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Re: The next broadband killer: advanced operating systems?

  • From: Leo Bicknell
  • Date: Mon Oct 22 14:36:20 2007

In a message written on Mon, Oct 22, 2007 at 06:42:48PM +0200, Mikael Abrahamsson wrote:
> You can achieve the same thing by running a utility such as TCP Optimizer.
> Turn on window scaling and increase the TCP window size to 1 meg or so, 
> and you should be good to go.

A bit of a warning, this is not exactly the same thing.  When using
the method listed above the system may buffer up to 1 Meg for each
active TCP connection.  Have 50 people connect to your web server
via dialup and the kernel may eat up 50 Meg of memory trying to
serve them.  That's why the OS defaults have been so low for so

The auto-tuning method I referenced dynamically changes the size
of the window based on the free memory and the speed of the client
allowing an individual client to get as big as it needs while
insuring fairness.

On a single user system with a single TCP connection they both do the
same thing.  On a very busy web server the first may make it fall over,
the second should not.


       Leo Bicknell - [email protected] - CCIE 3440
        PGP keys at
Read TMBG List - [email protected],

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