Re: [dpdk-dev] KNI alternatives

[Thomas Monjalon <thomas@monjalon.net>]

13/01/2021 19:17, Igor Ryzhov:
> On Wed, Jan 13, 2021 at 8:10 PM Stephen Hemminger <
> stephen@networkplumber.org> wrote:
> > On Wed, Jan 13, 2021, 9:06 AM Thomas Monjalon <thomas@monjalon.net> wrote:
> >
> > > Hi,
> > >
> > > As discussed today in the techboard meeting, KNI has probably
> > > better alternatives today without using an out-of-tree module.
> > > Virtio-user is a good candidate to replace KNI.
> > > What is the performance of TAP?
> > > Is there a way to leverage af_packet, af_xdp, or even pcap interfaces?
> > 
> > Last time I tried.
> > Virtio user was as fast as KNI and consumed less cpu. Was seeing 10mpps
> > Tap was much slower. Like 1mpps.
> 
> Performance is not the only question. The advantage of KNI we are currently
> using is
> the ability to control the DPDK interfaces by the kernel.
> For example, to implement bonding in the DPDK application, it is possible
> to create KNI
> pair for each physical interface, create a bond interface in Linux over
> those KNI interfaces
> and just pass LACP packets between the app and the kernel. The kernel
> itself will control
> MACs, MTU, etc. of underlying interfaces. AFAIK it's not possible with
> virtio-user or tap.
> Am I wrong?

I see at least 2 alternatives for bonding with kernel management:
	- mlx5 bonding
	- af_xdp interface for most of NICs