From owner-freebsd-questions@FreeBSD.ORG Tue Jan 12 17:46:51 2010 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 87AF310656A3 for ; Tue, 12 Jan 2010 17:46:51 +0000 (UTC) (envelope-from cswiger@mac.com) Received: from asmtpout029.mac.com (asmtpout029.mac.com [17.148.16.104]) by mx1.freebsd.org (Postfix) with ESMTP id 746E88FC2B for ; Tue, 12 Jan 2010 17:46:51 +0000 (UTC) MIME-version: 1.0 Content-transfer-encoding: 7BIT Content-type: text/plain; charset=us-ascii Received: from cswiger1.apple.com ([17.227.140.124]) by asmtp029.mac.com (Sun Java(tm) System Messaging Server 6.3-8.01 (built Dec 16 2008; 32bit)) with ESMTPSA id <0KW5006KHAQ18460@asmtp029.mac.com> for freebsd-questions@freebsd.org; Tue, 12 Jan 2010 09:46:51 -0800 (PST) From: Chuck Swiger In-reply-to: <20100112141726.GA23278@mech-cluster241.men.bris.ac.uk> Date: Tue, 12 Jan 2010 09:46:49 -0800 Message-id: <11F836C5-7E9F-4ACC-948F-196EF605F1AB@mac.com> References: <20100112141726.GA23278@mech-cluster241.men.bris.ac.uk> To: Anton Shterenlikht X-Mailer: Apple Mail (2.1077) Cc: freebsd-questions@freebsd.org Subject: Re: top/ps: is Active Memory = sum(resident set size)? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 12 Jan 2010 17:46:51 -0000 Hi-- On Jan 12, 2010, at 6:17 AM, Anton Shterenlikht wrote: > Should the Active memory, as reported by top(1), be equal to the > sum of rss (the real memory (resident set) size of the process) > of all processes, as reported by ps(1)? No. They aren't measuring the same thing; in a system with plenty of available RAM, processes might be entirely resident because there is no memory pressure to start paging inactive pages out, but only be using a fraction of their address space, in which case active per top will be less than the sum of RSS. -- -Chuck