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To: Tong Li <tong.n.li@intel.com>
Cc: mingo@elte.hu, linux-kernel@vger.kernel.org
Subject: Re: [RFC] scheduler: improve SMP fairness in CFS
References: <Pine.LNX.4.64.0707231123080.3239@tongli.jf.intel.com>
From: Andi Kleen <andi@firstfloor.org>
Date: 23 Jul 2007 22:00:02 +0200
In-Reply-To: <Pine.LNX.4.64.0707231123080.3239@tongli.jf.intel.com>
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Tong Li <tong.n.li@intel.com> writes:
> +
> +        read_lock_irqsave(&dwrr_highest_lock, flags);

That lock looks like it would bounce between CPUs like crazy.
Did you try any benchmarks on a larger system? 

-Andi