Do you have jumbo frames enabled, or is that the default on 10Gb interfaces?
What's your CPU(s) doing during this process? Have you tried say a 1300 byte datagram? Lastly, the code to throttle using UDP uses a... "coarse" timer. Well, in CPU terms it's coarse. Have you tried simply specifying -u instead of -b? If -b is mandatory, you MAY have to tweak the code to use a finer timer in the throttling process. Disclaimer: I am a Network Engineer not a professional developer. I tweaked the source some years back to address a CPU usage issue when using "-b", and that was based on info from the web. I know a LITTLE about programming - but 100% NOT an expert by ANY stretch! I don't have 10Gb link so can't help test. -----Original Message----- From: Jimmy Cullen [mailto:[email protected]] Sent: Thursday, July 07, 2011 10:06 AM To: [email protected] Subject: [Iperf-users] iperf UDP on a 10 gigabit link Hi, I am using iperf-2.0.5 to measure UDP throughput on a 10 Gbps link, however test results do not go above 4.99 Gbps. When using TCP however the test shows 9.90 Gbps. Has anyone been able to operate iperf with UDP above 5 Gbps? Thanks, Jimmy jimmy@jbraid2:~/old/iperf-2.0.5/src$ ./iperf -u -c 192.168.10.101 -w 16M -b 10000m -l 8972 ------------------------------------------------------------ Client connecting to 192.168.10.101, UDP port 5001 Sending 8972 byte datagrams UDP buffer size: 32.0 MByte (WARNING: requested 16.0 MByte) ------------------------------------------------------------ [ 3] local 192.168.10.103 port 42070 connected with 192.168.10.101 port 5001 [ ID] Interval Transfer Bandwidth [ 3] 0.0-10.0 sec 5.81 GBytes 4.99 Gbits/sec [ 3] Sent 695918 datagrams [ 3] Server Report: [ 3] 0.0-10.0 sec 5.81 GBytes 4.98 Gbits/sec 0.814 ms 0/695917 (0%) [ 3] 0.0-10.0 sec 1 datagrams received out-of-order jimmy@jbraid2:~/old/iperf-2.0.5/src$ ./iperf -w 16M -c 192.168.10.101 ------------------------------------------------------------ Client connecting to 192.168.10.101, TCP port 5001 TCP window size: 32.0 MByte (WARNING: requested 16.0 MByte) ------------------------------------------------------------ [ 3] local 192.168.10.103 port 48529 connected with 192.168.10.101 port 5001 [ ID] Interval Transfer Bandwidth [ 3] 0.0-10.0 sec 11.5 GBytes 9.90 Gbits/sec ------------------------------------------------------------------------------ All of the data generated in your IT infrastructure is seriously valuable. Why? It contains a definitive record of application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-d2d-c2 _______________________________________________ Iperf-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/iperf-users <font size="1"> <div style='border:none;border-bottom:double windowtext 2.25pt;padding:0in 0in 1.0pt 0in'> </div> "This email is intended to be reviewed by only the intended recipient and may contain information that is privileged and/or confidential. If you are not the intended recipient, you are hereby notified that any review, use, dissemination, disclosure or copying of this email and its attachments, if any, is strictly prohibited. If you have received this email in error, please immediately notify the sender by return email and delete this email from your system." </font> ------------------------------------------------------------------------------ All of the data generated in your IT infrastructure is seriously valuable. Why? It contains a definitive record of application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-d2d-c2 _______________________________________________ Iperf-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/iperf-users
