60 lines
1.8 KiB
Text
60 lines
1.8 KiB
Text
<page xmlns="http://projectmallard.org/1.0/"
|
|
type="topic" style="task"
|
|
id="mem-swap">
|
|
|
|
<info>
|
|
<revision pkgversion="3.11" date="2014-01-28" status="final"/>
|
|
<link type="guide" xref="index#memory" group="memory" />
|
|
|
|
<include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
|
|
|
|
<credit type="author copyright">
|
|
<name>Phil Bull</name>
|
|
<email>philbull@gmail.com</email>
|
|
<years>2011</years>
|
|
</credit>
|
|
|
|
<credit type="author copyright">
|
|
<name>Michael Hill</name>
|
|
<email>mdhillca@gmail.com</email>
|
|
<years>2011, 2014</years>
|
|
</credit>
|
|
|
|
<desc>Swap memory allows your computer to run more applications at the same
|
|
time than will fit into the system memory (RAM).</desc>
|
|
</info>
|
|
|
|
<title>What is "swap" memory?</title>
|
|
|
|
<comment>
|
|
<cite date="2011-06-18" href="mailto:philbull@gmail.com">Phil Bull</cite>
|
|
<p>Explain what swap is and how it helps. Explain that the computer may run
|
|
slowly if it's swapping too much.</p>
|
|
</comment>
|
|
|
|
<p>Swap memory or <em>swap space</em> is the on-disk component of the virtual
|
|
memory system. It is pre-configured as a <em>swap partition</em> or a
|
|
<em>swap file</em> when Linux is first installed, but can also be added
|
|
later.</p>
|
|
|
|
<note>
|
|
<p>Disk access is <em>very</em> slow compared to memory access. The system
|
|
runs more slowly if there is excessive swapping, or <em>thrashing</em>,
|
|
when the system is unable to find enough free memory. In this situation the
|
|
only solution is to add more RAM.</p>
|
|
</note>
|
|
|
|
<p>To see whether swapping, or <em>paging</em>, has become a performance
|
|
issue:</p>
|
|
|
|
<steps>
|
|
<item>
|
|
<p>Click the <gui>Resources</gui> tab.</p>
|
|
</item>
|
|
<item>
|
|
<p>The <gui>Memory and Swap History</gui> graph shows memory and swap use
|
|
as percentages.</p>
|
|
</item>
|
|
</steps>
|
|
|
|
</page>
|