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Date: Thu, 29 Jan 2004 10:00:10 -0500 (EST)
From: Robert Watson <rwatson@freebsd.org>
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To: Julian Elischer <julian@elischer.org>
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cc: Unix Shepherd <unixshepherd@wanadoo.fr>
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Subject: Re: kernel threads
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On Wed, 28 Jan 2004, Julian Elischer wrote:

> the KSE stuff requires too much assistance from teh Userland Thread
> scheduler. 
> 
> HOWEVER it is possible that kthreads may one day be implemented as
> multiple threads of a single kernel process..  (but not yet) 

John has been talking about doing this for a while -- clustering the
kernel threads into a smaller number of kernel processes or a single
kernel process.  This is the approach Darwin takes as well, FWIW -- they
have a kernel_task in which all the various kernel threads hang out, which
avoids the overhead of full processes, as well as the emotional baggage. 
I think I saw John put it on his TODO list in Perforce, so maybe it's
coming soon :-). 

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert@fledge.watson.org      Senior Research Scientist, McAfee Research