On Thu, Dec 15, 2011 at 03:16:51PM +0100, Andrea Venturoli wrote: > On 12/14/11 22:32, YongHyeon PYUN wrote: > > >>Wireshark showed some wrong checksums (I believe on the ICMP packet, but > >>I might remember wrong). > > > >You can check whether you received bad checksummed frames with > >netstat(1). > > I tried "netstat -ind", but it shows no Ierrs/Idrop/Oerrs/Odrop. >
Use -s option which will show statistics for each network protocols. Search 'discarded for bad checksums' from the output. > > > > > >Is simple downloading from client to server is enough to trigger > >the issue? > > Yes and no. > Depending on where the client is located (on the Internet) and/or the > protocol used, I get either failures or ridicuolous performance (i.e. > 58-60kB/s without TSO vs. 1-2kB/s with TSO). > > > > > > >Packet capture that shows the problem would be great to > >know what's going on here. > > I'll send them to you privately. > > You'll see tso.dump and notso.dump: they are both from the same client > downloading the same (random) file (the file name was changed only to > prevent possible caching). > See notso.dump is perfect, while tso.dump shows a lot of potential problems. > Thanks. > > > > > >>Would you try attached patch and let me know it goes? > >Sorry, it seems extra pull up for TCP payload may not be required > >here. Try this instead. > > I see a little increase in performance (2-3kB/s instead of 1-2kB/s); > this might however well depend on external factors. Still it is very > different from what I'm get without TSO. > Thanks for testing. Based on dump file, I tried various MTU configuration and I was not able to reproduce it. By chance, are you using firewall(pf/ipfw/ipf) or bridge(4)? If I remember correctly some firewall rules are not compatible with TSO. For bridge, if one member of bridge does not support TSO, TSO should be disabled. > > > bye & Thanks > av. > > P.S. I can live well without TSO; I'm just doing this to let the > software improve. Go ahead only if *you* are interested. I do care driver stability so it would be great if I manage to address the issue. :-) _______________________________________________ freebsd-net@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-net To unsubscribe, send any mail to "freebsd-net-unsubscr...@freebsd.org"