Peter Roozemaal <[EMAIL PROTECTED]> wrote:
> Tim Shoppa wrote:
> > Peter Roozemaal <[EMAIL PROTECTED]> wrote:
> >> There won't be a convergence to a stable set of 4 servers if you
> >> throw out one of them on a daily basis. You are not even guaranteed
> >> to get a single stable server. Consider having 5 "optimal" peers,
> >> all at the same nearby provider; each of those servers alternately
> >> spend 1 day in the global pool and gets swamped by ntpdate bursts
> >> during the day.
> > 
> > Does that really happen - "good" servers getting swamped and thrown 
> > out regularly?
>
> If the one server in the global pool is 0.5 ms worse than the three
> other servers in the auto-selecting client, it will get thrown out.

Yeah, but that has nothing to do with getting thrown out of pool.ntp.org
service. ntpd can be as picky as it wants (and should be). And nobody
should take it personally when they're 0.5ms off through somebody
else's network connection.

Obviously you guys are using some really super hyper sensitive measure
of "swamped" and "stable" that is completely out of whack with my
worldview.

> > I'm not saying that there aren't clients that have stupid patterns 
> > for asking for time, but they only hurt other similarly stupid
> > clients so I don't see that as fundamental.
>
> Stupid clients may interfere with the upstream requests of their
> servers. IP packets get buffered in routers and at the server. More
> buffering means more jitter, less accuracy.
> I have offsets and jitters in the order of a milisecond over my ADSL
> link. It also takes about a milisecond to put a single NTP packet out on
> the ADSL link.

That's much closer to my worldview- that offsets and jitters in the
low milliseconds are wonderful and do not represent any sort of
problem. I mean, I have a real skinny network pipe, and I never ever
see it getting jammed up with NTP requests in the catastrophic ways
everyone here is talking about. NTP traffic quantities are so obscurely tiny
in the grand scheme and if some bozos all ask for the time at the same time,
that doesn't hurt anyone else who is asking at other times.

Tim.
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