I've got a fix for this bug, please try iperf version 2.0.4-3, it will be available in the Debian mirrors soon.
I've tested it in several Linux boxes with different kernels, TCP and UDP mode, with -d (bidirectional test) and without it, and now the CPU usage is very low. Thanks a lot for your bug report. Regards, Roberto Lumbreras -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]