Re: stepping and slewing

but can I define slew rate and step rate ?
Pheraps these parameters are defined inside kernel of o.s. ?
slew rate is always 0.5 ms/sec ?

Where can i find doc. about stepping and slewing ?
----- Original Message -----
From: Richard B. Gilbert
Newsgroups: comp.protocols.time.ntp
To: questions@xxxxxxxxxxxxxxxxx
Sent: Sunday, April 29, 2007 11:25 PM
Subject: Re: [ntp:questions] stepping and slewing


Riccardo Castellani wrote:
> What is difference among stepping and slewing mode which are used by ntpd ?
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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
normal.

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