SDB:ACPI Suspend with powersaved

Version: 9.1

Situation

You want to use the ACPI functions Suspend to RAM (S3) and Suspend to Disk (S4).

Procedure

ACPI power management is one of the highlights in the new kernel 2.6. Basically, 2.4 series kernels could only use ACPI for resource management but not for power management. Although the kernel 2.6 generally enables ACPI power management, it actually depends on the compatibility of the drivers used (kernel modules). That is why the functions Suspend to RAM and Suspend to Disk are disabled by default.

The file /usr/share/doc/packages/powersave/README.suspend contains all the necessary information to activate these functions. It also includes some indications regarding troubleshooting. Furthermore, you can use the power management YaST2 module to control powersaved.

Note (1): It is always a good idea to install the latest kernel available via YOU (YaST Online Update), because it deals successfully with some of the mentioned restrictions (such as those related to vendor AGP modules), potentially improving the functionality.

Note (2): acpid and powersaved, which is installed and activated by default, cannot run simultaneously. Both daemons attempt to control the ACPI interface, but only one of them can succeed. When acpid and powersaved are started, acpid is the "winner" and powersaved can no longer be successfully started. To avoid this, the service acpid must be disabled:

insserv -r acpid <keyword>ACPI,suspend,S3,S4,powersaved</keyword>