At least, you have to flush non-PMD threads too. Best regards, Ilya Maximets.
On 18.06.2017 22:56, Bhanuprakash Bodireddy wrote: > Under low rate traffic conditions, there can be 2 issues. > (1) Packets potentially can get stuck in the intermediate queue. > (2) Latency of the packets can increase significantly due to > buffering in intermediate queue. > > This commit handles the (1) issue by flushing the tx port queues from > PMD processing loop. Also this commit addresses issue (2) by flushing > the tx queues after every rxq port processing. This reduces the latency > with out impacting the forwarding throughput. > > MASTER > -------- > Pkt size min(ns) avg(ns) max(ns) > 512 4,631 5,022 309,914 > 1024 5,545 5,749 104,294 > 1280 5,978 6,159 45,306 > 1518 6,419 6,774 946,850 > > MASTER + COMMIT > ----------------- > Pkt size min(ns) avg(ns) max(ns) > 512 4,711 5,064 182,477 > 1024 5,601 5,888 701,654 > 1280 6,018 6,491 533,037 > 1518 6,467 6,734 312,471 > > PMDs can be teared down and spawned at runtime and so the rxq and txq > mapping of the PMD threads can change. In few cases packets can get > stuck in the queue due to reconfiguration and this commit helps flush > the queues. > > Suggested-by: Eelco Chaudron <echau...@redhat.com> > Reported-at: > https://mail.openvswitch.org/pipermail/ovs-dev/2017-April/331039.html > Signed-off-by: Bhanuprakash Bodireddy <bhanuprakash.bodire...@intel.com> > Signed-off-by: Antonio Fischetti <antonio.fische...@intel.com> > Co-authored-by: Antonio Fischetti <antonio.fische...@intel.com> > Signed-off-by: Markus Magnusson <markus.magnus...@ericsson.com> > Co-authored-by: Markus Magnusson <markus.magnus...@ericsson.com> > Acked-by: Eelco Chaudron <echau...@redhat.com> > --- > lib/dpif-netdev.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c > index d59208e..dfd88aa 100644 > --- a/lib/dpif-netdev.c > +++ b/lib/dpif-netdev.c > @@ -3761,6 +3761,8 @@ reload: > for (i = 0; i < poll_cnt; i++) { > dp_netdev_process_rxq_port(pmd, poll_list[i].rx, > poll_list[i].port_no); > + > + dp_netdev_flush_txq_ports(pmd); > } > > if (lc++ > 1024) { > @@ -3781,6 +3783,9 @@ reload: > } > } > > + /* Flush the queues as part of reconfiguration logic. */ > + dp_netdev_flush_txq_ports(pmd); > + > poll_cnt = pmd_load_queues_and_ports(pmd, &poll_list); > exiting = latch_is_set(&pmd->exit_latch); > /* Signal here to make sure the pmd finishes > _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
