On Tue, Aug 22, 2000 at 11:15:47AM -0500, Mark_H_Johnson@Raytheon.com wrote: > As part of a study for NASA, we ran "netpipe" on both single channel and > two channel bonded Ethernet networks and got some odd results. > - The single channel results looked OK. > - The channel bonded results had some serious performance drops. > I was not able to find a documented problem about this. Is this a known > problem [with a work around?] or if new, what kind of information will be > needed to help isolate it? I've included some sample data about our > configuration and the symptoms below. I will gladly send raw data & more > detailed configuration information if that will help. Please respond to me > directly - I don't subscribe to linux-net & linux-kernel-digest was still > down the last time I've checked. Thanks. The performance drops are probably caused by packet reordering. Extensive packet reordering causes TCP to detect congestion and causes extensive retransmits and lower congestion windows. Linux 2.4.0test7-preLATEST has some sender side improvements to handle reordering in the network better (and some receiver side hacks that may or more likely may not work) The best solution is to avoid reordering by not sending more than a single stream / interface. -Andi - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
