[LEAPSECS] My FOSDEM slides

[Steve Allen]

On Wed 2015-03-04T08:54:00 -0500, Joseph Gwinn hath writ:
> >> On Thu, 26 Feb 2015 15:09:01 +0100, Martin Burnicki wrote:
> > I think I'll give it a try soon. I'd expect that a negative leap
> > second might work if an appropriate announcement is received from a
> > refclock or upstream NTP server, but it will be interesting to find
> > out if this works with a NIST-style leap second file where the TAI
> > offset decreases at a given date.
>
> Hell - lots of code can't handle a positive leap second, so what hope
> is there?

There's a lot of hope for negative leap seconds to be inconsequential
to a lot of code.

An overloaded operating system which is timesharing may suspend a
process for a long time, so when that process wakes up it may find
that it has missed a second.  A virtual machine running on a cloud
server farm in Oregon may be saved to disk, shipped across the
continent to North Carolina, and restarted over a second later -- or
kept on disk and replicated and restarted even later, multiple times.

What happens with a negative leap second is a lot like what happens to
non-real-time processes and machines as a routine part of operation.

--
Steve Allen                 <sla at ucolick.org>                WGS-84 (GPS)
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