On Tue, Jul 16, 2019 at 07:02:29PM +0530, Sriram Vatala via dev wrote: > OVS may be unable to transmit packets for multiple reasons and > today there is a single counter to track packets dropped due to > any of those reasons. The most common reason is that a VM is > unable to read packets fast enough causing the vhostuser port > transmit queue on the OVS side to become full. This manifests > as a problem with VNFs not receiving all packets. Having a > separate drop counter to track packets dropped because the > transmit queue is full will clearly indicate that the problem > is on the VM side and not in OVS. Similarly maintaining separate > counters for all possible drops helps in indicating sensible > cause for packet drops. > > This patch adds counters to track packets dropped due to all > possible reasons and these counters are displayed along with > other stats in "ovs-vsctl get interface <iface> statistics" > command. The detailed stats will be available for both dpdk and > vhostuser ports.
Did you consider using netdev_get_custom_stats() for these counters? I do not know whether they are likely to be implemented by other network devices, and custom stats are an appropriate way to implement specialized statistics. > Following are the details of the new counters : > > tx_failed_drops : Sometimes DPDK physical/vHost port transmit > API fails to send all/some packets. These untransmited packets > are dropped.The most likely reason for this to happen is > because of transmit queue overrun. Besides transmit queue > overrun, there are other unlikely reasons such as invalid > queue id etc. > > tx_mtu_exceeded_drops : These are the packets dropped due > to MTU mismatch (i.e Pkt len > Max Dev MTU). > > tx_qos_drops/rx_qos_drops : These are the packets dropped due > to transmission/reception rate exceeding the configured > Egress/Ingress policer rate on the interface. It would make sense to include the above descriptions in vswitchd/vswitch.xml alongside the other statistics under the "Statistics" group for the Interface table. Thanks for working to make OVS better! _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
