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From: Mark Salisbury <mbs@mc.com>
To: Andi Kleen <ak@suse.de>
Subject: Re: No 100 HZ timer !
Date: Tue, 10 Apr 2001 08:07:04 -0400
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In-Reply-To: <200104091830.NAA03017@ccure.karaya.com> <01040914220214.01893@pc-eng24.mc.com> <20010410075109.A9549@gruyere.muc.suse.de>
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which kind of U/K accaounting are you referring to?

are you referring to global changes in world time? are you referring to time
used by a process? 

I think the reduction of clock interrupts by a factor of 10 would buy us some
performance margin that could be traded for a slightly more complex handler.

On Tue, 10 Apr 2001, Andi Kleen wrote:
> On Mon, Apr 09, 2001 at 02:19:28PM -0400, Mark Salisbury wrote:
> > this is one of linux biggest weaknesses.  the fixed interval timer is a
> > throwback.  it should be replaced with a variable interval timer with interrupts
> > on demand for any system with a cpu sane/modern enough to have an on-chip
> > interrupting decrementer.  (i.e just about any modern chip)
> 
> Just how would you do kernel/user CPU time accounting then ?  It's currently done 
> on every timer tick, and doing it less often would make it useless.
> 
> 
> -Andi
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/*------------------------------------------------**
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**   mbs@mc.com     | System OS - Kernel Team     **
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