From: Andi Kleen <ak@suse.de>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Subject: Re: [PATCH] x86_64: Make NR_IRQS configurable in Kconfig
Date: Mon, 7 Aug 2006 17:33:13 +0200
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       "Protasevich, Natalie" <Natalie.Protasevich@unisys.com>,
       linux-kernel@vger.kernel.org
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On Monday 07 August 2006 17:26, Eric W. Biederman wrote:
> 
> Currrently on a SMP system we can theoretically support
> NR_CPUS*224 irqs.  Unfortunately our data structures
> don't cope will with that many irqs, nor does hardware
> typically provide that many irq sources.
> 
> With the number of cores starting to follow Moores
> law, and the apicid limits being raised beyond an 8bit
> number trying to track our current maximum with our
> current data structures would be fatal and wasteful.
> 
> So this patch decouples the number of irqs we support
> from the number of cpus.  We can revisit this decision
> once someone reworks the current data structures.

Ok. I was about to apply it, but it seems to require
mm patches right now, so i didn't

-Andi
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