From owner-freebsd-hackers Wed Jan 13 15:47:07 1999 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id PAA21949 for freebsd-hackers-outgoing; Wed, 13 Jan 1999 15:47:07 -0800 (PST) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from alcanet.com.au (border.alcanet.com.au [203.62.196.10]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id PAA21944 for ; Wed, 13 Jan 1999 15:47:04 -0800 (PST) (envelope-from peter.jeremy@auss2.alcatel.com.au) Received: by border.alcanet.com.au id <40358>; Thu, 14 Jan 1999 10:45:10 +1100 Date: Thu, 14 Jan 1999 10:45:41 +1100 From: Peter Jeremy Subject: Re: Problems with 3.0 To: hackers@FreeBSD.ORG Cc: tlambert@primenet.com Message-Id: <99Jan14.104510est.40358@border.alcanet.com.au> Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Tue, 12 Jan 1999 22:18:07 +0000 (GMT), Terry Lambert wrote: >Another one recently discovered is that it *appears* that you can >map (read only) the same file twice letting the system decide where >to put it (pass NULL as binding location), and the second time the >system will return the same address as the first time, instead of >doing the right thing and setting up the mapping at a different >location. Why is this behaviour wrong? Given that both mappings are read-only and you haven't said that you want it mapped at a specific location, why shouldn't the system just reuse the pre-existing mapping? This is definitely easier for the kernel, and reduces system resource requirements (page table entries and suchlike). Peter -- Peter Jeremy (VK2PJ) peter.jeremy@alcatel.com.au Alcatel Australia Limited 41 Mandible St Phone: +61 2 9690 5019 ALEXANDRIA NSW 2015 Fax: +61 2 9690 5982 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message