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Date: Thu, 1 Dec 2005 15:59:26 +0200
From: Vlad GALU <vladgalu@gmail.com>
To: freebsd-hackers@freebsd.org
In-Reply-To: <438F00D8.4040302@spintech.ro>
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References: <438F00D8.4040302@spintech.ro>
Subject: Re: cwnd and sstresh monitor
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On 12/1/05, Alin-Adrian Anton <aanton@spintech.ro> wrote:
> Dear Hackers,
>
>         I would like to monitor the changes of cwnd and sstresh values du=
ring
> TCP traffic, in order to plot graphs and interpret congestion.
>
>         So I need (cwnd, timestamp) and (sstresh, timestamp) records to b=
e
> taken everytime one of the two variables is modified.
>
>         I'd like to ask you for suggestions, which would be the best apro=
ach
> (kernel patch, kernel module, etc?), and how would this be done best?
> (the interception of values, the storage of snapshots, etc)?
>

   Does exporting them via sysctl, and graph them using anything
(rrdtool) sound reasonable ?
--
If it's there, and you can see it, it's real.
If it's not there, and you can see it, it's virtual.
If it's there, and you can't see it, it's transparent.
If it's not there, and you can't see it, you erased it.