Re: [libvirt-users] Strange QoS behavior

2012/12/4 Davide Guerri <davide.guerri(a)gmail.com <mailto:davide.guerri@gmail.com>> Here they are: !(~) # tc class show dev vnet43 class htb 1:1 root prio 0 rate 20480Kbit ceil 20480Kbit burst 1597b cburst 1597b !(~) # tc filter show dev vnet43 filter parent 1: protocol ip pref 49152 fw filter parent 1: protocol ip pref 49152 fw handle 0x1 classid :1 !(~) # tc qdisc show dev vnet43 qdisc htb 1: root refcnt 2 r2q 10 default 1 direct_packets_stat 0 qdisc ingress ffff: parent ffff:fff1 ---------------- On 03/dic/2012, at 17:19, Michal Privoznik <mprivozn(a)redhat.com <mailto:mprivozn@redhat.com>> wrote: > On 03.12.2012 16:37, Davide Guerri wrote: >> Hi, >> I'm having some weird problem with the setup of the QoS on a bridged network. >> >> As the docs states, outbound/inbound average speed should be expressed in KBps (KBytes per second) but in order to get a maximum speed of 10Mbps (megabits per second) surprising enough I have to use 2560 on the guest (not 1280 as expected). >> Using 1280 units I get a speed og 5Mbps. >> >> I'm aware of peak and burst parameters but even with them I'm seeing the same (long-term) behavior. >> >> Here follows my configuration. >> >> Thank you in advance for any help you can provide. >> >> >> >> Domain definition (relevant part only) >> >> virsh # dumpxml mydomain >> <domain type='kvm' id='45'> >> [...] >> <devices> >> [...] >> <interface type='network'> >> <mac address='52:54:00:xx:xx:xx'/> >> <source network='br909'/> >> <target dev='vnet43'/> >> <model type='virtio'/> >> <bandwidth> >> <inbound average='2560'/> >> <outbound average='2560'/> >> </bandwidth> >> <alias name='net0'/> >> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> >> </interface> >> [...] >> </devices> >> </domain> >> >> >> The network definition: >> virsh # net-dumpxml br909 >> <network> >> <name>br909</name> >> <uuid>07319380-2025-cdcc-924a-149cd0370b56</uuid> >> <forward mode='bridge'/> >> <bridge name='br909' /> >> </network> >> >> >> And iperf result (client and server are on the same vlan and they are running on the same host) >> >> [ 5] local xx.xx.xx.xx port 5001 connected with xx.xx.xx.yy port 18396 >> [ 5] 0.0-30.1 sec 35.4 MBytes 9.87 Mbits/sec > > Hm, strange. What does: > > tc class show dev vnet43 > tc filter show dev vnet43 > tc qdisc show dev vnet43 > > show? you can use this command to list the filter: tc filter list dev vnet43 root and check the mtu , and also read this:http://www.redhat.com/archives/libvir-list/2011-August/msg00333.html as i know,the libvirt0.9.10 has this problem,while the mtu has been set to 64k in libvirt dev version