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Date: Tue, 25 Apr 2006 10:22:54 +0900
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From: gnn@freebsd.org
To: Kirk McKusick <mckusick@chez.mckusick.com>
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Cc: arch@freebsd.org
Subject: Re: Linus Torvalds on FreeBSD's Use of Copy-on-write
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At Sun, 23 Apr 2006 23:33:30 -0700,
Kirk McKusick wrote:
> 
> Anyone working on zero-copy sockets care to respond to this?
> 
>     http://developers.slashdot.org/developers/06/04/21/1536213.shtml
> 
> Linus Torvalds made reference to some possible future extensions.
> This included vmsplice(), a system call since implemented by Jens
> Axboe "to basically do a 'write to the buffer', but using the
> reference counting and VM traversal to actually fill the buffer."
> Reviewing the implications of using such a system call lead to a
> comparison with FreeBSD's ZERO_COPY_SOCKET which uses COW (copy on
> write).
> 

To be honest, what all this has made me think of is that we should
have a "big board" of unsolved problems we'd like to look at.  This
certainly deserves a place, as it's an interesting question.  As
scientists and engineers we should be interested in such things, even
if the original statement was poorly worded.

Perhaps on a FreeBSD Feature Wiki?  We could even propose a benchmark
as a SoC project.

Later,
George