Excerpts from Vasanthy Kolluri (vkolluri)'s message of Mon Mar 21 13:49:45 -0500 2011: > I have two iperf clients sending UDP packets to a iperf server. Once the > test is completed, the Server side results for only one of the streams > is reported both on the client and server. > > > > Iperf client: > > > > # iperf -c 10.0.50.100 -B 10.0.50.1 -u -b1G -t100 & > > # iperf -c 10.0.50.100 -B 10.0.50.2 -u -b1G -t100 &
This isn't the common way to do multiple streams with Iperf and I suspect the code won't deal with this gracefully. In this case I believe Iperf is silently failing. Iperf3 handles this case by only allowing one client at a time and rejects other clients until tests are complete. Are you running the two client processes on different machines or the same machine? I see that you're binding (-B) to two different IP addresses but that could be two NICs on the same machine or could be on different machines. If you are running on two machines you'll be best off starting two Iperf servers on the server end, eg: iperf -u -s -p 5001 iperf -u -s -p 5002 and then on each of the client machines doing: iperf -c 10.0.50.100 -u -b1G -t100 -p 5001 iperf -c 10.0.50.100 -u -b1G -t100 -p 5002 If both clients are on the same machine you can do: iperf -c 10.0.50.100 -u -b1G -t100 -P2 (just use your original Iperf invocation on the server side) The -P flag spawns 2 threads each trying to send at 1G/s. Modern hardware should have no trouble doing 2 x 1G UDP streams on a 10G NIC. It's often hard to get UDP working faster than 8-9G/s for a variety of reasons as you usually end up buring a lot of CPU to receive them. Hope that helps, Jon ------------------------------------------------------------------------------ Enable your software for Intel(R) Active Management Technology to meet the growing manageability and security demands of your customers. Businesses are taking advantage of Intel(R) vPro (TM) technology - will your software be a part of the solution? Download the Intel(R) Manageability Checker today! http://p.sf.net/sfu/intel-dev2devmar _______________________________________________ Iperf-users mailing list Iperf-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/iperf-users