On Wed, Jan 14, 2009 at 10:28:59PM -0500, Daniel Ouellet wrote: > Jason Dixon wrote: >> I have a Verizon USB720 dongle that shows up as ucom0. I intend to use >> it for connecting remotely with my X40. I'm having problems when >> packets exceed a certain size. When this happens, the return packets >> never make it back to my system. >> >> I can connect fine with ppp(8). I can ping remote hosts and do >> traceroutes. I can ssh to hosts and perform basic commands. Only when >> the payload exceeds ~900 bytes do things start to fail. This happens >> with almost all TCP traffic, but is most noticeable with SSH or HTTP. > > Many experience problem with the send/received window of the tcp packets > and can only get decent transfer speed when increase form the default to > 65k. > > # sysctl | grep space > net.inet.tcp.recvspace=16384 > net.inet.tcp.sendspace=16384 > net.inet.udp.recvspace=41600 > net.inet.udp.sendspace=9216 > > try using it at 65536. > > sysctl net.inet.tcp.recvspace=65536 > sysctl net.inet.tcp.sendspace=65536 > > It may help you some, but if not, it's never the less real quick to test > and see if in your case it would help or not. > > It may not help your MTU size limitation, but it sure should help your > performance however.
Unfortunately, neither these nor setting the mtu/mru has any effect. -- Jason Dixon DixonGroup Consulting http://www.dixongroup.net/
