Re: Traffic shaping at 10~300mbps at a 10Gbps link

[Jesper Dangaard Brouer <brouer@redhat.com>]

(Reply inlined below, please learn howto reply inline)

On Thu, 17 Jun 2021 12:20:32 -0300
"Ethy H. Brito" <ethy.brito@inexo.com.br> wrote:

> Hi. mr. Brouer
> 
> I read your comment at lists.bufferbloat.net about my issue shaping traffic.

 https://lists.bufferbloat.net/pipermail/bloat/2021-June/016441.html
 
> I don't know how it ended up there since I opened it at LARTC, I am
> not a subscriber to bufferbloat list.

Yes, Rich (cc) moved your email to the bufferbloat list.  I just
pointed out that your reported issue was a classical TC root-queue
locking issue (as someone else mis-interpreted this).

I'm Cc'ing XDP-newbies list, as we should share our finding with the
community on how this TC-lock problem can be solve with XDP.


> About your XDP-project solution, how can I test it? 

There a two solutions in XDP-project involving TC-BPF in combination
with XDP.  The one you are talking about is:

 [2] https://github.com/xdp-project/xdp-cpumap-tc


> I read the "tc_mq_htb_setup_example.sh" script and did not understand
> it completely.

 [3] https://github.com/xdp-project/xdp-cpumap-tc/blob/master/bin/tc_mq_htb_setup_example.sh

> Do you think it will sove my problem?

Well, yes, *but* notice there are some "home-work" in the bottom of the
script.  You need to code-up the redirecting to the appropriate CPUs
yourself... it will be specific to your use-case if you can partition
the traffic to avoid the TC root-lock.

Can you explain you use-case for us?

> Would you help with my doubts so I can implementing it?

Let help each-other. It doesn't scale that I help on an individual
level.  That is why I bring this to the mailing list
(xdp-newbies@vger.kernel.org).  Also Cc'ing Yoel and Robert, that have
related interests in this.

I do acknowledge that the documentation in [2] is lacking. Perhaps a
goal should be that we add documentation on howto use it?

A longer term goal is to add contents to this almost empty repo:
 https://github.com/xdp-project/BNG-router

-- 
Best regards,
  Jesper Dangaard Brouer
  MSc.CS, Principal Kernel Engineer at Red Hat
  LinkedIn: http://www.linkedin.com/in/brouer