From owner-freebsd-questions@FreeBSD.ORG Tue Nov 16 16:15:36 2004 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 50D4E16A4CE for ; Tue, 16 Nov 2004 16:15:36 +0000 (GMT) Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101]) by mx1.FreeBSD.org (Postfix) with ESMTP id C0DA443D49 for ; Tue, 16 Nov 2004 16:15:35 +0000 (GMT) (envelope-from dan@dan.emsphone.com) Received: (from dan@localhost) by dan.emsphone.com (8.13.1/8.13.1) id iAGGEBKg009897; Tue, 16 Nov 2004 10:14:11 -0600 (CST) (envelope-from dan) Date: Tue, 16 Nov 2004 10:14:11 -0600 From: Dan Nelson To: Jonathon McKitrick Message-ID: <20041116161411.GE80412@dan.emsphone.com> References: <20041116160851.GB50871@dogma.freebsd-uk.eu.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20041116160851.GB50871@dogma.freebsd-uk.eu.org> X-OS: FreeBSD 5.3-STABLE X-message-flag: Outlook Error User-Agent: Mutt/1.5.6i cc: freebsd-questions@freebsd.org Subject: Re: Question about page faults and swap space X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 16 Nov 2004 16:15:36 -0000 In the last episode (Nov 16), Jonathon McKitrick said: > This is probably a dumb question, but it's been a long time since my > OS theory classes. ;-) > > How can I get a page fault if swap space is never used? Why would > anything be swapped out and yet not appear as usage on the swap > partition, since that never goes away once used? Accesses to executable images or mmaped files will cause page faults. They'll show up as vnode pageins as opposed to swap pageins in "vmstat -s" or "systat -v". -- Dan Nelson dnelson@allantgroup.com