netperf builded with --enable-demo does not emit interim results during the run

[O-ring]

Hello everyone,

I have compiled netperf-2.7.0 on linux x86-64, with the following options:

sh configure --prefix=/usr --enable-demo --enable-histogram

I have observed that sometimes the partial result is not printed. Here is an example of the output:

Interim result: 31.07 10^6bits/s over 1.042 seconds ending at 1610397003.583
Interim result: 7.67 10^6bits/s over 4.051 seconds ending at 1610397007.634
Interim result: 3.69 10^6bits/s over 2.098 seconds ending at 1610397009.732
Interim result: 4.79 10^6bits/s over 1.068 seconds ending at 1610397010.799

Interim result: 11.19 10^6bits/s over 1.921 seconds ending at 1610314342.506
Interim result: 10.26 10^6bits/s over 1.495 seconds ending at 1610314344.001
Interim result: 7.29 10^6bits/s over 1.402 seconds ending at 1610314345.403
Interim result: 6.45 10^6bits/s over 1.137 seconds ending at 1610314346.540
Interim result: 2.99 10^6bits/s over 2.148 seconds ending at 1610314348.688
Interim result: 19.20 10^6bits/s over 455.831 seconds ending at 1610314804.519
netperf: get_sock_buffer: receive socket size determined to be 87380
netperf: get_sock_buffer: send socket size determined to be 1726560

Interim result: 9.82 10^6bits/s over 1.175 seconds ending at 1610066611.657
Interim result: 5.63 10^6bits/s over 1.746 seconds ending at 1610066613.403
Interim result: 3.18 10^6bits/s over 1.775 seconds ending at 1610066615.178
Interim result: 17.87 10^6bits/s over 403.530 seconds ending at 1610067018.708
netperf: get_sock_buffer: receive socket size determined to be 87380
netperf: get_sock_buffer: send socket size determined to be 4194304

this is an example command I use to run the executable:

netperf -H 10.24.15.6 -d 10 -l 600 -v 2 -D 1 -Y 104,104 -f m

I have a feeling that this problem pops up when there is a network connectivity problem (congestion).

Let me know if you need any other information to better detect this problem.