diff options
author | Bruce Dubbs <bdubbs@linuxfromscratch.org> | 2009-09-10 06:12:28 +0000 |
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committer | Bruce Dubbs <bdubbs@linuxfromscratch.org> | 2009-09-10 06:12:28 +0000 |
commit | 8988b94cd0f916f39b26d0bd6b122c69c2d9e910 (patch) | |
tree | 84c90780bd5f7c03650e027c160dc0c80e21ee5b | |
parent | b8f47e78d4b9cb44086c8a4e0fef658eba4193d2 (diff) |
Added a section to the Preface about LFS supported architectures
git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@9065 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689
-rw-r--r-- | chapter01/changelog.xml | 10 | ||||
-rw-r--r-- | general.ent | 4 | ||||
-rw-r--r-- | prologue/architecture.xml | 66 | ||||
-rw-r--r-- | prologue/preface.xml | 1 |
4 files changed, 79 insertions, 2 deletions
diff --git a/chapter01/changelog.xml b/chapter01/changelog.xml index f34c30dda..a9ad6d065 100644 --- a/chapter01/changelog.xml +++ b/chapter01/changelog.xml @@ -38,6 +38,16 @@ --> <listitem> + <para>2009-09-10</para> + <itemizedlist> + <listitem> + <para>[bdubbs] - Added a section to the Preface about LFS + supported architectures.</para> + </listitem> + </itemizedlist> + </listitem> + + <listitem> <para>2009-09-02</para> <itemizedlist> <listitem> diff --git a/general.ent b/general.ent index a9fa51bfc..8410d5a64 100644 --- a/general.ent +++ b/general.ent @@ -1,6 +1,6 @@ <?xml version="1.0" encoding="ISO-8859-1"?> -<!ENTITY version "SVN-20090902"> -<!ENTITY releasedate "September 2, 2009"> +<!ENTITY version "SVN-20090910"> +<!ENTITY releasedate "September 10, 2009"> <!ENTITY copyrightdate "1999-2009"><!-- jhalfs needs a literal dash, not – --> <!ENTITY milestone "7.0"> <!ENTITY generic-version "development"> <!-- Use "development", "testing", or "x.y[-pre{x}]" --> diff --git a/prologue/architecture.xml b/prologue/architecture.xml new file mode 100644 index 000000000..75c29ce36 --- /dev/null +++ b/prologue/architecture.xml @@ -0,0 +1,66 @@ +<?xml version="1.0" encoding="ISO-8859-1"?> +<!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" + "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [ + <!ENTITY % general-entities SYSTEM "../general.ent"> + %general-entities; +]> + +<sect1 id="pre-architecture"> + <?dbhtml filename="architecture.html"?> + + <title>LFS Target Architectures</title> + +<para>The primary target architecture of LFS is the 32-bit Intel CPU. If you +have not built an LFS system before, you should probably start with that +target. The 32-bit architecture is the most widely supported Linux system and +is most compatible with both open source and proprietary software.</para> + +<para>On the other hand, the instructions in this book are known to work, with +some modifications, with both Power PC and 64-bit AMD/Intel CPUs. To build a +system that utilizes these CPUs, the main prerequsite in addition to those on +the next few pages, is an existing system such as an earlier LFS system, +Ubuntu, Red Hat/Fedora, SuSE, or other distribution that targets the system +that you have. Also note that a 32-bit system can be installed and used as a +host system on a 64-bit AMD/Intel system.</para> + +<para>If you decide to target a 64-bit AMD/Intel system, LFS does have some +limitations. First, it does not currently provide instructions for a 64-bit +boot loader. If there is an existing boot loader, it can be used to boot to +any LFS system you build, but <xref linkend="ch-bootable-grub"/> cannot be +built on a 64-bit system.</para> + +<para>Some other facts about a 64-bit systems need to be added here. When +compared to a 32-bit system, the sizes of executable programs are slightly +larger and the execution speeds are only slightly faster. For example, in a +test build of LFS-6.5 on a Core2Duo CPU based system, the following statistics +were measured:</para> + +<screen><computeroutput>Architecture Build Time Build Size +32-bit 198.5 minutes 648 MB +64-bit 190.6 minutes 709 MB</computeroutput></screen> + +<para>As you can see, the 64-bit build is only 4% faster and is 9% larger than +the 32-bit build. The gain from going to a 64-bit system is relatively +minimal. Of course, if you have more than 4GB of RAM or want to manipulate +data that exceeds 4GB, the advantages of a 64-bit system are substantial.</para> + +<para>The default 64-bit build that results from LFS is considered a "pure" +64-bit system. That is, it supports 64-bit executables only. Building a +"multi-lib" system requires building many applications twice, once for a 32-bit +system and once for a 64-bit system. Currently this is not directly supported +in the book, but is under consideration for a future release. In the meantime, +you can refer to the <ulink url="http://trac.cross-lfs.org/">Cross Linux From +Scratch</ulink> project for this advanced topic.</para> + +<para>There is one last comment about 64-bit systems. There are some packages +that cannot currently be built in a "pure" 64-bit system or require specialized +build instructions. Generally, these packages have some embedded 32-bit +specific assembly language instructions that fail when building on a 64-bit +system. Examples include the <ulink +url="http://www.linuxfromscratch.org/blfs/view/cvs/">Beyond Linux From Scratch +(BLFS)</ulink> packages Zip and some Xorg drivers. Many of these problems can +be worked around, but may require some specialized procedures or +patches.</para> + +</sect1> + diff --git a/prologue/preface.xml b/prologue/preface.xml index 5ad84923e..fde09453d 100644 --- a/prologue/preface.xml +++ b/prologue/preface.xml @@ -13,6 +13,7 @@ <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" href="foreword.xml"/> <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" href="audience.xml"/> + <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" href="architecture.xml"/> <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" href="prerequisites.xml"/> <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" href="hostreqs.xml"/> <xi:include xmlns:xi="http://www.w3.org/2003/XInclude" href="typography.xml"/> |