Re: [PATCH net-next v2 0/9] xsk: improvement performance in copy mode

[Jakub Kicinski <kuba@kernel.org>]

On Tue, 26 Aug 2025 08:51:24 +0800 Jason Xing wrote:
> > > Sorry for missing the question. I'm not very familiar with how to run the
> > > test based on AF_PACKET. Could you point it out for me? Thanks.
> > >
> > > I remember the very initial version of AF_XDP was pure AF_PACKET. So
> > > may I ask why we expect to see the comparison between them?  
> >
> > Pretty sure I told you this at least twice but the point of AF_XDP
> > is the ZC mode. Without a comparison to AF_PACKET which has similar
> > functionality optimizing AF_XDP copy mode seems unjustified.  
> 
> Oh, I see. Let me confirm again that you expect to see a demo like the
> copy mode of AF_PACKET v4 [1] and see the differences in performance,
> right?
> 
> If AF_PACKET eventually outperforms AF_XDP, do we need to reinvent the
> copy mode based on AF_PACKET?
> 
> And if a quick/simple implementation is based on AF_PACKET, it
> shouldn't be that easy to use the same benchmark to see which one is
> better. That means inventing a new unified benchmark tool is
> necessary?

To be honest I suspect you can get an LLM to convert your AF_XDP test
to use AF_PACKET..