public inbox for netdev@vger.kernel.org 
 help / color / mirror / Atom feed
From: "Paweł Staszewski" <pstaszewski@itcare•pl>
To: "John A. Sullivan III" <jsullivan@opensourcedevel•com>
Cc: Eric Dumazet <eric.dumazet@gmail•com>, netdev@vger•kernel.org
Subject: Re: IFB and bridges
Date: Wed, 14 Dec 2011 20:36:34 +0100	[thread overview]
Message-ID: <4EE8FAC2.4090303@itcare.pl> (raw)
In-Reply-To: <9ab07532-3d46-4e4a-8baf-5863b0cec5db@jasiiieee>

W dniu 2011-12-12 01:42, John A. Sullivan III pisze:
>
> ----- Original Message -----
>> From: "Eric Dumazet"<eric.dumazet@gmail•com>
>> To: "John A. Sullivan III"<jsullivan@opensourcedevel•com>
>> Cc: netdev@vger•kernel.org
>> Sent: Sunday, December 11, 2011 5:00:59 PM
>> Subject: Re: IFB and bridges
>>
>> Le dimanche 11 décembre 2011 à 17:38 -0500, John A. Sullivan III a>
>>> I know IFB is often used for ingress but I wasn't really thinking
>>> of
>>> ingress filtering.  Let's say I have a 12 port Linux switch.  If
>>> any
>>> of the ports become backlogged, I want them to prioritize time
>>> sensitive traffic so I implement traffic shaping but I don't want
>>> to
>>> have to define my qdiscs, classes, and filters 12 times over if
>>> they
>>> are all the same.  So I would direct each port to an IFB (not sure
>>> if
>>> that's intolerable overhead), have a single set of qdiscs, classes,
>>> and filters, and, once those are applied, the packet arrives back
>>> on
>>> the same interface and proceeds assuming if has not been dropped or
>>> delayed. - John
>> Really ? How are you going to shape a single IFB device, if you
>> really
>> have independant 12 ports. (Its a switch, not a hub after all)
>>
>> A script can define your qdiscs/classes/filters hundred times, or one
>> thousand times, and writing such a script is far more easier than
>> setup
>> IFB.
>>
>>
>>
>>
> <grin>  That's why I thought I'd ask the experts :) - John
> --
> To unsubscribe from this list: send the line "unsubscribe netdev" in
> the body of a message to majordomo@vger•kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>
>
Also directing all traffic from all 12 ports is not good idea :)
It is performance killer

IFB can't handle too much pps

Also - You can't have too many tc filters/classes on one single IFB 
device because this is also performance killer.

      reply	other threads:[~2011-12-14 19:36 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-12-11  1:15 IFB and bridges John A. Sullivan III
2011-12-11  8:58 ` Eric Dumazet
2011-12-11 22:38   ` John A. Sullivan III
2011-12-11 22:00     ` Eric Dumazet
2011-12-12  0:42       ` John A. Sullivan III
2011-12-14 19:36         ` Paweł Staszewski [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4EE8FAC2.4090303@itcare.pl \
    --to=pstaszewski@itcare$(echo .)pl \
    --cc=eric.dumazet@gmail$(echo .)com \
    --cc=jsullivan@opensourcedevel$(echo .)com \
    --cc=netdev@vger$(echo .)kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox