Gus Wirth wrote: > James G. Sack (jim) wrote: >> Gus Wirth wrote: >>> James G. Sack (jim) wrote: >>> [snip] >>>> It was my understanding that GigE automatically adjusted itself so that >>>> crossover cables have no impact, and are never needed. >>> Empirical testing shows that it works. I directly connected my laptop to >>> the server with a regular ethernet cable and I can transfer files just >>> fine. I can also up the MTU on both machines and everything still works >>> fine. It still doesn't transfer any faster than 100Mb/s ethernet >>> however. Now it's time to start playing with transmit queue lengths. And >>> to take the switch back. Bargin price switches don't seem to be worth >>> it. >>> >> >> Well, mtu-1500 _is_ pretty much a hardware standard, isn't it. I would >> expect that support for jumbo frames might command a hefty premium >> >> -- awaiting comment from net-hw experts > > I found some info at this site: > <http://www.enterprisenetworkingplanet.com/nethub/article.php/3485486> > and tried the suggestions, but nothing seems to help. I did some more > tests including with ttcp and did transfers between my mythtv box, > laptop and server all in various combinations. I got up to 18MB/s file > transfers between the laptop and the mythtv box. It seems that my server > is just slow. My mythtv box is the fastest of the three, it has a > Sempron 2600 on a ECS 755-A2 motherboard and I put in a gigabit ethernet > card with a Realtek 8169 chip. >
I think you should see differences depending on the direction, too. I believe it usually ends up being limited by the receiver capabilities, although I suppose you could cook up counter-examples. ..jim -- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
