Re: 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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