fq_codel not working on saturated link?












2














I'm setting up a test to saturate a link between two machines with a gig router in between them, then run fq_codel on Debian Buster and see if my ping times can improve (what I think fq_codel is supposed to do if it's working).



On machine A I force my NIC to 10Mbps like



ethtool -s enp8s0 advertise 0x002


Then my gigabit router shows the link speed of this box as 10Mbps. Then I try to ping machine B and get times of around 0.5ms, then to saturate the link I do



dd if=/dev/urandom | ssh user@192.168.10.150 dd of=/dev/null


Then I get pings of around 10ms. Then I try to enable fq_codel like:



tc qdisc add dev enp8s0 root fq_codel


But my pings stay at around 10ms. So I try to see what enp8s0 is doing, here's what I get:



tc qdisc show dev enp8s0
qdisc fq_codel 8001: root refcnt 6 limit 10240p flows 1024
quantum 1514 target 5.0ms interval 100.0ms memory_limit 32Mb ecn


What am I doing wrong, or how can I test better, or understand what's happening?










share|improve this question



























    2














    I'm setting up a test to saturate a link between two machines with a gig router in between them, then run fq_codel on Debian Buster and see if my ping times can improve (what I think fq_codel is supposed to do if it's working).



    On machine A I force my NIC to 10Mbps like



    ethtool -s enp8s0 advertise 0x002


    Then my gigabit router shows the link speed of this box as 10Mbps. Then I try to ping machine B and get times of around 0.5ms, then to saturate the link I do



    dd if=/dev/urandom | ssh user@192.168.10.150 dd of=/dev/null


    Then I get pings of around 10ms. Then I try to enable fq_codel like:



    tc qdisc add dev enp8s0 root fq_codel


    But my pings stay at around 10ms. So I try to see what enp8s0 is doing, here's what I get:



    tc qdisc show dev enp8s0
    qdisc fq_codel 8001: root refcnt 6 limit 10240p flows 1024
    quantum 1514 target 5.0ms interval 100.0ms memory_limit 32Mb ecn


    What am I doing wrong, or how can I test better, or understand what's happening?










    share|improve this question

























      2












      2








      2







      I'm setting up a test to saturate a link between two machines with a gig router in between them, then run fq_codel on Debian Buster and see if my ping times can improve (what I think fq_codel is supposed to do if it's working).



      On machine A I force my NIC to 10Mbps like



      ethtool -s enp8s0 advertise 0x002


      Then my gigabit router shows the link speed of this box as 10Mbps. Then I try to ping machine B and get times of around 0.5ms, then to saturate the link I do



      dd if=/dev/urandom | ssh user@192.168.10.150 dd of=/dev/null


      Then I get pings of around 10ms. Then I try to enable fq_codel like:



      tc qdisc add dev enp8s0 root fq_codel


      But my pings stay at around 10ms. So I try to see what enp8s0 is doing, here's what I get:



      tc qdisc show dev enp8s0
      qdisc fq_codel 8001: root refcnt 6 limit 10240p flows 1024
      quantum 1514 target 5.0ms interval 100.0ms memory_limit 32Mb ecn


      What am I doing wrong, or how can I test better, or understand what's happening?










      share|improve this question













      I'm setting up a test to saturate a link between two machines with a gig router in between them, then run fq_codel on Debian Buster and see if my ping times can improve (what I think fq_codel is supposed to do if it's working).



      On machine A I force my NIC to 10Mbps like



      ethtool -s enp8s0 advertise 0x002


      Then my gigabit router shows the link speed of this box as 10Mbps. Then I try to ping machine B and get times of around 0.5ms, then to saturate the link I do



      dd if=/dev/urandom | ssh user@192.168.10.150 dd of=/dev/null


      Then I get pings of around 10ms. Then I try to enable fq_codel like:



      tc qdisc add dev enp8s0 root fq_codel


      But my pings stay at around 10ms. So I try to see what enp8s0 is doing, here's what I get:



      tc qdisc show dev enp8s0
      qdisc fq_codel 8001: root refcnt 6 limit 10240p flows 1024
      quantum 1514 target 5.0ms interval 100.0ms memory_limit 32Mb ecn


      What am I doing wrong, or how can I test better, or understand what's happening?







      debian buffer






      share|improve this question













      share|improve this question











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      asked Dec 24 '18 at 22:22









      batflaps

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