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Date: Wed, 7 Sep 2016 11:25:47 +0800
From: Yuanhan Liu <yuanhan.liu@linux.intel.com>
To: Maxime Coquelin <maxime.coquelin@redhat.com>
Cc: souvikdey33 <sodey@sonusnet.com>, stephen@networkplumber.org,
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Subject: Re: [dpdk-dev] [PATCH v2] add mtu set in virtio
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On Tue, Aug 30, 2016 at 09:57:39AM +0200, Maxime Coquelin wrote:
> Hi Souvik,
> 
> On 08/30/2016 01:02 AM, souvikdey33 wrote:
> >Signed-off-by: Souvik Dey <sodey@sonusnet.com>
> >
> >Fixes: 1fb8e8896ca8 ("Signed-off-by: Souvik Dey <sodey@sonusnet.com>")
> >Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
> >
> >Virtio interfaces should also support setting of mtu, as in case of cloud
> >it is expected to have the consistent mtu across the infrastructure that
> >the dhcp server sends and not hardcoded to 1500(default).
> >---
> > drivers/net/virtio/virtio_ethdev.c | 12 ++++++++++++
> > 1 file changed, 12 insertions(+)
> 
> FYI, there are some on-going changes in the VIRTIO specification
> so that the VHOST interface exposes its MTU to its VIRTIO peer.
> It may also be used as an alternative of what you patch achieves.
> 
> I am working on its implementation in Qemu/DPDK, our goal being to
> reduce performance drops for small packets with Rx mergeable buffers
> feature enabled.

Mind to educate me a bit on how that works?

	--yliu