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[gnome-system-monitor/wip/mallard-help: 47/60] Review memory-map-use help page

commit 95a59c0b5056cc5048dfa1fc62de287a98b43d27
Author: Ekaterina Gerasimova <kittykat3756 gmail com>
Date:   Tue Jan 28 13:15:18 2014 +0000

    Review memory-map-use help page

 help/C/memory-map-use.page |  184 ++++++++++++++++++--------------------------
 1 files changed, 76 insertions(+), 108 deletions(-)
---
diff --git a/help/C/memory-map-use.page b/help/C/memory-map-use.page
index 6c9c5fc..80defe9 100644
--- a/help/C/memory-map-use.page
+++ b/help/C/memory-map-use.page
@@ -1,8 +1,9 @@
 <page xmlns="http://projectmallard.org/1.0/";
       type="topic" style="task"
       id="memory-map-use">
+
   <info>
-    <revision version="0.2" pkgversion="3.11" date="2014-01-26" status="incomplete"/>
+    <revision pkgversion="3.11" date="2014-01-28" status="candidate"/>
     <link type="guide" xref="index" group="memory" />
 
     <include href="legal.xml" xmlns="http://www.w3.org/2001/XInclude"/>
@@ -19,7 +20,7 @@
       <years>2011, 2014</years>
     </credit>
 
-    <desc>Display the memory map of a process.</desc>
+    <desc>View the memory map of a process.</desc>
   </info>
 
   <title>Using memory maps</title>
@@ -29,7 +30,8 @@
     <p>Explain how to use the Memory Map feature.</p>
   </comment>
 
-  <p>To display the <link xref="memory-map-what">memory map</link> of a process:</p>
+  <p>To display the <link xref="memory-map-what">memory map</link> of a
+  process:</p>
 
   <steps>
     <item><p>Click the <gui>Processes</gui> tab.</p></item>
@@ -37,137 +39,103 @@
     <item><p>Click <gui>Memory Maps</gui>.</p></item>
   </steps>
 
-  <p>When a program is launched, the system assigns it a unique process ID (PID)
- and its <em>instructions</em> and <em>data</em> are loaded into memory in
- <em>pages</em>. The page table of each process maps the correspondence between
- its pages in virtual memory and their location in physical memory. The
- <gui>memory map</gui> displays the total virtual memory use of the process, and
- can be used to determine the memory cost of running a single or multiple
- instances of the program, to ensure the use of the correct shared libraries, to
- see the results of adjusting various performance tuning parameters the program
- may have, or to diagnose issues such as memory leaks.</p>
-
-  <p>If multiple copies of a program are running, the instructions (or <em>text</em>)
- of the program only need to be loaded once into physical memory. Each time a
- new instance of the program is launched (as a unique process with its own virtual
- memory pages), its page table maps the location of the text in virtual memory to
- those instructions in the original real memory location. In addition, any dynamic
- shared libraries used by the process appear as distinct in virtual memory, but
- are shared references to a single copy of the library's text segment in real
- memory. When accounting for the total memory use of a process, it is important
- to note that the cost of shared libraries loaded into memory can be spread
- across all the processes currently using them.</p>
-
-  <p>When the system needs more pages of memory than are available, some of the
- existing pages will be <em>paged out</em> or written to the <link xref="mem-swap">swap space</link>.
- Text pages are flagged read-execute in memory and don't need to be written to
- swap since they can be re-loaded from their original location on disk. Data
- pages have read-write permissions, and if modified when in memory, they are
- labeled <em>dirty</em>, and when designated for swapping, must be paged out.
- When a page in swap space is required by a running process, it needs to be
- swapped back in before use, perhaps causing another page to be paged out.</p>
+<section id="read">
+  <title>Reading the memory map:</title>
 
-  <p>Reading the memory map:</p>
   <list>
-
     <item>
       <p>Addresses are diplayed in hexadecimal (base 16).</p>
     </item>
     <item>
-      <p>Sizes are displayed in <link xref="units">IEC binary prefixes</link>.</p>
+      <p>Sizes are displayed in <link xref="units">IEC binary
+      prefixes</link>.</p>
     </item>
     <item>
-      <p>At runtime the process can allocate more memory dynamically into an area
- called the <em>heap</em>, and store arguments and variables into another area
- called the <em>stack</em>.</p>
+      <p>At runtime the process can allocate more memory dynamically into an
+      area called the <em>heap</em>, and store arguments and variables into
+      another area called the <em>stack</em>.</p>
     </item>
     <item>
       <p>The program itself and each of the shared libraries has three entries
- each, one for the read-execute text segment, one for the read-write data segment
- and one for a read-only data segment. Both data segments need to be paged out
- at swap time.</p>
+      each, one for the read-execute text segment, one for the read-write data
+      segment and one for a read-only data segment. Both data segments need to
+      be paged out at swap time.</p>
     </item>
   </list>
 
 <table shade="rows">
-
   <tr>
-       <td><p>Properties</p></td>
-   </tr>
-
+        <td><p>Properties</p></td>
+  </tr>
   <tr>
-       <td><p>Filename</p></td>
-       <td><p>The location of a shared library that is currently used by the process.
- If this field is blank, the memory information in this row describes memory
- that is owned by the process whose name is displayed above the memory-map
- table.</p></td>
-   </tr>
-
+         <td><p>Filename</p></td>
+         <td><p>The location of a shared library that is currently used by the
+    process. If this field is blank, the memory information in this row
+    describes memory that is owned by the process whose name is displayed above
+    the memory-map table.</p></td>
+  </tr>
   <tr>
-       <td><p>VM Start</p></td>
-       <td><p>The address at which the memory segment begins. VM Start, VM End and VM
- Offset together specify the location on disk to which the shared library is
- mapped.</p></td>
-   </tr>
-
+         <td><p>VM Start</p></td>
+         <td><p>The address at which the memory segment begins. VM Start, VM End and
+    VM Offset together specify the location on disk to which the shared library
+    is mapped.</p></td>
+  </tr>
   <tr>
-       <td><p>VM End</p></td>
-       <td><p>The address at which the memory segment ends.</p></td>
-   </tr>
-
+         <td><p>VM End</p></td>
+         <td><p>The address at which the memory segment ends.</p></td>
+  </tr>
   <tr>
-       <td><p>VM Offset</p></td>
-       <td><p>The location of the address within the memory segment, measured from VM
- Start.</p></td>
-   </tr>
-
+         <td><p>VM Offset</p></td>
+         <td><p>The location of the address within the memory segment, measured from
+    VM Start.</p></td>
+  </tr>
   <tr>
-       <td><p>VM Size</p></td>
-       <td><p>The size of the memory segment.</p></td>
-   </tr>
-
+         <td><p>VM Size</p></td>
+         <td><p>The size of the memory segment.</p></td>
+  </tr>
   <tr>
-       <td><p>Flags</p></td>
-       <td><p>The following flags describe the different types of memory-segment access
- that the process can have:</p>
+         <td><p>Flags</p></td>
+         <td><p>The following flags describe the different types of memory-segment
+    access that the process can have:</p>
     <terms>
-    <item>
-      <title><gui>p</gui></title>
-    <p>The memory segment is private to the process, and is not accessible to
- other processes.</p>
-    </item>
-    <item>
-      <title><gui>r</gui></title>
-    <p>The process has permission to read from the memory segment.</p>
-    </item>
-    <item>
-      <title><gui>s</gui></title>
-    <p>The memory segment is shared with other processes.</p>
-    </item>
-    <item>
-      <title><gui>w</gui></title>
-    <p>The process has permission to write into the memory segment.</p>
-    </item>
-    <item>
-      <title><gui>x</gui></title>
-    <p>The process has permission to execute instructions that are contained
- within the memory segment.</p>
-    </item>
+      <item>
+        <title><gui>p</gui></title>
+        <p>The memory segment is private to the process, and is not accessible
+        to other processes.</p>
+      </item>
+      <item>
+        <title><gui>r</gui></title>
+        <p>The process has permission to read from the memory segment.</p>
+      </item>
+      <item>
+        <title><gui>s</gui></title>
+        <p>The memory segment is shared with other processes.</p>
+      </item>
+      <item>
+        <title><gui>w</gui></title>
+        <p>The process has permission to write into the memory segment.</p>
+      </item>
+      <item>
+        <title><gui>x</gui></title>
+        <p>The process has permission to execute instructions that are
+        contained within the memory segment.</p>
+      </item>
     </terms>
-   </td>
-   </tr>
+    </td>
+  </tr>
   <tr>
-       <td><p>Device</p></td>
-       <td><p>The major and minor numbers of the device on which the shared library
- filename is located. Together these specify a partition on the system.</p></td>
-   </tr>
+         <td><p>Device</p></td>
+         <td><p>The major and minor numbers of the device on which the shared
+    library filename is located. Together these specify a partition on the
+    system.</p></td>
+  </tr>
   <tr>
-       <td><p>Inode</p></td>
-       <td><p>The inode on the device from which the shared library location is loaded
- into memory. An inode is the structure the filesystem uses to store a file, and
- the number assigned to it is unique.</p></td>
-   </tr>
-
+         <td><p>Inode</p></td>
+         <td><p>The inode on the device from which the shared library location is
+    loaded into memory. An inode is the structure the filesystem uses to store
+    a file, and the number assigned to it is unique.</p></td>
+  </tr>
 </table>
 
+</section>
 </page>
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