From mboxrd@z Thu Jan  1 00:00:00 1970
From: Todd And Margo Chester <toddandmargo@gmail.com>
Subject: What are the rules for hyperthreaded CPUs?
Date: Sun, 04 Dec 2011 17:26:31 -0800
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> Hi All,
>
> My host has an i7-960 processor (4 cores, 8 hypterthreaded cores.)
> /proc/cpuinfo on my host shows 8 processors.
>
> On my Fedora Core 16 guest, /proc/cpuinfo shows 4 processors.
>
> Question: what is the maximum number of processors I can assign to my
> guest?  4 or 8?  What are the rules for Hyperthreading?
>
> Many thanks,
> -T

Figured it out.  The max cores is the number of hyperthreaded cores
(eight in my case).

My mistake was that in virt-manager, processor, I was not clicking
on "Copy host CPU configuration" button.  Without that, everything
I tried to configure came out as single CPUs.

-T