xfce4-power-manager version 0.6.0
Copyright © 2008 Ali Abdallah
Table of Contents
To launch the Power Manager you need to run the following command xfce4-power-manager -r which you can do from the xfce run
command by pressing on ALT-F2, or by going to the Xfce settings manager and clicking on the Power Manager item -
a popup will be displayed to run the power manger if it is not already running.
Once the power manager is launched for the first time, it will place an autostart desktop file in your .config/autostart
in order to be able to be launched automatically each time you log into your Xfce desktop.
Almost all the xfce4-power-manager items are configurable from the configuration window, laptop users can set up
a power profile for two different modes “on battery power” and “on ac power”, desktop users still can change
DPMS settings and CPU frequency.
The settings dialog differs from one system to another depending on the computer (PC,laptop,...) and on the available manageabale interfaces.
In this section we will describe the possible configuration for the power manager.
Here you can select the configuration of the system tray icon, enable/disable cpu frequency and DPMS controls. For example, you would need to disable DPMS control when watching a movie.
The linux governors found in the system are listed as radio buttons. If the acpi_cpufreq module is not loaded in the kernel or the cpu itself does not support frequency changes these options might not show.
Here is a brief descritption on linux cpu governors
- Best performance:
Set CPU to its maximum frequency: consume more power, and it is not ideal when running on battery.
- Best power savings:
Set the CPU to its minimum frequency: ideal when running on battery power.
- Ondemand performance:
What you want is what you get: set the CPU depending on the current usage.
- Good power savings:
Same as Ondemand but differs in behaviour in that it gracefully increases and decreases the CPU speed rather than jumping to max speed the moment there is any load on the CPU.
NOTE:In xfce4-power-manager version 0.6.0 only Linux is supported for changing the CPU frequency.
The user can select the his critical battery percentage, usually this is for a laptop or UPS battery, this option is important for a broken battery for example, which lasts only 5 minutes when it is 10% charged.
The user can define an action to be taken by the power manager in case the battery that is giving the main power for the computer reaches a critical charge level.
The battery notification is a way to notify the user when the battery state changes ( ex: battery charge is full )
DPMS is an old X extension that allows standby/suspend/turn off options of the monitor, usually the timeouts have to be consecutive, so standby timeout is less than suspend timeout and so on, but any option can always be disabled.
For laptop users, clicking on the checkbox allows the power manager to reduce the screen luminosity when it detects that system in running on battery power and increase it again when the system is running on AC power.
The "system tray" is an application running on a given X screen that can display small icons provided by running applications. In Xfce, it is a panel plugin that catches the icon and resizes it to the size of the panel, if you don't have this plugin added to the panel you will not see any tray icon, for example pidgin places an icon in the system tray as well as many other applications.
xfce4-power-manager uses GtkStatusIcon to display the different kinds of batteries found in the system.
To notify the user about the status of the battery, serious errors occured, the notification daemon is used to display such messages.
- Q: Why the icons look very similar to the icon of gnome power manager?
A: No, they are not similar, they are the same, just there is no point of re-drawing icons, gnome power manager icons are good enough. Not all of them are used.
- Q: What is the difference between suspend and hibernate?
A: Suspend is a power save feature. When suspending, the computer is still using power, since the running applications are kept in the memory, but it is the lowest power level that the computer can use. While Hibernate saves the system state on the hard drive and turns off the power, when you start up your computer again those data will be loaded and the system back up.
- Q: Why the options of suspend/hibernate are not there or I can not select them?
A: Many possible reasons, for example your kernel is not compiled with suspend/hibernate options. Another possible reason is the fact that you are not allowed to use them.
- Q: How the power manager actually suspend or hibernate my system?
A: The power manager checks if the user is allowed to use power management service, then send a D-Bus message to HAL asking to suspend/hibernate, usually the methods to suspend or hibernate used by HAL are scripts located in /usr/lib/hal/scripts/YourOs.
- Q: If the power manager puts the computer in hibernate because my battery charge is critical what will happen if I turn it on again without plugging my adapter?
A: Nothing actually, the power manager had taken the action defined by the user already. In the best cases, it will display a warning popup with different options.
- Q: I select the option of the LCD brightness control but I do not see the brightness changing when I switch from AC adapter to battery power?
A: Your kernel does not have the right driver, or the driver is not loaded.
This power manager was written following the philosophy of Xfce, having light weight application that does what the user is expecting from it.
To report a bug or make a suggestion regarding this application or this manual, use the bug tracking system at http://bugzilla.xfce.org/.
If you have questions about the use or installation of this package, please ask on the xfce mailing list. Development discussion takes place on the xfce4-dev mailing list or on xfce4-goodies-dev mailing list.
This program is distributed under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.