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Subject: RE: big picture UDP/IP performance question re 2.6.18  -> 2.6.32
Date: Tue, 4 Oct 2011 15:54:50 -0400
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From: "Loke, Chetan" <Chetan.Loke@netscout.com>
To: <starlight@binnacle.cx>, "Eric Dumazet" <eric.dumazet@gmail.com>
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        "Willy Tarreau" <w@1wt.eu>, "Peter Zijlstra" <a.p.zijlstra@chello.nl>
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> Sometimes I think it might be nice to run without
> an OS at all :-)
> 
> We are looking at various kernel bypass approaches
> for receiving packets and it's in my mind that
> one of these may get us to running on newer
> kernels without giving up performance.
> 

If permissible in your environment, try running PACKET:tpacket_v3.

Also, I always wondered about the following in the output of:

net/ptype
dada          edsa_rcv+0x0/0x246
001b          dsa_rcv+0x0/0x225

and so when I'm fine tuning apps in virtual environments I nuke the
above during kernel compilation.


Chetan Loke