[LEAPSECS] Google, Amazon, now Microsoft
phk at phk.freebsd.dk
Sun May 31 16:49:19 EDT 2015
In message <556B6735.20784.5A32D16B at dan.tobias.name>, "Daniel R. Tobias" writes
>On 31 May 2015 at 19:33, Poul-Henning Kamp wrote:
>> Most likely, at some random time after the leapsecond, your clock
>> steps a second.
>...which is basically how most computers deal with time
>synchronization, excepting the minority that actually attempt
>continuous high precision and accuracy; the computer's clock, not all
>that accurate a timepiece, drifts off from external standards within
>the period (hours, days, weeks) between synchronizations, and has to
>step a few seconds one way or the other to catch up (possibly
>smoothed out to prevent discontinuities that harm processes in
>progress); the leap second, if any, is lost in the noise.
I have no idea what kind of computers you are talking about here,
but your description has very little to do with the computer where
You may be right for the typical kids game-computer and the computer
in your set-top-box, and for such purposes I doubt leap seconds are
going to wreck havoc.
I'm talking about "work computers" (and so is Microsoft Azure) and
here timekeeping matters, because otherwise emails are after the
replies to them, databases don't agree about stock, medicine does
not live up to FDA rules etc. etc. etc.
In this world, NTP rules, PTP is the up and coming kids where
it really matters, and leap-seconds are not at all lost in
The big problem here, is that we have lost a generation of good
IT-people to the dot-com period, and they think, like you
seem to think, that "What Me Worry?".
 Although, if all Playstations and X-Boxes suddenly go into a
full CPU-spin at the same time, that might tilt certain weaker
 The IT profession grew by a factor of about 1000 during the
dot-com years. Everybody who could sit still in front of a keyboard
and read an O'Really? book was suddenly a web-programmer. It is
probably historys greatest dumbing down of any trade - ever - and
we're still spending a lot of our energy educating these people.
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG | TCP/IP since RFC 956
FreeBSD committer | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.
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