Hi, 100Mbps is a maximum. TCP puts a bit of protocol and processing overhead on it. 86.6Mbps is whit I would expect from a couple of 100MBps Ethernet cards running on a cheep layer 2 (simple) switch. Try running the test for longer (to overcome slowstart) or use UDP (which has less over head and no slow start) then number will be closer to 100mbps.
Slowstart should not be two much of a problem on a LAN as the latency will be quite low. Also after changing the tcpwindow size you need to restart networking services on both computers for the change to TCP window to take effect (depending on your stack implementation). Restart the computer if you are unsure over how to do this. Regards, Owain -----Original Message----- From: Frank Schuster [mailto:frank.schuste...@web.de] Sent: 23 October 2009 08:32 To: iperf-users@lists.sourceforge.net Subject: [Iperf-users] IPerf 2.0.8 Dualtest Hello, I have done a dualtest with iperf: On server I execute: iperf -s And on client: iperf -c <server_ip> -d The output shows me in addition more bandwidth than my network (100MBit/s) has: [ 5] 0.0-10.0 sec 103 MBytes 86.6 Mbits/sec [ 4] 0.0-10.0 sec 101 MBytes 84.4 Mbits/sec That is approxiametly 170 MBits/sec and not 100 MBit in maximum. I searched the web for the problem, but the only reason I found is the window size. I changed it between 50 kb and 1500 kb on client and server but it has no effect (perhaps 5MBit/s). Is there an other explaination for my problem? Regards Frank ______________________________________________________ GRATIS für alle WEB.DE-Nutzer: Die maxdome Movie-FLAT! Jetzt freischalten unter http://movieflat.web.de ------------------------------------------------------------------------------ Come build with us! The BlackBerry(R) Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9 - 12, 2009. Register now! http://p.sf.net/sfu/devconference _______________________________________________ Iperf-users mailing list Iperf-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/iperf-users This message should be regarded as confidential. If you have received this email in error please notify the sender and destroy it immediately. Statements of intent shall only become binding when confirmed in hard copy by an authorised signatory. The contents of this email may relate to dealings with other companies within the Detica Limited group of companies. Detica Limited is registered in England under No: 1337451. Registered offices: Surrey Research Park, Guildford, Surrey, GU2 7YP, England. ------------------------------------------------------------------------------ Come build with us! The BlackBerry(R) Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9 - 12, 2009. Register now! http://p.sf.net/sfu/devconference _______________________________________________ Iperf-users mailing list Iperf-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/iperf-users
