电源管理在 17.10 中只有“什么都不做”的选项来应对电池严重不足的情况
Que*_*ner 10 power-management 17.10
我在华硕笔记本电脑上使用 Ubuntu 17.10 和 Gnome。
在“电源设置”界面的“电源”选项卡下，底部有一个选项可以设置电池电量严重不足时的操作。
但是，当我单击下拉菜单来设置该选项时，它只提供一个选项，即“什么都不做”：
目前，我的笔记本电脑的电池电量将降至 0 或接近 0，然后在没有警告的情况下关闭，也无法关闭程序并正常关闭。
我想在电池电量为 10% 时收到警告，并希望在关闭计算机之前有一些时间手动保存和关闭程序。我如何实现这一目标？
编辑：这是我的/etc/UPower/UPower.conf文件的内容：
# Only the system vendor should modify this file, ordinary users
# should not have to change anything.
[UPower]
# Enable the Watts Up Pro device.
#
# The Watts Up Pro contains a generic FTDI USB device without a specific
# vendor and product ID. When we probe for WUP devices, we can cause
# the user to get a perplexing "Device or resource busy" error when
# attempting to use their non-WUP device.
#
# The generic FTDI device is known to also be used on:
#
# - Sparkfun FT232 breakout board
# - Parallax Propeller
#
# default=false
EnableWattsUpPro=false
# Don't poll the kernel for battery level changes.
#
# Some hardware will send us battery level changes through
# events, rather than us having to poll for it. This option
# allows disabling polling for hardware that sends out events.
#
# default=false
NoPollBatteries=false
# Do we ignore the lid state
#
# Some laptops are broken. The lid state is either inverted, or stuck
# on or off. We can't do much to fix these problems, but this is a way
# for users to make the laptop panel vanish, a state that might be used
# by a couple of user-space daemons. On Linux systems, see also
# logind.conf(5).
#
# default=false
IgnoreLid=false
# Policy for warnings and action based on battery levels
#
# Whether battery percentage based policy should be used. The default
# is to use the time left, change to true to use the percentage, which
# should work around broken firmwares. It is also more reliable than
# the time left (frantically saving all your files is going to use more
# battery than letting it rest for example).
# default=true
UsePercentageForPolicy=true
# When UsePercentageForPolicy is true, the levels at which UPower will
# consider the battery low, critical, or take action for the critical
# battery level.
#
# This will also be used for batteries which don't have time information
# such as that of peripherals.
#
# If any value is invalid, or not in descending order, the defaults
# will be used.
#
# Defaults:
# PercentageLow=10
# PercentageCritical=3
# PercentageAction=2
PercentageLow=10
PercentageCritical=3
PercentageAction=2
# When UsePercentageForPolicy is false, the time remaining at which UPower
# will consider the battery low, critical, or take action for the critical
# battery level.
#
# If any value is invalid, or not in descending order, the defaults
# will be used.
#
# Defaults:
# TimeLow=1200
# TimeCritical=300
# TimeAction=120
TimeLow=1200
TimeCritical=300
TimeAction=120
# The action to take when "TimeAction" or "PercentageAction" above has been
# reached for the batteries (UPS or laptop batteries) supplying the computer
#
# Possible values are:
# PowerOff
# Hibernate
# HybridSleep
#
# If HybridSleep isn't available, Hibernate will be used
# If Hibernate isn't available, PowerOff will be used
CriticalPowerAction=HybridSleep
第 1 步：检查 gsettings
您可以在终端中检查两个选项：
$ gsettings get org.gnome.settings-daemon.plugins.power critical-battery-action
'suspend'
$ gsettings get org.gnome.settings-daemon.plugins.power percentage-low
'10'
然后更改它们使用：
$ gsettings set org.gnome.settings-daemon.plugins.power critical-battery-action suspend
$ gsettings set org.gnome.settings-daemon.plugins.power percentage-low 10
注意在我的系统上它们很好，所以为了举例，我把它们改回原来的样子。
第 2 步：检查 upower
Gnome 电源管理upower用于完成繁重的工作。为确保它正常运行并收集电池统计信息，请使用：
$ upower -d
Device: /org/freedesktop/UPower/devices/line_power_ACAD
native-path: ACAD
power supply: yes
updated: Sun 18 Mar 2018 02:28:25 PM MDT (135878 seconds ago)
has history: no
has statistics: no
line-power
warning-level: none
online: yes
icon-name: 'ac-adapter-symbolic'
Device: /org/freedesktop/UPower/devices/battery_BAT1
native-path: BAT1
vendor: COMPAL
model: PABAS0241231
serial: 41167
power supply: yes
updated: Tue 20 Mar 2018 04:12:10 AM MDT (53 seconds ago)
has history: yes
has statistics: yes
battery
present: yes
rechargeable: yes
state: charging
warning-level: none
energy: 48.2544 Wh
energy-empty: 0 Wh
energy-full: 93.3552 Wh
energy-full-design: 96.48 Wh
energy-rate: 0.0044914 W
voltage: 14.76 V
percentage: 51%
capacity: 96.7612%
technology: lithium-ion
icon-name: 'battery-good-charging-symbolic'
Device: /org/freedesktop/UPower/devices/mouse_0003o046Do101Ax0008
native-path: /sys/devices/pci0000:00/0000:00:14.0/usb1/1-2/1-2:1.2/0003:046D:C52B.0003/0003:046D:101A.0008
vendor: Logitech, Inc.
model: Performance MX
serial: E6CE4571
power supply: no
updated: Tue 20 Mar 2018 04:12:09 AM MDT (54 seconds ago)
has history: yes
has statistics: no
mouse
present: yes
rechargeable: yes
state: discharging
warning-level: none
percentage: 55%
icon-name: 'battery-good-symbolic'
Device: /org/freedesktop/UPower/devices/keyboard_0003o046Do2010x0009
native-path: /sys/devices/pci0000:00/0000:00:14.0/usb1/1-2/1-2:1.2/0003:046D:C52B.0003/0003:046D:2010.0009
vendor: Logitech, Inc.
model: K800
serial: 6DB54BFE
power supply: no
updated: Tue 20 Mar 2018 04:12:09 AM MDT (54 seconds ago)
has history: yes
has statistics: no
keyboard
present: yes
rechargeable: yes
state: discharging
warning-level: none
percentage: 90%
icon-name: 'battery-full-symbolic'
Device: /org/freedesktop/UPower/devices/ups_hiddev3
native-path: /sys/devices/pci0000:00/0000:00:14.0/usb1/1-1/1-1.4/1-1.4.4/1-1.4.4:1.0/usbmisc/hiddev3
vendor: CPS
model: CP550HGa
serial: BFBB104#BI1.g
power supply: yes
updated: Tue 20 Mar 2018 04:12:51 AM MDT (12 seconds ago)
has history: yes
has statistics: yes
ups
present: yes
state: fully-charged
warning-level: none
time to empty: 37.5 minutes
percentage: 100%
icon-name: 'battery-full-charged-symbolic'
Device: /org/freedesktop/UPower/devices/DisplayDevice
power supply: yes
updated: Tue 20 Mar 2018 04:10:14 AM MDT (169 seconds ago)
has history: no
has statistics: no
ups
present: yes
state: fully-charged
warning-level: none
time to empty: 37.5 minutes
percentage: 100%
icon-name: 'battery-full-charged-symbolic'
Daemon:
daemon-version: 0.99.4
on-battery: no
lid-is-closed: no
lid-is-present: yes
critical-action: HybridSleep
首先在笔记本电脑插入电源时运行此命令。然后拔下笔记本电脑并在一段时间后运行该命令，确保电池剩余时间适当减少。
最后一步 - 低级休眠
这是在用尽所有其他步骤后将采取的最后一步。此步骤不需要 Ubuntu 或 Unity 或 Gnomegsettings或upower. 它只需要systemd,udev并且cron几乎所有带有或不带有 GUI（桌面）的 Linux 发行版都内置了。
电池电量低时休眠
如果您的电池在充电udev（放电）1% 时发送事件，您可以使用此udev规则在电池电量严重不足时自动休眠系统，从而防止所有未保存的工作丢失。
注意：并非所有电池都报告放电事件。通过udevadm monitor --property在使用电池时运行来进行测试，看看是否报告了任何事件。您应该等待至少 1% 的跌幅。如果没有事件报告并且/sys/class/power_supply/BAT0/alarm非零，则电池可能会在BAT0/energy_now低于警报值时触发事件，并且udev只要百分比数学计算成功，该规则就会起作用。默认情况下，某些笔记本电脑在 BIOS 中具有禁用此功能的选项。
$ cat /etc/udev/rules.d/99-lowbat.rules
# Suspend the system when battery level drops to 5% or lower
SUBSYSTEM=="power_supply", ATTR{status}=="Discharging", ATTR{capacity}=="[0-5]", RUN+="/usr/bin/systemctl hibernate"
只要设置了条件，就会重复此规则。因此，当电池电量不足时从休眠状态恢复时，计算机将直接休眠。有些笔记本电脑在超过一定的电池电量后无法启动，因此可以相应地调整规则。
电池可以跳转到一个较低的值，而不是连续排出的，所以一udev字符串匹配图案的所有能力0通过5被使用。
可以添加其他规则以根据电源状态和/或容量执行不同的操作。
如果您的系统没有或缺少 ACPI 事件，请使用cron以下脚本：
#!/bin/sh
acpi -b | awk -F'[,:%]' '{print $2, $3}' | {
read -r status capacity
if [ "$status" = Discharging -a "$capacity" -lt 5 ]; then
logger "Critical battery threshold"
systemctl hibernate
fi
}
测试事件
测试udev规则的一种方法是让它们在运行时创建一个文件。例如：
$ cat /etc/udev/rules.d/98-discharging.rules
SUBSYSTEM=="power_supply", ATTR{status}=="Discharging", RUN+="/usr/bin/touch /home/example/discharging"
这会在/home/example/discharging拔下笔记本电脑充电器时创建一个文件。您可以通过拔掉笔记本电脑并查找此文件来测试规则是否有效。有关更高级的udev规则测试，请参阅加载前的 Udev#Testing 规则。
概括
在第 2 步和“最后一步”之间还有更多的步骤要发布，但这些将随着 OP 在测试后揭示更多细节而发布。同时，“最后一步”应该减少更多的中途答案，例如简单地报告剩余百分比。