# &application; Manual

2006
Richard Hughes (richard@hughsie.com)
Richard Hughes

&legal;

Richard
Hughes
richard@hughsie.com
2.0
2006-02-19

Richard Hughes richard@hughsie.com

Richard Hughes

## Feedback

To report a bug or make a suggestion regarding the &app; application or this manual, follow the directions in the GNOME Power Manager Contact Page.

## 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. It generally takes a few seconds to suspend and then resume your computer.

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 lose your work.

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.

## Usage

&app; is usually started in GNOME startup, but you can manually start &app; by doing:

Command line

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

## Notification Messages

When &application; has started, the following notifications may be displayed.

### AC Adapter Unplugged

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

You can disable this notification by changing the gconf key `/apps/gnome-power-manager/notify_ac_adapter`.

### Fully Charged

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

You can disable this notification by changing the gconf key `/apps/gnome-power-manager/notify_fully_charged`.

You will only get a repeat notification if your battery percentage charge drops below 95% and then is again fully charged. This prevents some machines from showing unwanted repeat notifications if the battery is incorrectly reporting the charged status.

### Power Low

When the battery is low, you will recieve the following notification. You should consider switching to battery power really soon.

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

### Power Critical

When the computer has run out of power, it will show this notification explaining what action is required. You can change the critical low action using the preferences tool.

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

### Suspend Failure

When a suspend failure occurs you may get this following warning. The most common reason for this notification is that the current user does not have permission to suspend or hibernate the computer.

#### &app; Notification when suspend failure occurs

## 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 administrators to lock-down the actions that a user can select.

### AC Power Preferences

#### &app; AC Power Tab

### Battery Power Preferences

#### &app; Battery Power Tab

### Preference Options

#### &app; Options Tab

### Session and system idle times

`gnome-screensaver` is a session daemon that monitors user input, and if the mouse has not been moved, or the keyboard been pressed then it starts a timeout. When the value of this timeout reaches the value set in `gnome-screensaver-preferences`, then the login is marked as 'session idle'. This is when &application; performs all the session idle actions such as enabling low-power mode and lowering the laptop panel brightness.

#### Changing the session idle timout in `gnome-screensaver-preferences`

As soon as the session is marked at idle, &application; starts it's own 'system' timer. When the timeout set in `gnome-power-preferences` is reached, and the CPU load is idle, then the idle action is performed, which is usually to turn off the screen, or to suspend or hibernate.

To make this clearer, the sliders in `gnome-power-preferences` are set to start at the value of the session-timout + 1 minute, as we cannot logically trigger before the session is marked as idle. If you adjust the value of the 'session idle' timeout in `gnome-screensaver-preferences` then the start of the sliders in `gnome-power-preferences` will change accordingly.

## Advanced Preferences

### Screen Dim Brightness

You can change the idle laptop panel brightness by changing the gconf key `/apps/gnome-power-manager/laptop_panel_dim_brightness`.

### 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`

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

## Information

The information window allows you to see:

- The power devices attached to your system.

- The percentage change graph of your primary device.

- The time remaining change graph of your primary device.

- The charging and discharge rate graph of your primary device.

- The event log of what's happened in the session.

You man not see some options or graphs if your computer does not have the required hardware. You may also see other hardware not shown here (for example UPS devices) but these are treated the same way as other devices.

### Device Information

The device information tab shows the power hardware attached to your system. You can click on the "More" expanders for more detailed information about your battery device, for instance the design voltage or the capacity percentage for a battery.

#### The devices shown on a typical laptop system with a wireless mouse attached

### Charge History

This graph shows the percentage charge available for the composite primary battery, so if you have a main laptop battery and an auxiliary battery then only the averaged value will be shown. A legend is not shown with this graph.

#### The figure shows a typical discharge with two suspend cycles shown as horizontal lines.

### Power History

This graph shows the power history charge used by the composite primary battery. This line represents the amount of power that is either being used to charge the batteries in the system, or the power being used by the system from the batteries. You should see the line go up when processor intensive tasks are performed, and down when the system is at idle, or when the screen is dimmed. A legend is shown with this graph when data events have been received.

You do will not recieve rate data from your computer if it is not charging or discharging, or if the computer is suspended. This is due to hardware limitiations where the rate is only sent from the battery management chip, rather than the power management chip on the motherboard.

#### The figure shows part of a typical discharge with two suspend cycles.

### Estimated Time History

This graph shows the estimated charge history for the composite primary battery. This line represents the amount of time required until charged, or the amount of time until discharge. This line should go proportionally up when the power decreases and down when the rate increases. A legend is shown with this graph when data events have been received.

#### The figure shows part of a typical discharge with two suspend cycles.

### Event Log

The event log is a record of all the actions that gnome-power-manager has processed. An event might be an dim of the screen, turning on DPMS, or suspending due to system inactivity.

#### The event log showing the time, the event and the event description.

You can clear the event log, or any of the graphs using the "Clear" button. This permanently removes the data from memory.

## About

&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.