Re: [dpdk-dev] [RFC] lib/librte_vhost: qemu vhost-user support into DPDK vhost library

["Ouyang, Changchun" <changchun.ouyang@intel.com>]

Hi Tetsuya

Thanks for your response.
Agree with you, the performance should be same as the data path (RX/TX) is not affected,
The difference between implementation only exists in the virtio device creation and destroy stage.

Regards,
Changchun

> -----Original Message-----
> From: Tetsuya.Mukawa [mailto:mukawa@igel.co.jp]
> Sent: Wednesday, August 27, 2014 12:39 PM
> To: Ouyang, Changchun; dev@dpdk.org
> Cc: Xie, Huawei; Katsuya MATSUBARA; nakajima.yoshihiro@lab.ntt.co.jp;
> Hitoshi Masutani
> Subject: Re: [dpdk-dev] [RFC] lib/librte_vhost: qemu vhost-user support into
> DPDK vhost library
> 
> 
> (2014/08/27 9:43), Ouyang, Changchun wrote:
> > Do we have performance comparison between both implementation?
> Hi Changchun,
> 
> If DPDK applications are running on both guest and host side, the
> performance should be almost same, because while transmitting data virt
> queues are accessed by virtio-net PMD and libvhost. In libvhost, the existing
> vhost implementation and a vhost-user implementation will shares or uses
> same code to access virt queues. So I guess the performance will be almost
> same.
> 
> Thanks,
> Tetsuya
> 
> 
> > Thanks
> > Changchun
> >
> >
> > -----Original Message-----
> > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Xie, Huawei
> > Sent: Tuesday, August 26, 2014 7:06 PM
> > To: dev@dpdk.org
> > Subject: Re: [dpdk-dev] [RFC] lib/librte_vhost: qemu vhost-user
> > support into DPDK vhost library
> >
> > Hi all:
> > We are implementing qemu official vhost-user interface into DPDK vhost
> library, so there would be two coexisting implementations for user space
> vhost backend.
> > Pro and cons in my mind:
> > Existing solution:
> > Pros:  works with qemu version before 2.1;  Cons: depends on eventfd
> proxy kernel module and extra maintenance effort Qemu vhost-user:
> >                Pros:  qemu official us-vhost interface;     Cons: only available after
> qemu 2.1
> >
> > BR.
> > huawei