[ntp:questions] Re: ntpd and leap seconds on Windows

Arthur.Porkchop at exemail.com.au Arthur.Porkchop at exemail.com.au
Thu Oct 13 06:42:16 UTC 2005

Perhaps I misunderstand, but on Unices which implement David Mill's
kernel timekeeping model, on the day of a leap second, ntpd sets a flag
in the kernel advising that a leap second has to be inserted. The
kernel clock then adds/deletes a second as necessary at the appropriate
time. You can see the state machine that handles this in Linux in
kernel/timer.c; this is all described in section 3.3 of David Mill's "A
Kernel Model for Precision Timekeeping".

My question was whether Windows implements the leap second state
machine, and if not, whether the Windows port of ntpd tries to work
around this by forcing a step shortly after the leap second.

Michael Wouters.

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