[Ntp] Wtrlt: NTv5 and polling interval

Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de> Wed, 14 April 2021 07:11 UTC

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Date: Wed, 14 Apr 2021 09:11:32 +0200
From: "Ulrich Windl" <Ulrich.Windl@rz.uni-regensburg.de>
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Subject: [Ntp] Wtrlt: NTv5 and polling interval
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Sorry, the first address was undeliverable, so I'm trying this one.

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Hi!

I feel there's an issue with NTPv4 and the polling interval (see attached image):
After a host reboot, the polling interval goes up while "the sync" is not stable yet, so it goes down again, then going up again, etc.
Maybe the polling interval is going up too early and going down too late.
(In the graph you also see some "micro clock hopping effect" that I really couldn't tame in the LAN)
I'm attaching another graph that shows that clock hopping in more detail.

It would be great if those issues could be addressed in NTPv5.

Regards,
Ulrich



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