[ntp:questions] Leap second bug?

David Malone dwmalone at maths.tcd.ie
Sat Jan 5 10:30:28 UTC 2008

"David L. Mills" <mills at udel.edu> writes:

>The intended behavior if the servers do correctly signal a leap and the 
>kernel is unaware of that, is that the step interval will be exceeded 
>for about 15 minutes and then the time will be stepped. During that 
>interval your clock will appear one second slow relative to the server 
>that has correctly inserted a second. There will be no slew, onlly the 
>step. The fact that your time showed otherwise suggests either the step 
>has been disabled or something else comes unstuck. Our clocks here 
>showed no such behavior as yours.

During the 2005 leap second, I did see some of our peers show an
offset of 0.5 seconds for reasons that I don't understand.  For
example, see the last graph on this page:


It wasn't the only example - several other peers showed an offset
of near 0.5 seconds after the leap - you can find those through the
"more graphs of other peers" link at the bottom of the page.


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