Powersave Documentation

Powersave Documentation / HOWTO

This packages was mainly intended for laptops. However more and more features (proper suspend/standby, configure ACPI Buttons, processor frequency scaling (also supported on multi processor machines), spinning down the hard disk, thermal management, ...) became available for workstations and even on servers.

This package unifies the control of power managing facilities on your PC. It supports hardware based on ACPI, APM, IDE-disks and CPU frequency scaling techniques. It takes over functionalities of the apmd, acpid, ospmd and cpufreqd (now called cpuspeed) packages. Therefore you should not install and you must not run daemons from these packages when you run the powersave daemon.
One exception to this rule is acpid - since only one process can access /proc/acpi/event and at least HAL and powersaved need ACPI events, we use acpid as an "event distributor". To achieve this you should configure acpid to not process any events, otherwise you will get undefined results since powersaved also executes actions based on ACPI events. Just removing everything in /etc/acpi/events and putting an empty file named "default" in there should be enough for that.

If your PC does not contain all of the described hardware above (APM and ACPI are mutal exclusive) you should still run this daemon to manage power saving related tasks. The overhead is small and you will be provided with a unique interface and configuration environment. And you can still use this tool if some hardware should change (e.g. booting ACPI instead of APM when kernel provides better ACPI support). The daemon will automatically detect your hardware and support available features.

Among others, the Powersave Daemon provides the following features:

Four predefined powersave schemes, each providing different settings which are fully configurable. Adding of customized schemes is also possible. The current scheme is automatically switched depending on the current power source.
- Powersave
- Performance
- Acoustic
- Presentation
Full support for cpu frequency scaling, either through kernel (ondemand governor) or within userspace. There are three predefined cpu policies.
- Dynamic
- Powersave
- Performance
Battery management. This includes warning the admin/user when a critical battery state is reached and automatic shut down of the system on specific events (fully configurable).
Supporting Suspend to disk, Suspend to and ram and standby. This includes caring about setting up modules, services and a lot more.
Automatic cpu throttling depending on the current cooling policy
Full featured dbus implementation for communication with various clients like kpowersave, wmpowersave, or gkrellm-powersave. More to come...

Get the latest packages from https://sourceforge.net/projects/powersave

Code Documentation

If you are a developer and want to have a look at the code or the internal design, you may look at the Doxygen documentation.

Outdated Documentation and Bug Reporting

Be aware that this project is under developement. If you find outdated or incorrect documentation or any bug, please drop us a mail on powersave-devel@forge.novell.com (subscribe here: http://forge.novell.com/modules/xfmod/maillist/subscribe.php?group_id=1438&list=powersave-devel)

Powersave Documentation