I think there is insufficient information here to make any meaningful educated guesses. Can you try with iperf 2.0.13 an use the -e option on both the client and server? Also, show the whole command line and describe the test setup, interconnecting networks, and all descriptions of competing traffic. Also, try a 10 millisecond report interval, i.e. -i 0.01 (not sure if iperf 3 support this.)
Bob On Thu, Aug 8, 2019 at 9:03 AM Osdoba, Sascha <s.osd...@gsi.de> wrote: > Dear all, > > i am a newbie to iperf but I see a very wide bandwidth spreading to one of > our linux clients. > Tested it also against some other linux and windows server the bandwidth > is more common. > > iperf 3.7 (cJSON 1.5.2) > CYGWIN_NT-10.0-14393 citpc001 3.0.7-338.x86_64 2019-04-30 18:08 UTC x86_64 > > Done the tests one after another and there are such different values I > could not believe the results. > > Windows as server and Linux & Windows as server (on linux ver 3.6 was > used) but this not an answer because > the other linux server was more constant.. > > Any idea on that? If > > > Replaced hostnames and IP with A & B. > > Log: > > warning: Ignoring nonsense TCP MSS 0 > Connecting to host A, port 5201 > [ 5] local IP B port 55218 connected to IP A port 5201 > [ ID] Interval Transfer Bitrate > [ 5] 0.00-1.00 sec 22.0 MBytes 184 Mbits/sec > [ 5] 1.00-2.00 sec 11.4 MBytes 95.5 Mbits/sec > [ 5] 2.00-3.00 sec 21.2 MBytes 178 Mbits/sec > [ 5] 3.00-4.00 sec 21.1 MBytes 177 Mbits/sec > [ 5] 4.00-5.00 sec 12.4 MBytes 104 Mbits/sec > [ 5] 5.00-6.00 sec 10.2 MBytes 86.0 Mbits/sec > [ 5] 6.00-7.00 sec 10.9 MBytes 91.2 Mbits/sec > [ 5] 7.00-8.00 sec 11.1 MBytes 93.3 Mbits/sec > [ 5] 8.00-9.00 sec 18.6 MBytes 156 Mbits/sec > [ 5] 9.00-10.00 sec 8.00 MBytes 67.1 Mbits/sec > - - - - - - - - - - - - - - - - - - - - - - - - - > [ ID] Interval Transfer Bitrate > [ 5] 0.00-10.00 sec 147 MBytes 123 Mbits/sec > sender > [ 5] 0.00-10.05 sec 147 MBytes 123 Mbits/sec > receiver > > iperf Done. > > ------------------ > > warning: Ignoring nonsense TCP MSS 0 > Connecting to host A, port 5201 > [ 5] local IP B port 55225 connected to IP A port 5201 > [ ID] Interval Transfer Bitrate > [ 5] 0.00-1.00 sec 114 MBytes 957 Mbits/sec > [ 5] 1.00-2.00 sec 112 MBytes 942 Mbits/sec > [ 5] 2.00-3.00 sec 112 MBytes 942 Mbits/sec > [ 5] 3.00-4.00 sec 112 MBytes 941 Mbits/sec > [ 5] 4.00-5.00 sec 112 MBytes 943 Mbits/sec > [ 5] 5.00-6.00 sec 112 MBytes 942 Mbits/sec > [ 5] 6.00-7.00 sec 112 MBytes 942 Mbits/sec > [ 5] 7.00-8.00 sec 112 MBytes 942 Mbits/sec > [ 5] 8.00-9.00 sec 112 MBytes 942 Mbits/sec > [ 5] 9.00-10.00 sec 112 MBytes 943 Mbits/sec > - - - - - - - - - - - - - - - - - - - - - - - - - > [ ID] Interval Transfer Bitrate > [ 5] 0.00-10.00 sec 1.10 GBytes 944 Mbits/sec > sender > [ 5] 0.00-10.06 sec 1.10 GBytes 938 Mbits/sec > receiver > > iperf Done. > > ------- > > warning: Ignoring nonsense TCP MSS 0 > Connecting to host A, port 5201 > [ 5] local IP B port 55227 connected to IP A port 5201 > [ ID] Interval Transfer Bitrate > [ 5] 0.00-1.00 sec 2.75 MBytes 23.1 Mbits/sec > [ 5] 1.00-2.00 sec 2.88 MBytes 24.1 Mbits/sec > [ 5] 2.00-3.00 sec 17.4 MBytes 146 Mbits/sec > [ 5] 3.00-4.00 sec 10.6 MBytes 89.2 Mbits/sec > [ 5] 4.00-5.00 sec 24.5 MBytes 206 Mbits/sec > [ 5] 5.00-6.00 sec 18.9 MBytes 158 Mbits/sec > [ 5] 6.00-7.00 sec 12.6 MBytes 106 Mbits/sec > [ 5] 7.00-8.00 sec 9.75 MBytes 81.8 Mbits/sec > [ 5] 8.00-9.00 sec 18.1 MBytes 152 Mbits/sec > [ 5] 9.00-10.00 sec 18.1 MBytes 152 Mbits/sec > - - - - - - - - - - - - - - - - - - - - - - - - - > [ ID] Interval Transfer Bitrate > [ 5] 0.00-10.00 sec 136 MBytes 114 Mbits/sec > sender > [ 5] 0.00-10.05 sec 135 MBytes 113 Mbits/sec > receiver > > iperf Done. > > > > Regards Sascha > > > > _______________________________________________ > Iperf-users mailing list > Iperf-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/iperf-users >
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