GNU/Linux 电源管理 ： PowerTOP

▲ PowerTOP 的起始画面。

开始前请先安装 powertop。

# Debian, Ubuntu
$ sudo aptitude install powertop

# CentOS, RHEL, Fedora
$ sudo yum install powertop

# Arch Linux
$ sudo pacman -S powertop

请使用 Tab, Shift + Tab 或方向键 ←, → 切换至 Tunables 分页 ¹，并使用 ↑, ↓ 上下移动，于欲调校的项目按下 Enter 进行调校，当所有状态显示为 Good 后即可按下 q 离开。

▲ 调校前的 Tunables。

▲ 调校后的 Tunables。

PowerTOP 本身并无储存功能，但我们可以借由 powertop '--html' 产生的报告来调校系统，甚至于开机时载入这些设定。

$ sudo powertop --html
Loaded 58 prior measurements
Cannot load from file /var/cache/powertop/saved_parameters.powertop
Preparing to take measurements
Measuring 1 time(s) for 20 seconds each
PowerTOP outputing using base filename powertop-20130915-231821.html

▲ 此报告将依个人环境而有所不同，其各项目的详细说明可参考 Power saving - ArchWiki 一文。

接著将调校的指令贴到一个 shell script 打包起来。

$ sudo vi /usr/local/bin/powersave
#!/bin/bash
# PowerTop conifg for ThinkPad T410 on Debian Wheezy.

# Wireless Power Saving for interface wlan0
iw dev wlan0 set power_save off

# Enable SATA link power management for /dev/sda
echo 'min_power' > '/sys/class/scsi_host/host0/link_power_management_policy';

# NMI watchdog should be turned off
echo '0' > '/proc/sys/kernel/nmi_watchdog';

# VM writeback timeout
echo '1500' > '/proc/sys/vm/dirty_writeback_centisecs';

# Enable Audio codec power management    
echo '1' > '/sys/module/snd_hda_intel/parameters/power_save';

# Autosuspend for USB device Biometric Coprocessor [UPEK]    
echo 'auto' > '/sys/bus/usb/devices/1-1.3/power/control';

# Runtime PM for PCI Device Ricoh Co Ltd MMC/SD Host Controller
echo 'auto' > '/sys/bus/pci/devices/0000:0d:00.0/power/control';

# Runtime PM for PCI Device Intel Corporation Core Processor PCI Express x16 Root Port    
echo 'auto' > '/sys/bus/pci/devices/0000:00:01.0/power/control';

# Runtime PM for PCI Device Intel Corporation 82577LM Gigabit Network Connection    
echo 'auto' > '/sys/bus/pci/devices/0000:00:19.0/power/control';

# Runtime PM for PCI Device Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller    
echo 'auto' > '/sys/bus/pci/devices/0000:00:1a.0/power/control';

# Runtime PM for PCI Device Intel Corporation 5 Series/3400 Series Chipset High Definition Audio    
echo 'auto' > '/sys/bus/pci/devices/0000:00:1b.0/power/control';

# Runtime PM for PCI Device Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 4    
echo 'auto' > '/sys/bus/pci/devices/0000:00:1c.3/power/control';

# Runtime PM for PCI Device Ricoh Co Ltd R5C832 PCIe IEEE 1394 Controller    
echo 'auto' > '/sys/bus/pci/devices/0000:0d:00.3/power/control';

# Runtime PM for PCI Device Intel Corporation Centrino Wireless-N 1000 [Condor Peak]    
echo 'auto' > '/sys/bus/pci/devices/0000:03:00.0/power/control';

# Runtime PM for PCI Device Intel Corporation 5 Series/3400 Series Chipset SMBus Controller    
echo 'auto' > '/sys/bus/pci/devices/0000:00:1f.3/power/control';

# Runtime PM for PCI Device Intel Corporation 5 Series/3400 Series Chipset Thermal Subsystem    
echo 'auto' > '/sys/bus/pci/devices/0000:00:1f.6/power/control';

# Runtime PM for PCI Device Intel Corporation 5 Series/3400 Series Chipset 6 port SATA AHCI Controller    
echo 'auto' > '/sys/bus/pci/devices/0000:00:1f.2/power/control';

# Runtime PM for PCI Device NVIDIA Corporation GT218 [NVS 3100M]    
echo 'auto' > '/sys/bus/pci/devices/0000:01:00.0/power/control';

# Runtime PM for PCI Device Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller    
echo 'auto' > '/sys/bus/pci/devices/0000:00:1d.0/power/control';

# Runtime PM for PCI Device Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 1
echo 'auto' > '/sys/bus/pci/devices/0000:00:1c.0/power/control';

# Runtime PM for PCI Device Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 5    
echo 'auto' > '/sys/bus/pci/devices/0000:00:1c.4/power/control';

# Runtime PM for PCI Device NVIDIA Corporation High Definition Audio Controller    
echo 'auto' > '/sys/bus/pci/devices/0000:01:00.1/power/control';

# Runtime PM for PCI Device Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 2    
echo 'auto' > '/sys/bus/pci/devices/0000:00:1c.1/power/control';

# Wake-on-lan status for device eth0
#ethtool -s eth0 wol d;

给予执行权限。

$ sudo chmod +x /usr/local/bin/powersave

因调校指令皆需管理者权限才可执行，若想省下打密码的功夫可参考 Firestarter 开机不用再次输入密码 一文修改。

$ sudo visudo
......
jonny   ALL= NOPASSWD:/usr/local/bin/powersave

现在开机时只需使用 sudo powersave 即可手动切换至省电模式。

若想加入开机自动启动可以参考 安装 indicator-virtualbox on Ubuntu 12.04 | 4. 加入开机自动启动 一文或使用较进阶的 udev 及 sysctl。

※ 注：请依个人需求自行调整，若造成系统不稳还请自行斟酌。

资料来源

• PowerTOP - Wikipedia
• Powertop - ArchWiki
• 2.2. PowerTOP - Red Hat Customer Portal
• 冷静: Powertop

¹. 感谢 theJian 回报，powertop v2.5 之后切换 Tunables 分页的功能键已从方向键 ←, → 改为 Tab 和 Shift + Tab。 ↩