Power management in GNOME 3.8

In the past couple of weeks, apart from reviewing very many patches for gnome-control-center (especially for new and re-designed panels), I've been working on updating the power management handling in GNOME.

Test suite

The first change is that we have a test suite (currently with 15 separate tests) to test interaction between gnome-settings-daemon's power management and various session and system components. This is thanks to Martin Pitt, and his work on python-dbusmock.

We'll try and add new tests as bug reports come in to avoid regressions, although some cases will remain untested because of limitations in our logging.

 All clear

Screensaver and backlight interaction

With gnome-shell becoming the sole screensaver (after the removal of fallback mode, and the obsoletion of gnome-screensaver), we've been able to streamline the code handling the various screen backlight power levels.

Your screen will now turn off as soon as the screensaver kicks in, moving your mouse in the screensaver will turn it back on for 20 seconds before turning off again, and when to dim (if you've chosen so) is dependent on whether you're on battery or not, and the default idle time (eg. if your screen turns off after 5 minutes of inactivity, the screen will dim after 4). This makes the behaviour more consistent, and predictable, compared to the mish-mash of settings we had before, where some delays were available for change in the UI, and others only through GSettings or gnome-tweak-tool.

Those constants are separate from the code, and exported to the test suite so they are flexible and can be changed if the behaviour doesn't exactly match what users are expecting.

The other change relating to that, is that the screen shield will now always pop down when the screensaver kicks in (thanks to Giovanni for the gnome-shell work). This doesn't mean that you'll have to enter your password each time, but only after the "lock delay" if you've set one.

We've also added a number of nice touches, like the screen turning back on for a short period when you plug or unplug your laptop, made sure that your laptop screen gets turned off and your session locked when closing the lid and turn off the backlight for machines where suspend causes the backlight to come back on temporarily (as seen on MacBooks).

Very very idle

We've also added a long-requested feature: the ability to force logout after a period of idle. This is useful in kiosk and computer lab situations, and is only available through GSettings. As we've added support for this feature (warning prior to logging out, with the screen turning on for a couple of seconds when the warning shows up), we've realised that the infrastructure is the same for automatic suspend/hibernate situation. This means I expect to change the default "long idle" behaviour to suspending. This will still be changeable in the Power preferences. This should land after 3.7.5, and don't worry, we'll make this change very visible in the release notes :)

*I* am not suspending by default

Inhibit

But you don't want to suspend, you really don't.

GNOME supports the draft FreeDesktop "Idle inhibition" specification, as implemented by KDE, which hopefully means that more third-party applications should start behaving better when playing back films, in presentation mode, or for large overnight downloads. This should hopefully get out of draft status before the GNOME 3.8 release.

We also have a gnome-session-inhibit tool available in gnome-session for your scripting needs.

Colophon

 

All the changes mentioned should be available in GNOME 3.7.5, and I will be available to take complaints at FOSDEM this week-end.

Office-runner 1.0

Office Runner 1.0 is now available, downloadable at the usual location.

We had some pretty good comments on the original announcement, even though some people took this opportunity to start slinging insults, which is pretty uncool.

There's plenty of related power management work that's been happening in preparation of GNOME 3.8, and we're mostly waiting on GNOME Shell changes to land before I can talk to you about those. I hope it gets the same (positive) comments as Office Runner did, though I imagine some people will get angry about changes, as they are wont to do.

This version requires systemd for the suspend inhibition.

And don't forget to post your high scores ;)

Guess what I did this week-end? (with stripes)

I watched another nerve-wrecking performance from United. I didn't yell that much though, as I was watching the game with Everton fan Gareth. I'm not one to rub it in.

We also went to said Gareth's girlfriend's birthday party, and had very little luck getting the Kärcher going. The hose keeps popping out under the pressure from the tap (ar, ar).

I've also spent some time trying to get both my laptop and my desktop to suspend. The laptop was fairly straight forward. No hacks, no quirks, just echo mem > /sys/power/state, and you're done. But I'm still hitting a weird bug when using gnome-power-manager to do it.
The desktop (a Dell Optiplex GX620) is a bit more problematic, as pm-suspend doesn't seem to use vbetool at all (despite having an Intel video card in there, but being an older FC6 install...), and the video is completely screwed up (yellow lines, and a lot of flashing blue and red) when resuming under X.

Watched Filles perdues cheveux gras (stopped after 20 minutes, French variété is only below some of their TV shows in things I hate about France), 300 (stopped after about 30 minutes, and finished some weeks later, why would Spartans behave like they were Gulf War I vets), and a Journey Through Porn (stopped 10 minutes near the end to watch Match Of The Day, not great, but still the best docu about pr0n I've seen).


PS: What on earth is going on with them stripes? The window of the local JJB Sports shop. Could it be the metrosexual influence of David Beckham?