On Sat, 10 Mar 2007, Jeff Bromberger wrote:
> Scott Radvan wrote:
> > On Fri, 09 Mar 2007 16:57:37 -0600
> > Jeff Bromberger <[EMAIL PROTECTED]> wrote:
> >
> >
> > > Hello,
> > >
> > > I have listed my dmesg and ifconfig at the end of this post for reference.
> > > The problem I'm having is that any ftp or lynx traffic
> > > to an external (ie. outside of my LAN) host comes in at 200KB/sec.
> > > Meanwhile, my Windows boxes which are on the same switch, router and cable
> > > modem, can pull down from the net at over 800KB/sec. I have swapped
> > > cables, tried different ports on the switch and done every
> > > other type of A/B test to no avail. I have also tried both physical
> > > nics on the off chance that I had a hardware issue with one of them.
> > > When I transfer between the OpenBSD machine and an XP machine over
> > > the gigabit ethernet (again using ftp) I get 7500KB/sec. That's
> > > obviously a lot better, but when I transfer between two XP machines
> > > (again with ftp) I get 17000KB/sec.
> > >
> > > But here's where it gets really weird (to me at least). I can run 3
> > > ftp or lynx sessions at the same time and get 200KB/sec on each of
> > > them. So obviously the NIC, router, cable modem, etc. are capable of
> > > the total throughput that I'm after, but I can't seem to get it in
> > > any one connection. The throughput is always so close to 200KB/sec
> > > regardless of the client, server, server load, etc. that I can't help
> > > but think that there's some kind of throttling limitation in effect
> > > here. Of course the fact that the local LAN traffic is not limited
> > > to this rate blows that theory, unless the limitation is actually
> > > based on the media type (100MBit vs. 1000MBit). I'm pretty much out
> > > of ideas!
> > >
> > > Any thoughts?
> > >
> > >
> >
> >
> > You might like to check your net.inet.tcp.recvspace and
> > net.inet.tcp.sendspace sysctl settings, as mentioned here in the FAQ,
> > Section 6.6.4.
> >
> > http://www.openbsd.org/faq/faq6.html#Tuning
> >
> > I saw a similar problem on my ADSL2+ line, until changing these
> > particular parameters. With any luck, it will allow you to make full
> > use of your connection speed and resolve the issues you are having.
> >
> >
> >
> Wow, what a difference. THANK YOU so much. I'm now getting 700KB/sec instead
> of 200KB/sec. That's with those parameters set to 131072 instead of 16384 the
> default. I tried 256k and it didn't see to improve any more so I backed it
> back down.
>
> Thanks again!
> Jeff
I'm seeing this also, The thing to watch for is high latency on a high
bandwitdh line. When I switched provider, I was seeing lower
throughput than my previous line, which actually had lower bandwitdh.
My old line had a ping time to the first router of about 7ms, my
current line has a ping time of 23ms to the first router. That sucks a
bit for interactive work, bur it's cheap, and with the increased
buffer size I get 15Mbit/s.
-Otto
