From mboxrd@z Thu Jan  1 00:00:00 1970
From: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Subject: Re: [PATCH 6/6] examples/vhost: add an option to enable
 Tx zero copy
Date: Tue, 23 Aug 2016 20:33:21 +0800
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Cc: dev@dpdk.org, Maxime Coquelin <maxime.coquelin@redhat.com>
To: Thomas Monjalon <thomas.monjalon@6wind.com>
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On Tue, Aug 23, 2016 at 11:31:08AM +0200, Thomas Monjalon wrote:
> 2016-08-23 16:10, Yuanhan Liu:
> > One thing worth noting while using Tx zero copy is the nb_tx_desc has
> > to be small enough so that the eth driver will hit the mbuf free
> > threshold easily and thus free mbuf more frequently.
> > 
> > The reason behind that is, when Tx zero copy is enabled, guest Tx used
> > vring will be updated only when corresponding mbuf is freed. If mbuf is
> > not freed frequently, the guest Tx vring could be starved.
> 
> I think you should explain this behaviour in the doc of the vhost flag.

Agreed. Will do it in v2.

	--yliu