From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: hackbench regression due to commit 9dfc6e68bfe6e
Date: Thu, 08 Apr 2010 09:54:32 +0200
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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>
To: "Zhang, Yanmin" <yanmin_zhang@linux.intel.com>
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Le jeudi 08 avril 2010 =C3=A0 15:54 +0800, Zhang, Yanmin a =C3=A9crit :

> 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 tran=
sactions
> from MCH 1 to MCH 0 has a larger latency.
>=20

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