[LEAPSECS] Google, Amazon, now Microsoft

[Poul-Henning Kamp]

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In message <556F0C92.4020509 at edlmax.com>, Brooks Harris writes:

>> You're saying this to the bloke who implemented a prototype adaptive
>> optics solution for the ESO ELT on a plain, unmodified FreeBSD
>> kernel ?
>I didn't know that, very impressive. Is there information anywhere how
>it was done?

I did a presentation at a workshop at ESO in december 2012, the
slides seems to be here:

        https://www.eso.org/sci/meetings/2012/RTCWorkshop/proceedings.html

I'm not sure what the legal status is for deeper info.  You'd have
to ask them for access.  The person to talk to is Nick Kornweibel.

>I bring the RT aspect [...]

The first point here is that commodity *NIX, be it LINUX, FreeBSD 
or something else is often used to pull time into systems, even
if they themselves don't do the RT part.

The other thing to notice is that even if it is not RT in the strict
classical sense, commodity *NIX does things which matter on 
microsecond resolution timescales.  (As for instance the ESO thing).

>The time on Microsoft Azure will be Different by a second, everywhere
>http://www.theregister.co.uk/2015/05/29/windows_azure_second_out_of_sync/
>
>As I said earlier - A) Where did they get this information? B) Is it
>true? C) Is that how Windows is behaving?

A) Ask them.  (M$ probably notified their customers ?)

B) I have no reason to doubt it.  The Reg is usually very good on truth.

C) Probably only in Azure.  Other Windows will probably do the
   usual Windows thing:  Step a second some time later.

-- 
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.