Hi Onkar, Thanks for shedding some light.
I don't think your difference in performance will have to do your OvS-DPDK setup. If you're taking the measurements directly from the iperf server side you'd be going through the "Internet". Assuming you don't have a dedicated connection there, things like your connection's bandwidth, the RTT from end to end start to matter considerably, specially for TCP. To get to the bottom of it I'd advise you to take the iperf server and connect it directly to the first machine (Machine 1). You would be excluding any "Internet" interference and be able to get the performance of a pvp scenario first. Assuming you're using kernel forwarding inside the VMs, if you want to squeeze in the extra performance it is probably wise to use DPDK testpmd to forward the traffic inside of the VMs as well, as explained here: http://docs.openvswitch.org/en/latest/howto/dpdk/#phy-vm-phy-vhost-loopback Regards, Tiago. On 04/10/2018 21:06, Onkar Pednekar wrote: > Hi Tiago, > > Thanks for your reply. > > Below are the answers to your questions in-line. > > > On Thu, Oct 4, 2018 at 4:07 AM Lam, Tiago <[email protected] > <mailto:[email protected]>> wrote: > > Hi Onkar, > > Thanks for your email. Your setup isn't very clear to me, so a few > queries in-line. > > On 04/10/2018 06:06, Onkar Pednekar wrote: > > Hi, > > > > I have been experimenting with OVS DPDK on 1G interfaces. The > system has > > 8 cores (hyperthreading enabled) mix of dpdk and non-dpdk capable > ports, > > but the data traffic runs only on dpdk ports. > > > > DPDK ports are backed by vhost user netdev and I have configured the > > system so that hugepages are enabled, CPU cores isolated with PMD > > threads allocated to them and also pinning the VCPUs.> > > When I run UDP traffic, I see ~ 1G throughput on dpdk interfaces > with < > > 1% packet loss. However, with tcp traffic, I see around 300Mbps > > thoughput. I see that setting generic receive offload to off > helps, but > > still the TCP thpt is very less compared to the nic capabilities. > I know > > that there will be some performance degradation for TCP as against UDP > > but this is way below expected. > > > > When transmitting traffic between the DPDK ports, what are the flows you > have setup? Does it follow a p2p or pvp setup? In other words, does the > traffic flow between the VM and the physical ports, or only between > physical ports? > > > The traffic is between the VM and the physical ports. > > > > I don't see any packets dropped for tcp on the internal VM (virtual) > > interfaces. > > > > I would like to know if there is an settings (offloads) for the > > interfaces or any other config I might be missing. > > What is the MTU set on the DPDK ports? Both physical and vhost-user? > > $ ovs-vsctl get Interface [dpdk0|vhostuserclient0] mtu > > > MTU set on physical ports = 2000 > MTU set on vhostuser ports = 1500 > > > This will help to clarify some doubts around your setup first. > > Tiago. > > > > > Thanks, > > Onkar > > > > > > _______________________________________________ > > discuss mailing list > > [email protected] <mailto:[email protected]> > > https://mail.openvswitch.org/mailman/listinfo/ovs-discuss > > > _______________________________________________ discuss mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-discuss
