Linux 2.6 内核中的最新电源管理技术综述
通过以上的介绍,大家对如何使用 cpufreq 通过 sysfs 提供的用户接口已经有了大致的了解,但是对于绝大部分用户而言,逐一操作这些文件既费力又耗时。因此 Dominik 等人开发了cpufrequtils 工具包[2],为用户提供了更加简便的对内核cpufreq 子系统的操作接口。通过 cpufreq-info 的输出,读者可以很清楚的看到刚刚在上面介绍过的/sys/devices/system/cpu/cpuX/cpufreq/ 目录下各个文件的内容。
$ cpufreq-info
cpufrequtils 002: cpufreq-info (C) Dominik Brodowski
2004-2006
Report errors and bugs to linux@brodo.de, please.
analyzing CPU 0:
driver: acpi-cpufreq
CPUs which need to switch frequency at the same time:
0 1
hardware limits: 1000 MHz - 1.67 GHz
available frequency steps: 1.67 GHz, 1.33 GHz, 1000
MHz
available cpufreq governors: userspace, conservative,
ondemand, powersave, performance
current policy: frequency should be within 1000 MHz
and 1.67 GHz.
The governor "ondemand" may decide which
speed to use
within this range.
current CPU frequency is 1000 MHz.
analyzing CPU 1:
driver: acpi-cpufreq
CPUs which need to switch frequency at the same time:
0 1
hardware limits: 1000 MHz - 1.67 GHz
availablehttp://www.ruishen.net.cn/电感器 frequency steps: 1.67 GHz, 1.33 GHz, 1000
MHz
available cpufreq governors: userspace, conservative,