From owner-freebsd-questions@FreeBSD.ORG Wed Feb 9 01:34:48 2005 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 E9B3B16A4CE for ; Wed, 9 Feb 2005 01:34:47 +0000 (GMT) Received: from pi.codefab.com (pi.codefab.com [199.103.21.227]) by mx1.FreeBSD.org (Postfix) with ESMTP id A6BD643D2F for ; Wed, 9 Feb 2005 01:34:47 +0000 (GMT) (envelope-from cswiger@mac.com) Received: from localhost (localhost [127.0.0.1]) by pi.codefab.com (Postfix) with ESMTP id E1A825EAE; Tue, 8 Feb 2005 20:34:46 -0500 (EST) Received: from pi.codefab.com ([127.0.0.1]) by localhost (pi.codefab.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 30984-03; Tue, 8 Feb 2005 20:34:46 -0500 (EST) Received: from [192.168.1.3] (pool-68-161-50-112.ny325.east.verizon.net [68.161.50.112]) by pi.codefab.com (Postfix) with ESMTP id B5B695E47; Tue, 8 Feb 2005 20:34:44 -0500 (EST) Message-ID: <420968B2.4090208@mac.com> Date: Tue, 08 Feb 2005 20:34:42 -0500 From: Chuck Swiger Organization: The Courts of Chaos User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.5) Gecko/20041217 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Erik Trulsson References: <810a540e050208133310333144@mail.gmail.com> <20050208213612.GA29063@falcon.midgard.homeip.net> <810a540e050208134479b4e774@mail.gmail.com> <20050208222759.GA29360@falcon.midgard.homeip.net> <4209435E.5080302@mac.com> <20050209000919.GA56002@falcon.midgard.homeip.net> In-Reply-To: <20050209000919.GA56002@falcon.midgard.homeip.net> X-Enigmail-Version: 0.90.0.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: amavisd-new at codefab.com cc: freebsd-questions@freebsd.org Subject: Re: Inactive memory 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: Wed, 09 Feb 2005 01:34:48 -0000 Erik Trulsson wrote: > On Tue, Feb 08, 2005 at 05:55:26PM -0500, Chuck Swiger wrote: >>Wired memory is typically the kernel text (executable code), any kernel >>modules which have been loaded, and dynamic kernel memory used for critical >>structures like the process table, descriptor table, VM page tables, which >>tend to be staticly allocated. The pager never touches these, they are >>always resident in RAM. > > Considering that the amount of memory in the "Wired" state tends to > vary quite a bit as the system runs it is certainly not all statically > allocated. Sure, wired memory isn't fixed in size, it changes in response to load and to loading or unloading kernel modules. It used to be the case that many kernel structures were fixed in size, they are become more flexible and more self-tuning over time as people improve things. [ ... ] >>More dynamic kernel data structures like the I/O buffer used for disk >>access, network buffers, and the like are also wired down, but the system >>will adjust the size and flush pages of data from open files and the like >>to disk depending on the situation. That pool of memory is the Cached >>category. > > No, that is not Cached memory. It might be "Buffered", but I am not > sure exactly what goes in that category (it is however the only > category whose size do not fluctuate as time passes.) I could be wrong, too, I suppose. :-) One of the problems is that people use certain terms to talk about different types of memory, and it doesn't do you much good if your understanding of terms doesn't match what the code is actually doing. -- -Chuck