I'm trying to get power management working on my media server (Ubuntu 9) and I found the powernap (also includes powernapd) package. It monitors the system processes and terminal keyboard input to detect idleness then puts the computer into various power saving modes. powernapd uses the "ps -eo args" command to monitor processes. If defined processes are not running for a specified period of time then powernapd thinks the system is idle.
I noticed that media tomb doesn't create another process when streaming media. Is there a way to get media tomb to do this so that powernapd can see that mediatomb is busy playing media.
This combined with WOL (run via my iPhone) will stop my media server chewing through power doing very little 95% of the time.
If this functionality doesn't exist does anyone else want it? I could code a watchdog process which gets kicked off when streaming begins then monitors until streaming ends; then kills itself. Then powernap could be configured to look for the watchdog process.