linux-kernel - Re: [RFC] exponential update_wall

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <Pine.LNX.4.64.0609282254450.6761@scrub.home>
Date:	Thu, 28 Sep 2006 23:01:25 +0200 (CEST)
From:	Roman Zippel <zippel@...ux-m68k.org>
To:	john stultz <johnstul@...ibm.com>
cc:	lkml <linux-kernel@...r.kernel.org>, Ingo Molnar <mingo@...e.hu>,
	Thomas Gleixner <tglx@...utronix.de>,
	Andrew Morton <akpm@...l.org>
Subject: Re: [RFC] exponential update_wall_time

Hi,

On Wed, 27 Sep 2006, john stultz wrote:

> > You have to keep in mind that ntp time is basically advanced in 1 second 
> > steps (or HZ ticks or freq cycles to be precise) and you have to keep that 
> > property. You can slice that second however you like, but it still has to 
> > add up to 1 second. Right now we slice it into HZ steps, but this can be 
> > rather easily changed now.
> 
> Right off, it seems it would then make sense to make the ntp "ticks" one
> second in length. And set the interval values accordingly.
> 
> However, there might be clocksources that are incapable of running
> freely for a full second w/o overflowing. In that case we would need to
> set the interval values and the ntp tick length accordingly. It seems we
> need some sort of interface to ntp to define that base tick length.
> Would that be ok by you?

I don't see how you want to do this without some rather complex 
calculations. I doubt this will make anything easier.

bye, Roman
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/