[Codel] fq_codel_drop vs a udp flood

[Dave Taht]

On Thu, May 5, 2016 at 7:53 AM, Roman Yeryomin <leroi.lists at gmail.com> wrote:
> On 2 May 2016 at 19:14, Eric Dumazet <eric.dumazet at gmail.com> wrote:
>> On Mon, 2016-05-02 at 18:43 +0300, Roman Yeryomin wrote:
>>> On 2 May 2016 at 18:07, Eric Dumazet <eric.dumazet at gmail.com> wrote:
>>> > On Mon, 2016-05-02 at 17:18 +0300, Roman Yeryomin wrote:
>>> >
>>> >> Imagine you are a video operator, have MacBook Pro, gigabit LAN and
>>> >> NAS on ethernet side. You would want to get maximum speed. And
>>> >> fq_codel just dropped it down to 550Mbps for TCP (instead of 750Mbps)
>>> >> and to 30Mbps for UDP (instead of 900Mbps).
>>> >> So, again, it looks broken to me.
>>> >
>>> > Can you show us your qdisc config ?
>>>
>>> Which build do you want? Before it broke or after?
>>>
>>
>>
>> I want to check your qdisc configuration, the one that you used and
>> where you had fq_codel performance issues
>>
>> tc -s -d qdisc
>>
Looks fine.

If you could sample that a few times during your various tests,
that would be good.

> qdisc fq_codel 0: dev eth0 root refcnt 2 limit 1024p flows 1024
> quantum 1514 target 5.0ms interval 100.0ms ecn
>  Sent 12306 bytes 128 pkt (dropped 0, overlimits 0 requeues 0)
>  backlog 0b 0p requeues 0
>   maxpacket 0 drop_overlimit 0 new_flow_count 0 ecn_mark 0
>   new_flows_len 0 old_flows_len 0
> qdisc mq 0: dev wlan0 root
>  Sent 29775 bytes 254 pkt (dropped 0, overlimits 0 requeues 0)
>  backlog 0b 0p requeues 0
> qdisc fq_codel 0: dev wlan0 parent :1 limit 1024p flows 1024 quantum
> 1514 target 5.0ms interval 100.0ms ecn
>  Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
>  backlog 0b 0p requeues 0
>   maxpacket 0 drop_overlimit 0 new_flow_count 0 ecn_mark 0
>   new_flows_len 0 old_flows_len 0
> qdisc fq_codel 0: dev wlan0 parent :2 limit 1024p flows 1024 quantum
> 1514 target 5.0ms interval 100.0ms ecn
>  Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
>  backlog 0b 0p requeues 0
>   maxpacket 0 drop_overlimit 0 new_flow_count 0 ecn_mark 0
>   new_flows_len 0 old_flows_len 0
> qdisc fq_codel 0: dev wlan0 parent :3 limit 1024p flows 1024 quantum
> 1514 target 5.0ms interval 100.0ms ecn
>  Sent 29775 bytes 254 pkt (dropped 0, overlimits 0 requeues 0)
>  backlog 0b 0p requeues 0
>   maxpacket 0 drop_overlimit 0 new_flow_count 0 ecn_mark 0
>   new_flows_len 0 old_flows_len 0
> qdisc fq_codel 0: dev wlan0 parent :4 limit 1024p flows 1024 quantum
> 1514 target 5.0ms interval 100.0ms ecn
>  Sent 0 bytes 0 pkt (dropped 0, overlimits 0 requeues 0)
>  backlog 0b 0p requeues 0
>   maxpacket 0 drop_overlimit 0 new_flow_count 0 ecn_mark 0
>   new_flows_len 0 old_flows_len 0
>
>
> Will try your patch now.
>
> Regards,
> Roman



-- 
Dave Täht
Let's go make home routers and wifi faster! With better software!
http://blog.cerowrt.org