From owner-freebsd-questions@FreeBSD.ORG Mon Feb 12 15:17:26 2007 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 4973116A400 for ; Mon, 12 Feb 2007 15:17:26 +0000 (UTC) (envelope-from freebsd-questions-local@be-well.ilk.org) Received: from mail3.sea5.speakeasy.net (mail3.sea5.speakeasy.net [69.17.117.5]) by mx1.freebsd.org (Postfix) with ESMTP id 2701513C461 for ; Mon, 12 Feb 2007 15:17:26 +0000 (UTC) (envelope-from freebsd-questions-local@be-well.ilk.org) Received: (qmail 24627 invoked from network); 12 Feb 2007 15:17:25 -0000 Received: from dsl092-078-145.bos1.dsl.speakeasy.net (HELO be-well.ilk.org) ([66.92.78.145]) (envelope-sender ) by mail3.sea5.speakeasy.net (qmail-ldap-1.03) with SMTP for ; 12 Feb 2007 15:17:25 -0000 Received: by be-well.ilk.org (Postfix, from userid 1147) id CBF4328434; Mon, 12 Feb 2007 10:17:24 -0500 (EST) To: Cy Schubert References: <200702102231.l1AMVKNl007984@cwsys.cwsent.com> From: Lowell Gilbert Date: Mon, 12 Feb 2007 10:17:24 -0500 In-Reply-To: <200702102231.l1AMVKNl007984@cwsys.cwsent.com> (Cy Schubert's message of "Sat\, 10 Feb 2007 14\:31\:20 -0800") Message-ID: <44odnziewr.fsf@be-well.ilk.org> User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.0.93 (berkeley-unix) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: freebsd-questions@freebsd.org Subject: Re: Tuning Question 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: Mon, 12 Feb 2007 15:17:26 -0000 Cy Schubert writes: > I have a question about tuning FreeBSD systems, specifically in regard to > memory. At one time on Solaris systems it was recommended to keep scan rate > below 200 pages per second. (Today it's 300 pages per second, dependent on > the amount of memory, class of system.) Are there any recommendations or > rules of thumb a person can use to determine when a memory upgrade is > required? My machines are only busy during port builds when the scan rate > can vary greatly and the page out rate could reach as high as two pages per > second during brief periods. What kind of memory and paging metrics should > I use on FreeBSD systems? I'm not convinced that such a simple algorithm makes sense these days. If the system is normally pretty quiet, then it is unlikely you'll see any difference from optimizing memory behaviour further. I believe that when top(1) gives memory sizes, they are in bytes rather than pages as the manual indicates. -- Lowell Gilbert, embedded/networking software engineer, Boston area http://be-well.ilk.org/~lowell/