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Subject: Re: hackbench regression due to commit 9dfc6e68bfe6e
From: Eric Dumazet <eric.dumazet@gmail.com>
To: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
Cc: Christoph Lameter <cl@linux-foundation.org>,
       Pekka Enberg <penberg@cs.helsinki.fi>, netdev <netdev@vger.kernel.org>,
       Tejun Heo <tj@kernel.org>, alex.shi@intel.com,
       "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
       "Ma, Ling" <ling.ma@intel.com>, "Chen, Tim C" <tim.c.chen@intel.com>,
       Andrew Morton <akpm@linux-foundation.org>
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Date: Thu, 08 Apr 2010 09:54:32 +0200
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Le jeudi 08 avril 2010 à 15:54 +0800, Zhang, Yanmin a écrit :

> If there are 2 nodes in the machine, processes on node 0 will contact MCH of
> node 1 to access memory of node 1. I suspect the MCH of node 1 might enter
> a power-saving mode when all the cpus of node 1 are free. So the transactions
> from MCH 1 to MCH 0 has a larger latency.
> 

Hmm, thanks for the hint, I will investigate this.


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