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Subject: Re: [PATCH] i386: Selectable Frequency of the Timer Interrupt
From: Lee Revell <rlrevell@joe-job.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: Linus Torvalds <torvalds@osdl.org>,
       dean gaudet <dean-list-linux-kernel@arctic.org>,
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Date: Thu, 14 Jul 2005 10:55:40 -0400
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On Thu, 2005-07-14 at 10:38 +0200, Ingo Molnar wrote:
>  - there are real-time applications (robotic environments: fast rotating
>    tools, media and mobile/phone applications, etc.) that want 10
>    usecs precision. If such users increased HZ to 100,000 or even
>    1000,000, the current timer implementation would start to creek: e.g.
>    jiffies on 32-bit systems would wrap around in 11 hours or 1.1 hours.
>    (To solve this cleanly, pretty much the only solution seems to be to
>    increase the timeout to a 64 bit value. A non-issue for 64-bit
>    systems, that's why i think we could eventually look at this 
>    possibility, once all the other problems are hashed out.)
> 

Those types of systems will not be 64 bit for many, many years, if
ever...

Lee