[Codel] [RFC PATCH] Codel: Enable packet drop with ECN-marked packets on a threshold

[Eric Dumazet]

On Sun, 2012-06-17 at 22:40 -0400, Dave Taht wrote:

> (side note, I noticed fq_codel defaulted to 10k packets which is
> rather excessive for tiny routers - I just trimmed that down
> significantly for cerowrt and the upcoming 3.3.8-4 release has the rfc
> patch in it)
> 
> And apologies for not seeing this long ago,

10k packets is too small to absorb a burst of 64bytes packets on 10Gb
links. Whole CoDel point is to accept packets at enqueue and drop them
at dequeue _if_ sejourn time too big. Number of packets should be
irrelevant.

If you don't know how much packet can be sent on wire per unit of time,
just set a reasonable big limit.

1000 packets limit is not reasonable, while 10k is.

linux average machines have more ram than tiny routers, dont assume we
release specialized code. It should be generic enough, granted it can be
easily tuned.