# &application; Manual V&manrevision;

## Introduction

The &app; session daemon is a power management daemon for the `GNOME desktop`

### Differences between suspend and hibernate

The Suspend state is a power saving feature which is the lowest level of power consumption that preserves program data in the computers memory. When your computer is in the Suspended state, computation will not be performed until normal activity is resumed. It will not resume until signaled by an external event such as a keyboard button press. WARNING: You still use a small amount of battery power whilst suspended, so is not recommended for the low power action. If you remove AC power on a desktop, or run out of battery power on a laptop then you will loose your work. It generally takes a few seconds to suspend and then resume your computer.

The Hibernation state saves the complete state of the computer to hard disk and turns off the power, so that the computer appears to be off. It will not resume until signaled by an external event such as a keyboard button press. This is the lowest power sleeping state available. If you remove AC power on a desktop, or run out of battery power on a laptop then work will not be lost. It can take up to a minute or more to hibernate and wake your computer.

## Using &application;

You can start &app; by doing:

Command line

- Type `gnome-power-manager --verbose --no-daemon`, then press Return:

When you start &application;, the following notifications may be displayed.

### &app; Notification when AC adapter is removed

### &app; Notification when laptop primary button is fully charged

### &app; Notification when the system power is critically low

### &app; Notification when battery power is low

### &application; on Startup

&application; on startup

## Preferences

The preferences window allows you to control:

- The LCD brightness when on AC and battery power

- The idle time for the screen power-down and suspend action

- The actions to perform when the laptop lid is closed

- The notification area icon policy

Some sliders or option boxes may be disabled if the gconf policy keys are not writable. This allows admins to lock-down the actions that a user can select.

### &app; AC Power Tab

### &app; Battery Power Tab

### &app; Options Tab

## Advanced Preferences

There are many settings in gconf that are not expressed to the user. These allow &app; to present a simple imterface to the user, but also be flexible for power users.

### Screen Locking

By default, gnome-power-manager supports a simple locking scheme. This means that the screen will lock if set to "Lock screen" in gnome-screensaver when the lid is closed, or the system performs a suspend or hibernate action.

There is a complex locking scheme available for power-users that allows locking policy to change for the lid, suspend and hibernate actions. To enable this complex mode, you will have to disable the gconf key:

- `/apps/gnome-power-manager/lock_use_screensaver_settings`

Then the policy keys can be set to force a gnome-screensaver lock and unlock when the action is performed:

- `/apps/gnome-power-manager/lock_on_blank_screen`

- `/apps/gnome-power-manager/lock_on_suspend`

- `/apps/gnome-power-manager/lock_on_hibernate`

NOTE: The lock policy for gnome-screensaver is ignored until the simple mode is re-enabled.

## Known Bugs and Limitations

This section lists known bugs and limitations using &app;.

### Power consumption when suspended

Your computer still uses a small amount of charge even whilst suspended. If "Suspend" is chosen as the policy option for the battery critical low, and the power completely runs out when sleeping, your work may be lost. See bug #330267 or more details.

## About &app;

&app; was written by Richard Hughes (richard@hughsie.com). To find more information about &app;, please visit the GNOME Power Manager web page.

To report a bug or make a suggestion regarding this application or this manual, follow the directions at the GNOME Power Manager Bug Page.

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. A copy of this license can be found at this link, or in the file COPYING included with the source code of this program.