On Tue, Jul 16, 2019 at 03:01:12PM +0530, Nilesh wrote: > Hello, > we are trying to send packets from the testpmd to another machine with > DPDK running. > We are building custom packets before sending it on the wire. > After running the application the TX-dropped is quite high (can be > inferred from following logs : ) > > > $ sudo ./testpmd -c f -w 01:00.1 -- --nb-cores=2 > --eth-peer=0,A4:BF:01:37:23:AB --rxq=1 --txq=1 > > > Port statistics ==================================== > ######################## NIC statistics for port 0 ######################## > RX-packets: 1445150 RX-missed: 0 RX-bytes: 86709064 > RX-errors: 0 > RX-nombuf: 0 > TX-packets: 1602045 TX-errors: 0 TX-bytes: 134571780 > > Throughput (since last show) > Rx-pps: 0 > Tx-pps: 0 > ############################################################################ > > ---------------------- Forward statistics for port 0 ---------------------- > RX-packets: 1445160 RX-dropped: 0 RX-total: 1445160 > TX-packets: 1602045 TX-dropped: 694971472 TX-total: 696573517 > ---------------------------------------------------------------------------- > > +++++++++++++++ Accumulated forward statistics for all ports+++++++++++++++ > RX-packets: 1445160 RX-dropped: 0 RX-total: 1445160 > TX-packets: 1602045 TX-dropped: 694971472 TX-total: 696573517 > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > > > What could be the reason for such packet drop? What tuning of buffer/queue > size affects this ? >
Those stats for TX-dropped just look wrong to me. Given that you received only 1.45 million packets, having dropped nearly 700 million doesn't make sense. Even the Tx packet counts - though more reasonable - are higher than the received count. In terms of testpmd settings, the rxq=1 and txq=1 settings are the default so aren't needed, and setting the number of forwarding cores to 2 shouldn't do anything as there is only a single receive queue which can't be shared among cores. Regards, /Bruce
