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Subject: Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
From: Lee Revell <rlrevell@joe-job.com>
To: Jesper Juhl <jesper.juhl@gmail.com>
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Date: Thu, 14 Jul 2005 20:15:05 -0400
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On Fri, 2005-07-15 at 02:04 +0200, Jesper Juhl wrote:
> While reading this thread it occoured to me that perhaps what we
> really want (besides sub HZ timers) might be for the kernel to
> auto-tune HZ?
> 
> Would it make sense to introduce a new config option (say
> CONFIG_HZ_AUTO) that when selected does something like this at boot:
> 
> if (running_on_a_laptop()) {
>     set_HZ_to(250);
> }

I don't think this will fly because we take a big performance hit by
calculating HZ at runtime.

Lee