#62 Issue in when using -l option and multiple TCP streams

v1.0 (example)
open
nobody
None
5
2014-08-13
2013-10-19
Rurre
No

If using the -l option together with multiple TCP streams then at the end of the data transfer the iperf displays the report for only one stream. There is no report for the other n-1 streams nor for the total sum of all streams.

Looking in Wireshark, it appeared that iperf server sent at the end of the data transfer a TCP FIN only for one stream, so the other n-1 streams remained open and then the report displayed by the iperf was for only that terminated TCP stream.

The issue does not appear if using -l with one single TCP stream, nor if using multiple TCP streams without -l option, so for having this problem it is needed to use -l option AND more than one TCP stream (-P <nb streams="" greater="" than="" 1="">).

C:\Tools\iperf>iperf -c 127.0.0.1 -l 1300 -P 3

Client connecting to 127.0.0.1, TCP port 5001
TCP window size: 64.0 KByte (default)


[ 4] local 127.0.0.1 port 53773 connected with 127.0.0.1 port 5001
[ 5] local 127.0.0.1 port 53774 connected with 127.0.0.1 port 5001
[ 3] local 127.0.0.1 port 53772 connected with 127.0.0.1 port 5001
[ ID] Interval Transfer Bandwidth
[ 3] 0.0-10.0 sec 277 MBytes 232 Mbits/sec

C:\Tools\iperf>iperf -s

Server listening on TCP port 5001
TCP window size: 64.0 KByte (default)


[ 4] local 127.0.0.1 port 5001 connected with 127.0.0.1 port 53772
[ 5] local 127.0.0.1 port 5001 connected with 127.0.0.1 port 53773
[ 6] local 127.0.0.1 port 5001 connected with 127.0.0.1 port 53774
[ ID] Interval Transfer Bandwidth
[ 4] 0.0-10.0 sec 277 MBytes 232 Mbits/sec

iperf version used 2.0.5 (same behavior if using Win or Linux iperf clients and or servers)

Discussion

  • Rurre
    Rurre
    2013-10-19

    Typo: 'Looking in Wireshark, it appeared that iperf server sent...' should be:
    Looking in Wireshark, it appeared that iperf CLIENT sent...'