RAKOTOSALAMA, Nirilanto wrote: > Hello, >=20 > In order to test rtcap+wireshark perf to see if it could analize a full= loaded traffic, > I ran a simple program that sends n UDP packets of 1 kBytes from a box = (xenomai 2.3.1+ rtnet 0.9.9+ e1000) > to another (xenomai 2.3.1+ rtnet 0.9.9+ eepro100 + rtcap + wireshark). > Packets are sent without delay between each of them. > If more than 100 packets are sent, wireshark only shows 82 captured pac= kets and rt_sendmsg function doesn't=20 > return any error. > What could be the source of this loss ?=20 > Is it sure that packets are really sent ? Is there a means to know how = many packet did the NIC really send ? > Did rt_dev_sendmsg return error if NIC has not enough buffer space at d= river layer or below ?
If you are sending at a very high rate, you may temporarily overload the sniffer. That may mean the RT queues overflow (not likely if both boxes have similar performance) or Linux fails to process all sniffed packets in time (because the RT load is too high. Check the drop counter under "ifconfig rteth0", maybe it is non-zero. Still, there are 128 buffers in the rtcap pool by default (module parameter "rtcap_rtskbs" or rtcap.ko). Also check if there are any suspicious error messages on any kernel console of both boxes. Jan
signature.asc
Description: OpenPGP digital signature
------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/
_______________________________________________ RTnet-users mailing list RTnet-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/rtnet-users
