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Message-ID: <86802c440812141939s2fe0fd9g5f9899ed9e4f6e6c@mail.gmail.com>
Date: Sun, 14 Dec 2008 19:39:48 -0800
From: "Yinghai Lu" <yinghai@kernel.org>
To: "Andi Kleen" <andi@firstfloor.org>
Subject: Re: [PATCH] add command line init_start_cpus
Cc: "Andrew Morton" <akpm@linux-foundation.org>, "Ingo Molnar" <mingo@elte.hu>,
       "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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On Sun, Dec 14, 2008 at 4:11 PM, Andi Kleen <andi@firstfloor.org> wrote:
> Yinghai Lu <yinghai@kernel.org> writes:
>
>> Impact: new command line
>>
>> so could select cpus to be started during init stage
>
> maxcpus=N should do this already, at least for the first N cpus.
> If you really need a non continuous range of N (why?) then it would
> be better to fix maxcpus instead of adding a new option.

it seems it is hard to make maxcpus= to support random cpus selecting and
maxcpus=0 looks insane

also maxcpus=1, will disable smp, can you enable other cpus later in user space?

YH