[177497] in North American Network Operators' Group
Re: REMINDER: Leap Second
daemon@ATHENA.MIT.EDU (Joe Klein)
Sun Jan 25 16:17:44 2015
X-Original-To: nanog@nanog.org
In-Reply-To: <20150125172627.GM24849@sizone.org>
Date: Sun, 25 Jan 2015 16:17:33 -0500
From: Joe Klein <jsklein@gmail.com>
To: Ken Chase <math@sizone.org>
Cc: nanog@nanog.org
Errors-To: nanog-bounces@nanog.org
I spoke on time hacking and ntp 3 years ago at shmoocon.
On Jan 25, 2015 12:28 PM, "Ken Chase" <math@sizone.org> wrote:
> I think devices would likely be fine, unless they're concerned with
> reconciling
> a leap-second updated ntp source and one that's not. Who wins?
>
> For most NTPs I would guess they're slaves to whatever feed and just
> 'believe'
> whatever they're told. (Sounds like a security hole waiting for high
> frequency
> trader types, q.v.
>
> http://www.theverge.com/2013/10/3/4798542/whats-faster-than-a-light-speed-trade-inside-the-sketchy-world-of
> )
>
> Can't we just subscribe to a leapsmeary NTP feed if we care to have no
> big leap (I dont mind)? Isnt NIST offering this?
>
> /kc
>
>
> On Sun, Jan 25, 2015 at 06:01:40PM +0100, Karsten Elfenbein said:
> >Hi,
> >
> >Java had some issues with 100% CPU usage when NTP was running during
> >the additional second in 2012.
> >
> http://blog.wpkg.org/2012/07/01/java-leap-second-bug-30-june-1-july-2012-fix/
> >
> >Google did something different to get the extra second in:
> >
> http://googleblog.blogspot.de/2011/09/time-technology-and-leaping-seconds.html
> >
> >Most devices probably don't even know about the leap second coming as
> >that would require a firmware upgrade.
> >
> >
> >Karsten
> >
> >2015-01-25 16:19 GMT+01:00 Mike. <the.lists@mgm51.com>:
> >> On 1/25/2015 at 9:37 AM Jay Ashworth wrote:
> >>
> >> |This June 30th, 235959UTC will be followed immediately by 235960UTC.
> >> |
> >> |What will /your/ devices do?
> >> =============
> >>
> >>
> >> I've always wondered why this is such a big issue, and why it's done
> >> as it is.
> >>
> >> In UNIX, for instance, time is measured as the number of seconds
> >> since the UNIX epoch. imo, the counting of the number of seconds
> >> should not be "adjusted", unless there's a time warp of some sort.
> >> The leap second adjustment should be in the display of the time,
> >> i.e., similar to how time zones are handled.
> >>
> >>
> >> fwiw
> >>
> >>
> >>
>
> --
> Ken Chase - math@sizone.org Toronto
>
