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From: Michael Neuling <mikey@neuling.org>
To: Peter Zijlstra <peterz@infradead.org>
Subject: Re: [PATCH 2/2] powerpc: implement arch_scale_smt_power for Power7
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Date: Thu, 21 Jan 2010 10:58:01 +1300
Message-ID: <29111.1264024681@neuling.org>
Cc: ego@in.ibm.com, Andreas Herrmann <andreas.herrmann3@amd.com>,
	linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
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> > On Power7 processors running in SMT4 mode with 2, 3, or 4 idle threads 
> > there is performance benefit to idling the higher numbered threads in
> > the core.  
> 
> So this is an actual performance improvement, not only power savings?

It's primarily a performance improvement.  Any power/energy savings
would be a bonus.  

Mikey