From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: [RFC PATCH] net: add additional lock to qdisc to increase enqueue/dequeue fairness
Date: Wed, 24 Mar 2010 03:12:12 +0100
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References: <20100323202553.21598.10754.stgit@gitlad.jf.intel.com>
	<20100323.133124.139557595.davem@davemloft.net>
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Cc: alexander.h.duyck@intel.com, netdev@vger.kernel.org
To: David Miller <davem@davemloft.net>
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In-Reply-To: <20100323.133124.139557595.davem@davemloft.net> (David Miller's message of "Tue, 23 Mar 2010 13:31:24 -0700 (PDT)")
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David Miller <davem@davemloft.net> writes:

> From: Alexander Duyck <alexander.h.duyck@intel.com>
> Date: Tue, 23 Mar 2010 13:25:53 -0700
>
>> The qdisc layer shows a significant issue when you start transmitting from
>> multiple CPUs.
>
> Why are you hitting any central qdisc lock on a multiqueue
> configuration?

One thing to remember is that systems can have a lot more CPUs than a NIC queues
(e.g. 64 vs 8)

-Andi

-- 
ak@linux.intel.com -- Speaking for myself only.