On Fri, Apr 10, 2009 at 08:46:08AM +0200, Bjoern Koenig wrote: > I wrote: > > > >> If you can easily reproduce the issue, can you capture stalled TCP > >> session with tcpdump on receiving host?(Make sure to disable Rx > >> checksum offload prior to capturing the session.) > > > > I transferred a 256 kiB file and these are the tcpdumps: > > > > http://www.alpha-tierchen.de/~bkoenig/fxp0-with-tso.txt > > http://www.alpha-tierchen.de/~bkoenig/fxp0-without-tso.txt > > > > Actually the transfer doesn't stall although ftp and scp told me so. It > > becomes incredibly slow. It seems like that the chunks are too large and a > > smaller packet will be resent. I decreased the MTU from 1500 to 1492 and > > it works fine with TSO enabled. > > > > I also captured the traffic on my router: > > > > http://www.alpha-tierchen.de/~bkoenig/fxp0-with-tso-router.txt > > http://www.alpha-tierchen.de/~bkoenig/fxp0-without-tso-router.txt > > > > It reveals a suspect information: "truncated-ip - 8 bytes missing!" > > > > I almost suppose that this is a PPPoE-related configuration issue and the > > fxp driver is not necessarily the problem since decreasing the MTU of the > > LAN host solves it. > > Hello, it's me again. :) > > It's not PPPoE-related. I was able to reproduce the behaviour within a > regular LAN from host to host. I also have another symptom which denies > the PPPoE assumption: > > If I set MTU to value X then it doesn't work with MTU X+N anymore. I'll > get the message "N bytes missing!" in the tcpdump output. For example: > > ifconfig fxp0 mtu 1448 # works > ifconfig fxp0 mtu 1412 # still works > ifconfig fxp0 mtu 1448 # doesn't work (36 bytes missing) > ifconfig fxp0 mtu 1400 # works > ifconfig fxp0 mtu 1412 # doesn't work (12 bytes missing) >
Hmm, I can't reproduce this. Can you send me a URL to captured data for broken case? _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"
