[129761] in North American Network Operators' Group
Re: Troubleshooting TCP performance tutorial
daemon@ATHENA.MIT.EDU (Kevin Oberman)
Sat Sep 18 01:38:00 2010
To: "Abel Alejandro" <aalejandro@worldnetpr.com>
In-reply-to: Your message of "Fri, 17 Sep 2010 20:06:09 EDT."
<79BBBA445314D14C927525E537E603631F7B92@wnetexchg01.worldnetpr.com>
Date: Fri, 17 Sep 2010 22:37:46 -0700
From: "Kevin Oberman" <oberman@es.net>
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
> Date: Fri, 17 Sep 2010 20:06:09 -0400
> From: "Abel Alejandro" <aalejandro@worldnetpr.com>
>
> Greetings,
>
> This past week I have been trying to find the root cause of tcp
> performance problems of a few clients that are using a third party metro
> Ethernet for transport. RFC2544 tests (Layer 2) and iperf using UDP give
> good symmetric performance almost 100% the speed of the circuit. However
> all kind of TCP tests result in some kind of asymmetrical deficiency,
> either the upstream or downstream of the client is hugely different. The
> latency is not a huge factor since all the metro Ethernet connections
> have less than 2 ms.
>
> So the question basically if is there a good tutorial or white paper for
> troubleshooting tcp with emphasis of using tools like Wireshark to debug
> and track this kind of problems.
>
> Regards,
> Abel.
You might look at http://fasterdata.es.net. A lot of it is aimed at very
large volume data transfers, but quite a bit is relevant to all TCP
issues.
--
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman@es.net Phone: +1 510 486-8634
Key fingerprint:059B 2DDF 031C 9BA3 14A4 EADA 927D EBB3 987B 3751
