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How often does the NTPD service update system clocktime by default?

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up vote 4 down vote accepted

On most systems, including Linux, unless the clock is very off, ntpd doesn't set the clock, it instead varies the length of a second, so that the clock slowly becomes into sync with the master.

This is calling clock skewing, and it's beneficial because it's usually better for a second to be slightly wrong than for seconds to be missed, or even worse, redone.

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Very well written. Thanks. – Mike B Oct 10 '12 at 21:48

It's also worth noting that if a clock is really off, NTP will refuse to do anything.

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