[Make-wifi-fast] [Codel] fq_codel_drop vs a udp flood
eric.dumazet at gmail.com
Thu May 5 15:23:27 EDT 2016
On Thu, 2016-05-05 at 19:25 +0300, Roman Yeryomin wrote:
> On 5 May 2016 at 19:12, Eric Dumazet <eric.dumazet at gmail.com> wrote:
> > On Thu, 2016-05-05 at 17:53 +0300, Roman Yeryomin wrote:
> >> 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
> > Limit of 1024 packets and 1024 flows is not wise I think.
> > (If all buckets are in use, each bucket has a virtual queue of 1 packet,
> > which is almost the same than having no queue at all)
> > I suggest to have at least 8 packets per bucket, to let Codel have a
> > chance to trigger.
> > So you could either reduce number of buckets to 128 (if memory is
> > tight), or increase limit to 8192.
> Will try, but what I've posted is default, I didn't change/configure that.
fq_codel has a default of 10240 packets and 1024 buckets.
If someone changed that in the linux variant you use, he probably should
explain the rationale.
More information about the Make-wifi-fast