Date: Thu, 20 Mar 2014 15:20:17 +0000 (UTC) From: Dru Lavigne <dru@FreeBSD.org> To: doc-committers@freebsd.org, svn-doc-all@freebsd.org, svn-doc-head@freebsd.org Subject: svn commit: r44296 - in head/en_US.ISO8859-1/books/handbook: bsdinstall config Message-ID: <201403201520.s2KFKHt9081748@svn.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: dru Date: Thu Mar 20 15:20:17 2014 New Revision: 44296 URL: http://svnweb.freebsd.org/changeset/doc/44296 Log: Incorporate 12.2 Initial Configuration - Partition Layout into 2.7 Allocating Disk Space. Sponsored by: iXsystems Modified: head/en_US.ISO8859-1/books/handbook/bsdinstall/chapter.xml head/en_US.ISO8859-1/books/handbook/config/chapter.xml Modified: head/en_US.ISO8859-1/books/handbook/bsdinstall/chapter.xml ============================================================================== --- head/en_US.ISO8859-1/books/handbook/bsdinstall/chapter.xml Thu Mar 20 14:51:31 2014 (r44295) +++ head/en_US.ISO8859-1/books/handbook/bsdinstall/chapter.xml Thu Mar 20 15:20:17 2014 (r44296) @@ -1232,6 +1232,104 @@ Trying to mount root from cd9660:/dev/is </mediaobject> </figure> + <para>This section describes what to consider when laying + out the disk partitions. It then demonstrates how to use both + the Guided Partitioning and Manual Partitioning screens.</para> + + <sect2 xml:id="configtuning-initial"> + <title>Designing the Partition Layout</title> + + <indexterm><primary>partition layout</primary></indexterm> + <indexterm> + <primary><filename>/etc</filename></primary> + </indexterm> + <indexterm> + <primary><filename>/var</filename></primary> + </indexterm> + <indexterm> + <primary><filename>/usr</filename></primary> + </indexterm> + + <para>When laying out file systems, remember that hard drives transfer data + faster from the outer tracks to the inner. Thus, smaller + and heavier-accessed file systems should be closer to the + outside of the drive, while larger partitions like + <filename>/usr</filename> should be placed toward the inner + parts of the disk. It is a good idea to create partitions + in an order similar to: <filename>/</filename>, swap, + <filename>/var</filename>, and + <filename>/usr</filename>.</para> + + <para>The size of the <filename>/var</filename> partition + reflects the intended machine's usage. This partition is + used to hold mailboxes, log files, and printer spools. + Mailboxes and log files can grow to unexpected sizes + depending on the number of users and how long log files are + kept. On average, most users rarely need more than about a + gigabyte of free disk space in + <filename>/var</filename>.</para> + + <note> + <para>Sometimes, a lot of disk space is required in + <filename>/var/tmp</filename>. When new software is + installed, the packaging tools + extract a temporary copy of the packages under + <filename>/var/tmp</filename>. Large software packages, + like <application>Firefox</application>, + <application>OpenOffice</application> or + <application>LibreOffice</application> may be tricky to + install if there is not enough disk space under + <filename>/var/tmp</filename>.</para> + </note> + + <para>The <filename>/usr</filename> partition holds many of + the files which support the system, including the &os; Ports + Collection and system source code. At least 2 gigabytes is + recommended for this partition.</para> + + <para>When selecting partition sizes, keep the space + requirements in mind. Running out of space in one partition + while barely using another can be a hassle.</para> + + <indexterm> + <primary>swap sizing</primary> + </indexterm> + <indexterm> + <primary>swap partition</primary> + </indexterm> + + <para>As a rule of thumb, the swap partition should be about + double the size of physical memory (<acronym>RAM</acronym>). + Systems with minimal <acronym>RAM</acronym> may perform + better with more swap. Configuring too little swap can + lead to inefficiencies in the <acronym>VM</acronym> page + scanning code and might create issues later if more memory + is added.</para> + + <para>On larger systems with multiple <acronym>SCSI</acronym> + disks or multiple <acronym>IDE</acronym> disks operating + on different controllers, it is recommended that swap be + configured on each drive, up to four drives. The swap + partitions should be approximately the same size. The + kernel can handle arbitrary sizes but internal data + structures scale to 4 times the largest swap partition. + Keeping the swap partitions near the same size will allow + the kernel to optimally stripe swap space across disks. + Large swap sizes are fine, even if swap is not used much. + It might be easier to recover from a runaway program before + being forced to reboot.</para> + + <para>By properly partitioning a system, fragmentation + introduced in the smaller write heavy partitions will not + bleed over into the mostly read partitions. Keeping the + write loaded partitions closer to the disk's edge will + increase I/O performance in the partitions where it occurs + the most. While I/O performance in the larger partitions + may be needed, shifting them more toward the edge of the + disk will not lead to a significant performance improvement + over moving <filename>/var</filename> to the edge.</para> + </sect2> + <sect2 xml:id="bsdinstall-part-guided"> <title>Guided Partitioning</title> Modified: head/en_US.ISO8859-1/books/handbook/config/chapter.xml ============================================================================== --- head/en_US.ISO8859-1/books/handbook/config/chapter.xml Thu Mar 20 14:51:31 2014 (r44295) +++ head/en_US.ISO8859-1/books/handbook/config/chapter.xml Thu Mar 20 15:20:17 2014 (r44296) @@ -61,11 +61,6 @@ <itemizedlist> <listitem> - <para>How to efficiently work with file systems and swap - partitions.</para> - </listitem> - - <listitem> <para>The basics of <filename>rc.conf</filename> configuration and <filename>/usr/local/etc/rc.d</filename> startup scripts.</para> @@ -110,141 +105,6 @@ </itemizedlist> </sect1> - <sect1 xml:id="configtuning-initial"> - <title>Initial Configuration</title> - - <sect2> - <title>Partition Layout</title> - - <indexterm><primary>partition layout</primary></indexterm> - <indexterm> - <primary><filename>/etc</filename></primary> - </indexterm> - <indexterm> - <primary><filename>/var</filename></primary> - </indexterm> - <indexterm> - <primary><filename>/usr</filename></primary> - </indexterm> - - <sect3> - <title>Base Partitions</title> - - <para>When laying out file systems with &man.bsdlabel.8; or - &man.sysinstall.8;, remember that hard drives transfer data - faster from the outer tracks to the inner. Thus, smaller - and heavier-accessed file systems should be closer to the - outside of the drive, while larger partitions like - <filename>/usr</filename> should be placed toward the inner - parts of the disk. It is a good idea to create partitions - in an order similar to: <filename>/</filename>, swap, - <filename>/var</filename>, and - <filename>/usr</filename>.</para> - - <para>The size of the <filename>/var</filename> partition - reflects the intended machine's usage. This partition is - used to hold mailboxes, log files, and printer spools. - Mailboxes and log files can grow to unexpected sizes - depending on the number of users and how long log files are - kept. On average, most users rarely need more than about a - gigabyte of free disk space in - <filename>/var</filename>.</para> - - <note> - <para>Sometimes, a lot of disk space is required in - <filename>/var/tmp</filename>. When new software is - installed with &man.pkg.add.1;, the packaging tools - extract a temporary copy of the packages under - <filename>/var/tmp</filename>. Large software packages, - like <application>Firefox</application>, - <application>OpenOffice</application> or - <application>LibreOffice</application> may be tricky to - install if there is not enough disk space under - <filename>/var/tmp</filename>.</para> - </note> - - <para>The <filename>/usr</filename> partition holds many of - the files which support the system, including the &os; Ports - Collection and system source code. At least 2 gigabytes is - recommended for this partition.</para> - - <para>When selecting partition sizes, keep the space - requirements in mind. Running out of space in one partition - while barely using another can be a hassle.</para> - - <note> - <para>The <literal>Auto-defaults</literal> partition sizer - used by &man.sysinstall.8; will sometimes select smaller - than adequate <filename>/var</filename> and - <filename>/</filename> partitions. Partition wisely and - generously.</para> - </note> - </sect3> - - <sect3 xml:id="swap-design"> - <title>Swap Partition</title> - - <indexterm> - <primary>swap sizing</primary> - </indexterm> - <indexterm> - <primary>swap partition</primary> - </indexterm> - - <para>As a rule of thumb, the swap partition should be about - double the size of physical memory (<acronym>RAM</acronym>) - as the kernel's virtual memory (<acronym>VM</acronym>) - paging algorithms are tuned to perform best when the swap - partition is at least two times the size of main memory. - Systems with minimal <acronym>RAM</acronym> may perform - better with more swap. Configuring too little swap can - lead to inefficiencies in the <acronym>VM</acronym> page - scanning code and might create issues later if more memory - is added.</para> - - <para>On larger systems with multiple <acronym>SCSI</acronym> - disks or multiple <acronym>IDE</acronym> disks operating - on different controllers, it is recommended that swap be - configured on each drive, up to four drives. The swap - partitions should be approximately the same size. The - kernel can handle arbitrary sizes but internal data - structures scale to 4 times the largest swap partition. - Keeping the swap partitions near the same size will allow - the kernel to optimally stripe swap space across disks. - Large swap sizes are fine, even if swap is not used much. - It might be easier to recover from a runaway program before - being forced to reboot.</para> - </sect3> - - <sect3> - <title>Why Partition?</title> - - <para>Several users think a single large partition will be - fine, but there are several reasons why this is a bad idea. - First, each partition has different operational - characteristics and separating them allows the file system - to tune accordingly. For example, the root and - <filename>/usr</filename> partitions are read-mostly, with - few writes, while a lot of reads and writes could occur in - <filename>/var</filename> and - <filename>/var/tmp</filename>.</para> - - <para>By properly partitioning a system, fragmentation - introduced in the smaller write heavy partitions will not - bleed over into the mostly read partitions. Keeping the - write loaded partitions closer to the disk's edge will - increase I/O performance in the partitions where it occurs - the most. While I/O performance in the larger partitions - may be needed, shifting them more toward the edge of the - disk will not lead to a significant performance improvement - over moving <filename>/var</filename> to the edge. Finally, - there are safety concerns. A smaller, neater root partition - which is mostly read-only has a greater chance of surviving - a bad crash.</para> - </sect3> - </sect2> - </sect1> - <sect1 xml:id="configtuning-core-configuration"> <title>Core Configuration</title>
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201403201520.s2KFKHt9081748>