Re: [PATCH iproute2] codel: add ce_threshold support to codel & fc_codel

[Stephen Hemminger <stephen@networkplumber.org>]

On Mon, 11 May 2015 10:44:55 -0700
Eric Dumazet <eric.dumazet@gmail.com> wrote:

> From: Eric Dumazet <edumazet@google.com>
> 
> codel & fq_codel packet schedulers are now able to have a threshold
> for CE marking packets, regardless of the drop/nodrop decision taken by
> CoDel.
> 
> This is particularly useful for dctcp and variants, that do not use
> traditional ECN.
> 
> Note that fq_codel users would have to specify noecn if ce_threshold is
> used, otherwise results would be not very interesting, as ecn is default
> on for fq_codel.
> 
> $ tc -s qdisc show dev eth1
> qdisc codel 8002: root refcnt 45 limit 1000p target 5.0ms ce_threshold
> 1.0ms interval 100.0ms 
>  Sent 4908469888317 bytes 3351813967 pkt (dropped 0, overlimits 0
> requeues 21624365) 
>  rate 37671Mbit 3231836pps backlog 4904740b 250p requeues 21624365 
>   count 0 lastcount 0 ldelay 1.1ms drop_next 0us
>   maxpacket 68130 ecn_mark 0 drop_overlimit 0 ce_mark 410861803
> 
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Applied to net-next branch