Help with RWIN settings in Fedora Core3

[Critofer 0]

I just recently starting working with Linux again. So I'm a little rusty.

I'm trying to increase the RWIN value for my broadband connection. 5000down 768up cable

According to the TCP analyzer at speedguide.net

my default receive window is at 5840, in windowsXp it is at

64240. In windows I used DrTCP I downloaded from DSLReports.

I need to know how to change it in Fedora Core 3.

System specs

MSI Neo2 PE mother board

Intel 2.8E prescott processor.

Realtec on board Lan.

Geforce 6800 gt graphics

Maxtor 200GB SATA 7200 rpm (No Raid)

 

[BSchindler 0]

This is a good question. Windows machines were never optimized for high speed connections. The tweaks you use for their op syses are useful. However, you will find linux has always been better optimized for high speed and performance.

 

You did not state which version of Linux you were running. However, you may want to look at the following:

 

cat /proc/sys/net/ipv4/tcp_timestamps

cat /proc/sys/net/ipv4/tcp_window_scaling

cat /proc/sys/net/ipv4/tcp_sack

 

You will probably see the number one "1" returned for each of them. If so, all is good. If any of the values returned is zero you can change them with the following command(s):

 

** NOTE, YOU MUST BE ROOT TO DO THIS !!

 

echo 1 /proc/sys/net/ipv4/tcp_timestamps

 

etc.

 

The buffers allocated are based on a lot of factors. Altering the sizes without understanding what the impact is is clearly NOT ADVISED. You can easily make the overall performance of your machine very poor. You may, however, want to look at these:

 

cat /proc/sys/net/core/rmem_default - default rx window

cat /proc/sys/net/core/rmem_max - maximum rx window

cat /proc/sys/net/core/wmem_default - default tx window

cat /proc/sys/net/core/wmem_max - maximum tx window

 

These parameters may be altered as well. But, I DO NOT ADVISE YOU DO THIS. At least until you have a very good reason to do so. By in large, you will find Linux machines' configurations well balanced for performance.

 

As you mention you are just getting "back to Linux" you may want to read up a bit on network configuration. Do a Google search on "Linux TCP/IP Settings" or "Linux Network Settings" etc..

 

Have fun with Linux,

Bill

 

 

 

[martouf 0]

Quote:

echo 1 /proc/sys/net/ipv4/tcp_timestamps

correct syntax being the very essence of success, it should properly be:

[size:4][tt]echo 1 > /proc/sys/net/ipv4/tcp_timestamps[/tt][/color]

(must redirect '>' the output of 'echo' to the above named file)

cheers!