From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nivedita Singhvi <niv@us.ibm.com>
Subject: Re: MPI benchmark performance gap between native linux
	anddomU
Date: Tue, 05 Apr 2005 15:53:19 -0700
Message-ID: <425316DF.3090009@us.ibm.com>
References: <6C21311CEE34E049B74CC0EF339464B902FB1D@cacexc12.americas.cpqcorp.net>
	<4253125E.4060209@cs.uchicago.edu>
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To: xuehai zhang <hai@cs.uchicago.edu>
Cc: Xen-devel@lists.xensource.com, "Santos,
	Jose Renato G (Jose Renato Santos)" <joserenato.santos@hp.com>
List-Id: xen-devel@lists.xenproject.org

xuehai zhang wrote:


>>> echo -2 > /proc/sys/net/ipv4/tcp_adv_win_scale
> 
> 
> In my experiments, I notice the above changing doesn't persist upon 
> reboots (every reboot will change the value back to 2, the default value 
> for Debian Sarge 3.1). Is there a way to make a permanent changing?


You can edit /etc/sysctl.conf and add the following entry:

net.ipv4.tcp_adv_win_scale = -2

Or you can put in a sysctl -w net.ipv4.tcp_adv_win_scale -2
into some appropriate /etc/init.d startup script.

thanks,
Nivedita