From mboxrd@z Thu Jan  1 00:00:00 1970
From: Shirley Ma <mashirle@us.ibm.com>
Subject: Re: [PATCH] virtio: Avoid virtio_net TX queue over run
Date: Thu, 17 Mar 2011 11:49:18 -0700
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Cc: "Michael S. Tsirkin" <mst@redhat.com>,
	Rusty Russell <rusty@rustcorp.com.au>,
	David Miller <davem@davemloft.net>, kvm@vger.kernel.org,
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To: Eric Dumazet <eric.dumazet@gmail.com>
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On Thu, 2011-03-17 at 10:01 -0700, Shirley Ma wrote:
> On Thu, 2011-03-17 at 17:58 +0100, Eric Dumazet wrote:
> > Could you run your tests with only one cpu ?
> > (offline all cpus but cpu0 on your hypervisor)
> > 
> > Dropping packets is fine, unless consumer cant run ;) 
> 
> Sure, will report the data soon. 

With a single CPU, before/after with this patch the performance has no
difference for both UDP and TCP, and it seems hitting TX overrun, CPU is
100% used.

Thanks
Shirley