Re: [RFC 0/2] introduce LLC aware functions

[Stephen Hemminger <stephen@networkplumber.org>]

On Wed, 4 Sep 2024 11:30:59 +0200
Mattias Rönnblom <hofors@lysator.liu.se> wrote:

> On 2024-09-02 02:39, Varghese, Vipin wrote:
> > <snipped>
> > 
> > Thank you Mattias for the comments and question, please let me try to 
> > explain the same below
> >   
> >> We shouldn't have a separate CPU/cache hierarchy API instead?  
> > 
> > Based on the intention to bring in CPU lcores which share same L3 (for 
> > better cache hits and less noisy neighbor) current API focuses on using
> > 
> > Last Level Cache. But if the suggestion is `there are SoC where L2 cache 
> > are also shared, and the new API should be provisioned`, I am also
> > 
> > comfortable with the thought.
> >   
> 
> Rather than some AMD special case API hacked into <rte_lcore.h>, I think 
> we are better off with no DPDK API at all for this kind of functionality.
> 
> A DPDK CPU/memory hierarchy topology API very much makes sense, but it 
> should be reasonably generic and complete from the start.

Agreed. This one of those cases where the existing project hwloc which
is part of open-mpi is more complete and well supported. It supports
multiple OS's and can deal with more quirks.

https://github.com/open-mpi/hwloc