[ntp:questions] Keeping NTP Honest Redux

David J Taylor david-taylor at blueyonder.not-this-bit.nor-this.co.uk.invalid
Sat Nov 7 08:22:04 UTC 2009

"Evandro Menezes" <evandro at mailinator.com> wrote in message 
news:d9a76148-a9c9-45d5-ac72-4e7588c61cca at m7g2000prd.googlegroups.com...
> I've come to the conclusion that since NTP doesn't correct for
> temperature variations, it's long-term compensation is counter-
> productive.  Therefore, instead of letting the poll period increase to
> the default 1024s, perhaps it'd be best to limit it to 64s.  However,
> this requires that each server has the option maxpoll attached to it.
> It'd be more convenient to have set this parameter for all servers
> from a single place, such as the old tinker maxpoll option.
> So, why was tinker maxpoll removed?  Any chance to get it back in?

What sort of accuracy are you wanting, and what OS are you running?  You 
could add a local stratum-1 server with a GPS source if you are after 
really good performance, or you could lock your PCs to one local system 
with 64s poll and have that system sync over the Internet with the default 
automatic poll.  Some public servers may consider excessive polling to be 
an attack and disconnect you.

Here is what you can get with a Garmin GPS 18x LVC puck and Windows-7 (an 
OS not known for its timekeeping).  Use FreeBSD and you would likely get 
at least ten times better:

A Windows XP system synced to that stratum-1 PC shows these temperature- 
and load-related variations:


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