nanog mailing list archives
Re: F-ckin Leap Seconds, how do they work?
From: Saku Ytti <saku () ytti fi>
Date: Tue, 3 Jul 2012 21:42:57 +0300
On (2012-07-03 19:33 +0100), Nick Hilliard wrote:
Google's approach to this is interesting:http://googleblog.blogspot.ie/2011/09/time-technology-and-leaping-seconds.html
Yes. I'm sure this is good enough for most people, most people don't need precise time but virtually everyone needs monotonic time. And this is easy to deploy TAI + UTC presentation using leapsecond file lookup isn't exactly easy. Too bad this isn't standard configuration option in NTPd. Also one thing I wonder, why did GOOG choose to skew in just 24h, why not the moment leap is announced? Everyone has some accuracy budget, what ever that might be, it almost certainly is same every day. So you could live with tighter accuracy budget the longer you spend skewing. PC clock on average is probably like 15PPM accurate (or order magnitude of worse, IBM servers seem to be exception). If you'd skew 3 months, your skewing would cause inaccuracy of 0.19PPM. Skewing in single day causes inaccuracy of 11.6PPM (still almost certainly better than free-running PC oscillator) -- ++ytti
Current thread:
- Re: F-ckin Leap Seconds, how do they work?, (continued)
- Re: F-ckin Leap Seconds, how do they work? Steve Allen (Jul 04)
- Re: F-ckin Leap Seconds, how do they work? Scott Howard (Jul 04)
- Re: F-ckin Leap Seconds, how do they work? Dave Hart (Jul 05)
- Re: F-ckin Leap Seconds, how do they work? Peter Lothberg (Jul 05)
- Re: F-ckin Leap Seconds, how do they work? Saku Ytti (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? valdis . kletnieks (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Saku Ytti (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Owen DeLong (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Saku Ytti (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Nick Hilliard (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Saku Ytti (Jul 03)
- RE: F-ckin Leap Seconds, how do they work? Keith Medcalf (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Tony Finch (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Owen DeLong (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Saku Ytti (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Peter Lothberg (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Peter Lothberg (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Tony Finch (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Owen DeLong (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Chris Adams (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Jay Ashworth (Jul 03)