Linux Router: TCP slow, UDP fast

Mikael Abrahamsson swmike at
Sat Feb 14 13:09:33 UTC 2009

On Sat, 14 Feb 2009, Lee wrote:

> Try enabling window scaling
>  echo 1 > /proc/sys/net/ipv4/tcp_window_scaling
> or, if you really want it disabled, configure a larger minimum window size
>  net.ipv4.tcp_rmem = 64240 87380 16777216

Without window scaling, you're limited to 64k window size anyway.

Chris, what is the round trip delay between the machines involved in your 
TCP session?

Mikael Abrahamsson    email: swmike at

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