Tuning needed for slow RDP FreeBSD 9 -> Win 2008 R2

[Peter Olsson]

On Mon, Feb 13, 2012 at 04:09:05PM +0100, Ivan Voras wrote:
> On 13/02/2012 02:50, Peter Olsson wrote:
> > Desktop: FreeBSD 9.0-RELEASE amd64, generic kernel,
> > running Openbox. My WAN is about 1.2 Mbps, and I try
> > to run RDP to windows servers beyond my WAN.
> > 
> > RDP to a Windows Server 2003 SP2 is fast and works
> > without problems.
> > 
> > RDP to a Windows Server 2008 R2 is very slow,
> > and sometimes just disconnects.
> > 
> > I tried changing a couple of net.inet.tcp sysctl:
> 
> > Nothing has helped, do you have any ideas what I
> > should tune?
> 
> It is highly unlikely that any network tuning will help here - this is
> almost certainly an application-level problem.
>
> For what it's worth, I'm using rdesktop to a Win2k8 R2 server without
> any lag other problems.

I have a colleague who runs Crunchbang (ie Debian) desktop.
He had exactly the same performance problem until he used
these sysctl:
net.core.rmem_max=1048576
net.core.rmem_default=1048576
net.core.wmem_max=1048576
net.core.wmem_default=1048576
net.ipv4.tcp_rmem=1048576 1048576 3444736
net.ipv4.tcp_wmem=1048576 1048576 3444736

I don't know where he got those values, or what they could
be translated to in FreeBSD, but they did solve the problem
for him. That's why I'm hoping to find a similar sysctl
solution for FreeBSD.

I did sysctl -a | grep mem and grep buf, but find nothing
obvious, except the net.inet.tcp.recvbuf and sendbuf values
I have already tried changing.

Also, I run Win7 in Virtualbox in my desktop, and from that
Win7 I don't have the performance problem towards that RDP
server.

-- 
Peter Olsson                    pol at leissner.se