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Date: Fri, 26 Mar 2010 17:53:50 +0200
From: Andriy Gapon <avg@icyb.net.ua>
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Cc: freebsd-hackers@FreeBSD.org
Subject: Re: periodically save current time to time-of-day hardware
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on 26/03/2010 17:44 Dag-Erling Smørgrav said the following:
> Andriy Gapon <avg@icyb.net.ua> writes:
>> What do you think about the following patch or something similar?
> 
> I've wondered for years why we didn't already do this.
> 
>> Also, I am aware that the period should be configurable (sysctl).
> 
> Why?

Because there would always be someone who would want a different value :)

> Although I can see an argument for a sysctl to turn it on or off.

Good idea.

> IIRC, Linux saves the clock at shutdown, and every 11 minutes if and
> only if the system clock is synchronized to an external reference.

Both are good ideas too.
I know how to add a shutdown hook (event handler), but I don't know how to check
if time synchronization is taking place.

-- 
Andriy Gapon