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Date: Mon, 2 May 2005 18:12:44 -0500 (CDT)
From: Mike Silbersack <silby@silby.com>
To: Bruce M Simpson <bms@spc.org>
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cc: Gleb Smirnoff <glebius@FreeBSD.org>
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cc: jmg@FreeBSD.org
cc: Sten Spans <sten@blinkenlights.nl>
Subject: Re: if_tap unaligned access problem
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On Thu, 28 Apr 2005, Bruce M Simpson wrote:

> jmg's suggestion of bringing in the NetBSD patches to allow the entire
> network stack to be compiled with unaligned accesses (for those platforms
> which support it) is interesting because it can simplify or eliminate
> some of the acrobatics needed in network drivers to deal with the mbuf
> alignment.

I'm too lazy to benchmark, but I suspect that having the ethernet code 
shift the packet backwards by two bytes after it strips off the ethernet 
header is going to be faster than requiring ip_input to allocate a new 
mbuf for each received packet.

Such a change would also ensure that we don't break all the other 
protocols that jmg didn't touch in his patch.

Mike "Silby" Silbersack