On Wed, May 30, 2018 at 5:20 AM Jesper Dangaard Brouer <bro...@redhat.com> wrote:
> On Mon, 28 May 2018 09:09:17 -0700 > Eric Dumazet <eric.duma...@gmail.com> wrote: > > Tariq, here are my test results : No drops for me. > > > > # ./netperf -H 2607:f8b0:8099:e18:: -t UDP_STREAM > > MIGRATED UDP STREAM TEST from ::0 (::) port 0 AF_INET6 to 2607:f8b0:8099:e18:: () port 0 AF_INET6 > > Socket Message Elapsed Messages > > Size Size Time Okay Errors Throughput > > bytes bytes secs # # 10^6bits/sec > > > > 212992 65507 10.00 202117 0 10592.00 > > 212992 10.00 0 0.00 > Hmm... Eric the above result show that ALL your UDP packets were dropped! > You have 0 okay messages and 0.00 Mbit/s throughput. > It needs to look like below (test on i40e NIC): > $ netperf -t UDP_STREAM -H fee0:cafe::1 > MIGRATED UDP STREAM TEST from ::0 (::) port 0 AF_INET6 to fee0:cafe::1 () port 0 AF_INET6 : histogram : demo > Socket Message Elapsed Messages > Size Size Time Okay Errors Throughput > bytes bytes secs # # 10^6bits/sec > 212992 65507 10.00 186385 0 9767.08 > 212992 10.00 186385 9767.08 > If I manually instruct ip6tables to drop all UDP packets, then I get > what you see... so, something on your test system are likely dropping > your UDP packets, but letting regular netperf (TCP) control > communication through. > # ip6tables -I INPUT -p udp -j DROP > $ netperf -t UDP_STREAM -H fee0:cafe::1 > MIGRATED UDP STREAM TEST from ::0 (::) port 0 AF_INET6 to fee0:cafe::1 () port 0 AF_INET6 : histogram : demo > Socket Message Elapsed Messages > Size Size Time Okay Errors Throughput > bytes bytes secs # # 10^6bits/sec > 212992 65507 10.00 182095 0 9542.41 > 212992 10.00 0 0.00 Right you are, for some reason I copied/pasted wrong results, after _specifically_ filling up the frags to the memory limits, when trying to reproduce 'bad numbers ' Here are the good ones, using latest David Miller net tree. ( plus https://patchwork.ozlabs.org/patch/922528/ but that should not matter here) llpaa23:/export/hda3/google/edumazet# ./netperf -H 2607:f8b0:8099:e18:: -t UDP_STREAM MIGRATED UDP STREAM TEST from ::0 (::) port 0 AF_INET6 to 2607:f8b0:8099:e18:: () port 0 AF_INET6 Socket Message Elapsed Messages Size Size Time Okay Errors Throughput bytes bytes secs # # 10^6bits/sec 212992 65507 10.00 216236 0 11331.89 212992 10.00 215068 11270.68 There are few drops because of the too small /proc/sys/net/core/rmem_default ( 212992 as seen in netperf output) for these kind of stress. ( each 64KB datagram actually consumes half the budget ...)
