Re: Virtio_net support vxlan encapsulation package TSO offload discuss

[Jason Wang <jasowang@redhat.com>]

On 2016年11月08日 19:13, Jason Wang wrote:
> Cc Michael
>
> On 2016年11月08日 16:34, Zhangming (James, Euler) wrote:
>>
>> In container scenario, OVS is installed in the Virtual machine, and 
>> all the containers connected to the OVS will communicated through 
>> VXLAN encapsulation.
>>
>> By now, virtio_net does not support TSO offload for VXLAN 
>> encapsulated TSO package. In this condition, the performance is not 
>> good, sender is bottleneck
>>
>> I googled this scenario, but I didn’t find any information. Will 
>> virtio_net support VXLAN encapsulation package TSO offload later?
>>
>
> Yes and for both sender and receiver.
>
>> My idea is virtio_net open encapsulated TSO offload, and transport 
>> encapsulation info to TUN, TUN will parse the info and build skb with 
>> encapsulation info.
>>
>> OVS or kernel on the host should be modified to support this. Using 
>> this method, the TCP performance aremore than 2x as before.
>>
>> Any advice and suggestions for this idea or new idea will be greatly 
>> appreciated!
>>
>> Best regards,
>>
>>    James zhang
>>
>
> Sounds very good. And we may also need features bits 
> (VIRTIO_NET_F_GUEST|HOST_GSO_X) for this.
>
> This is in fact one of items in networking todo list. (See 
> http://www.linux-kvm.org/page/NetworkingTodo). While at it, we'd 
> better support not only VXLAN but also other tunnels.

Cc Vlad who is working on extending virtio-net headers.

>
> We can start with the spec work, or if you've already had some bits 
> you can post them as RFC for early review.
>
> Thanks