[111851] in North American Network Operators' Group
Re: Linux Router: TCP slow, UDP fast
daemon@ATHENA.MIT.EDU (Florian Weimer)
Sat Feb 14 07:55:11 2009
From: Florian Weimer <fw@deneb.enyo.de>
To: Chris <chris@ghostbusters.co.uk>
Date: Sat, 14 Feb 2009 13:55:02 +0100
In-Reply-To: <2f77000a0902140425n628d53b8xbdabe8b8fb265fe4@mail.gmail.com>
(chris@ghostbusters.co.uk's message of "Sat, 14 Feb 2009 12:25:23
+0000")
Cc: nanog list <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
> I'm losing the will to live with this networking headache ! Please feel free
> to point me at a Linux list if NANOG isn't suitable. I'm at a loss where
> else to ask.
The linux-net might be more appropriate indeed.
> With and without shaping and over different bandwidth providers using the
> e1000 driver for an Intel PRO/1000 MT Dual Port Gbps NIC (82546EB) I can
> replicate full, expected throughput with UDP but consistently only get
> 300kbps - 600kbps throughput _per connection_ for outbound TCP
I've seen this behavior as the result of duplex mismatches.
(The tcp settings are end system matters and do not affect how the
router forwards traffic.)
