I found that iperf still had several bugs, some of these involving the DCCP support. The bugs have been fixed and the updated version of iperf has been uploaded to http://www.erg.abdn.ac.uk/users/gerrit/dccp/apps/#iperf A tarball with all changes is on http://www.erg.abdn.ac.uk/users/gerrit/dccp/apps/iperf/zip/iperf-2.0.2_DCCP-patched-CBR-continuous.tar.bz2 (NB - test tree also updated today). Details of changes: ------------------- * fixed counting bugs when DCCP was used in packet-oriented mode (now the packet count is correct and works across UDP/DCCP); * enabled UDP-like reporting of statistics also for DCCP; * rewrote the algorithm to compute the inter-packet-gap in CBR mode: - in DCCP it tried to stuff the pipe without accounting for the time it spent, thus producing more packets than specified; - in tests this was observed to cause overflow; - the algorithm now measures the actual inter-packet gap of each packet and compares it to the target; adjusting for each send time; - it is more accurate than the previous implementation, in particular so for DCCP. * replaced the delay_loop(), which was using a spin-loop of constantly calling gettimeofday(), with nanosleep(). While the spinloop worked reasonably in many cases, it sometimes caused unwanted delays of 50milliseconds or more (process preempted?); it does not block signals like nanosleep; and nanosleep uses the hrtimers interface internally (/usr/src/davem-2.6/Documentation/hrtimers/hrtimers.txt) * separated setting TCP window size and SO_{RCV,SND}BUF settings; * completely overhauled the IPv6 support, it is in the order of 359 insertions versus 759 deletions; the -V flag is no longer necessary - iperf can now take any v4/v6 hostname, v4/v6 literal address. This required a minor change for the dual test and the tradeoff test (options -2 and -r): they no longer do a check for the reverse-lookup when the reverse connection comes in, instead the peer address is copied from the connection, which will do in almost any conceivable case (doing a reverse lookup leads to complications since it requires complex case distinctions of v4/v6-mapped-v6/v6 addresses). * IPv4 multicast support did not work well when the server-bind argument (-B) was used on a host with multiple interfaces. This has now been fixed for both IPv4 and IPv6 multicast using the `-j' `-J' arguments (for join-interface). For example: iperf -s -u -B 224.1.2.3 # works if there is only one interface iperf -s -u -B 224.1.2.3 -j eth1 # wanted to join on that one iperf -s -u -B FF00::c0de -J eth2 # IPv6 multicast, same semantics Hence if anyone is using iperf for DCCP, using the new version is much encouraged, as it will produce more reliable and accurate results. Still - when encountering any problems with this version of iperf, please do report these. - To unsubscribe from this list: send the line "unsubscribe dccp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
