Thanks for the reply and I think I have successfully set up codel. Unfortunately I am also new to qdisc. I am trying to compare fq_codel and sfq's performance. I was wondering how to setup a software rate limiting using htb and at the same time have sfq on this bottleneck link using qdisc. Thank you so much! -Mo 2013/11/23 Dave Taht > Why burst 15k? Quantum 1514 works for me. > > While htb will give the best results it is also the most CPU intensive. > > I also note that running it on ingress can be useful especially with ecn. > > IF you have a simple network driver with no ring buffer... Or you have > working BQL... And you want to run at line rate at 100 Mbit... You can > tell your Ethernet driver to switch to 100mbit via > > ethtool -s your device advertise 0x008 > > See also caveats on tso etc: > > > http://www.bufferbloat.net/projects/codel/wiki/Best_Practices_for_Benchmarking_CoDel_and_FQ_CoDel > On Nov 23, 2013 2:26 AM, "Jonathan Morton" wrote: > >> >> On 23 Nov, 2013, at 7:04 am, Dong Mo wrote: >> >> > I am new to codel and I would like to run some experiments with codel >> on a linux box acting as a router. I see on the wiki that running codel on >> linux requires BQL support from NIC driver. I would like to know is this an >> essential requirement to run codel on linux box or it is optional? >> >> It's not a hard requirement - but large hardware queues (which BQL tries >> to solve) tend to interfere with line-rate operation. >> >> > I don't require line rate performance, something like 100Mbps >> throughput will be enough for the experiment. However, It is also not clear >> to me that how Codel is going to interact with some software traffic >> shaping say bandwidth limiting? >> >> tc qdisc add dev $IFACE root handle 1: htb default 1 >> tc class add dev $IFACE parent 1: classid 1:1 htb rate $RATE burst 15k >> tc qdisc add dev $IFACE parent 1:1 handle 10: fq_codel >> >> That works perfectly well if $RATE is less than line rate, even without >> BQL. >> >> - Jonathan Morton >> >> _______________________________________________ >> Codel mailing list >> Codel@lists.bufferbloat.net >> https://lists.bufferbloat.net/listinfo/codel >> >