Hi I don´t know if this message is OT, maybe slight OT, but I´m facing an interesting problem with UDP datagrams and Windows 7/2008 stack
Well, we have a scenario where a machine can´t receive over 30 mbits of UDP data on a local gigabit ethernet, and to make it worse, the whole windows TCP/IP stack becomes unstable, and I mean that because if we use ping 127.0.0.1 –t we see strange delays as 30ms, even 800ms! After a lot of researching on the problem, we found that some video equipments that we are receiving video (RTP over UDP), sends each packet of video from a different source port! The source port is always incremented for each packet the equipment sends, and there are about 50 equipments sending about 170 packets per second each equipment, giving a total of 2mbits of data per second per equipment. I made a little program to test such behaviour, I opened a server on a machine, listening on 50 UDP ports and a client on 4 different machines sending datagrams to this server. if I send the UDP packets all from the same source port (Same “connection”) I can receive over 200mbits of data easily, but if I change the client to send 1 packet per source port (By calling Close and Connect each time I send a new UDP packet) then, the server will not be able to receive more than 30mbits and ping 127.0.0.1 –t from the server will start delaying to 5~10ms. I believe that this is something related to windows 7/2008 IP stack implementation, does anybody have an idea on why does this happens? Maybe the overhead of managing packets from different source ports is too high! Oh, I´m using TWSocket to receive UDP data Thanks! Éric -- To unsubscribe or change your settings for TWSocket mailing list please goto http://lists.elists.org/cgi-bin/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
