[dpdk-dev] [PATCH v2] add mtu set in virtio

[Dey, Souvik]

Hi Maxime,
	When is patches or new implementation going to come in the release ? if it is not 16.11 then, can we keep this change till the new virtio changes come in the release. And if it is already planned for 16.11, then can I get a little more information on that.

--
Regards,
Souvik

-----Original Message-----
From: Maxime Coquelin [mailto:maxime.coquelin at redhat.com] 
Sent: Tuesday, August 30, 2016 3:58 AM
To: Dey, Souvik <sodey at sonusnet.com>; stephen at networkplumber.org; huawei.xie at intel.com; yuanhan.liu at linux.intel.com
Cc: dev at dpdk.org
Subject: Re: [dpdk-dev] [PATCH v2] add mtu set in virtio

Hi Souvik,

On 08/30/2016 01:02 AM, souvikdey33 wrote:
> Signed-off-by: Souvik Dey <sodey at sonusnet.com>
>
> Fixes: 1fb8e8896ca8 ("Signed-off-by: Souvik Dey <sodey at sonusnet.com>")
> Reviewed-by: Stephen Hemminger <stephen at 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.

Regards,
Maxime