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Date: Thu, 2 Jan 2003 17:01:07 -0800
From: Larry McVoy <lm@bitmover.com>
To: Thomas Ogrisegg <tom@rhadamanthys.org>
Cc: "David S. Miller" <davem@redhat.com>, linux-kernel@vger.kernel.org,
       lm@bitmover.com
Subject: Re: [PATCH] TCP Zero Copy for mmapped files
Message-ID: <20030103010107.GB6416@work.bitmover.com>
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> It might be a bit difficult to convert all applications to
> sendfile. Especially those for which you don't have the
> source code.

And the list of applications which do

	sock = socket(...);
	map = mmap(...);
	write(sock, map, bytes);

are?  There are not very many that I know of and if you look carefully
at the bandwidth graphs in LMbench you'll see why.  There is a cross
over point where mmap becomes cheaper but it used to be around 16-64K.
I don't know what it is now, I doubt it's moved much.  I can check if
you really want.
-- 
---
Larry McVoy            	 lm at bitmover.com           http://www.bitmover.com/lm 
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