Re: [uml-user] uml upload speed capped at 46KB/s

[Riccardo M. <ric...@gm...>]

Hello,

On Sat, Jun 25, 2011 at 15:28, Manfred Haertel
<Man...@rz...> wrote:
> The slirp utility defers the TCP ACK for 200 milliseconds (which may be a
> good idea on a slow modem connection, but not in an UML environment).
>
> This limits the throughput to something around 9000 bytes (the TCP window
> size) in 0.2 seconds, leading to something around 45 or 46 kBytes per
> second.
>
> The solution is a very small patch to slirp to send out the ACK immediatly.
> Now I have also full speed when sending data from the UML guest to the host!
> :-)
>

Debian has merged this patch into their slirp package starting from
version 1.0.17-6.  So the `slirp-fullbolt` command on wheezy will soon
implement a real full-bolt :-)

See: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=658359

Thanks for the patch!

Riccardo