From owner-freebsd-questions@FreeBSD.ORG Thu Jun 14 07:55:14 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 E509016A41F for ; Thu, 14 Jun 2007 07:55:14 +0000 (UTC) (envelope-from youshi10@u.washington.edu) Received: from mxout3.cac.washington.edu (mxout3.cac.washington.edu [140.142.32.166]) by mx1.freebsd.org (Postfix) with ESMTP id C47DE13C447 for ; Thu, 14 Jun 2007 07:55:14 +0000 (UTC) (envelope-from youshi10@u.washington.edu) Received: from smtp.washington.edu (smtp.washington.edu [140.142.32.141] (may be forged)) by mxout3.cac.washington.edu (8.13.7+UW06.06/8.13.7+UW07.05) with ESMTP id l5E7tEha000680 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 14 Jun 2007 00:55:14 -0700 X-Auth-Received: from [192.168.10.45] (c-24-10-12-194.hsd1.ca.comcast.net [24.10.12.194]) (authenticated authid=youshi10) by smtp.washington.edu (8.13.7+UW06.06/8.13.7+UW07.03) with ESMTP id l5E7tDa8023438 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Thu, 14 Jun 2007 00:55:13 -0700 Message-ID: <4670F462.8020002@u.washington.edu> Date: Thu, 14 Jun 2007 00:55:14 -0700 From: Garrett Cooper User-Agent: Thunderbird 2.0.0.0 (Windows/20070326) MIME-Version: 1.0 To: cadastrosonline cadastrosonline References: <306715.62215.qm@web57310.mail.re1.yahoo.com> In-Reply-To: <306715.62215.qm@web57310.mail.re1.yahoo.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-PMX-Version: 5.3.1.294258, Antispam-Engine: 2.5.1.298604, Antispam-Data: 2007.6.14.3351 X-Uwash-Spam: Gauge=IIIIIII, Probability=7%, Report='LEO_OBFU_SUBJ_RE 0.1, __CT 0, __CTE 0, __CT_TEXT_PLAIN 0, __HAS_MSGID 0, __MIME_TEXT_ONLY 0, __MIME_VERSION 0, __SANE_MSGID 0, __USER_AGENT 0' Cc: freebsd-questions@freebsd.org Subject: Re: Memory mannagment 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: Thu, 14 Jun 2007 07:55:15 -0000 cadastrosonline cadastrosonline wrote: > First of all, > > > > "Each process has its own private address space. The address space is initially divided > into three logical segments: text, > data, and stack. " > > > > But if the address is just something like 343556 then how does it > really work? The memory is divided into segments is that what it means? > > > > "The data segment contains the initialized and uninitialized data portions of a program" > > > > Is it talking about multithreading? I COULDNT FIND anything talking > about how freebsd deals with multithreading, just found out it does it > by man pthread. > > > > Tell me anything else interesting to know about memory mannagment, does > it use any algorithm to substitute a page when out of pages in memory? > such as "second chance" "fifo" "lru" (last recently used) "nfu" (not > frequently used) and so on? I am studying freebsd but sometimes I am > out of ways to find out, yes I am reading the handbook about memory > mannagment as you can see my quotes but sometimes I don't understand. > > > > Thanks in advance. > This question is better suited for the hackers@ list, and before doing that I suggest buying/checking out a copy of the book The Design and Implementation of the FreeBSD Operating System. Many of your questions can be possibly answered better by taking a computer architecture and/or operating systems course, as many of the questions and ideas you have most likely apply to real-time operating systems, including Linux, OSX, Solaris and even (gasp) Windows, not just FreeBSD. Some of my 2 cents: Threading is known as LWP (Light-weight processes). Some differences are present, but the basic semantics of what one deems as non-threaded programs (processes), also applies to threads. Sharing, scheduling, and overall applied load are the overall big differences present in a threaded system, when compared to a procedural only system. Cheers and happy learning, -Garrett