From owner-freebsd-stable Thu Jul 26 9:35:11 2001 Delivered-To: freebsd-stable@freebsd.org Received: from rover.village.org (rover.bsdimp.com [204.144.255.66]) by hub.freebsd.org (Postfix) with ESMTP id 4DB8337B403 for ; Thu, 26 Jul 2001 09:35:08 -0700 (PDT) (envelope-from imp@harmony.village.org) Received: from harmony.village.org (harmony.village.org [10.0.0.6]) by rover.village.org (8.11.3/8.11.3) with ESMTP id f6QGYvF65604; Thu, 26 Jul 2001 10:35:02 -0600 (MDT) (envelope-from imp@harmony.village.org) Received: from harmony.village.org (localhost.village.org [127.0.0.1]) by harmony.village.org (8.11.3/8.11.4) with ESMTP id f6QGYpw04451; Thu, 26 Jul 2001 10:34:53 -0600 (MDT) (envelope-from imp@harmony.village.org) Message-Id: <200107261634.f6QGYpw04451@harmony.village.org> To: janb@cs.utep.edu Subject: Re: FreeBSD 4.3 and 6G RAM Cc: Stefan Molnar , Marek Gorka , freebsd-stable@FreeBSD.ORG In-reply-to: Your message of "Wed, 18 Jul 2001 10:45:07 MDT." References: Date: Thu, 26 Jul 2001 10:34:51 -0600 From: Warner Losh Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG In message janb@cs.utep.edu writes: : I am interestied as to why this is. Is there a sound technical reason do : not support this, or was it merely the fact that there are not too many : machines that can take advantage of this anyway, and nobody got around to : do this? Four reasons: 1) Lazy device driver writers who don't use bus_space_dma routines. 2) Lazy bus_space_dma author who didn't provide for a good way to do network things. 3) No support in the pmap for the 39 bit addresses 4) The perception that PAE will cost more than it gains you. Warner To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message