[Iperf-users] iperf 2.0.5 tcp retransmission

[Sergey N. <skn...@gm...>]

Hello.

I have a following issue:
iperf (in my case 2.0.5) in tcp dual mode sometimes hangs if tested
device were under heavy load.

Here is iperf's output:
20110815214122,192.168.6.1,60007,192.168.106.1,57712,4,0.0-1.0,27527088,220216704
20110815214122,192.168.6.1,39787,192.168.106.1,61007,5,0.0-1.0,18350080,146800640
20110815214123,192.168.6.1,60007,192.168.106.1,57712,4,1.0-2.0,22610520,180884160
20110815214123,192.168.6.1,39787,192.168.106.1,61007,5,1.0-2.0,20971520,167772160
20110815214124,192.168.6.1,60007,192.168.106.1,57712,4,2.0-3.0,24495816,195966528
20110815214124,192.168.6.1,39787,192.168.106.1,61007,5,2.0-3.0,20971520,167772160
20110815214125,192.168.6.1,39787,192.168.106.1,61007,5,3.0-4.0,22937600,183500800
20110815214125,192.168.6.1,60007,192.168.106.1,57712,4,3.0-4.0,30018488,240147904
20110815214126,192.168.6.1,39787,192.168.106.1,61007,5,4.0-5.0,28835840,230686720
20110815214129,192.168.6.1,39787,192.168.106.1,61007,5,5.0-6.0,47185920,377487360
20110815214129,192.168.6.1,60007,192.168.106.1,57712,4,4.0-5.0,34471088,275768704
20110815214129,192.168.6.1,60007,192.168.106.1,57712,4,5.0-6.0,11232136,89857088
20110815214129,192.168.6.1,60007,192.168.106.1,57712,4,6.0-7.0,0,0
20110815214129,192.168.6.1,60007,192.168.106.1,57712,4,7.0-8.0,42329384,338635072
20110815214130,192.168.6.1,60007,192.168.106.1,57712,4,8.0-9.0,53625232,429001856
20110815214131,192.168.6.1,60007,192.168.106.1,57712,4,9.0-10.0,49195800,393566400
20110815214132,192.168.6.1,60007,192.168.106.1,57712,4,10.0-11.0,52193160,417545280
20110815214133,192.168.6.1,60007,192.168.106.1,57712,4,11.0-12.0,51997680,415981440
20110815214134,192.168.6.1,60007,192.168.106.1,57712,4,12.0-13.0,51721112,413768896
20110815214135,192.168.6.1,60007,192.168.106.1,57712,4,13.0-14.0,48434152,387473216
20110815214136,192.168.6.1,60007,192.168.106.1,57712,4,14.0-15.0,54339096,434712768
20110815214137,192.168.6.1,60007,192.168.106.1,57712,4,15.0-16.0,53757000,430056000
20110815214138,192.168.6.1,60007,192.168.106.1,57712,4,16.0-17.0,53128568,425028544
20110815214139,192.168.6.1,60007,192.168.106.1,57712,4,17.0-18.0,53277712,426221696
20110815214140,192.168.6.1,60007,192.168.106.1,57712,4,18.0-19.0,53366040,426928320
20110815214141,192.168.6.1,60007,192.168.106.1,57712,4,19.0-20.0,52500136,420001088
20110815214141,192.168.6.1,60007,192.168.106.1,57712,4,0.0-20.0,821428224,328199947

We can see that iperf[5] (receiver) worked till 6th second and then
only iperf[4] (sender) remained to work. If this happened then iperf
client hangs. It looks like iperf client does not retransmit lost
packages.

Have anybody dealed with it?

Thanks in advance,
Sergey Naumov.