From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: 10GBE performance drop with net.ipv4.tcp_timestamps=0
Date: Tue, 19 Jun 2012 23:31:33 +0200
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Cc: Linux Netdev List <netdev@vger.kernel.org>
To: Stefan Priebe <s.priebe@profihost.ag>
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On Tue, 2012-06-19 at 23:08 +0200, Stefan Priebe wrote:
> Hello List,
> 
> i'm testing 10GBE speed with tweo servers. One with 3.5-rc3 nd thoe 
> other one whith RHEL 6 (2.6.32 kernel).
> 
> I noticed that setting
> net.ipv4.tcp_timestamps=0
> 
> descreased the performance from 9,7 Full Duplex to 3-4Gb/s.
> 
> Is this bahviour fine? What should / could i tet?
> 

Really, you should provide more input than that, if you really want us
to help.