Hello, I observed that the latest OVS with dpdk-1.8.0 and igb_uio starts to drop packets earlier than a regular Linux ixgbe 10G interface, setup follows:
receiver/forwarder: - 8 core/2 head system with E5-2603v2, cores 1-3 are given to OVS exclusively - n-dpdk-rxqs=6, rx scattering is not enabled - x520 da - 3.10/3.18 host kernel - during 'legacy mode' testing, queue interrupts are scattered through all cores sender: - 16-core E52630, netmap framework for packet generation - pkt-gen -f tx -i eth2 -s 10.6.9.0-10.6.9.255 -d 10.6.10.0-10.6.10.255 -S 90:e2:ba:84:19:a0 -D 90:e2:ba:85:06:07 -R 11000000, results in 11Mpps 60-byte packet flood, there are constant values during test. OVS contains only single drop rule at the moment: ovs-ofctl add-flow br0 in_port=1,actions=DROP Packet generator was launched for tens of seconds for both Linux stack and OVS+DPDK cases, resulting in zero drop/error count on the interface in first, along with same counter values on pktgen and host interface stat (means that the none of generated packets are unaccounted). I selected rate for about 11M because OVS starts to do packet drop around this value, after same short test interface stat shows following: statistics : {collisions=0, rx_bytes=22003928768, rx_crc_err=0, rx_dropped=0, rx_errors=10694693, rx_frame_err=0, rx_over_err=0, rx_packets=343811387, tx_bytes=0, tx_dropped=0, tx_errors=0, tx_packets=0} pktgen side: Sent 354506080 packets, 60 bytes each, in 32.23 seconds. Speed: 11.00 Mpps Bandwidth: 5.28 Gbps (raw 7.39 Gbps) If rate will be increased up to 13-14Mpps, the relative error/overall ratio will rise up to a one third. So far OVS on dpdk shows perfect results and I do not want to reject this solution due to exhaustive behavior like described one, so I`m open for any suggestions to improve the situation (except using 1.7 branch :) ).