[ntp:questions] stepping and slewing
Richard B. Gilbert
rgilbert88 at comcast.net
Sun Apr 29 21:25:23 UTC 2007
Riccardo Castellani wrote:
> What is difference among stepping and slewing mode which are used by ntpd ?
> questions mailing list
> questions at lists.ntp.isc.org
Slewing means that ntpd adjusts the clock at a maximum rate of 500
microseconds per second.
Stepping means that the clock jumps abruptly from some incorrect time to
some reasonable approximation of the correct time. In normal operation
ntpd will not step the clock; any error less than 128 milliseonds will
be corrected by slewing the clock. An error of more that 128
milliseconds in considered an abnormal condition!
Since correcting large errors by slewing the clock could take days or
weeks to complete stepping is used but, as mentioned above, this is not
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