Hello, We found what was the issue there. Our OVS bridge had set datapath_type=NETDEV. Change it to SYSTEM fixed our issue :)
Pozdrawiam / Best regards Sławek Kapłoński [email protected] > Wiadomość napisana przez Sławomir Kapłoński <[email protected]> w dniu > 12.05.2017, o godz. 16:40: > > Hello, > > I have some problem with poor network performance on libvirt with qemu and > openvswitch. > I’m using libvirt 1.3.1, qemu 2.5 and openvswitch 2.6.0 on Ubuntu 16.04 > currently. > My connection diagram looks like below: > > > +---------------------------+ > +---------------------------+ > | Net namespace | > +------------------+ | OVS bridge | > | | > | | | | > | | > | VM | | | > | | > | | +----+---+ +----+-----+ > +----+---+ | > | +------+tap dev | | veth A +---------+ > veth B | | > | | +--------+ +----------+ > +--------+ | > | iperf > -s<---------------------------------------------------------------------------+iperf > -c | > | | | | > | | > +------------------+ | | > | | > | | > | | > +---------------------------+ > +---------------------------+ > > > > I haven’t got any QoS in tc configured on any interface. When I do this iperf > test I have something about 150Mbps only. IMHO it should be something about > 20-30 Gbps there. > > Other strange thing is that if I made more such VMS (each connected in same > way, with own OVS bridge and own namespace) bandwidth is lower for each of > them and it looks for me that summarize bandwidth is then something about > 1Gbps (30 VMs - each got something about 30Mbps in such test). > > When I removed VM and added „tap dev” as internal port in OVS and made same > test, then I had result about 30 Gbps. > I have no idea what can be wrong there. Maybe someone of You had such > problems earlier? > > One more thing, on different host with Ubuntu 14.04, OVS 2.0.2, Libvirt 1.3.1 > and qemu 2.3 I don’t have this problem. > Kernel on both hosts is 4.4.0 (from Ubuntu repo). > > We also found that on Ubuntu 16.04 and OVS 2.6.0 something strange: > > 2017-05-12T14:22:04.350Z|00120|poll_loop|INFO|wakeup due to [POLLIN] on fd > 149 (AF_PACKET(tap27903b5e-06)(protocol=0x3)<->) at > ../lib/netdev-linux.c:1139 (86% CPU usage) > 2017-05-12T14:22:04.350Z|00121|poll_loop|INFO|wakeup due to [POLLIN] on fd > 149 (AF_PACKET(tap27903b5e-06)(protocol=0x3)<->) at > ../lib/netdev-linux.c:1139 (86% CPU usage) > 2017-05-12T14:22:04.351Z|00122|poll_loop|INFO|wakeup due to [POLLIN] on fd > 149 (AF_PACKET(tap27903b5e-06)(protocol=0x3)<->) at > ../lib/netdev-linux.c:1139 (86% CPU usage) > 2017-05-12T14:22:04.351Z|00123|poll_loop|INFO|wakeup due to [POLLIN] on fd > 149 (AF_PACKET(tap27903b5e-06)(protocol=0x3)<->) at > ../lib/netdev-linux.c:1139 (86% CPU usage) > 2017-05-12T14:22:04.351Z|00124|poll_loop|INFO|wakeup due to [POLLIN] on fd > 149 (AF_PACKET(tap27903b5e-06)(protocol=0x3)<->) at > ../lib/netdev-linux.c:1139 (86% CPU usage) > 2017-05-12T14:22:04.351Z|00125|poll_loop|INFO|wakeup due to [POLLIN] on fd > 149 (AF_PACKET(tap27903b5e-06)(protocol=0x3)<->) at > ../lib/netdev-linux.c:1139 (86% CPU usage) > > > We also noticed that during network speed test ovs-vswitchd process is > running all time on 100% CPU (one process always). > Can it be some bug in OVS? > > Pozdrawiam / Best regards > Sławek Kapłoński > [email protected] > _______________________________________________ > discuss mailing list > [email protected] > https://mail.openvswitch.org/mailman/listinfo/ovs-discuss _______________________________________________ discuss mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-discuss
