> For the complete documentation index, see [llms.txt](https://slackwarecn.gitbook.io/slackbook_cn/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://slackwarecn.gitbook.io/slackbook_cn/chapter_06/top.md).

# top

到目前为止，我们学习了如何查看当前活跃的进程，但是假如我们想监视系统一段时间呢？`top` 按照一定顺序显示你的系统上的进程，包括它们的相关信息。默认情况下，进程按照他们的 CPU 占用率排序且每 3 秒更新一次。

```
darkstar:~$ top
top - 16:44:15 up 26 days,  5:53,  5 users,  load average: 0.08, 0.03, 0.03
Tasks: 122 total,   1 running, 119 sleeping,   0 stopped,   2 zombie
Cpu(s):  3.4%us,  0.7%sy,  0.0%ni, 95.5%id,  0.1%wa,  0.0%hi,  0.2%si, 0.0%st
Mem:   3058360k total,  2853780k used,   204580k free,   154956k buffers
Swap:        0k total,        0k used,        0k free,  2082652k cached

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
    1 root      20   0  3928  632  544 S    0  0.0   0:00.99 init
    2 root      15  -5     0    0    0 S    0  0.0   0:00.00 kthreadd
    3 root      RT  -5     0    0    0 S    0  0.0   0:00.82 migration/0
    4 root      15  -5     0    0    0 S    0  0.0   0:00.01 ksoftirqd/0
    7 root      15  -5     0    0    0 S    0  0.0   0:11.22 events/0
    9 root      15  -5     0    0    0 S    0  0.0   0:01.19 work_on_cpu/0
   11 root      15  -5     0    0    0 S    0  0.0   0:00.01 khelper
  102 root      15  -5     0    0    0 S    0  0.0   0:02.04 kblockd/0
  105 root      15  -5     0    0    0 S    0  0.0   1:20.08 kacpid
  106 root      15  -5     0    0    0 S    0  0.0   0:01.92 kacpi_notify
  175 root      15  -5     0    0    0 S    0  0.0   0:00.00 ata/0
  177 root      15  -5     0    0    0 S    0  0.0   0:00.00 ata_aux
  178 root      15  -5     0    0    0 S    0  0.0   0:00.00 ksuspend_usbd
  184 root      15  -5     0    0    0 S    0  0.0   0:00.02 khubd
  187 root      15  -5     0    0    0 S    0  0.0   0:00.00 kseriod
  242 root      20   0     0    0    0 S    0  0.0   0:03.37 pdflush
  243 root      15  -5     0    0    0 S    0  0.0   0:02.65 kswapd0
```

man 页面包含了如何与 `top` 进行交互的详细帮助，比如改变延迟时间，进程显示的顺序，甚至是如何在 `top` 里立刻结束进程。