Message-ID: <44D771A7.7040605@zytor.com>
Date: Mon, 07 Aug 2006 10:00:23 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: "Eric W. Biederman" <ebiederm@xmission.com>
CC: "Randy.Dunlap" <rdunlap@xenotime.net>, Andrew Morton <akpm@osdl.org>,
       Andi Kleen <ak@suse.de>,
       "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86_64: Make NR_IRQS configurable in Kconfig
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Eric W. Biederman wrote:
> 
> a) Because I would like to flush out bugs.
> b) Because I want a default that works for everyone.
> c) Because with MSI we have a potential for large irq counts on most systems.
> d) Because anyone who disagrees with me can send a patch and fix
>    the default.
> e) Because with the default number of cpus we can very close to needing
>    this many irqs in the worst case.
> f) This is much better than previous to my patch and setting NR_CPUS=255
>    and getting 8K IRQS.
> g) Because I probably should have been more inventive than copying the
>    NR_IRQS text, but when I did the wording sounded ok to me.
> 

Why not simply reserve 224*NR_CPUS IRQs? If you have 256 CPUs allocating 
64K IRQs should hardly matter :)

	-hpa
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