to
| 600 s using the -x option on the command line. If the -g option is used
| or the step threshold is set greater than 0.5 s, the precision time
| kernel support is disabled.

[snip: 2 paragraphs which don't discuss the threshold]

-- 
Steve Kostecke <kostecke at ntp.org>
NTP Public Services Project - http://support.ntp.org/




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