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Re: [Ntp] Antw: Re: Antw: [EXT] Re: CLOCK_TAI (was NTPv5: big picture)

Martin Burnicki <martin.burnicki@meinberg.de> Mon, 11 January 2021 10:06 UTC

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To: Hal Murray <hmurray@megapathdsl.net>, Ulrich Windl <Ulrich.Windl@rz.uni-regensburg.de>
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From: Martin Burnicki <martin.burnicki@meinberg.de>
Organization: Meinberg Funkuhren GmbH & Co. KG, Bad Pyrmont, Germany
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Subject: Re: [Ntp] Antw: Re: Antw: [EXT] Re: CLOCK_TAI (was NTPv5: big picture)
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Am 11.01.21 um 08:48 schrieb Hal Murray:
> 
> Ulrich.Windl@rz.uni-regensburg.de said:
>> Why not a week before and a week after? I mean there are many arguments for
>> and against different intervalks. 
> 
> It has to be long enough and the transition from normal-to-smear gentle enough 
> so that ntpd will follow the smearing servers.  As long as the interval is 
> long enough, how long doesn't matter.  The big boys agreed on a number.  There 
> is no reason to pick a different one.

Right.

On the one hand, it has to be long enough that clients can easily follow
the changing clock frequency from the server, but on the other hand, the
smeared time is off the real current time during the smear interval, so
you want an interval as short as possible.

Finally, the length of the smear interval has to be a compromise.


Martin
-- 
Martin Burnicki

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