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Message-ID: <3C75E905.9000809@candelatech.com>
Date: Thu, 21 Feb 2002 23:45:25 -0700
From: Ben Greear <greearb@candelatech.com>
Organization: Candela Technologies
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To: "David S. Miller" <davem@redhat.com>
CC: dank@kegel.com, linux-kernel@vger.kernel.org, zab@zabbo.net
Subject: Re: is CONFIG_PACKET_MMAP always a win?
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David S. Miller wrote:

>    From: Dan Kegel <dank@kegel.com>
>    Date: Thu, 21 Feb 2002 17:51:20 -0800
> 
>    What's the best way to retrieve raw packets from the kernel?
>    
>    a) use libpcap
>  ...   
>    b) use af_packet
>  ...   
>    c) enable CONFIG_PACKET_MMAP, use PACKET_RX_RING
>    
>    If I understand it right, b costs one memcpy and one recv, and c costs
>    two memcpys.  Which one wins?
> 
> "a" should be doing "c" when it is available in the kernel.
> If not, get a newer copy of the libpcap sources, preferably
> from Alexey's site:
> 
> ftp.inr.ac.ru:/ip-routing/


And if you can figure out how to do c, and feel like
sharing, please do let me know!  Documentation is a
bit sparse..at least wherever I've been looking.

Enjoy,
Ben



-- 
Ben Greear <greearb@candelatech.com>       <Ben_Greear AT excite.com>
President of Candela Technologies Inc      http://www.candelatech.com
ScryMUD:  http://scry.wanfear.com     http://scry.wanfear.com/~greear


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