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To: Julian Elischer <julian@elischer.org>
References: <43D05151.5070409@elischer.org>
	<200601231616.49140.jhb@freebsd.org> <43D55739.80608@elischer.org>
From: des@des.no (=?iso-8859-1?q?Dag-Erling_Sm=F8rgrav?=)
Date: Mon, 23 Jan 2006 23:35:42 +0100
In-Reply-To: <43D55739.80608@elischer.org> (Julian Elischer's message of
	"Mon, 23 Jan 2006 14:22:49 -0800")
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Cc: freebsd-current@freebsd.org
Subject: Re: kernel thread as real threads..
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Julian Elischer <julian@elischer.org> writes:
> However I would like to suggest that we change the way that aio
> works..
>
> My suggestion is that when a process does AIO, that we "fork a
> ksegroup" and attach it to the process, and assign it a (or some)
> worker thread to do the aio work.  The userland process would be
> oblivious of the extra (kernel) threads in that kseg and they would
> be independently schedulable.  They would however automatically have
> full access to the correct address space.

Agreed.  This would actually greatly simplify the aio code (getting
rid of all the vm monkeying), and reduce the likelihood of future
security or stability issues with it.

DES
--=20
Dag-Erling Sm=F8rgrav - des@des.no