From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Yuyang Du" <duyuyang@gmail.com>
Subject: Re: Re: PV kernel boot parameter maxcpus has noeffect?
Date: Wed, 28 Apr 2010 18:18:01 +0800
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>However, given that the bringing up of secondary CPUs happens from common (even arch-independent) code, the whole issue
>seems a little suspicious - namely what indication he uses to see that there are more than 4 vCPU-s in use by Dom0.

I was not clear, and using maxcpus boot parameter in dom0 kernel is not what I want. 

I wanted to let xen see only one socket and schedule only that socket (4 cores), so giving dom0 kernel boot parameter does not help. So I was wrong about that.

What I am looking for is to tell xen to schedule only a portion of the available physical processors to whatever VMs, is there any method? I checked the BIOS options, and there is no way to disable a processor.

Thanks,
Shawn