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 you can do from the xfce run
command by pressing ALT-F2, or you go to the Xfce settings manager and you click on the Power Manager item
, a popup should be displayed only if the power manager isn't already running to ask you if you want to.
Once the power manager is launched for the first time, it'll place a autostart desktop file in your .config/autostart
so like that it gets launched automatically second 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 depends 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, typical reason to disable DPMS control for example if you are watching a movie.
The linux governors found in the system are listed for choice as a radio buttons, if the acpi_cpufreq module is not loaded in the kernel or the cpu itself doesn't support changes in it's frequency these options might not be shown.
Here's a brief descritption on linux cpu governors
- Performance:
Set the CPU to it's maximum frequency. will consume more power, and it's not ideal when running on battery.
- Powersave:
Set the CPU to it's minimum frequency, ideal when running on battery power.
- Userspace:
In this governor, allows the user, or any userspace program running with UID "root", to set the CPU to a specific frequency.
- Ondemand:
What you want is what you get. sets the CPU depending on the current usage.
- Conservative:
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 percentage of the battery to be considered as critical, usually this is for a laptop or UPS battery, this option is important as for a broken battery for example, the battery when it is 10% charged can last 5 minutes, so the user can increase the level at wish the battery charge will be considered critical.
The user can define an action to be taken by the power manager in case the battery wish 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 succesitive, so standby timeout less than suspend timeout and so on, but one always can disable any option.
For a laptop users by clicking on the checkbox allows the power manager to reduce the screen luminosity when it detects that system in running on battery power and set it again to the maximum value when 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's a panel plugin that catch the icon and resize 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 is the lowest power level the computer can use. 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 comes up.
- Q: Why the options of suspend/hibernate are not there or i can't select them.
A: Many possible reasons, for example your kernel doesn't or it's 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, then send a DBus 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 take the action defined by the user already and understands that the user insist of using the laptop so in the best cases it'll display a warning popup with options the user can do.
- Q: I select the option of the lcd brightness control but i don't see the brightness changing when i switch from AC adapter to battery power.
A: You kernel doesn't have the right driver, or the driver isn't loaded.
This power manager was written following the philosophy of Xfce, having leight weight application that does what the user expect 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.