From owner-freebsd-hackers  Wed Jul  7 18:38: 0 1999
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Date: Wed, 7 Jul 1999 18:37:35 -0700 (PDT)
From: Matthew Dillon <dillon@apollo.backplane.com>
Message-Id: <199907080137.SAA95818@apollo.backplane.com>
To: Greg Lehey <grog@lemis.com>
Cc: Peter Jeremy <jeremyp@gsmx07.alcatel.com.au>,
	freebsd-current@FreeBSD.ORG, freebsd-hackers@FreeBSD.ORG
Subject: Re: Bursting at the seams (was: Heh heh, humorous lockup)
References: <99Jul8.090830est.40363@border.alcanet.com.au> <19990708110446.P2340@freebie.lemis.com>
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:Why not put the kernel in a different address space?  IIRC there's no
:absolute requirement for the kernel and userland to be in the same
:address space, and that way we would have 4 GB for each.
:
:Greg

    No, the syscall overhead is way too high if we have to mess with MMU
    context.  This would work fine on certain cpus with hardware PID support,
    such as the MIPS, but the entire TLB is wiped when you change the mmu 
    context on an Intel cpu.

					-Matt
					Matthew Dillon 
					<dillon@backplane.com>


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