[tz] Leap seconds in the news

Paul Eggert eggert at cs.ucla.edu
Tue May 19 19:12:30 UTC 2015

Amazon is smearing their clocks for 12 hours each side of this June's 
leap second, so that the clocks will run smoothly but will be 0.5 s off 
when the leap second is inserted.  This affects only their management 
console and backend systems; user EC2 instances are expected to do the 
usual NTP dance.  See:

Clarke G. Amazon cloud to BEND TIME, exist in own time zone for 24 
hours. The Register 2015-05-19. 

This is similar to the leap smear that Google has been doing since a 
2005 leap second hit some of their servers, and the WSJ article says 
that financial markets in Japan, South Korea and Australia are also 
doing different variants of leap smear.  Although leap smear ought to be 
standardized (why would people want to dilute differently in different 
countries or companies?), a previous attempt at standardization didn't 
take.  See:

Kuhn M. UTC with Smoothed Leap Seconds (UTC-SLS). 2011-09-16. 

A higher-tech approach to deal with leap seconds would be to launch 
yourself into space at sufficient velocity so that when you return, 
relativistic time dilation would cause your POSIX clock to match an 
earthbound UTC clock.  Unfortunately this requires time travel one 
second into the future, whereas the current human record-holder, Sergei 
Krikalev, has traveled only 23 ms into the future, and it took him 803 
days' worth of orbiting to do it. See:

Cule M. The Future: Time Travel. Quite Interesting 2008-04-25. 

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