From: Dave Jones <davej@redhat.com>
To: Pieter De Wit <pieter@insync.za.net>
Cc: cpufreq@vger.kernel.org
Subject: Re: Detection of HyperThreading
Date: Mon, 2 May 2011 12:15:57 -0400 [thread overview]
Message-ID: <20110502161557.GA25722@redhat.com> (raw)
In-Reply-To: <alpine.DEB.2.02.1105021542530.2853@eragon.insync.za.net>
On Mon, May 02, 2011 at 03:47:30PM +1200, Pieter De Wit wrote:
> Hello Guys,
>
> I found something quite weird over the weekend. I have a few machines that
> claim they have HT (using cat /proc/cpuinfo). These machines doesn't
> really support HT (both with the number of threads and Intel's website)
>
> I was wondering:
>
> a) Is this the right list to send to (Sorry if not)
no, this list is for cpu frequency scaling. linux-kernel would have been
more appropriate.
> and
>
> b) How is the HT flag detected ?
>
> CPU's like the Core2 Duo E6300 doesn't have HT, but yet the flag is
> displayed ? See http://ark.intel.com/Product.aspx?id=27248 for info. I can
> send a dump of /proc/cpuinfo later from home.
the 'ht' flag in /proc/cpuinfo means "this cpu knows how to report how
many siblings it has". On a CPU which doesn't have hyperthreading, that
number will be 0.
Dave
prev parent reply other threads:[~2011-05-02 16:15 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-02 3:47 Detection of HyperThreading Pieter De Wit
2011-05-02 16:15 ` Dave Jones [this message]
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