Subject: Re: [Netem] Fixed delay patch for netem

From: Stephen Hemminger <[email-masked]>
Date: Mon, 25 Feb 2008 16:54:28 -0800

On Sun, 24 Feb 2008 12:11:16 -0200
"Julio Kriger" <[email-masked]> wrote:

> Hi!
> I have created this patch to add a fixed delay on packet filtered by
> netem. Soon I will send the patch to iproute2.
> This patch comes from a need I have to delay all packets 50ms, beside
> the actual delay setting, like 30ms +- 15 ms. 

Why is 50ms + 30m +/- 15ms any different than 80ms +/- 15ms

> This strike, IMMHO, a
> missing point on gap reordering. If I set "gap 5 delay 10ms" every 5th
> (10th, 15th, ...) packet to go to be sent immediately and every other
> packet to be delayed by 10ms. This  is ok, but I also need a "fixed"
> delay of 50ms to be applied to all packets. Since netem can't be
> nested with himself (so I can do a fixed delay), I needed this new
> feature on netem.

The gap stuff is an awkward interface that should/could have been
done better.

> This patch was create with linux kernel version 2.6.24.2.
> I hope you like it, and it would be great if it goes shiped with the
> next version of the kernel :-))
> Regards,
> Julio Kriger

Maybe, but it is getting confusing with all the growth of parameters.
Probably time for a rethink.