top命令

本是古典何须时尚 2022-09-19 05:20 256阅读 0赞

来源《鸟哥的linux私房菜》

top：动态观察程序的变化

[?][Link 1]

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 <tbody> 
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   <td> 
    <div> 
     <div> 
      <code>[root</code> 
      <code>@linux</code> 
      <code>~]</code> 
      <code># top [-d] | top [-bnp]</code> 
     </div> 
     <div> 
      <code>参数：</code> 
     </div> 
     <div> 
      <code>-d ：后面可以接秒数，就是整个程序画面更新的秒数。预设是</code> 
      <code>5</code> 
      <code>秒；</code> 
     </div> 
     <div> 
      <code>-b ：以批次的方式执行 top ，还有更多的参数可以使用喔！</code> 
     </div> 
     <div> 
      <code>通常会搭配数据流重导向来将批次的结果输出成为档案。</code> 
     </div> 
     <div> 
      <code>-n ：与 -b 搭配，意义是，需要进行几次 top 的输出结果。</code> 
     </div> 
     <div> 
      <code>-p ：指定某些个 </code> 
      <code>PID</code> 
      <code>来进行观察监测而已。</code> 
     </div> 
     <div> 
      <code>在 top 执行过程当中可以使用的按键指令：</code> 
     </div> 
     <div> 
      <code>? ：显示在 top 当中可以输入的按键指令；</code> 
     </div> 
     <div> 
      <code>P</code> 
      <code> ：以 </code> 
      <code>CPU</code> 
      <code>的使用资源排序显示；</code> 
     </div> 
     <div> 
      <code>M</code> 
      <code> ：以 Memory 的使用资源排序显示；</code> 
     </div> 
     <div> 
      <code>N</code> 
      <code> ：以 </code> 
      <code>PID</code> 
      <code>来排序喔！</code> 
     </div> 
     <div> 
      <code>T</code> 
      <code> ：由该 Process 使用的 </code> 
      <code>CPU</code> 
      <code> 时间累积 (</code> 
      <code>TIME</code> 
      <code>+) 排序。</code> 
     </div> 
     <div> 
      <code>k ：给予某个 </code> 
      <code>PID</code> 
      <code>一个讯号 (signal)</code> 
     </div> 
     <div> 
      <code>r ：给予某个 </code> 
      <code>PID</code> 
      <code>重新制订一个 nice 值。</code> 
     </div> 
    </div> </td> 
  </tr> 
 </tbody> 
</table>

范例1：每两秒钟更新一次 top ，观察整体信息

[?][Link 1]

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      <code>[root</code> 
      <code>@linux</code> 
      <code>~]</code> 
      <code># top -d 2</code> 
     </div> 
     <div> 
      <code>top - </code> 
      <code>18</code> 
      <code>:</code> 
      <code>30</code> 
      <code>:</code> 
      <code>36</code> 
      <code>up </code> 
      <code>30</code> 
      <code>days, </code> 
      <code>7</code> 
      <code>min, </code> 
      <code>1</code> 
      <code>user, load average:</code> 
      <code>0</code> 
      <code>.</code> 
      <code>42</code> 
      <code>,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>48</code> 
      <code>,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>45</code> 
     </div> 
     <div> 
      <code>Tasks: </code> 
      <code>163</code> 
      <code>total, </code> 
      <code>1</code> 
      <code>running, </code> 
      <code>161</code> 
      <code>sleeping, </code> 
      <code>1</code> 
      <code>stopped,</code> 
      <code>0</code> 
      <code>zombie</code> 
     </div> 
     <div> 
      <code>Cpu(s): </code> 
      <code>4</code> 
      <code>.</code> 
      <code>7</code> 
      <code>% us,</code> 
      <code>4</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% sy,</code> 
      <code>6</code> 
      <code>.</code> 
      <code>3</code> 
      <code>% ni,</code> 
      <code>82</code> 
      <code>.</code> 
      <code>5</code> 
      <code>% id,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>4</code> 
      <code>% wa,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>1</code> 
      <code>% hi,</code> 
      <code>2</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% si</code> 
     </div> 
     <div> 
      <code>Mem: 1033592k total, 955252k used, 78340k free, 208648k buffers</code> 
     </div> 
     <div> 
      <code>Swap: 1052216k total, 728k used, 1051488k free, 360248k cached</code> 
     </div> 
     <div> 
      <code>&lt;==如果加入 k 或 r 时，就会有相关的字样出现在这里喔！</code> 
     </div> 
     <div></div> 
     <div> 
      <code>PID</code> 
      <code> USER</code> 
      <code>PR</code> 
      <code>NI</code> 
      <code>VIRT</code> 
      <code>RES</code> 
      <code>SHR</code> 
      <code> S</code> 
      <code>%</code> 
      <code>CPU</code> 
      <code>%</code> 
      <code>MEM</code> 
      <code>TIME</code> 
      <code>+ </code> 
      <code>COMMAND</code> 
     </div> 
     <div> 
      <code>3981</code> 
      <code> apache </code> 
      <code>34</code> 
      <code> 19</code> 
      <code>84012</code> 
      <code>11m </code> 
      <code>7352</code> 
      <code>S</code> 
      <code> 17</code> 
      <code>.</code> 
      <code>3</code> 
      <code> 1</code> 
      <code>.</code> 
      <code>2</code> 
      <code> 0</code> 
      <code>:</code> 
      <code>00</code> 
      <code>.</code> 
      <code>09</code> 
      <code>httpd</code> 
     </div> 
     <div> 
      <code>1454</code> 
      <code> mysql </code> 
      <code>16</code> 
      <code> 0</code> 
      <code>289m 40m </code> 
      <code>2228</code> 
      <code>S</code> 
      <code>3</code> 
      <code>.</code> 
      <code>8</code> 
      <code>4</code> 
      <code>.</code> 
      <code>0</code> 
      <code>115</code> 
      <code>:</code> 
      <code>01</code> 
      <code>.</code> 
      <code>32</code> 
      <code>mysqld</code> 
     </div> 
     <div> 
      <code>3985</code> 
      <code> dmtsai </code> 
      <code>15</code> 
      <code> 0</code> 
      <code>2148</code> 
      <code>904</code> 
      <code>668</code> 
      <code>R</code> 
      <code>3</code> 
      <code>.</code> 
      <code>8</code> 
      <code>0</code> 
      <code>.</code> 
      <code>1</code> 
      <code>0</code> 
      <code>:</code> 
      <code>00</code> 
      <code>.</code> 
      <code>03</code> 
      <code>top</code> 
     </div> 
     <div> 
      <code>1</code> 
      <code> root </code> 
      <code>16</code> 
      <code>0</code> 
      <code>3552</code> 
      <code>552</code> 
      <code>472</code> 
      <code> S</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>0</code> 
      <code>.</code> 
      <code>1</code> 
      <code>0</code> 
      <code>:</code> 
      <code>08</code> 
      <code>.</code> 
      <code>90</code> 
      <code>init</code> 
     </div> 
     <div> 
      <code>2</code> 
      <code> root </code> 
      <code>RT</code> 
      <code>0</code> 
      <code>0</code> 
      <code>0</code> 
      <code>0</code> 
      <code> S</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>0</code> 
      <code>:</code> 
      <code>52</code> 
      <code>.</code> 
      <code>76</code> 
      <code>migration/</code> 
      <code>0</code> 
     </div> 
     <div> 
      <code>3</code> 
      <code> root </code> 
      <code>34</code> 
      <code>19</code> 
      <code>0</code> 
      <code>0</code> 
      <code>0</code> 
      <code> S</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>0</code> 
      <code>:</code> 
      <code>03</code> 
      <code>.</code> 
      <code>01</code> 
      <code>ksoftirqd/</code> 
      <code>0</code> 
     </div> 
    </div> </td> 
  </tr> 
 </tbody> 
</table>

范例2：将 top 的信息进行 2 次，然后将结果输出到 /tmp/top.txt

[?][Link 1]

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      <code>[root</code> 
      <code>@linux</code> 
      <code>~]</code> 
      <code># top -b -n 2 &gt; /tmp/top.txt</code> 
     </div> 
     <div> 
      <code># 这样一来，嘿嘿！就可以将 top 的信息存到 /tmp/top.txt 档案中了。</code> 
     </div> 
    </div> </td> 
  </tr> 
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</table>

范例3：假设 10604 是一个已经存在的 PID ，仅观察该程序？

[?][Link 1]

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      <code>[root</code> 
      <code>@linux</code> 
      <code>~]</code> 
      <code># top -d 2 -p10604</code> 
     </div> 
     <div> 
      <code>top - </code> 
      <code>13</code> 
      <code>:</code> 
      <code>53</code> 
      <code>:</code> 
      <code>00</code> 
      <code>up </code> 
      <code>51</code> 
      <code>days, </code> 
      <code>2</code> 
      <code>:</code> 
      <code>27</code> 
      <code>,</code> 
      <code>1</code> 
      <code>user, load average:</code> 
      <code>0</code> 
      <code>.</code> 
      <code>00</code> 
      <code>,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>00</code> 
      <code>,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>00</code> 
     </div> 
     <div> 
      <code>Tasks: </code> 
      <code>1</code> 
      <code>total, </code> 
      <code>0</code> 
      <code>running, </code> 
      <code>1</code> 
      <code>sleeping,</code> 
      <code>0</code> 
      <code>stopped, </code> 
      <code>0</code> 
      <code> zombie</code> 
     </div> 
     <div> 
      <code>Cpu(s): </code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% us,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% sy,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% ni,</code> 
      <code>100</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% id,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% wa,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% hi,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% si</code> 
     </div> 
     <div> 
      <code>Mem: 385676k total, 371760k used, 13916k free, 131164k buffers</code> 
     </div> 
     <div> 
      <code>Swap: 1020116k total, 880k used, 1019236k free, 95772k cached</code> 
     </div> 
     <div></div> 
     <div> 
      <code>PID</code> 
      <code> USER</code> 
      <code>PR</code> 
      <code>NI</code> 
      <code>VIRT</code> 
      <code>RES</code> 
      <code>SHR</code> 
      <code> S</code> 
      <code>%</code> 
      <code>CPU</code> 
      <code>%</code> 
      <code>MEM</code> 
      <code>TIME</code> 
      <code>+ </code> 
      <code>COMMAND</code> 
     </div> 
     <div> 
      <code>10604</code> 
      <code> root </code> 
      <code>16</code> 
      <code>0</code> 
      <code>5396</code> 
      <code>1544</code> 
      <code>1244</code> 
      <code> S</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>0</code> 
      <code>.</code> 
      <code>4</code> 
      <code>0</code> 
      <code>:</code> 
      <code>00</code> 
      <code>.</code> 
      <code>07</code> 
      <code>bash</code> 
     </div> 
    </div> </td> 
  </tr> 
 </tbody> 
</table>

范例四：承上题，上面的 NI 值是 0 ，想要改成 10 的话？

[?][Link 1]

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     <div> 
      <code># 在范例三的 top 画面当中直接按下 r 之后，会出现如下的图样！</code> 
     </div> 
     <div> 
      <code>top - </code> 
      <code>13</code> 
      <code>:</code> 
      <code>53</code> 
      <code>:</code> 
      <code>00</code> 
      <code>up </code> 
      <code>51</code> 
      <code>days, </code> 
      <code>2</code> 
      <code>:</code> 
      <code>27</code> 
      <code>,</code> 
      <code>1</code> 
      <code>user, load average:</code> 
      <code>0</code> 
      <code>.</code> 
      <code>00</code> 
      <code>,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>00</code> 
      <code>,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>00</code> 
     </div> 
     <div> 
      <code>Tasks: </code> 
      <code>1</code> 
      <code>total, </code> 
      <code>0</code> 
      <code>running, </code> 
      <code>1</code> 
      <code>sleeping,</code> 
      <code>0</code> 
      <code>stopped, </code> 
      <code>0</code> 
      <code> zombie</code> 
     </div> 
     <div> 
      <code>Cpu(s): </code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% us,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% sy,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% ni,</code> 
      <code>100</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% id,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% wa,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% hi,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% si</code> 
     </div> 
     <div> 
      <code>Mem: 385676k total, 371760k used, 13916k free, 131164k buffers</code> 
     </div> 
     <div> 
      <code>Swap: 1020116k total, 880k used, 1019236k free, 95772k cached</code> 
     </div> 
     <div> 
      <code>PID</code> 
      <code> to renice: </code> 
      <code>10604</code> 
     </div> 
     <div></div> 
     <div> 
      <code>PID</code> 
      <code> USER</code> 
      <code>PR</code> 
      <code>NI</code> 
      <code>VIRT</code> 
      <code>RES</code> 
      <code>SHR</code> 
      <code> S</code> 
      <code>%</code> 
      <code>CPU</code> 
      <code>%</code> 
      <code>MEM</code> 
      <code>TIME</code> 
      <code>+ </code> 
      <code>COMMAND</code> 
     </div> 
     <div> 
      <code>10604</code> 
      <code> root </code> 
      <code>16</code> 
      <code>0</code> 
      <code>5396</code> 
      <code>1544</code> 
      <code>1244</code> 
      <code> S</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>0</code> 
      <code>.</code> 
      <code>4</code> 
      <code>0</code> 
      <code>:</code> 
      <code>00</code> 
      <code>.</code> 
      <code>07</code> 
      <code>bash</code> 
     </div> 
     <div> 
      <code># 之后，可以输入 nice 值了！</code> 
     </div> 
     <div> 
      <code>top - </code> 
      <code>13</code> 
      <code>:</code> 
      <code>53</code> 
      <code>:</code> 
      <code>00</code> 
      <code>up </code> 
      <code>51</code> 
      <code>days, </code> 
      <code>2</code> 
      <code>:</code> 
      <code>27</code> 
      <code>,</code> 
      <code>1</code> 
      <code>user, load average:</code> 
      <code>0</code> 
      <code>.</code> 
      <code>00</code> 
      <code>,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>00</code> 
      <code>,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>00</code> 
     </div> 
     <div> 
      <code>Tasks: </code> 
      <code>1</code> 
      <code>total, </code> 
      <code>0</code> 
      <code>running, </code> 
      <code>1</code> 
      <code>sleeping,</code> 
      <code>0</code> 
      <code>stopped, </code> 
      <code>0</code> 
      <code> zombie</code> 
     </div> 
     <div> 
      <code>Cpu(s): </code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% us,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% sy,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% ni,</code> 
      <code>100</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% id,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% wa,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% hi,</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>% si</code> 
     </div> 
     <div> 
      <code>Mem: 385676k total, 371760k used, 13916k free, 131164k buffers</code> 
     </div> 
     <div> 
      <code>Swap: 1020116k total, 880k used, 1019236k free, 95772k cached</code> 
     </div> 
     <div> 
      <code>Renice </code> 
      <code>PID</code> 
      <code>10604</code> 
      <code>to value: </code> 
      <code>10</code> 
     </div> 
     <div></div> 
     <div> 
      <code>PID</code> 
      <code> USER</code> 
      <code>PR</code> 
      <code>NI</code> 
      <code>VIRT</code> 
      <code>RES</code> 
      <code>SHR</code> 
      <code> S</code> 
      <code>%</code> 
      <code>CPU</code> 
      <code>%</code> 
      <code>MEM</code> 
      <code>TIME</code> 
      <code>+ </code> 
      <code>COMMAND</code> 
     </div> 
     <div> 
      <code>10604</code> 
      <code>root </code> 
      <code>30</code> 
      <code>10</code> 
      <code>5396</code> 
      <code>1544</code> 
      <code>1244</code> 
      <code>S</code> 
      <code>0</code> 
      <code>.</code> 
      <code>0</code> 
      <code>0</code> 
      <code>.</code> 
      <code>4</code> 
      <code>0</code> 
      <code>:</code> 
      <code>00</code> 
      <code>.</code> 
      <code>07</code> 
      <code>bash</code> 
     </div> 
    </div> </td> 
  </tr> 
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</table>

[?][Link 1]

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     <div> 
      <code>top 也是个挺不错的程序观察工具！但不同于 ps 是静态的结果输出， top 这个程序可以持续的监测 (monitor) 整个系统的程序工作状态，例如上面的范例一所示啊！ 在预设的情况下，每次更新程序资源的时间为</code> 
      <code>5</code> 
      <code>秒，不过，可以使用 -d 来进行修改。 top 主要分为两个画面，上面的画面为整个系统的资源使用状态，基本上总共有六行， 显示的内容依序是：</code> 
     </div> 
     <div> 
      <code>• 第一行：显示系统已启动的时间、目前上线人数、系统整体的负载(load)。 比较需要注意的是系统的负载，三个数据分别代表</code> 
      <code>1</code> 
      <code>, </code> 
      <code>5</code> 
      <code>,</code> 
      <code>10</code> 
      <code>分钟的平均负载。 一般来说，这个负载值应该不太可能超过</code> 
      <code>1</code> 
      <code>才对，除非您的系统很忙碌。 如果持续高于</code> 
      <code>5</code> 
      <code>的话，那么.....仔细的看看到底是那个程序在影响整体系统吧！</code> 
     </div> 
     <div> 
      <code>• 第二行：显示的是目前的观察程序数量，比较需要注意的是最后的 zombie 那个数值，如果不是</code> 
      <code>0</code> 
      <code>，嘿嘿！好好看看到底是那个 process 变成疆尸了吧？！</code> 
     </div> 
     <div> 
      <code>• 第三行：显示的是 </code> 
      <code>CPU</code> 
      <code>的整体负载，每个项目可使用 ? 查阅。需要观察的是 id (idle) 的数值，一般来说，他应该要接近</code> 
      <code>100</code> 
      <code>% 才好，表示系统很少资源被使用啊！ ^</code> 
      <code>_</code> 
      <code>^。</code> 
     </div> 
     <div> 
      <code>• 第四行与第五行：表示目前的物理内存与虚拟内存 (Mem/Swap) 的使用情况。</code> 
     </div> 
     <div> 
      <code>• 第六行：这个是当在 top 程序当中输入指令时，显示状态的地方。 例如范例四就是一个简单的使用例子。</code> 
     </div> 
     <div> 
      <code>至于 top 底下的画面，则是每个 process 使用的资源情况。比较需要注意的是：</code> 
     </div> 
     <div> 
      <code>• </code> 
      <code>PID</code> 
      <code>：每个 process 的 </code> 
      <code>ID</code> 
      <code>啦！</code> 
     </div> 
     <div> 
      <code>• </code> 
      <code>USER</code> 
      <code>：该 process 所属的使用者；</code> 
     </div> 
     <div> 
      <code>• </code> 
      <code>PR</code> 
      <code>：Priority 的简写，程序的优先执行顺序，越小越早被执行；</code> 
     </div> 
     <div> 
      <code>• </code> 
      <code>NI</code> 
      <code>：Nice 的简写，与 Priority 有关，也是越小越早被执行；</code> 
     </div> 
     <div> 
      <code>• %</code> 
      <code>CPU</code> 
      <code>：</code> 
      <code>CPU</code> 
      <code>的使用率；</code> 
     </div> 
     <div> 
      <code>• %</code> 
      <code>MEM</code> 
      <code>：内存的使用率；</code> 
     </div> 
     <div> 
      <code>• </code> 
      <code>TIME</code> 
      <code>+：</code> 
      <code>CPU</code> 
      <code>使用时间的累加；</code> 
     </div> 
     <div> 
      <code>一般来说，如果鸟哥想要找出最损耗</code> 
      <code>CPU</code> 
      <code>资源的那个程序时，大多使用的就是 top 这支程序啦！然后强制以</code> 
      <code>CPU</code> 
      <code>使用资源来排序 (在 top 当中按下</code> 
      <code>P</code> 
      <code>即可)， 就可以很快的知道啦！</code> 
     </div> 
     <div> 
      <code></code>&nbsp; 
     </div> 
     <div> 
      <code></code>&nbsp; 
     </div> 
     <div> 
      <code><span style="font-family:宋体; font-size:12px">&nbsp; TOP命令是Linux下常用的性能分析工具，能够实时显示系统中各个进程的资源占用状况。</span></code> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; TOP是一个动态显示过程,即可以通过用户按键来不断刷新当前状态.如果在前台执行该命令,它将独占前台,直到用户终止该程序为止.比较准确的说,top命令提供了实时的对系统处理器的状态监视.它将显示系统中CPU最“敏感”的任务列表.该命令可以按CPU使用.内存使用和执行时间对任务进行排序；而且该命令的很多特性都可以通过交互式命令或者在个人定制文件中进行设定.</p> 
      <p></p> 
      <p>top - 12:38:33 up 50 days, 23:15,&nbsp; 7 users,&nbsp; load average: 60.58, 61.14, 61.22</p> 
      <p>Tasks: 203 total,&nbsp; 60 running, 139 sleeping,&nbsp;&nbsp; 4 stopped,&nbsp;&nbsp; 0 zombie</p> 
      <p>Cpu(s)&nbsp; : 27.0%us, 73.0%sy,&nbsp; 0.0%ni,&nbsp; 0.0%id,&nbsp; 0.0%wa,&nbsp; 0.0%hi,&nbsp; 0.0%si,&nbsp; 0.0%st</p> 
      <p>Mem:&nbsp;&nbsp; 1939780k total,&nbsp; 1375280k used,&nbsp;&nbsp; 564500k free,&nbsp;&nbsp; 109680k buffers</p> 
      <p>Swap:&nbsp; 4401800k total,&nbsp;&nbsp; 497456k used,&nbsp; 3904344k free,&nbsp;&nbsp; 848712k cached</p> 
      <p></p> 
      <p>PID USER&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; PR&nbsp; NI&nbsp; VIRT&nbsp; RES&nbsp; SHR S %CPU %MEM&nbsp;&nbsp;&nbsp; TIME+&nbsp; COMMAND&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>4338 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 627m 209m 207m R&nbsp;&nbsp;&nbsp; 0 11.0 297:14.76 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>4267 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 626m 144m 143m R&nbsp;&nbsp;&nbsp; 6&nbsp; 7.6&nbsp; 89:16.62 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>3458 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 672m 133m 124m R&nbsp;&nbsp;&nbsp; 0&nbsp; 7.1&nbsp;&nbsp; 1283:08 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>3478 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 672m 124m 115m R&nbsp;&nbsp;&nbsp; 0&nbsp; 6.6&nbsp;&nbsp; 1272:30 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>3395 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 672m 122m 113m R&nbsp;&nbsp;&nbsp; 0&nbsp; 6.5&nbsp;&nbsp; 1270:03 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>3480 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 672m 122m 109m R&nbsp;&nbsp;&nbsp; 8&nbsp; 6.4&nbsp;&nbsp; 1274:13 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>3399 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 672m 121m 110m R&nbsp;&nbsp;&nbsp; 0&nbsp; 6.4&nbsp;&nbsp; 1279:37 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>4261 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 634m 100m&nbsp; 99m R&nbsp;&nbsp;&nbsp; 0&nbsp; 5.3&nbsp; 86:13.90 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>25737 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 632m&nbsp; 81m&nbsp; 74m R&nbsp;&nbsp;&nbsp; 0&nbsp; 4.3 272:35.42 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>7072 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 626m&nbsp; 72m&nbsp; 71m R&nbsp;&nbsp;&nbsp; 0&nbsp; 3.8&nbsp;&nbsp; 6:35.68 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>16073 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 630m&nbsp; 68m&nbsp; 63m R&nbsp;&nbsp;&nbsp; 8&nbsp; 3.6 175:20.36 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>16140 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 630m&nbsp; 66m&nbsp; 60m R&nbsp;&nbsp;&nbsp; 0&nbsp; 3.5 175:13.42 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>16122 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 630m&nbsp; 66m&nbsp; 60m R&nbsp;&nbsp;&nbsp; 0&nbsp; 3.5 176:47.73 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>&nbsp; 786 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 627m&nbsp; 63m&nbsp; 63m R&nbsp;&nbsp;&nbsp; 0&nbsp; 3.4&nbsp;&nbsp; 1:54.93 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>4271 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 627m&nbsp; 59m&nbsp; 58m R&nbsp;&nbsp;&nbsp; 8&nbsp; 3.1&nbsp; 86:09.64 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>4273 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 627m&nbsp; 57m&nbsp; 56m R&nbsp;&nbsp;&nbsp; 8&nbsp; 3.0&nbsp; 84:38.20 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p>22670 oracle&nbsp;&nbsp;&nbsp; 25&nbsp;&nbsp; 0&nbsp; 626m&nbsp; 50m&nbsp; 49m R&nbsp;&nbsp;&nbsp; 0&nbsp; 2.7&nbsp; 84:55.82 oracle&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </p> 
      <p></p> 
      <p><span style="color:red">一</span><span style="color:red">.&nbsp; </span>TOP<span style="color:red">前五行统计信息</span></p> 
      <p>统计信息区前五行是系统整体的统计信息。</p> 
      <p></p> 
      <p><span style="color:red">1. </span><span style="color:red">第一行是任务队列信息</span></p> 
      <p>同 uptime&nbsp; 命令的执行结果:</p> 
      <p>[root@localhost ~]# uptime</p> 
      <p>13:22:30 up 8 min,&nbsp; 4 users,&nbsp; load average: 0.14, 0.38, 0.25</p> 
      <p></p> 
      <p>其内容如下：</p> 
      <table> 
       <tbody> 
        <tr> 
         <td> <p>12:38:33</p> </td> 
         <td> <p>当前时间</p> </td> 
        </tr> 
        <tr> 
         <td> <p>up 50days</p> </td> 
         <td> <p>系统运行时间，格式为时:分</p> </td> 
        </tr> 
        <tr> 
         <td> <p>1 user</p> </td> 
         <td> <p>当前登录用户数</p> </td> 
        </tr> 
        <tr> 
         <td> <p>load average: 0.06, 0.60, 0.48</p> </td> 
         <td> <p>系统负载，即任务队列的平均长度。 三个数值分别为&nbsp; <span style="color:red">1</span><span style="color:red">分钟、</span><span style="color:red">5</span><span style="color:red">分钟、</span><span style="color:red">15</span><span style="color:red">分钟前到现在的平均值</span>。</p> </td> 
        </tr> 
       </tbody> 
      </table> 
      <p></p> 
      <p><span style="color:red">2. </span><span style="color:red">第二、三行为进程和</span><span style="color:red">CPU</span><span style="color:red">的信息</span></p> 
      <p>当有多个CPU时，这些内容可能会超过两行。内容如下：</p> 
      <table> 
       <tbody> 
        <tr> 
         <td> <p>Tasks: 29 total</p> </td> 
         <td> <p>进程总数</p> </td> 
        </tr> 
        <tr> 
         <td> <p>1 running</p> </td> 
         <td> <p>正在运行的进程数</p> </td> 
        </tr> 
        <tr> 
         <td> <p>28 sleeping</p> </td> 
         <td> <p>睡眠的进程数</p> </td> 
        </tr> 
        <tr> 
         <td> <p>0 stopped</p> </td> 
         <td> <p>停止的进程数</p> </td> 
        </tr> 
        <tr> 
         <td> <p>0 zombie</p> </td> 
         <td> <p>僵尸进程数</p> </td> 
        </tr> 
        <tr> 
         <td> <p>Cpu(s): 0.3% us</p> </td> 
         <td> <p>用户空间占用CPU百分比</p> </td> 
        </tr> 
        <tr> 
         <td> <p>1.0% sy</p> </td> 
         <td> <p>内核空间占用CPU百分比</p> </td> 
        </tr> 
        <tr> 
         <td> <p>0.0% ni</p> </td> 
         <td> <p>用户进程空间内改变过优先级的进程占用CPU百分比</p> </td> 
        </tr> 
        <tr> 
         <td> <p>98.7% id</p> </td> 
         <td> <p>空闲CPU百分比</p> </td> 
        </tr> 
        <tr> 
         <td> <p>0.0% wa</p> </td> 
         <td> <p>等待输入输出的CPU时间百分比</p> </td> 
        </tr> 
        <tr> 
         <td> <p>0.0% hi</p> </td> 
        </tr> 
        <tr> 
         <td> <p>0.0% si</p> </td> 
        </tr> 
       </tbody> 
      </table> 
      <p></p> 
      <p><span style="color:red">3. </span><span style="color:red">第四五行为内存信息。</span></p> 
      <p>内容如下：</p> 
      <table> 
       <tbody> 
        <tr> 
         <td> <p><span style="color:red">Mem: </span>191272k total</p> </td> 
         <td> <p>物理内存总量</p> </td> 
        </tr> 
        <tr> 
         <td> <p>173656k used</p> </td> 
         <td> <p>使用的物理内存总量</p> </td> 
        </tr> 
        <tr> 
         <td> <p>17616k free</p> </td> 
         <td> <p>空闲内存总量</p> </td> 
        </tr> 
        <tr> 
         <td> <p>22052k buffers</p> </td> 
         <td> <p>用作内核缓存的内存量</p> </td> 
        </tr> 
        <tr> 
         <td> <p><span style="color:red">Swap:</span> 192772k total</p> </td> 
         <td> <p>交换区总量</p> </td> 
        </tr> 
        <tr> 
         <td> <p>0k used</p> </td> 
         <td> <p>使用的交换区总量</p> </td> 
        </tr> 
        <tr> 
         <td> <p>192772k free</p> </td> 
         <td> <p>空闲交换区总量</p> </td> 
        </tr> 
        <tr> 
         <td> <p>123988k cached</p> </td> 
         <td> <p>缓冲的交换区总量。 内存中的内容被换出到交换区，而后又被换入到内存，但使用过的交换区尚未被覆盖， 该数值即为这些<strong><span style="color:red">内容已存在于内存中</span></strong>的交换区的大小。相应的内存再次被换出时可不必再对交换区写入。</p> </td> 
        </tr> 
       </tbody> 
      </table> 
      <p></p> 
      <p></p> 
      <p><span style="color:red">二</span><span style="color:red">.&nbsp; </span><span style="color:red">进程信息</span></p> 
      <p></p> 
      <table> 
       <tbody> 
        <tr> 
         <td> <p>列名</p> </td> 
         <td> <p>含义</p> </td> 
        </tr> 
        <tr> 
         <td> <p>PID</p> </td> 
         <td> <p>进程id</p> </td> 
        </tr> 
        <tr> 
         <td> <p>PPID</p> </td> 
         <td> <p>父进程id</p> </td> 
        </tr> 
        <tr> 
         <td> <p>RUSER</p> </td> 
         <td> <p>Real user name</p> </td> 
        </tr> 
        <tr> 
         <td> <p>UID</p> </td> 
         <td> <p>进程所有者的用户id</p> </td> 
        </tr> 
        <tr> 
         <td> <p>USER</p> </td> 
         <td> <p>进程所有者的用户名</p> </td> 
        </tr> 
        <tr> 
         <td> <p>GROUP</p> </td> 
         <td> <p>进程所有者的组名</p> </td> 
        </tr> 
        <tr> 
         <td> <p>TTY</p> </td> 
         <td> <p>启动进程的终端名。不是从终端启动的进程则显示为 ?</p> </td> 
        </tr> 
        <tr> 
         <td> <p>PR</p> </td> 
         <td> <p>优先级</p> </td> 
        </tr> 
        <tr> 
         <td> <p>NI</p> </td> 
         <td> <p>nice值。负值表示高优先级，正值表示低优先级</p> </td> 
        </tr> 
        <tr> 
         <td> <p>P</p> </td> 
         <td> <p>最后使用的CPU，仅在多CPU环境下有意义</p> </td> 
        </tr> 
        <tr> 
         <td> <p>%CPU</p> </td> 
         <td> <p>上次更新到现在的CPU时间占用百分比</p> </td> 
        </tr> 
        <tr> 
         <td> <p>TIME</p> </td> 
         <td> <p>进程使用的CPU时间总计，单位秒</p> </td> 
        </tr> 
        <tr> 
         <td> <p>TIME+</p> </td> 
         <td> <p>进程使用的CPU时间总计，单位1/100秒</p> </td> 
        </tr> 
        <tr> 
         <td> <p>%MEM</p> </td> 
         <td> <p>进程使用的物理内存百分比</p> </td> 
        </tr> 
        <tr> 
         <td> <p>VIRT</p> </td> 
         <td> <p>进程使用的虚拟内存总量，单位kb。VIRT=SWAP+RES</p> </td> 
        </tr> 
        <tr> 
         <td> <p>SWAP</p> </td> 
         <td> <p>进程使用的虚拟内存中，被换出的大小，单位kb。</p> </td> 
        </tr> 
        <tr> 
         <td> <p>RES</p> </td> 
         <td> <p>进程使用的、未被换出的物理内存大小，单位kb。RES=CODE+DATA</p> </td> 
        </tr> 
        <tr> 
         <td> <p>CODE</p> </td> 
         <td> <p>可执行代码占用的物理内存大小，单位kb</p> </td> 
        </tr> 
        <tr> 
         <td> <p>DATA</p> </td> 
         <td> <p>可执行代码以外的部分(数据段+栈)占用的物理内存大小，单位kb</p> </td> 
        </tr> 
        <tr> 
         <td> <p>SHR</p> </td> 
         <td> <p>共享内存大小，单位kb</p> </td> 
        </tr> 
        <tr> 
         <td> <p>nFLT</p> </td> 
         <td> <p>页面错误次数</p> </td> 
        </tr> 
        <tr> 
         <td> <p>nDRT</p> </td> 
         <td> <p>最后一次写入到现在，被修改过的页面数。</p> </td> 
        </tr> 
        <tr> 
         <td> <p>S</p> </td> 
         <td> <p>进程状态。<br> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; D=不可中断的睡眠状态<br> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; R=运行<br> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; S=睡眠<br> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; T=跟踪/停止<br> &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Z=僵尸进程</p> </td> 
        </tr> 
        <tr> 
         <td> <p>COMMAND</p> </td> 
         <td> <p>命令名/命令行</p> </td> 
        </tr> 
        <tr> 
         <td> <p>WCHAN</p> </td> 
         <td> <p>若该进程在睡眠，则显示睡眠中的系统函数名</p> </td> 
        </tr> 
        <tr> 
         <td> <p>Flags</p> </td> 
         <td> <p>任务标志，参考 sched.h</p> </td> 
        </tr> 
       </tbody> 
      </table> 
      <p></p> 
      <p><span style="color:red">top </span><span style="color:red">的</span><span style="color:red">man </span><span style="color:red">命令解释如下：</span></p> 
      <p>&nbsp;&nbsp;&nbsp; Listed below are top's available fields.&nbsp; They are always associated with the&nbsp; letter&nbsp; shown,&nbsp; regardless&nbsp; of the position you may have established for them with the&nbsp; 'o' (Order fields) interactive command.Any field is selectable as the sort field, and you control whether they are&nbsp; sorted high-to-low&nbsp; or&nbsp; low-to-high.&nbsp;&nbsp; For&nbsp; additional&nbsp; information on sort provisions see&nbsp; topic 3c. TASK Area Commands.</p> 
      <p><span style="color:red">a: PID&nbsp; </span>--&nbsp; Process Id</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The task's unique process ID, which periodically wraps, though never&nbsp; restarting at zero.</p> 
      <p><span style="color:red">b: PPID&nbsp; </span>--&nbsp; Parent Process Pid</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The process ID of a task's parent.</p> 
      <p><span style="color:red">c: RUSER&nbsp; </span>--&nbsp; Real User Name</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The real user name of the task's owner.</p> 
      <p><span style="color:red">d: UID&nbsp; </span>--&nbsp; User Id</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The effective user ID of the task's owner.</p> 
      <p><span style="color:red">e: USER&nbsp; </span>--&nbsp; User Name</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The effective user name of the task's owner.</p> 
      <p><span style="color:red">f: GROUP&nbsp; </span>--&nbsp; Group Name</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The effective group name of the task's owner.</p> 
      <p><span style="color:red">g: TTY&nbsp; </span>--&nbsp; Controlling Tty</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The&nbsp; name of the controlling terminal.&nbsp; This is usually the device (serial port, pty, etc.) from which the process was started, and which it uses&nbsp; for&nbsp; input&nbsp; oroutput.&nbsp;&nbsp; However,&nbsp; a task need not be associated with a terminal, in which case you'll see '?' displayed.</p> 
      <p><span style="color:red">h: PR&nbsp; </span>--&nbsp; Priority</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The priority of the task.</p> 
      <p><span style="color:red">i: NI&nbsp; </span>--&nbsp; Nice value</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The nice value of the task.&nbsp;&nbsp; A&nbsp; negative&nbsp; nice&nbsp; value&nbsp; means&nbsp; higher&nbsp; priority, whereas&nbsp; a&nbsp; positive nice value means lower priority.&nbsp; Zero in this field simply means priority will not be adjusted in determining a task's dispatchability.</p> 
      <p><span style="color:red">j: P&nbsp; </span>--&nbsp; Last used CPU (SMP)</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; A number representing the last used processor.&nbsp; In a true SMP&nbsp; environment&nbsp; this will likely change frequently since the kernel intentionally uses weak affinity. Also, the very act of running top may break this weak affinity&nbsp; and&nbsp; cause&nbsp; more processes&nbsp; to change CPUs more often (because of the extra demand for cpu time).</p> 
      <p><span style="color:red">k: %CPU&nbsp; </span>--&nbsp; CPU usage</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The task's share of the elapsed CPU time since the last screen update, expressed as a percentage of total CPU time.&nbsp; In a true SMP environment, if 'Irix mode' is Off, top will operate in 'Solaris mode' where a task's cpu usage will be divided by&nbsp; the&nbsp; total&nbsp; number&nbsp; of&nbsp; CPUs.&nbsp;&nbsp; You toggle 'Irix/Solaris' modes with the 'I' interactive command.</p> 
      <p><span style="color:red">l: TIME&nbsp; </span>--&nbsp; CPU Time</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Total CPU time the task has used since it started.&nbsp; When&nbsp; 'Cumulative&nbsp; mode'&nbsp; is On,&nbsp; each&nbsp; process is listed with the cpu time that it and its dead children has used.&nbsp; You toggle 'Cumulative mode' with 'S', which is a command-line option and an interactive command.&nbsp; See the 'S' interactive command for additional information regarding this mode.</p> 
      <p><span style="color:red">m: TIME+&nbsp; </span>--&nbsp; CPU Time, hundredths</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The same as 'TIME', but reflecting more granularity through hundredths of a sec&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; ond.</p> 
      <p><span style="color:red">n: %MEM&nbsp; </span>--&nbsp; Memory usage (RES)</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; A task's currently used share of available physical memory.</p> 
      <p><span style="color:red">o: VIRT&nbsp; </span>--&nbsp; Virtual Image (kb)</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The total amount of virtual memory used by the task.&nbsp; It includes all code, data and shared libraries plus pages that have&nbsp; been&nbsp; swapped&nbsp; out.&nbsp; (Note:&nbsp; you&nbsp; can define&nbsp; the STATSIZE=1 environment variable and the VIRT will be calculated from the /proc/#/state VmSize field.)</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; VIRT = SWAP + RES.</p> 
      <p><span style="color:red">p: SWAP&nbsp; </span>--&nbsp; Swapped size (kb)</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The swapped out portion of a task's total virtual memory image.</p> 
      <p><span style="color:red">q: RES&nbsp; </span>--&nbsp; Resident size (kb)</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The non-swapped physical memory a task has used.</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; RES = CODE + DATA.</p> 
      <p><span style="color:red">r: CODE&nbsp; </span>--&nbsp; Code size (kb)</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The amount of physical memory devoted to executable&nbsp; code,&nbsp; also&nbsp; known&nbsp; as&nbsp; the'text resident set' size or TRS.</p> 
      <p><span style="color:red">s: DATA&nbsp; </span>--&nbsp; Data+Stack size (kb)</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The&nbsp; amount of physical memory devoted to other than executable code, also known the 'data resident set' size or DRS.</p> 
      <p><span style="color:red">t: SHR&nbsp; </span>--&nbsp; Shared Mem size (kb)</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The amount of shared memory used by a task.&nbsp;&nbsp; It&nbsp; simply&nbsp; reflects&nbsp; memory&nbsp; that could be potentially shared with other processes.</p> 
      <p><span style="color:red">u: nFLT&nbsp; </span>--&nbsp; Page Fault count</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The&nbsp; number&nbsp; of&nbsp; major&nbsp; page faults that have occurred for a task.&nbsp; A page fault occurs when a process attempts to read from or write to a virtual page&nbsp; that&nbsp; is not&nbsp; currently&nbsp; present&nbsp; in&nbsp; its address space.&nbsp; A major page fault is when disk access is involved in making that page available.</p> 
      <p><span style="color:red">v: nDRT&nbsp; </span>--&nbsp; Dirty Pages count</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The number of pages that have been modified since&nbsp; they&nbsp; were&nbsp; last&nbsp; written&nbsp; to disk.&nbsp;&nbsp; Dirty&nbsp; pages&nbsp; must&nbsp; be written to disk before the corresponding physical memory location can be used for some other virtual page.</p> 
      <p><span style="color:red">w: S&nbsp; </span>--&nbsp; Process Status</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The status of the task which can be one of:</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 'D' = uninterruptible sleep</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 'R' = running</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 'S' = sleeping</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 'T' = traced or stopped</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 'Z' = zombie</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Tasks shown as running should be more properly thought of as 'ready to run'&nbsp; --their&nbsp; task_struct is simply represented on the Linux run-queue.&nbsp; Even without a true SMP machine, you may see numerous tasks in this state&nbsp; depending&nbsp; on&nbsp; top's delay interval and nice value.</p> 
      <p><span style="color:red">x: Command&nbsp; </span>--&nbsp; Command line or Program name</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Display the command line used to start a task or the name of the associated program.&nbsp; You toggle between command line and name with 'c', which is both&nbsp; a&nbsp; command-line option and an interactive command. When&nbsp; you've&nbsp; chosen&nbsp; to display command lines, processes without a command line (like kernel threads) will be shown with only the program name&nbsp; in&nbsp; parentheses, as in this example:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; ( mdrecoveryd ) Either&nbsp; form&nbsp; of&nbsp; display is subject to potential truncation if it's too long to fit in this field's&nbsp; current&nbsp; width.&nbsp;&nbsp; That&nbsp; width&nbsp; depends&nbsp; upon&nbsp; other&nbsp; fields&nbsp; selected, their order and the current screen width.</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Note: The 'Command' field/column is unique, in that it is not fixed-width.&nbsp; When displayed, this column will be allocated all remaining screen width (up&nbsp; to&nbsp; the maximum&nbsp; 512&nbsp; characters)&nbsp; to&nbsp; provide for the potential growth of program names into command lines.</p> 
      <p><span style="color:red">y: WCHAN&nbsp; </span>--&nbsp; Sleeping in Function</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Depending on the availability of the kernel link map ('System.map'), this&nbsp; field will&nbsp; show&nbsp; the&nbsp; name or the address of the kernel function in which the task is currently sleeping.&nbsp; Running tasks will display a dash ('-') in this column.</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Note: By displaying this field, top's own working set will be increased by&nbsp; over 700Kb.&nbsp;&nbsp; Your&nbsp; only&nbsp; means of reducing that overhead will be to stop and restart&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; top.</p> 
      <p><span style="color:red">z: Flags&nbsp; </span>--&nbsp; Task Flags</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; This column represents the task's current scheduling flags which&nbsp; are&nbsp; expressed in&nbsp; hexadecimal&nbsp; notation and with zeros suppressed.&nbsp; These flags are officially documented in &lt;linux/sched.h&gt;.&nbsp; Less formal documentation can also be&nbsp; found&nbsp; on the 'Fields select' and 'Order fields' screens.</p> 
      <p></p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <span style="color:red">默认情况下仅显示比较重要的</span><span style="color:red">&nbsp; PID</span><span style="color:red">、</span><span style="color:red">USER</span><span style="color:red">、</span><span style="color:red">PR</span><span style="color:red">、</span><span style="color:red">NI</span><span style="color:red">、</span><span style="color:red">VIRT</span><span style="color:red">、</span><span style="color:red">RES</span><span style="color:red">、</span><span style="color:red">SHR</span><span style="color:red">、</span><span style="color:red">S</span><span style="color:red">、</span><span style="color:red">%CPU</span><span style="color:red">、</span><span style="color:red">%MEM</span><span style="color:red">、</span><span style="color:red">TIME+</span><span style="color:red">、</span><span style="color:red">COMMAND&nbsp; </span><span style="color:red">列。</span></p> 
      <p></p> 
      <p><span style="color:red">2.1 </span><span style="color:red">用快捷键更改显示内容。</span><br> <span style="color:red">（</span><span style="color:red">1</span><span style="color:red">）更改显示内容通过</span><span style="color:red"> f</span><span style="color:red">键可以选择显示的内容。</span></p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 按 f 键之后会显示列的列表，按 a-z&nbsp; 即可显示或隐藏对应的列，最后按回车键确定。</p> 
      <p></p> 
      <p><span style="color:red">（</span><span style="color:red">2</span><span style="color:red">）按</span><span style="color:red">o</span><span style="color:red">键可以改变列的显示顺序。</span></p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 按小写的 a-z 可以将相应的列向右移动，而大写的 A-Z&nbsp; 可以将相应的列向左移动。最后按回车键确定。</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 按大写的 F 或 O 键，然后按 a-z 可以将进程按照相应的列进行排序。而大写的&nbsp; R 键可以将当前的排序倒转。 </p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 设置完按回车返回界面。</p> 
      <p></p> 
      <p><span style="color:red">三</span><span style="color:red">.&nbsp; </span><span style="color:red">命令使用</span></p> 
      <p>详细内容可以参考MAN 帮助文档。这里列举部分内容：</p> 
      <p><span style="color:red">命令格式：</span></p> 
      <p>top [-] [d] [p] [q] [c] [C] [S]&nbsp;&nbsp;&nbsp; [n] </p> 
      <p></p> 
      <p><span style="color:red">参数说明：</span></p> 
      <p>d：&nbsp; 指定每两次屏幕信息刷新之间的时间间隔。当然用户可以使用s交互命令来改变之。</p> 
      <p>p：&nbsp; 通过指定监控进程ID来仅仅监控某个进程的状态。</p> 
      <p>q：该选项将使top没有任何延迟的进行刷新。如果调用程序有超级用户权限，那么top将以尽可能高的优先级运行。</p> 
      <p>S： 指定累计模式</p> 
      <p>s ： 使top命令在安全模式中运行。这将去除交互命令所带来的潜在危险。</p> 
      <p>i：&nbsp; 使top不显示任何闲置或者僵死进程。</p> 
      <p>c：&nbsp; 显示整个命令行而不只是显示命令名</p> 
      <p></p> 
      <p></p> 
      <p><span style="color:red">在</span><span style="color:red">top</span><span style="color:red">命令的显示窗口，我们还可以输入以下字母，进行一些交互：</span></p> 
      <p></p> 
      <p>帮助文档如下：</p> 
      <p>Help for Interactive Commands - procps version 3.2.7</p> 
      <p>Window 1:Def: Cumulative mode Off.&nbsp; System: Delay 4.0 secs; Secure mode Off.</p> 
      <p></p> 
      <p>&nbsp; Z,B&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Global: 'Z' change color mappings; 'B' disable/enable bold</p> 
      <p>&nbsp; l,t,m&nbsp;&nbsp;&nbsp;&nbsp; Toggle Summaries: 'l' load avg; 't' task/cpu stats; 'm' mem info</p> 
      <p>&nbsp; 1,I&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Toggle SMP view: '1' single/separate states; 'I' Irix/Solaris mode</p> 
      <p></p> 
      <p>&nbsp; f,o&nbsp;&nbsp;&nbsp;&nbsp; . Fields/Columns: 'f' add or remove; 'o' change display order</p> 
      <p>&nbsp; F or O&nbsp; . Select sort field</p> 
      <p>&nbsp; &lt;,&gt;&nbsp;&nbsp;&nbsp;&nbsp; . Move sort field: '&lt;' next col left; '&gt;' next col right</p> 
      <p>&nbsp; R,H&nbsp;&nbsp;&nbsp;&nbsp; . Toggle: 'R' normal/reverse sort; 'H' show threads</p> 
      <p>&nbsp; c,i,S&nbsp;&nbsp; . Toggle: 'c' cmd name/line; 'i' idle tasks; 'S' cumulative time</p> 
      <p>&nbsp; x,y&nbsp;&nbsp;&nbsp;&nbsp; . Toggle highlights: 'x' sort field; 'y' running tasks</p> 
      <p>&nbsp; z,b&nbsp;&nbsp;&nbsp;&nbsp; . Toggle: 'z' color/mono; 'b' bold/reverse (only if 'x' or 'y')</p> 
      <p>&nbsp; u&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; . Show specific user only</p> 
      <p>&nbsp; n or #&nbsp; . Set maximum tasks displayed</p> 
      <p></p> 
      <p>&nbsp; k,r&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Manipulate tasks: 'k' kill; 'r' renice</p> 
      <p>&nbsp; d or s&nbsp;&nbsp;&nbsp; Set update interval</p> 
      <p>&nbsp; W&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Write configuration file</p> 
      <p>&nbsp; q&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Quit</p> 
      <p>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; ( commands shown with '.' require a visible task display window ) </p> 
      <p>Press 'h' or '?' for help with Windows,</p> 
      <p></p> 
      <p></p> 
      <p><span style="color:red">h</span><span style="color:red">或者</span><span style="color:red">?&nbsp; : </span>显示帮助画面，给出一些简短的命令总结说明。</p> 
      <p><span style="color:red">k&nbsp; </span><span style="color:red">：</span>终止一个进程。系统将提示用户输入需要终止的进程PID，以及需要发送给该进程什么样的信号。一般的终止进程可以使用15信号；如果不能正常结束那就使用信号9强制结束该进程。<span style="color:red">默认值是信号</span><span style="color:red">15</span><span style="color:red">。</span>在安全模式中此命令被屏蔽。</p> 
      <p><span style="color:red">i</span><span style="color:red">：</span>忽略闲置和僵死进程。这是一个开关式命令。</p> 
      <p><span style="color:red">q</span><span style="color:red">：</span>&nbsp; 退出程序。</p> 
      <p><span style="color:red">r</span><span style="color:red">：</span>&nbsp; 重新安排一个进程的优先级别。系统提示用户输入需要改变的进程PID以及需要设置的进程优先级值。输入一个正值将使优先级降低，反之则可以使该进程拥有更高的优先权。默认值是10。</p> 
      <p><span style="color:red">S</span><span style="color:red">：</span>切换到累计模式。</p> 
      <p><span style="color:red">s : </span>改变两次刷新之间的延迟时间。系统将提示用户输入新的时间，单位为s。如果有小数，就换算成ms。输入0值则系统将不断刷新，<span style="color:red">默认值是</span><span style="color:red">5 s</span>。需要注意的是如果设置太小的时间，很可能会引起不断刷新，从而根本来不及看清显示的情况，而且系统负载也会大大增加。</p> 
      <p><span style="color:red">f</span><span style="color:red">或者</span><span style="color:red">F </span>:从当前显示中添加或者删除项目。</p> 
      <p><span style="color:red">o</span><span style="color:red">或者</span><span style="color:red">O&nbsp; :</span>改变显示项目的顺序。</p> 
      <p><span style="color:red">l: </span>切换显示平均负载和启动时间信息。<span style="color:red">即显示影藏第一行</span></p> 
      <p><span style="color:red">m</span><span style="color:red">：</span> 切换显示内存信息。<span style="color:red">即显示影藏内存行</span></p> 
      <p><span style="color:red">t </span><span style="color:red">：</span> 切换显示进程和CPU状态信息。<span style="color:red">即显示影藏</span><span style="color:red">CPU</span><span style="color:red">行</span></p> 
      <p><span style="color:red">c</span><span style="color:red">：</span><span style="color:red">切换显示命令名称和完整命令行。</span><span style="color:red">显示完整的命令。</span><span style="color:red">这个功能很有用。</span></p> 
      <p><span style="color:red">M </span><span style="color:red">：</span> 根据驻留内存大小进行排序。</p> 
      <p><span style="color:red">P</span><span style="color:red">：</span>根据CPU使用百分比大小进行排序。</p> 
      <p><span style="color:red">T</span><span style="color:red">：</span>根据时间/累计时间进行排序。</p> 
      <p><span style="color:red">W</span><span style="color:red">：</span>&nbsp; 将当前设置写入~/.toprc文件中。这是写top配置文件的推荐方法。</p> 
     </div> 
    </div> </td> 
  </tr> 
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</table>

[Link 1]: http://www.cnblogs.com/allen8807/archive/2010/11/10/1874001.html#