netdev - Re: amplifying qdisc

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Date:   Wed, 8 Jul 2020 23:26:34 -0700
From:   Stephen Hemminger <stephen@...workplumber.org>
To:     Russell Strong <russell@...ong.id.au>
Cc:     netdev@...r.kernel.org
Subject: Re: amplifying qdisc

On Thu, 9 Jul 2020 16:10:34 +1000
Russell Strong <russell@...ong.id.au> wrote:

> Hi,
> 
> I'm attempting to fill a link with background traffic that is sent
> whenever the link is idle.  To do this I've creates a qdisc that will
> repeat the last packet in the queue for a defined number of times
> (possibly infinite in the future). I am able to control the contents of
> the fill traffic by sending the occasional packet through this qdisc.
> 
> This is works as the root qdisc and below a TBF.  When I try it as a
> leaf of HTB unexpected behaviour ensues.  I suspect my approach is
> violating some rules for qdiscs?  Any help/ideas/pointers would be
> appreciated.

Netem can already do things like this. Why not add to that