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>> I have not looked closely at ntimed but I have little doubt it is high-quality work, probably as good as anything I am capable of producing, possibly better.

Ok, that is just precious. =) One is a kernel hacker and time-nuts regular with one of the world's most precise clocks in his home, and the other recently wrote:

> There’s a longstanding legend that only Dave Mills ever really understood the Byzantine time-synchronization algorithms at NTP’s heart, but I used to be a mathematician and I think I already get most of it outside of a few arcana about statistical filtering of noisy signals.

From a purely technical standpoint, I know who I'd bet my money on.

By the way, phk recently mentioned that he was getting back into ntimed, so fingers crossed that we get two safe and correct NTP alternatives in the observable future.

https://twitter.com/allanjude/status/635635386832715777

3 comments

While he said as of August 23rd that he's agin working on ntimed, that's not reflected in GitHub updates: https://github.com/bsdphk/Ntimed

And it bears mentioning that ESR has been working on GPSD for more than a decade (a daemon to extract accurate time from GPS receivers), and he sure sounds math literate to my not entirely untutored ears in various discussions over the years.

Given the well known curse of total rewrites, which I've experienced myself, I too know who I'd bet my money on.

> "he sure sounds math literate"

This is the standard ESR parlor trick. Eric took several courses in math and philosophy at the University of Pennsylvania.

http://poynder.blogspot.com/2006/03/interview-with-eric-raym... "As a freshman at the University of Pennsylvania Raymond was immediately marked out as a potential math prodigy. Having found school insufficiently stretching for his above average talents, however, he lacked the necessary discipline or emotional maturity to cope with the demands of an undergraduate course, and after suffering a "math burnout" left without a degree."

I'd put my money on phk. Every. Time.

Saying that GPSD is "a daemon to extract accurate time from GPS receivers" is a little misleading. GPSd primary function is to make "data on the location/course/velocity of the sensors available to...the host computer." It also has functionality to share data with ntpd but timekeeping is certainly not the primary purpose.

> ESR has been working on GPSD for more than a decade

Timekeeping and location calculation is very easy to do clean sheet. That is, until you start to hit corner cases and exceptions and the realities of physical real world inputs like jitter and offset and dispersion (and those are just the grit that ntpq tells you about) and all the crud humans made up like leap seconds and calendrical calculations.

My money's on the guy who's been blowing the grit out of the machine.

Oh, certainly. But from what I've followed of this project, that part of nntpd is, while complicated, healthy and neither needs serious modification nor is slated for much more than maybe adding tests. It's the huge pile of cruft that accumulated around the core that's getting worked on, or simply removed.

...precious.

Sure, ESR is kind of silly, but I don't understand the animus here on HN. ISTM he isn't making anything worse. Somebody wanted NTP "Classic" improved, and they decided to pay ESR to do it. It's not as though his patches or those of his collaborators would have been incorporated into ntimed anyway. Maybe some people think that work like this should only be done by a PhD with the approval of a committee of PhDs. ESR has been pretty consistent in all his voluminous writings, that he does not agree with that development philosophy.

However I sympathize with everyone in this thread who runs ntpdc on his Lisp machine.

Look, all things considered I like that we have someone like esr. He's an important figure in the history of software engineering. Whatever my opinion of his software output might be, that doesn't affect his impact a bit.

But the man's writing - and that statement in particular - is just so pompous. And here of all cases we have two opposites colliding. One is a world-class expert on the topic in question, NTP, and the other is a world-class self promoter. So when esr says that Kamp might `possibly produce something better` than him while working on an ntpd successor, I can't help but smile. =)

> one of the world's most precise clocks in his home

Seriously? More precise than the clocks in national labs that contribute to the derivation of UTC? (USNO, NRL, NIST, NPL, NRC, etc) I don't think that is a claim phk has ever made and I am not sure why you are making it for him.

phk has a Stanford Research Systems PRS10 Rubidium Frequency Standard (0 MHz rubidium oscillator)<http://www.thinksrs.com/products/PRS10.htm> at his home. Serial # 005597. The short-term stability of this unit is about 5 × 10-12

This particular PRS10 is GPS referenced _and_ drives one of his GPS referenced NTP servers.

He also has (or had) an array of 10 Motorola Oncore UT+ or M12+T GPS receivers sitting on a row 20cm apart, mounted on a shed roof.

UTC(USNO) is provided by the USNO Reference System #2 (Master Clock #2), which is a Datum Inc. hydrogen maser http://tycho.usno.navy.mil/maser.html

The frequency stability "sigma" of MC #2 has been < 2 x 10-15 during the last year.

NIST-F1, the nation's primary time and frequency standard, is a cesium fountain atomic clock developed at the NIST laboratories. The uncertainty of NIST-F1 is continually improving. In 2000 the uncertainty was about 1 x 10-15, but as of January 2013, the uncertainty has been reduced to about 3 x 10-16

So, no, not "more precise" than the clocks you list, but how many of us have a Rubidium standard in our home?

(And when compared to the large number of clocks in the world, yes, I think that the PRS10 is "one of the most precise".)

So more precise than all of the clocks in the world once you exclude "the most precise clocks in the world"? Yes, MC#2 is a hydrogen maser clock. But you failed to mention that it is driven by an ensemble of 41 clocks, 4 rubidium fountains, 19 hydrogen masers, and 18 5071 cesiums. And if we are talking about NIST-F1, don't forget F1's new friend, NIST-F2, that is three times as accurate and soon enough the Italians will have there very own version IT-CsF2. And then there are the lattice clocks from JILA...

Welcome, fellow time geek.

"One of the most..." doesn't mean "the most". It means there is a group of "the most", which can include a large raw number of objects, but this number is still a tiny fraction of the overall number of things, and his is in that group. It could be the last one in that group, but still in that group. Saying "The united states is one of the most populous nations on earth" doesn't mean it's more populous than China or India, simply that it is up in that rarified group of "mosts".

My bad, I wasn't completely precise. The claim is he has one of the most precise NTP clocks, which was relevant to this discussion.

https://queue.acm.org/detail.cfm?id=2716278 (Ctrl-F 'precise')